[PATCH v10 00/10] Extensions for PTWRITE

[PATCH v10 00/10] Extensions for PTWRITE

[Felix Willgerodt]

From: "Willgerodt, Felix" <felix.willgerodt@intel.com>

v9 can be found here: https://sourceware.org/pipermail/gdb-patches/2023-July/200621.html

I only fixed some small comments by Eli and Tom (thanks!).
But I thought I would post it again anyway. I think what is missing
is another look from Markus and Simon on the new changes since
Simon's review of v7. Those were in patches 5, 8, 9 and 10.

Changes since v9:
* Patch 06: Added NEWS entry.
* Patch 09: Improved and new checks for return values in recpy_call_filter.
* Patch 10: Moved NEWS entry to the right section. Fixed small /doc nit..

Thanks,
Felix

Felix Willgerodt (10):
  btrace: Introduce auxiliary instructions.
  btrace: Enable auxiliary instructions in record instruction-history.
  btrace: Enable auxiliary instructions in record function-call-history.
  btrace: Handle stepping and goto for auxiliary instructions.
  python: Introduce gdb.RecordAuxiliary class.
  python: Add clear() to gdb.Record.
  btrace, gdbserver: Add ptwrite to btrace_config_pt.
  btrace, linux: Enable ptwrite packets.
  btrace, python: Enable ptwrite filter registration.
  btrace: Extend ptwrite event decoding.

 gdb/NEWS                                      |  10 +
 gdb/btrace.c                                  |  72 ++-
 gdb/btrace.h                                  |  41 +-
 gdb/config.in                                 |   3 +
 gdb/configure                                 |  11 +
 gdb/data-directory/Makefile.in                |   1 +
 gdb/disasm-flags.h                            |   1 +
 gdb/doc/gdb.texinfo                           |  32 +-
 gdb/doc/python.texi                           | 167 ++++++
 gdb/extension-priv.h                          |   5 +
 gdb/extension.c                               |  13 +
 gdb/extension.h                               |   3 +
 gdb/features/btrace-conf.dtd                  |   1 +
 gdb/guile/guile.c                             |   1 +
 gdb/nat/linux-btrace.c                        |  58 ++
 gdb/python/lib/gdb/ptwrite.py                 |  77 +++
 gdb/python/py-record-btrace.c                 | 197 ++++++-
 gdb/python/py-record-btrace.h                 |   6 +
 gdb/python/py-record.c                        |  78 ++-
 gdb/python/py-record.h                        |   7 +
 gdb/python/python-internal.h                  |   3 +
 gdb/python/python.c                           |   2 +
 gdb/record-btrace.c                           | 105 +++-
 gdb/record.c                                  |  10 +
 gdb/record.h                                  |   5 +-
 gdb/remote.c                                  |  33 ++
 gdb/testsuite/gdb.btrace/i386-ptwrite.S       | 550 ++++++++++++++++++
 gdb/testsuite/gdb.btrace/ptwrite.c            |  39 ++
 gdb/testsuite/gdb.btrace/ptwrite.exp          | 202 +++++++
 gdb/testsuite/gdb.btrace/x86_64-ptwrite.S     | 544 +++++++++++++++++
 gdb/testsuite/gdb.python/py-record-btrace.exp |   4 +
 gdb/testsuite/lib/gdb.exp                     |  72 +++
 gdbserver/linux-low.cc                        |   3 +
 gdbserver/server.cc                           |  18 +
 gdbsupport/btrace-common.h                    |   6 +
 gdbsupport/common.m4                          |   2 +
 gdbsupport/config.in                          |   3 +
 gdbsupport/configure                          |  11 +
 38 files changed, 2361 insertions(+), 35 deletions(-)
 create mode 100644 gdb/python/lib/gdb/ptwrite.py
 create mode 100644 gdb/testsuite/gdb.btrace/i386-ptwrite.S
 create mode 100644 gdb/testsuite/gdb.btrace/ptwrite.c
 create mode 100644 gdb/testsuite/gdb.btrace/ptwrite.exp
 create mode 100644 gdb/testsuite/gdb.btrace/x86_64-ptwrite.S

-- 
2.34.1

Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

[PATCH v10 01/10] btrace: Introduce auxiliary instructions.

[Felix Willgerodt]

Auxiliary instructions are pseudo instructions pointing to auxiliary data.
This auxiliary data can be printed in all commands displaying (record
function-call-history, record instruction-history) or stepping through
(stepi etc.) the execution history, which will be introduced in the next
commits.

This patch is in preparation for the new ptwrite feature, which is based on
auxiliary instructions.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
---
 gdb/btrace.c        |  2 ++
 gdb/btrace.h        | 24 +++++++++++++++++++++---
 gdb/doc/gdb.texinfo |  3 +++
 3 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/gdb/btrace.c b/gdb/btrace.c
index dbdcea0a8ea..2c20763b570 100644
--- a/gdb/btrace.c
+++ b/gdb/btrace.c
@@ -1823,6 +1823,8 @@ btrace_clear_history (struct btrace_thread_info *btinfo)
   btinfo->insn_history = NULL;
   btinfo->call_history = NULL;
   btinfo->replay = NULL;
+
+  btinfo->aux_data.clear ();
 }
 
 /* Clear the branch trace maintenance histories in BTINFO.  */
diff --git a/gdb/btrace.h b/gdb/btrace.h
index 0ec84113217..dd80d3e6806 100644
--- a/gdb/btrace.h
+++ b/gdb/btrace.h
@@ -52,7 +52,10 @@ enum btrace_insn_class
   BTRACE_INSN_RETURN,
 
   /* The instruction is an unconditional jump.  */
-  BTRACE_INSN_JUMP
+  BTRACE_INSN_JUMP,
+
+  /* The instruction is a pseudo instruction containing auxiliary data.  */
+  BTRACE_INSN_AUX
 };
 
 /* Instruction flags.  */
@@ -68,8 +71,19 @@ DEF_ENUM_FLAGS_TYPE (enum btrace_insn_flag, btrace_insn_flags);
    This represents a single instruction in a branch trace.  */
 struct btrace_insn
 {
-  /* The address of this instruction.  */
-  CORE_ADDR pc;
+  union
+  {
+    /* The address of this instruction.  Applies to btrace_insn with
+       iclass == BTRACE_INSN_OTHER or
+       iclass == BTRACE_INSN_CALL or
+       iclass == BTRACE_INSN_RETURN or
+       iclass == BTRACE_INSN_JUMP.  */
+    CORE_ADDR pc;
+
+    /* Index into btrace_info::aux_data.  Applies to btrace_insn with
+       iclass == BTRACE_INSN_AUX.  */
+    uint64_t aux_data_index;
+  };
 
   /* The size of this instruction in bytes.  */
   gdb_byte size;
@@ -330,6 +344,10 @@ struct btrace_thread_info
      function segment i will be at index (i - 1).  */
   std::vector<btrace_function> functions;
 
+  /* Optional auxiliary information that is printed in all commands
+     displaying or stepping through the execution history.  */
+  std::vector<std::string> aux_data;
+
   /* The function level offset.  When added to each function's LEVEL,
      this normalizes the function levels such that the smallest level
      becomes zero.  */
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index cd86da50f46..b988597cd72 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -7660,6 +7660,9 @@ Moxie, PowerPC, PowerPC64, S/390, and x86 (i386/amd64) running
 GNU/Linux.  Process record and replay can be used both when native
 debugging, and when remote debugging via @code{gdbserver}.
 
+When recording an inferior, @value{GDBN} may print auxiliary information
+during stepping commands and commands displaying the execution history.
+
 For architecture environments that support process record and replay,
 @value{GDBN} provides the following commands:
 
-- 
2.34.1

Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

[PATCH v10 02/10] btrace: Enable auxiliary instructions in record instruction-history.

[Felix Willgerodt]

Print the auxiliary data when a btrace_insn of type BTRACE_INSN_AUX
is encountered in the instruction-history.  Printing is active by default,
it can be silenced with the /a modifier.

This patch is in preparation for the new ptwrite feature, which is based on
auxiliary instructions.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
---
 gdb/disasm-flags.h  |  1 +
 gdb/doc/gdb.texinfo |  3 +++
 gdb/record-btrace.c | 14 ++++++++++++++
 gdb/record.c        |  5 +++++
 4 files changed, 23 insertions(+)

diff --git a/gdb/disasm-flags.h b/gdb/disasm-flags.h
index e2e8a7a82e5..08b2d506493 100644
--- a/gdb/disasm-flags.h
+++ b/gdb/disasm-flags.h
@@ -34,6 +34,7 @@ enum gdb_disassembly_flag : unsigned
     DISASSEMBLY_SOURCE = (0x1 << 5),
     DISASSEMBLY_SPECULATIVE = (0x1 << 6),
     DISASSEMBLY_RAW_BYTES = (0x1 << 7),
+    DISASSEMBLY_OMIT_AUX_INSN = (0x1 << 8),
   };
 DEF_ENUM_FLAGS_TYPE (enum gdb_disassembly_flag, gdb_disassembly_flags);
 
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index b988597cd72..6c812af2b00 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -8078,6 +8078,9 @@ To better align the printed instructions when the trace contains
 instructions from more than one function, the function name may be
 omitted by specifying the @code{/f} modifier.
 
+Printing auxiliary information is enabled by default and can be
+omitted with the @code{/a} modifier.
+
 Speculatively executed instructions are prefixed with @samp{?}.  This
 feature is not available for all recording formats.
 
diff --git a/gdb/record-btrace.c b/gdb/record-btrace.c
index 97447d3e8f8..36247d5b31d 100644
--- a/gdb/record-btrace.c
+++ b/gdb/record-btrace.c
@@ -827,6 +827,20 @@ btrace_insn_history (struct ui_out *uiout,
 	  btrace_ui_out_decode_error (uiout, btrace_insn_get_error (&it),
 				      conf->format);
 	}
+      else if (insn->iclass == BTRACE_INSN_AUX)
+	{
+	  if ((flags & DISASSEMBLY_OMIT_AUX_INSN) != 0)
+	    continue;
+
+	  uiout->field_fmt ("insn-number", "%u", btrace_insn_number (&it));
+	  uiout->text ("\t");
+	  uiout->spaces (3);
+	  uiout->text ("[");
+	  uiout->field_fmt ("aux-data", "%s",
+			    it.btinfo->aux_data.at
+			     (insn->aux_data_index).c_str ());
+	  uiout->text ("]\n");
+	}
       else
 	{
 	  struct disasm_insn dinsn;
diff --git a/gdb/record.c b/gdb/record.c
index f7c82665b05..f1f472aa426 100644
--- a/gdb/record.c
+++ b/gdb/record.c
@@ -487,6 +487,9 @@ get_insn_history_modifiers (const char **arg)
 
 	  switch (*args)
 	    {
+	    case 'a':
+	      modifiers |= DISASSEMBLY_OMIT_AUX_INSN;
+	      break;
 	    case 'm':
 	    case 's':
 	      modifiers |= DISASSEMBLY_SOURCE;
@@ -857,6 +860,8 @@ With a /m or /s modifier, source lines are included (if available).\n\
 With a /r modifier, raw instructions in hex are included.\n\
 With a /f modifier, function names are omitted.\n\
 With a /p modifier, current position markers are omitted.\n\
+With a /a modifier, omits output of auxiliary data, which is enabled \
+by default.\n\
 With no argument, disassembles ten more instructions after the previous \
 disassembly.\n\
 \"record instruction-history -\" disassembles ten instructions before a \
-- 
2.34.1

Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

[PATCH v10 03/10] btrace: Enable auxiliary instructions in record function-call-history.

[Felix Willgerodt]

Print the auxiliary data when a btrace_insn of type BTRACE_INSN_AUX
is encountered in the function-call-history.  Printing is
active by default, it can be silenced with the /a modifier.

This patch is in preparation for the new ptwrite feature, which is based on
auxiliary instructions.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
---
 gdb/btrace.h        |  6 +++++-
 gdb/doc/gdb.texinfo |  5 +++--
 gdb/record-btrace.c | 21 +++++++++++++++++++++
 gdb/record.c        |  5 +++++
 gdb/record.h        |  5 ++++-
 5 files changed, 38 insertions(+), 4 deletions(-)

diff --git a/gdb/btrace.h b/gdb/btrace.h
index dd80d3e6806..f6a8274bb16 100644
--- a/gdb/btrace.h
+++ b/gdb/btrace.h
@@ -105,7 +105,11 @@ enum btrace_function_flag
 
   /* The 'up' link points to a tail call.  This obviously only makes sense
      if bfun_up_links_to_ret is clear.  */
-  BFUN_UP_LINKS_TO_TAILCALL = (1 << 1)
+  BFUN_UP_LINKS_TO_TAILCALL = (1 << 1),
+
+  /* Indicates that at least one auxiliary instruction is in the current
+     function segment.  */
+  BFUN_CONTAINS_AUX = (1 << 2)
 };
 DEF_ENUM_FLAGS_TYPE (enum btrace_function_flag, btrace_function_flags);
 
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 6c812af2b00..2cd0a6c49e7 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -8134,8 +8134,9 @@ that function, the source lines for this instruction sequence (if the
 @code{/l} modifier is specified), and the instructions numbers that form
 the sequence (if the @code{/i} modifier is specified).  The function names
 are indented to reflect the call stack depth if the @code{/c} modifier is
-specified.  The @code{/l}, @code{/i}, and @code{/c} modifiers can be given
-together.
+specified.  Printing auxiliary information is enabled by default and can be
+omitted with the @code{/a} modifier.  The @code{/l}, @code{/i}, @code{/a},
+and @code{/c} modifiers can be given together.
 
 @smallexample
 (@value{GDBP}) @b{list 1, 10}
diff --git a/gdb/record-btrace.c b/gdb/record-btrace.c
index 36247d5b31d..02e71889eaf 100644
--- a/gdb/record-btrace.c
+++ b/gdb/record-btrace.c
@@ -1159,6 +1159,23 @@ btrace_get_bfun_name (const struct btrace_function *bfun)
     return "??";
 }
 
+static void
+btrace_print_aux_insn (struct ui_out *uiout,
+		       const struct btrace_function *bfun,
+		       const struct btrace_thread_info *btinfo)
+{
+  for (const btrace_insn &insn : bfun->insn)
+    {
+      if (insn.iclass == BTRACE_INSN_AUX)
+	{
+	  uiout->text ("\t\t[");
+	  uiout->field_fmt ("aux-data", "%s",
+			    btinfo->aux_data.at (insn.aux_data_index).c_str ());
+	  uiout->text ("]\n");
+	}
+    }
+}
+
 /* Disassemble a section of the recorded function trace.  */
 
 static void
@@ -1234,6 +1251,10 @@ btrace_call_history (struct ui_out *uiout,
 	}
 
       uiout->text ("\n");
+
+      if (((flags & RECORD_DONT_PRINT_AUX) == 0)
+	  && ((bfun->flags & BFUN_CONTAINS_AUX) != 0))
+	btrace_print_aux_insn(uiout, bfun, btinfo);
     }
 }
 
diff --git a/gdb/record.c b/gdb/record.c
index f1f472aa426..c359613913d 100644
--- a/gdb/record.c
+++ b/gdb/record.c
@@ -640,6 +640,9 @@ get_call_history_modifiers (const char **arg)
 	    case 'c':
 	      modifiers |= RECORD_PRINT_INDENT_CALLS;
 	      break;
+	    case 'a':
+	      modifiers |= RECORD_DONT_PRINT_AUX;
+	      break;
 	    default:
 	      error (_("Invalid modifier: %c."), *args);
 	    }
@@ -884,6 +887,8 @@ Without modifiers, it prints the function name.\n\
 With a /l modifier, the source file and line number range is included.\n\
 With a /i modifier, the instruction number range is included.\n\
 With a /c modifier, the output is indented based on the call stack depth.\n\
+With a /a modifier, omits output of auxiliary data, which is enabled \
+by default.\n\
 With no argument, prints ten more lines after the previous ten-line print.\n\
 \"record function-call-history -\" prints ten lines before a previous ten-line \
 print.\n\
diff --git a/gdb/record.h b/gdb/record.h
index 166b5349988..ec06aaa7909 100644
--- a/gdb/record.h
+++ b/gdb/record.h
@@ -62,7 +62,10 @@ enum record_print_flag
   RECORD_PRINT_INSN_RANGE = (1 << 1),
 
   /* Indent based on call stack depth (if applicable).  */
-  RECORD_PRINT_INDENT_CALLS = (1 << 2)
+  RECORD_PRINT_INDENT_CALLS = (1 << 2),
+
+  /* Deactivate printing auxiliary data (if applicable).  */
+  RECORD_DONT_PRINT_AUX = (1 << 3)
 };
 DEF_ENUM_FLAGS_TYPE (enum record_print_flag, record_print_flags);
 
-- 
2.34.1

Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

[PATCH v10 04/10] btrace: Handle stepping and goto for auxiliary instructions.

[Felix Willgerodt]

Print the auxiliary data when stepping. Don't allow to goto an auxiliary
instruction.

This patch is in preparation for the new ptwrite feature, which is based on
auxiliary instructions.
---
 gdb/record-btrace.c | 65 +++++++++++++++++++++++++++++++++++++--------
 1 file changed, 54 insertions(+), 11 deletions(-)

diff --git a/gdb/record-btrace.c b/gdb/record-btrace.c
index 02e71889eaf..c93b3d7c8de 100644
--- a/gdb/record-btrace.c
+++ b/gdb/record-btrace.c
@@ -2380,9 +2380,13 @@ record_btrace_single_step_forward (struct thread_info *tp)
     return btrace_step_stopped ();
 
   /* Skip gaps during replay.  If we end up at a gap (at the end of the trace),
-     jump back to the instruction at which we started.  */
+     jump back to the instruction at which we started.  If we're stepping a
+     BTRACE_INSN_AUX instruction, print the auxiliary data and skip the
+     instruction.  */
+
   start = *replay;
-  do
+
+  for (;;)
     {
       unsigned int steps;
 
@@ -2394,8 +2398,23 @@ record_btrace_single_step_forward (struct thread_info *tp)
 	  *replay = start;
 	  return btrace_step_no_history ();
 	}
+
+      const struct btrace_insn *insn = btrace_insn_get (replay);
+      if (insn == nullptr)
+	continue;
+
+      /* If we're stepping a BTRACE_INSN_AUX instruction, print the auxiliary
+	 data and skip the instruction.  */
+      if (insn->iclass == BTRACE_INSN_AUX)
+	{
+	  gdb_printf ("[%s]\n",
+		      btinfo->aux_data.at (insn->aux_data_index).c_str ());
+	  continue;
+	}
+
+      /* We have an instruction, we are done.  */
+      break;
     }
-  while (btrace_insn_get (replay) == NULL);
 
   /* Determine the end of the instruction trace.  */
   btrace_insn_end (&end, btinfo);
@@ -2426,9 +2445,12 @@ record_btrace_single_step_backward (struct thread_info *tp)
 
   /* If we can't step any further, we reached the end of the history.
      Skip gaps during replay.  If we end up at a gap (at the beginning of
-     the trace), jump back to the instruction at which we started.  */
+     the trace), jump back to the instruction at which we started.
+     If we're stepping a BTRACE_INSN_AUX instruction, print the auxiliary
+     data and skip the instruction.  */
   start = *replay;
-  do
+
+  for (;;)
     {
       unsigned int steps;
 
@@ -2438,8 +2460,22 @@ record_btrace_single_step_backward (struct thread_info *tp)
 	  *replay = start;
 	  return btrace_step_no_history ();
 	}
+
+      const struct btrace_insn *insn = btrace_insn_get (replay);
+      if (insn == nullptr)
+	continue;
+
+      /* Check if we're stepping a BTRACE_INSN_AUX instruction and skip it.  */
+      if (insn->iclass == BTRACE_INSN_AUX)
+	{
+	  gdb_printf ("[%s]\n",
+		      btinfo->aux_data.at (insn->aux_data_index).c_str ());
+	  continue;
+	}
+
+      /* We have an instruction, we are done.  */
+      break;
     }
-  while (btrace_insn_get (replay) == NULL);
 
   /* Check if we're stepping a breakpoint.
 
@@ -2861,26 +2897,33 @@ record_btrace_target::goto_record_end ()
 /* The goto_record method of target record-btrace.  */
 
 void
-record_btrace_target::goto_record (ULONGEST insn)
+record_btrace_target::goto_record (ULONGEST insn_number)
 {
   struct thread_info *tp;
   struct btrace_insn_iterator it;
   unsigned int number;
   int found;
 
-  number = insn;
+  number = insn_number;
 
   /* Check for wrap-arounds.  */
-  if (number != insn)
+  if (number != insn_number)
     error (_("Instruction number out of range."));
 
   tp = require_btrace_thread ();
 
   found = btrace_find_insn_by_number (&it, &tp->btrace, number);
 
-  /* Check if the instruction could not be found or is a gap.  */
-  if (found == 0 || btrace_insn_get (&it) == NULL)
+  /* Check if the instruction could not be found or is a gap or an
+     auxiliary instruction.  */
+  if (found == 0)
+    error (_("No such instruction."));
+
+  const struct btrace_insn *insn = btrace_insn_get (&it);
+  if (insn == NULL)
     error (_("No such instruction."));
+  if (insn->iclass == BTRACE_INSN_AUX)
+    error (_("Can't go to an auxiliary instruction."));
 
   record_btrace_set_replay (tp, &it);
 }
-- 
2.34.1

Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

[PATCH v10 05/10] python: Introduce gdb.RecordAuxiliary class.

[Felix Willgerodt]

Auxiliary instructions are no real instructions and get their own object
class, similar to gaps. gdb.Record.instruction_history is now possibly a
list of gdb.RecordInstruction, gdb.RecordGap or gdb.RecordAuxiliary
objects.

This patch is in preparation for the new ptwrite feature, which is based on
auxiliary instructions.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
---
 gdb/doc/python.texi           | 13 ++++++
 gdb/python/py-record-btrace.c | 81 +++++++++++++++++++++++++++++------
 gdb/python/py-record-btrace.h |  3 ++
 gdb/python/py-record.c        | 62 +++++++++++++++++++++++++--
 gdb/python/py-record.h        |  7 +++
 5 files changed, 150 insertions(+), 16 deletions(-)

diff --git a/gdb/doc/python.texi b/gdb/doc/python.texi
index 9a342f34bf0..46d56464644 100644
--- a/gdb/doc/python.texi
+++ b/gdb/doc/python.texi
@@ -4106,6 +4106,19 @@ the current recording method.
 A human readable string with the reason for the gap.
 @end defvar
 
+Some @value{GDBN} features write auxiliary information into the execution
+history.  This information is represented by a @code{gdb.RecordAuxiliary} object
+in the instruction list.  It has the following attributes:
+
+@defvar RecordAuxiliary.number
+An integer identifying this auxiliary.  @var{number} corresponds to the numbers
+seen in @code{record instruction-history} (@pxref{Process Record and Replay}).
+@end defvar
+
+@defvar RecordAuxiliary.data
+A string representation of the auxiliary data.
+@end defvar
+
 A @code{gdb.RecordFunctionSegment} object has the following attributes:
 
 @defvar RecordFunctionSegment.number
diff --git a/gdb/python/py-record-btrace.c b/gdb/python/py-record-btrace.c
index 7978f3332c6..4a2a61e9b91 100644
--- a/gdb/python/py-record-btrace.c
+++ b/gdb/python/py-record-btrace.c
@@ -45,7 +45,8 @@ struct btpy_list_object {
   /* Stride size.  */
   Py_ssize_t step;
 
-  /* Either &BTPY_CALL_TYPE or &RECPY_INSN_TYPE.  */
+  /* Either &recpy_func_type, &recpy_insn_type, &recpy_aux_type or
+     &recpy_gap_type.  */
   PyTypeObject* element_type;
 };
 
@@ -141,15 +142,21 @@ btrace_func_from_recpy_func (const PyObject * const pyobject)
 }
 
 /* Looks at the recorded item with the number NUMBER and create a
-   gdb.RecordInstruction or gdb.RecordGap object for it accordingly.  */
+   gdb.RecordInstruction, gdb.RecordGap or gdb.RecordAuxiliary object
+   for it accordingly.  */
 
 static PyObject *
-btpy_insn_or_gap_new (thread_info *tinfo, Py_ssize_t number)
+btpy_item_new (thread_info *tinfo, Py_ssize_t number)
 {
   btrace_insn_iterator iter;
   int err_code;
 
-  btrace_find_insn_by_number (&iter, &tinfo->btrace, number);
+  if (btrace_find_insn_by_number (&iter, &tinfo->btrace, number) == 0)
+    {
+      PyErr_Format (gdbpy_gdb_error, _("No such instruction."));
+      return nullptr;
+    }
+
   err_code = btrace_insn_get_error (&iter);
 
   if (err_code != 0)
@@ -163,6 +170,12 @@ btpy_insn_or_gap_new (thread_info *tinfo, Py_ssize_t number)
       return recpy_gap_new (err_code, err_string, number);
     }
 
+  const struct btrace_insn *insn = btrace_insn_get (&iter);
+  gdb_assert (insn != nullptr);
+
+  if (insn->iclass == BTRACE_INSN_AUX)
+    return recpy_aux_new (tinfo, RECORD_METHOD_BTRACE, number);
+
   return recpy_insn_new (tinfo, RECORD_METHOD_BTRACE, number);
 }
 
@@ -424,6 +437,48 @@ recpy_bt_func_next (PyObject *self, void *closure)
 			 RECORD_METHOD_BTRACE, func->next);
 }
 
+/* Implementation of Auxiliary.data [str] for btrace.  */
+
+PyObject *
+recpy_bt_aux_data (PyObject *self, void *closure)
+{
+  const btrace_insn *insn;
+  const recpy_element_object *obj;
+  thread_info *tinfo;
+  btrace_insn_iterator iter;
+
+  if (Py_TYPE (self) != &recpy_aux_type)
+    {
+      PyErr_Format (gdbpy_gdb_error, _("Must be a gdb.Auxiliary."));
+      return NULL;
+    }
+
+  obj = (const recpy_element_object *) self;
+  tinfo = obj->thread;
+
+  if (tinfo == NULL || btrace_is_empty (tinfo))
+    {
+      PyErr_Format (gdbpy_gdb_error, _("No such auxiliary object."));
+      return NULL;
+    }
+
+  if (btrace_find_insn_by_number (&iter, &tinfo->btrace, obj->number) == 0)
+    {
+      PyErr_Format (gdbpy_gdb_error, _("No such auxiliary object."));
+      return NULL;
+    }
+
+  insn = btrace_insn_get (&iter);
+  if (insn == NULL)
+    {
+      PyErr_Format (gdbpy_gdb_error, _("Not a valid auxiliary object."));
+      return NULL;
+    }
+
+  return PyUnicode_FromString
+    (iter.btinfo->aux_data.at (insn->aux_data_index).c_str ());
+}
+
 /* Implementation of BtraceList.__len__ (self) -> int.  */
 
 static Py_ssize_t
@@ -440,8 +495,9 @@ btpy_list_length (PyObject *self)
 }
 
 /* Implementation of
-   BtraceList.__getitem__ (self, key) -> BtraceInstruction and
-   BtraceList.__getitem__ (self, key) -> BtraceFunctionCall.  */
+   BtraceList.__getitem__ (self, key) -> BtraceInstruction,
+   BtraceList.__getitem__ (self, key) -> BtraceFunctionCall,
+   BtraceList.__getitem__ (self, key) -> BtraceAuxiliary.  */
 
 static PyObject *
 btpy_list_item (PyObject *self, Py_ssize_t index)
@@ -455,10 +511,10 @@ btpy_list_item (PyObject *self, Py_ssize_t index)
 
   number = obj->first + (obj->step * index);
 
-  if (obj->element_type == &recpy_insn_type)
-    return recpy_insn_new (obj->thread, RECORD_METHOD_BTRACE, number);
-  else
+  if (obj->element_type == &recpy_func_type)
     return recpy_func_new (obj->thread, RECORD_METHOD_BTRACE, number);
+  else
+    return btpy_item_new (obj->thread, number);
 }
 
 /* Implementation of BtraceList.__getitem__ (self, slice) -> BtraceList.  */
@@ -645,8 +701,7 @@ recpy_bt_replay_position (PyObject *self, void *closure)
   if (tinfo->btrace.replay == NULL)
     Py_RETURN_NONE;
 
-  return btpy_insn_or_gap_new (tinfo,
-			       btrace_insn_number (tinfo->btrace.replay));
+  return btpy_item_new (tinfo, btrace_insn_number (tinfo->btrace.replay));
 }
 
 /* Implementation of
@@ -668,7 +723,7 @@ recpy_bt_begin (PyObject *self, void *closure)
     Py_RETURN_NONE;
 
   btrace_insn_begin (&iterator, &tinfo->btrace);
-  return btpy_insn_or_gap_new (tinfo, btrace_insn_number (&iterator));
+  return btpy_item_new (tinfo, btrace_insn_number (&iterator));
 }
 
 /* Implementation of
@@ -690,7 +745,7 @@ recpy_bt_end (PyObject *self, void *closure)
     Py_RETURN_NONE;
 
   btrace_insn_end (&iterator, &tinfo->btrace);
-  return btpy_insn_or_gap_new (tinfo, btrace_insn_number (&iterator));
+  return btpy_item_new (tinfo, btrace_insn_number (&iterator));
 }
 
 /* Implementation of
diff --git a/gdb/python/py-record-btrace.h b/gdb/python/py-record-btrace.h
index 0af8153b715..0ca3da8e86f 100644
--- a/gdb/python/py-record-btrace.h
+++ b/gdb/python/py-record-btrace.h
@@ -88,4 +88,7 @@ extern PyObject *recpy_bt_func_prev (PyObject *self, void *closure);
 /* Implementation of RecordFunctionSegment.next [RecordFunctionSegment].  */
 extern PyObject *recpy_bt_func_next (PyObject *self, void *closure);
 
+/* Implementation of RecordAuxiliary.decoded [str].  */
+extern PyObject *recpy_bt_aux_data (PyObject *self, void *closure);
+
 #endif /* PYTHON_PY_RECORD_BTRACE_H */
diff --git a/gdb/python/py-record.c b/gdb/python/py-record.c
index c96c649b29c..c093cdaf3d6 100644
--- a/gdb/python/py-record.c
+++ b/gdb/python/py-record.c
@@ -49,6 +49,12 @@ static PyTypeObject recpy_gap_type = {
   PyVarObject_HEAD_INIT (NULL, 0)
 };
 
+/* Python RecordAuxiliary type.  */
+
+PyTypeObject recpy_aux_type = {
+  PyVarObject_HEAD_INIT (nullptr, 0)
+};
+
 /* Python RecordGap object.  */
 struct recpy_gap_object
 {
@@ -390,8 +396,8 @@ recpy_element_hash (PyObject *self)
   return obj->number;
 }
 
-/* Implementation of operator == and != of RecordInstruction and
-   RecordFunctionSegment.  */
+/* Implementation of operator == and != of RecordInstruction,
+   RecordFunctionSegment and RecordAuxiliary.  */
 
 static PyObject *
 recpy_element_richcompare (PyObject *self, PyObject *other, int op)
@@ -479,6 +485,38 @@ recpy_gap_reason_string (PyObject *self, void *closure)
   return PyUnicode_FromString (obj->reason_string);
 }
 
+/* Create a new gdb.Auxiliary object.  */
+
+PyObject *
+recpy_aux_new (thread_info *thread, enum record_method method,
+	       Py_ssize_t number)
+{
+  recpy_element_object * const obj = PyObject_New (recpy_element_object,
+						   &recpy_aux_type);
+
+  if (obj == NULL)
+   return NULL;
+
+  obj->thread = thread;
+  obj->method = method;
+  obj->number = number;
+
+  return (PyObject *) obj;
+}
+
+/* Implementation of Auxiliary.data [buffer].  */
+
+static PyObject *
+recpy_aux_data (PyObject *self, void *closure)
+{
+  const recpy_element_object * const obj = (recpy_element_object *) self;
+
+  if (obj->method == RECORD_METHOD_BTRACE)
+    return recpy_bt_aux_data (self, closure);
+
+  return PyErr_Format (PyExc_NotImplementedError, _("Not implemented."));
+}
+
 /* Record method list.  */
 
 static PyMethodDef recpy_record_methods[] = {
@@ -544,6 +582,14 @@ static gdb_PyGetSetDef recpy_gap_getset[] = {
   { NULL }
 };
 
+/* RecordAuxiliary member list.  */
+
+static gdb_PyGetSetDef recpy_aux_getset[] = {
+  { "number", recpy_element_number, nullptr, "element number", nullptr},
+  { "data", recpy_aux_data, nullptr, "data", nullptr},
+  { nullptr }
+};
+
 /* Sets up the record API in the gdb module.  */
 
 static int CPYCHECKER_NEGATIVE_RESULT_SETS_EXCEPTION
@@ -583,10 +629,20 @@ gdbpy_initialize_record (void)
   recpy_gap_type.tp_doc = "GDB recorded gap object";
   recpy_gap_type.tp_getset = recpy_gap_getset;
 
+  recpy_aux_type.tp_new = PyType_GenericNew;
+  recpy_aux_type.tp_flags = Py_TPFLAGS_DEFAULT;
+  recpy_aux_type.tp_basicsize = sizeof (recpy_element_object);
+  recpy_aux_type.tp_name = "gdb.RecordAuxiliary";
+  recpy_aux_type.tp_doc = "GDB recorded auxiliary object";
+  recpy_aux_type.tp_getset = recpy_aux_getset;
+  recpy_aux_type.tp_richcompare = recpy_element_richcompare;
+  recpy_aux_type.tp_hash = recpy_element_hash;
+
   if (PyType_Ready (&recpy_record_type) < 0
       || PyType_Ready (&recpy_insn_type) < 0
       || PyType_Ready (&recpy_func_type) < 0
-      || PyType_Ready (&recpy_gap_type) < 0)
+      || PyType_Ready (&recpy_gap_type) < 0
+      || PyType_Ready (&recpy_aux_type) < 0)
     return -1;
   else
     return 0;
diff --git a/gdb/python/py-record.h b/gdb/python/py-record.h
index 6eec71e06e7..63e59798a02 100644
--- a/gdb/python/py-record.h
+++ b/gdb/python/py-record.h
@@ -59,6 +59,9 @@ extern PyTypeObject recpy_insn_type;
 /* Python RecordFunctionSegment type.  */
 extern PyTypeObject recpy_func_type;
 
+/* Python RecordAuxiliary type.  */
+extern PyTypeObject recpy_aux_type;
+
 /* Create a new gdb.RecordInstruction object.  */
 extern PyObject *recpy_insn_new (thread_info *thread, enum record_method method,
 				 Py_ssize_t number);
@@ -71,4 +74,8 @@ extern PyObject *recpy_func_new (thread_info *thread, enum record_method method,
 extern PyObject *recpy_gap_new (int reason_code, const char *reason_string,
 				Py_ssize_t number);
 
+/* Create a new gdb.RecordGap object.  */
+extern PyObject *recpy_aux_new (thread_info *thread, enum record_method method,
+				Py_ssize_t number);
+
 #endif /* PYTHON_PY_RECORD_H */
-- 
2.34.1

Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

[PATCH v10 06/10] python: Add clear() to gdb.Record.

[Felix Willgerodt]

This function allows to clear the trace data from python, forcing to
re-decode the trace for successive commands.
This will be used in future ptwrite patches, to trigger re-decoding when
the ptwrite filter changes.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
---
 gdb/NEWS                                      |  3 +++
 gdb/doc/python.texi                           |  5 +++++
 gdb/python/py-record-btrace.c                 | 13 +++++++++++++
 gdb/python/py-record-btrace.h                 |  3 +++
 gdb/python/py-record.c                        | 16 ++++++++++++++++
 gdb/testsuite/gdb.python/py-record-btrace.exp |  4 ++++
 6 files changed, 44 insertions(+)

diff --git a/gdb/NEWS b/gdb/NEWS
index ac5dc424d3f..eeb639d6183 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -157,6 +157,9 @@ info main
 
 * Python API
 
+  ** Added gdb.record.clear(). Clears the trace data of the current recording.
+     This forces re-decoding of the trace for successive commands.
+
   ** gdb.ThreadExitedEvent added.  Emits a ThreadEvent.
 
   ** The gdb.unwinder.Unwinder.name attribute is now read-only.
diff --git a/gdb/doc/python.texi b/gdb/doc/python.texi
index 46d56464644..43f6cecee00 100644
--- a/gdb/doc/python.texi
+++ b/gdb/doc/python.texi
@@ -4051,6 +4051,11 @@ A @code{gdb.Record} object has the following methods:
 Move the replay position to the given @var{instruction}.
 @end defun
 
+@defun Record.clear ()
+Clear the trace data of the current recording.  This forces re-decoding of the
+trace for successive commands.
+@end defun
+
 The common @code{gdb.Instruction} class that recording method specific
 instruction objects inherit from, has the following attributes:
 
diff --git a/gdb/python/py-record-btrace.c b/gdb/python/py-record-btrace.c
index 4a2a61e9b91..7e5bd2c401e 100644
--- a/gdb/python/py-record-btrace.c
+++ b/gdb/python/py-record-btrace.c
@@ -845,6 +845,19 @@ recpy_bt_goto (PyObject *self, PyObject *args)
   Py_RETURN_NONE;
 }
 
+/* Implementation of BtraceRecord.clear (self) -> None.  */
+
+PyObject *
+recpy_bt_clear (PyObject *self, PyObject *args)
+{
+  const recpy_record_object * const record = (recpy_record_object *) self;
+  thread_info *const tinfo = record->thread;
+
+  btrace_clear (tinfo);
+
+  Py_RETURN_NONE;
+}
+
 /* BtraceList methods.  */
 
 static PyMethodDef btpy_list_methods[] =
diff --git a/gdb/python/py-record-btrace.h b/gdb/python/py-record-btrace.h
index 0ca3da8e86f..785999e29e3 100644
--- a/gdb/python/py-record-btrace.h
+++ b/gdb/python/py-record-btrace.h
@@ -31,6 +31,9 @@ extern PyObject *recpy_bt_format (PyObject *self, void *closure);
 /* Implementation of record.goto (instruction) -> None.  */
 extern PyObject *recpy_bt_goto (PyObject *self, PyObject *value);
 
+/* Implementation of BtraceRecord.clear (self) -> None.  */
+extern PyObject *recpy_bt_clear (PyObject *self, PyObject *args);
+
 /* Implementation of record.instruction_history [list].  */
 extern PyObject *recpy_bt_instruction_history (PyObject *self, void *closure);
 
diff --git a/gdb/python/py-record.c b/gdb/python/py-record.c
index c093cdaf3d6..7824dd25953 100644
--- a/gdb/python/py-record.c
+++ b/gdb/python/py-record.c
@@ -115,6 +115,19 @@ recpy_goto (PyObject *self, PyObject *value)
   return PyErr_Format (PyExc_NotImplementedError, _("Not implemented."));
 }
 
+/* Implementation of record.clear () -> None.  */
+
+static PyObject *
+recpy_clear (PyObject *self, PyObject *value)
+{
+  const recpy_record_object * const obj = (recpy_record_object *) self;
+
+  if (obj->method == RECORD_METHOD_BTRACE)
+    return recpy_bt_clear (self, value);
+
+  return PyErr_Format (PyExc_NotImplementedError, _("Not implemented."));
+}
+
 /* Implementation of record.replay_position [instruction]  */
 
 static PyObject *
@@ -523,6 +536,9 @@ static PyMethodDef recpy_record_methods[] = {
   { "goto", recpy_goto, METH_VARARGS,
     "goto (instruction|function_call) -> None.\n\
 Rewind to given location."},
+  { "clear", recpy_clear, METH_VARARGS,
+    "clear () -> None.\n\
+Clears the trace."},
   { NULL }
 };
 
diff --git a/gdb/testsuite/gdb.python/py-record-btrace.exp b/gdb/testsuite/gdb.python/py-record-btrace.exp
index bd397d3c974..fd45891fdfa 100644
--- a/gdb/testsuite/gdb.python/py-record-btrace.exp
+++ b/gdb/testsuite/gdb.python/py-record-btrace.exp
@@ -144,6 +144,10 @@ with_test_prefix "instruction " {
     gdb_test "python print(i.decoded)" ".*"
     gdb_test "python print(i.size)" "$decimal"
     gdb_test "python print(i.is_speculative)" "False"
+    gdb_test_no_output "python r.clear()"
+    gdb_test "python insn = r.instruction_history"
+    gdb_test_no_output "python i = insn\[0\]"
+    gdb_test "python print(i.size)" "$decimal"
 }
 
 with_test_prefix "function call" {
-- 
2.34.1

Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

[PATCH v10 07/10] btrace, gdbserver: Add ptwrite to btrace_config_pt.

[Felix Willgerodt]

This enables gdb and gdbserver to communicate about ptwrite support.  If
ptwrite support would be enabled unconditionally, GDBs with older libipt
versions would break.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
---
 gdb/btrace.c                 |  8 +++++++-
 gdb/doc/gdb.texinfo          | 21 +++++++++++++++++++++
 gdb/features/btrace-conf.dtd |  1 +
 gdb/remote.c                 | 33 +++++++++++++++++++++++++++++++++
 gdbserver/linux-low.cc       |  3 +++
 gdbserver/server.cc          | 18 ++++++++++++++++++
 gdbsupport/btrace-common.h   |  6 ++++++
 7 files changed, 89 insertions(+), 1 deletion(-)

diff --git a/gdb/btrace.c b/gdb/btrace.c
index 2c20763b570..6cbb53b01f1 100644
--- a/gdb/btrace.c
+++ b/gdb/btrace.c
@@ -2273,7 +2273,7 @@ parse_xml_btrace_conf_pt (struct gdb_xml_parser *parser,
 			  std::vector<gdb_xml_value> &attributes)
 {
   struct btrace_config *conf;
-  struct gdb_xml_value *size;
+  struct gdb_xml_value *size, *ptwrite;
 
   conf = (struct btrace_config *) user_data;
   conf->format = BTRACE_FORMAT_PT;
@@ -2282,10 +2282,16 @@ parse_xml_btrace_conf_pt (struct gdb_xml_parser *parser,
   size = xml_find_attribute (attributes, "size");
   if (size != NULL)
     conf->pt.size = (unsigned int) *(ULONGEST *) size->value.get ();
+
+  ptwrite = xml_find_attribute (attributes, "ptwrite");
+  if (ptwrite != nullptr)
+    conf->pt.ptwrite = (bool) *(ULONGEST *) ptwrite->value.get ();
 }
 
 static const struct gdb_xml_attribute btrace_conf_pt_attributes[] = {
   { "size", GDB_XML_AF_OPTIONAL, gdb_xml_parse_attr_ulongest, NULL },
+  { "ptwrite", GDB_XML_AF_OPTIONAL, gdb_xml_parse_attr_enum,
+    gdb_xml_enums_boolean },
   { NULL, GDB_XML_AF_NONE, NULL, NULL }
 };
 
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 2cd0a6c49e7..fa2ad1123ac 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -43943,6 +43943,11 @@ These are the currently defined stub features and their properties:
 @tab @samp{-}
 @tab Yes
 
+@item @samp{Qbtrace-conf:pt:ptwrite}
+@tab Yes
+@tab @samp{-}
+@tab Yes
+
 @item @samp{QNonStop}
 @tab No
 @tab @samp{-}
@@ -44254,6 +44259,9 @@ The remote stub understands the @samp{Qbtrace-conf:bts:size} packet.
 @item Qbtrace-conf:pt:size
 The remote stub understands the @samp{Qbtrace-conf:pt:size} packet.
 
+@item Qbtrace-conf:pt:ptwrite
+The remote stub understands the @samp{Qbtrace-conf:pt:ptwrite} packet.
+
 @item swbreak
 The remote stub reports the @samp{swbreak} stop reason for memory
 breakpoints.
@@ -44761,6 +44769,18 @@ The ring buffer size has been set.
 A badly formed request or an error was encountered.
 @end table
 
+@item Qbtrace-conf:pt:ptwrite=@var{(yes|no)}
+Indicate support for @code{PTWRITE} packets.  This allows for backwards
+compatibility.
+
+Reply:
+@table @samp
+@item OK
+The ptwrite config parameter has been set.
+@item E.errtext
+A badly formed request or an error was encountered.
+@end table
+
 @end table
 
 @node Architecture-Specific Protocol Details
@@ -47409,6 +47429,7 @@ The formal DTD for the branch trace configuration format is given below:
 
 <!ELEMENT pt	EMPTY>
 <!ATTLIST pt	size	CDATA	#IMPLIED>
+<!ATTLIST pt	ptwrite	(yes | no)	#IMPLIED>
 @end smallexample
 
 @include agentexpr.texi
diff --git a/gdb/features/btrace-conf.dtd b/gdb/features/btrace-conf.dtd
index 3fbe3a4dc32..7aeaa4695e1 100644
--- a/gdb/features/btrace-conf.dtd
+++ b/gdb/features/btrace-conf.dtd
@@ -12,3 +12,4 @@
 
 <!ELEMENT pt	EMPTY>
 <!ATTLIST pt	size	CDATA	#IMPLIED>
+<!ATTLIST pt	ptwrite	(yes | no) #IMPLIED>
diff --git a/gdb/remote.c b/gdb/remote.c
index 7e3d6adfe4f..095aa630236 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -286,6 +286,9 @@ enum {
   /* Support for the Qbtrace-conf:pt:size packet.  */
   PACKET_Qbtrace_conf_pt_size,
 
+  /* Support for the Qbtrace-conf:pt:ptwrite packet.  */
+  PACKET_Qbtrace_conf_pt_ptwrite,
+
   /* Support for exec events.  */
   PACKET_exec_event_feature,
 
@@ -5597,6 +5600,8 @@ static const struct protocol_feature remote_protocol_features[] = {
     PACKET_exec_event_feature },
   { "Qbtrace-conf:pt:size", PACKET_DISABLE, remote_supported_packet,
     PACKET_Qbtrace_conf_pt_size },
+  { "Qbtrace-conf:pt:ptwrite", PACKET_DISABLE, remote_supported_packet,
+    PACKET_Qbtrace_conf_pt_ptwrite },
   { "vContSupported", PACKET_DISABLE, remote_supported_packet, PACKET_vContSupported },
   { "QThreadEvents", PACKET_DISABLE, remote_supported_packet, PACKET_QThreadEvents },
   { "no-resumed", PACKET_DISABLE, remote_supported_packet, PACKET_no_resumed },
@@ -14211,6 +14216,31 @@ remote_target::btrace_sync_conf (const btrace_config *conf)
 
       rs->btrace_config.pt.size = conf->pt.size;
     }
+
+  if ((m_features.packet_support (PACKET_Qbtrace_conf_pt_ptwrite)
+       == PACKET_ENABLE)
+	&& conf->pt.ptwrite != rs->btrace_config.pt.ptwrite)
+    {
+      pos = buf;
+      const char *ptw = conf->pt.ptwrite ? "yes" : "no";
+      const char *name
+	= packets_descriptions[PACKET_Qbtrace_conf_pt_ptwrite].name;
+      pos += xsnprintf (pos, endbuf - pos, "%s=\"%s\"", name, ptw);
+
+      putpkt (buf);
+      getpkt (&rs->buf, 0);
+
+      if (m_features.packet_ok (buf, PACKET_Qbtrace_conf_pt_ptwrite)
+	  == PACKET_ERROR)
+	{
+	  if (buf[0] == 'E' && buf[1] == '.')
+	    error (_("Failed to sync ptwrite config: %s"), buf + 2);
+	  else
+	    error (_("Failed to sync ptwrite config."));
+	}
+
+      rs->btrace_config.pt.ptwrite = conf->pt.ptwrite;
+    }
 }
 
 /* Read TP's btrace configuration from the target and store it into CONF.  */
@@ -15390,6 +15420,9 @@ Show the maximum size of the address (in bits) in a memory packet."), NULL,
   add_packet_config_cmd (PACKET_Qbtrace_conf_pt_size, "Qbtrace-conf:pt:size",
 			 "btrace-conf-pt-size", 0);
 
+  add_packet_config_cmd (PACKET_Qbtrace_conf_pt_ptwrite, "Qbtrace-conf:pt:ptwrite",
+			 "btrace-conf-pt-ptwrite", 0);
+
   add_packet_config_cmd (PACKET_vContSupported, "vContSupported",
 			 "verbose-resume-supported", 0);
 
diff --git a/gdbserver/linux-low.cc b/gdbserver/linux-low.cc
index 651f219b738..a4f48b1e4bf 100644
--- a/gdbserver/linux-low.cc
+++ b/gdbserver/linux-low.cc
@@ -6881,6 +6881,9 @@ linux_process_target::read_btrace_conf (const btrace_target_info *tinfo,
 	  string_xml_appendf (*buffer, "<pt");
 	  string_xml_appendf (*buffer, " size=\"0x%x\"", conf->pt.size);
 	  string_xml_appendf (*buffer, "/>\n");
+	  string_xml_appendf (*buffer, " ptwrite=\"%s\"",
+			     conf->pt.ptwrite ? "yes" : "no");
+	  string_xml_appendf (*buffer, "/>\n");
 	  break;
 	}
     }
diff --git a/gdbserver/server.cc b/gdbserver/server.cc
index c57270175b4..f54095b9a37 100644
--- a/gdbserver/server.cc
+++ b/gdbserver/server.cc
@@ -547,6 +547,23 @@ handle_btrace_conf_general_set (char *own_buf)
 
       current_btrace_conf.pt.size = (unsigned int) size;
     }
+  else if (strncmp (op, "pt:ptwrite=", strlen ("pt:ptwrite=")) == 0)
+    {
+      bool ptwrite;
+
+      op += strlen ("pt:ptwrite=");
+      if (strncmp (op, "\"yes\"", strlen ("\"yes\"")) == 0)
+	ptwrite = true;
+      else if (strncmp (op, "\"no\"", strlen ("\"no\"")) == 0)
+	ptwrite = false;
+      else
+	{
+	  strcpy (own_buf, "E.Bad ptwrite value.");
+	  return -1;
+	}
+
+      current_btrace_conf.pt.ptwrite = ptwrite;
+    }
   else
     {
       strcpy (own_buf, "E.Bad Qbtrace configuration option.");
@@ -2146,6 +2163,7 @@ supported_btrace_packets (char *buf)
   strcat (buf, ";Qbtrace-conf:bts:size+");
   strcat (buf, ";Qbtrace:pt+");
   strcat (buf, ";Qbtrace-conf:pt:size+");
+  strcat (buf, ";Qbtrace-conf:pt:ptwrite+");
   strcat (buf, ";Qbtrace:off+");
   strcat (buf, ";qXfer:btrace:read+");
   strcat (buf, ";qXfer:btrace-conf:read+");
diff --git a/gdbsupport/btrace-common.h b/gdbsupport/btrace-common.h
index e287c93a6c1..03cc60648e9 100644
--- a/gdbsupport/btrace-common.h
+++ b/gdbsupport/btrace-common.h
@@ -117,6 +117,12 @@ struct btrace_config_pt
      This is unsigned int and not size_t since it is registered as
      control variable for "set record btrace pt buffer-size".  */
   unsigned int size;
+
+  /* Configuration bit for ptwrite packets.
+
+     If both gdb and gdbserver support this, gdb will try to enable ptwrite
+     packets when tracing is started.  */
+  bool ptwrite;
 };
 
 /* A branch tracing configuration.
-- 
2.34.1

Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

[PATCH v10 08/10] btrace, linux: Enable ptwrite packets.

[Felix Willgerodt]

Enable ptwrite in the PT config, if it is supported by the kernel.
---
 gdb/nat/linux-btrace.c | 58 ++++++++++++++++++++++++++++++++++++++++++
 gdb/record-btrace.c    |  5 ++++
 2 files changed, 63 insertions(+)

diff --git a/gdb/nat/linux-btrace.c b/gdb/nat/linux-btrace.c
index c5b3f1c93cf..689f4c46dd4 100644
--- a/gdb/nat/linux-btrace.c
+++ b/gdb/nat/linux-btrace.c
@@ -417,6 +417,57 @@ cpu_supports_bts (void)
     }
 }
 
+/* Read config bits.  */
+
+static bool
+linux_read_pt_config_bit (const std::string &feature, uint64_t *config_bit)
+{
+  std::string filename
+      = "/sys/bus/event_source/devices/intel_pt/format/" + feature;
+  gdb_file_up file = gdb_fopen_cloexec (filename.c_str (), "r");
+
+  if (file.get () == nullptr || config_bit == nullptr)
+    return false;
+
+  int found = fscanf (file.get (), "config:%lu", config_bit);
+
+  if (found != 1)
+    {
+      warning (_("Failed to determine config bit from %s."),
+	       filename.c_str ());
+      return false;
+    }
+
+  return true;
+}
+
+
+/* Check whether the linux target supports Intel Processor Trace PTWRITE.  */
+
+static bool
+linux_supports_ptwrite (uint64_t *config_bit)
+{
+  static const char filename[]
+      = "/sys/bus/event_source/devices/intel_pt/caps/ptwrite";
+  gdb_file_up file = gdb_fopen_cloexec (filename, "r");
+
+  if (file.get () == nullptr)
+    return false;
+
+  int status, found = fscanf (file.get (), "%d", &status);
+
+  if (found != 1)
+    {
+      warning (_("Failed to determine ptwrite support from %s."), filename);
+      return false;
+    }
+
+  if (!linux_read_pt_config_bit ("ptw", config_bit))
+    return false;
+
+  return status == 1;
+}
+
 /* The perf_event_open syscall failed.  Try to print a helpful error
    message.  */
 
@@ -626,6 +677,13 @@ linux_enable_pt (ptid_t ptid, const struct btrace_config_pt *conf)
   pt->attr.exclude_hv = 1;
   pt->attr.exclude_idle = 1;
 
+  uint64_t config_bit;
+  if (conf->ptwrite && linux_supports_ptwrite (&config_bit))
+    {
+      pt->attr.config |= 1 << config_bit;
+      tinfo->conf.pt.ptwrite = conf->ptwrite;
+    }
+
   errno = 0;
   scoped_fd fd (syscall (SYS_perf_event_open, &pt->attr, pid, -1, -1, 0));
   if (fd.get () < 0)
diff --git a/gdb/record-btrace.c b/gdb/record-btrace.c
index c93b3d7c8de..ad3160d42c5 100644
--- a/gdb/record-btrace.c
+++ b/gdb/record-btrace.c
@@ -3295,4 +3295,9 @@ to see the actual buffer size."), NULL, show_record_pt_buffer_size_value,
 
   record_btrace_conf.bts.size = 64 * 1024;
   record_btrace_conf.pt.size = 16 * 1024;
+#if (LIBIPT_VERSION >= 0x200)
+  record_btrace_conf.pt.ptwrite = true;
+#else
+  record_btrace_conf.pt.ptwrite = false;
+#endif
 }
-- 
2.34.1

Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

[PATCH v10 09/10] btrace, python: Enable ptwrite filter registration.

[Felix Willgerodt]

By default GDB will be printing the hex payload of the ptwrite package as
auxiliary information.  To customize this, the user can register a ptwrite
filter function in python, that takes the payload and the PC as arguments and
returns a string which will be printed instead.  Registering the filter
function is done using a factory pattern to make per-thread filtering easier.
---
 gdb/btrace.c                   |   4 ++
 gdb/btrace.h                   |  11 ++++
 gdb/data-directory/Makefile.in |   1 +
 gdb/extension-priv.h           |   5 ++
 gdb/extension.c                |  13 +++++
 gdb/extension.h                |   3 +
 gdb/guile/guile.c              |   1 +
 gdb/python/lib/gdb/ptwrite.py  |  77 ++++++++++++++++++++++++
 gdb/python/py-record-btrace.c  | 103 +++++++++++++++++++++++++++++++++
 gdb/python/python-internal.h   |   3 +
 gdb/python/python.c            |   2 +
 11 files changed, 223 insertions(+)
 create mode 100644 gdb/python/lib/gdb/ptwrite.py

diff --git a/gdb/btrace.c b/gdb/btrace.c
index 6cbb53b01f1..157d9cc7c38 100644
--- a/gdb/btrace.c
+++ b/gdb/btrace.c
@@ -34,6 +34,7 @@
 #include "gdbsupport/rsp-low.h"
 #include "gdbcmd.h"
 #include "cli/cli-utils.h"
+#include "extension.h"
 #include "gdbarch.h"
 
 /* For maintenance commands.  */
@@ -1317,6 +1318,9 @@ ftrace_add_pt (struct btrace_thread_info *btinfo,
   uint64_t offset;
   int status;
 
+  /* Register the ptwrite filter.  */
+  apply_ext_lang_ptwrite_filter (btinfo);
+
   for (;;)
     {
       struct pt_insn insn;
diff --git a/gdb/btrace.h b/gdb/btrace.h
index f6a8274bb16..137ed0a0238 100644
--- a/gdb/btrace.h
+++ b/gdb/btrace.h
@@ -35,6 +35,7 @@
 #endif
 
 #include <vector>
+#include <string>
 
 struct thread_info;
 struct btrace_function;
@@ -352,6 +353,16 @@ struct btrace_thread_info
      displaying or stepping through the execution history.  */
   std::vector<std::string> aux_data;
 
+  /* Function pointer to the ptwrite callback.  Returns the string returned
+     by the ptwrite filter function.  */
+  gdb::optional<std::string> (*ptw_callback_fun) (const uint64_t payload,
+						  const uint64_t ip,
+						  const void *ptw_context)
+						    = nullptr;
+
+  /* Context for the ptw_callback_fun.  */
+  void *ptw_context = nullptr;
+
   /* The function level offset.  When added to each function's LEVEL,
      this normalizes the function levels such that the smallest level
      becomes zero.  */
diff --git a/gdb/data-directory/Makefile.in b/gdb/data-directory/Makefile.in
index a3775a4a666..388f198b8be 100644
--- a/gdb/data-directory/Makefile.in
+++ b/gdb/data-directory/Makefile.in
@@ -75,6 +75,7 @@ PYTHON_FILE_LIST = \
 	gdb/frames.py \
 	gdb/printing.py \
 	gdb/prompt.py \
+	gdb/ptwrite.py \
 	gdb/styling.py \
 	gdb/types.py \
 	gdb/unwinder.py \
diff --git a/gdb/extension-priv.h b/gdb/extension-priv.h
index 3442302a0be..698cb1ab50e 100644
--- a/gdb/extension-priv.h
+++ b/gdb/extension-priv.h
@@ -184,6 +184,11 @@ struct extension_language_ops
      enum ext_lang_frame_args args_type,
      struct ui_out *out, int frame_low, int frame_high);
 
+  /* Used for registering the ptwrite filter to the current thread.  */
+  void (*apply_ptwrite_filter)
+    (const struct extension_language_defn *extlang,
+     struct btrace_thread_info *btinfo);
+
   /* Update values held by the extension language when OBJFILE is discarded.
      New global types must be created for every such value, which must then be
      updated to use the new types.
diff --git a/gdb/extension.c b/gdb/extension.c
index 65f3bab32a7..b03f4f27d48 100644
--- a/gdb/extension.c
+++ b/gdb/extension.c
@@ -551,6 +551,19 @@ apply_ext_lang_frame_filter (frame_info_ptr frame,
   return EXT_LANG_BT_NO_FILTERS;
 }
 
+/* Used for registering the ptwrite filter to the current thread.  */
+
+void
+apply_ext_lang_ptwrite_filter (btrace_thread_info *btinfo)
+{
+  for (const struct extension_language_defn *extlang : extension_languages)
+    {
+      if (extlang->ops != nullptr
+	  && extlang->ops->apply_ptwrite_filter != nullptr)
+	extlang->ops->apply_ptwrite_filter (extlang, btinfo);
+    }
+}
+
 /* Update values held by the extension language when OBJFILE is discarded.
    New global types must be created for every such value, which must then be
    updated to use the new types.
diff --git a/gdb/extension.h b/gdb/extension.h
index 2b0445133d3..16aa54cb247 100644
--- a/gdb/extension.h
+++ b/gdb/extension.h
@@ -295,6 +295,9 @@ extern enum ext_lang_bt_status apply_ext_lang_frame_filter
    enum ext_lang_frame_args args_type,
    struct ui_out *out, int frame_low, int frame_high);
 
+extern void apply_ext_lang_ptwrite_filter
+  (struct btrace_thread_info *btinfo);
+
 extern void preserve_ext_lang_values (struct objfile *, htab_t copied_types);
 
 extern const struct extension_language_defn *get_breakpoint_cond_ext_lang
diff --git a/gdb/guile/guile.c b/gdb/guile/guile.c
index b45081fe1cc..1388dce5ba0 100644
--- a/gdb/guile/guile.c
+++ b/gdb/guile/guile.c
@@ -125,6 +125,7 @@ static const struct extension_language_ops guile_extension_ops =
   gdbscm_apply_val_pretty_printer,
 
   NULL, /* gdbscm_apply_frame_filter, */
+  NULL, /* gdbscm_load_ptwrite_filter, */
 
   gdbscm_preserve_values,
 
diff --git a/gdb/python/lib/gdb/ptwrite.py b/gdb/python/lib/gdb/ptwrite.py
new file mode 100644
index 00000000000..3be65fedb67
--- /dev/null
+++ b/gdb/python/lib/gdb/ptwrite.py
@@ -0,0 +1,77 @@
+# Ptwrite utilities.
+# Copyright (C) 2023 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+"""Utilities for working with ptwrite filters."""
+
+import gdb
+
+# _ptwrite_filter contains the per thread copies of the filter function.
+# The keys are tuples of inferior id and thread id.
+# The filter functions are created for each thread by calling the
+# _ptwrite_filter_factory.
+_ptwrite_filter = {}
+_ptwrite_filter_factory = None
+
+
+def _ptwrite_exit_handler(event):
+    """Exit handler to prune _ptwrite_filter on thread exit."""
+    _ptwrite_filter.pop(event.inferior_thread.ptid, None)
+
+
+gdb.events.thread_exited.connect(_ptwrite_exit_handler)
+
+
+def _clear_traces():
+    """Helper function to clear the trace of all threads."""
+    current_thread = gdb.selected_thread()
+
+    for inferior in gdb.inferiors():
+        for thread in inferior.threads():
+            thread.switch()
+            recording = gdb.current_recording()
+            if recording is not None:
+                recording.clear()
+
+    current_thread.switch()
+
+
+def register_filter_factory(filter_factory_):
+    """Register the ptwrite filter factory."""
+    if filter_factory_ is not None and not callable(filter_factory_):
+        raise TypeError("The filter factory must be callable or 'None'.")
+
+    # Clear the traces of all threads of all inferiors to force
+    # re-decoding with the new filter.
+    _clear_traces()
+
+    _ptwrite_filter.clear()
+    global _ptwrite_filter_factory
+    _ptwrite_filter_factory = filter_factory_
+
+
+def get_filter():
+    """Returns the filter of the current thread."""
+    thread = gdb.selected_thread()
+    key = thread.ptid
+
+    # Create a new filter for new threads.
+    if key not in _ptwrite_filter:
+        if _ptwrite_filter_factory is not None:
+            _ptwrite_filter[key] = _ptwrite_filter_factory(thread)
+        else:
+            return None
+
+    return _ptwrite_filter[key]
diff --git a/gdb/python/py-record-btrace.c b/gdb/python/py-record-btrace.c
index 7e5bd2c401e..021ea43e221 100644
--- a/gdb/python/py-record-btrace.c
+++ b/gdb/python/py-record-btrace.c
@@ -806,6 +806,109 @@ recpy_bt_function_call_history (PyObject *self, void *closure)
   return btpy_list_new (tinfo, first, last, 1, &recpy_func_type);
 }
 
+/* Helper function that calls PTW_FILTER with PAYLOAD and IP as arguments.
+   Returns the string that will be printed, if there is a filter to call.  */
+static gdb::optional<std::string>
+recpy_call_filter (const uint64_t payload, const uint64_t ip,
+		   const void *ptw_filter)
+{
+  gdb::optional<std::string> result;
+
+  gdb_assert (ptw_filter != nullptr);
+  if ((PyObject *) ptw_filter == Py_None)
+    return result;
+
+  gdbpy_enter enter_py;
+
+  gdbpy_ref<> py_payload (PyLong_FromUnsignedLongLong (payload));
+
+  if (py_payload == nullptr)
+    return result;
+
+  gdbpy_ref<> py_ip;
+
+  if (ip == 0)
+    py_ip = gdbpy_ref<>::new_reference (Py_None);
+  else
+    py_ip = gdbpy_ref<>::new_reference (PyLong_FromUnsignedLongLong (ip));
+
+  if (py_ip == nullptr)
+    return result;
+
+  gdbpy_ref<> py_result (PyObject_CallFunctionObjArgs ((PyObject *) ptw_filter,
+							py_payload.get (),
+							py_ip.get (),
+							nullptr));
+
+  if (py_result == nullptr)
+    {
+      gdbpy_print_stack ();
+      gdbpy_error (_("Couldn't call the ptwrite filter."));
+    }
+
+  /* Py_None is valid and results in no output.  */
+  if (py_result == Py_None)
+    {
+      result = "";
+      return result;
+    }
+
+  gdb::unique_xmalloc_ptr<char> user_string
+    = gdbpy_obj_to_string (py_result.get ());
+
+  if (user_string == nullptr)
+    {
+      gdbpy_print_stack ();
+      gdbpy_error (_("The ptwrite filter didn't return a string."));
+    }
+  else
+    result = user_string.get ();
+
+  return result;
+}
+
+/* Helper function returning the current ptwrite filter.  */
+
+static PyObject *
+get_ptwrite_filter ()
+{
+  gdbpy_ref<> module (PyImport_ImportModule ("gdb.ptwrite"));
+
+  if (PyErr_Occurred ())
+  {
+    gdbpy_print_stack ();
+    return nullptr;
+  }
+
+  /* We need to keep the reference count.  */
+  gdbpy_ref<> ptw_filter (PyObject_CallMethod (module.get (), "get_filter",
+					       nullptr));
+
+  if (PyErr_Occurred ())
+    {
+      gdbpy_print_stack ();
+      gdbpy_error (_("Couldn't get the ptwrite filter."));
+    }
+
+  return ptw_filter.get();
+}
+
+/* Used for registering the default ptwrite filter to the current thread.  A
+   pointer to this function is stored in the python extension interface.  */
+
+void
+gdbpy_load_ptwrite_filter (const struct extension_language_defn *extlang,
+			   struct btrace_thread_info *btinfo)
+{
+  gdb_assert (btinfo != nullptr);
+
+  gdbpy_enter enter_py;
+
+  btinfo->ptw_context = get_ptwrite_filter ();
+  if (btinfo->ptw_context != nullptr)
+    btinfo->ptw_callback_fun = &recpy_call_filter;
+}
+
 /* Implementation of BtraceRecord.goto (self, BtraceInstruction) -> None.  */
 
 PyObject *
diff --git a/gdb/python/python-internal.h b/gdb/python/python-internal.h
index 93217375cc5..f44ad11cdf0 100644
--- a/gdb/python/python-internal.h
+++ b/gdb/python/python-internal.h
@@ -378,6 +378,9 @@ extern enum ext_lang_rc gdbpy_apply_val_pretty_printer
    struct ui_file *stream, int recurse,
    const struct value_print_options *options,
    const struct language_defn *language);
+extern void gdbpy_load_ptwrite_filter
+  (const struct extension_language_defn *extlang,
+   struct btrace_thread_info *btinfo);
 extern enum ext_lang_bt_status gdbpy_apply_frame_filter
   (const struct extension_language_defn *,
    frame_info_ptr frame, frame_filter_flags flags,
diff --git a/gdb/python/python.c b/gdb/python/python.c
index 505fc4412d1..bd578a16fa5 100644
--- a/gdb/python/python.c
+++ b/gdb/python/python.c
@@ -153,6 +153,8 @@ static const struct extension_language_ops python_extension_ops =
 
   gdbpy_apply_frame_filter,
 
+  gdbpy_load_ptwrite_filter,
+
   gdbpy_preserve_values,
 
   gdbpy_breakpoint_has_cond,
-- 
2.34.1

Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

[PATCH v10 10/10] btrace: Extend ptwrite event decoding.

[Felix Willgerodt]

Call the ptwrite filter function whenever a ptwrite event is decoded.
The returned string is written to the aux_data string table and a
corresponding auxiliary instruction is appended to the function segment.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
---
 gdb/NEWS                                  |   7 +
 gdb/btrace.c                              |  58 +++
 gdb/config.in                             |   3 +
 gdb/configure                             |  11 +
 gdb/doc/python.texi                       | 149 ++++++
 gdb/testsuite/gdb.btrace/i386-ptwrite.S   | 550 ++++++++++++++++++++++
 gdb/testsuite/gdb.btrace/ptwrite.c        |  39 ++
 gdb/testsuite/gdb.btrace/ptwrite.exp      | 202 ++++++++
 gdb/testsuite/gdb.btrace/x86_64-ptwrite.S | 544 +++++++++++++++++++++
 gdb/testsuite/lib/gdb.exp                 |  72 +++
 gdbsupport/common.m4                      |   2 +
 gdbsupport/config.in                      |   3 +
 gdbsupport/configure                      |  11 +
 13 files changed, 1651 insertions(+)
 create mode 100644 gdb/testsuite/gdb.btrace/i386-ptwrite.S
 create mode 100644 gdb/testsuite/gdb.btrace/ptwrite.c
 create mode 100644 gdb/testsuite/gdb.btrace/ptwrite.exp
 create mode 100644 gdb/testsuite/gdb.btrace/x86_64-ptwrite.S

diff --git a/gdb/NEWS b/gdb/NEWS
index eeb639d6183..c92da7d5727 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -3,6 +3,13 @@
 
 *** Changes since GDB 13
 
+* GDB now supports printing of ptwrite payloads from the Intel Processor
+  Trace during 'record instruction-history', 'record function-call-history'
+  and all stepping commands.  The payload is also accessible in Python as a
+  RecordAuxiliary object.  Printing is customizable via a ptwrite filter
+  function in Python.  By default, the raw ptwrite payload is printed for
+  each ptwrite that is encountered.
+
 * The AArch64 'org.gnu.gdb.aarch64.pauth' Pointer Authentication feature string
   has been deprecated in favor of the 'org.gnu.gdb.aarch64.pauth_v2' feature
   string.
diff --git a/gdb/btrace.c b/gdb/btrace.c
index 157d9cc7c38..70ccc0951a3 100644
--- a/gdb/btrace.c
+++ b/gdb/btrace.c
@@ -43,6 +43,7 @@
 #include <inttypes.h>
 #include <ctype.h>
 #include <algorithm>
+#include <string>
 
 /* Command lists for btrace maintenance commands.  */
 static struct cmd_list_element *maint_btrace_cmdlist;
@@ -1253,6 +1254,57 @@ handle_pt_insn_events (struct btrace_thread_info *btinfo,
 		   bfun->insn_offset - 1, offset);
 
 	  break;
+#if defined (HAVE_STRUCT_PT_EVENT_VARIANT_PTWRITE)
+	case ptev_ptwrite:
+	  {
+	    uint64_t ip = 0;
+	    gdb::optional<std::string> ptw_string;
+	    btrace_insn_flags flags = 0;
+
+	    /* Lookup the ip if available.  */
+	    if (event.ip_suppressed == 0)
+	      ip = event.variant.ptwrite.ip;
+
+	    if (btinfo->ptw_callback_fun != nullptr)
+	      ptw_string
+		= btinfo->ptw_callback_fun (event.variant.ptwrite.payload,
+					    ip, btinfo->ptw_context);
+
+	    if (ptw_string.has_value () && (*ptw_string).empty ())
+	      continue;
+
+	    if (!ptw_string.has_value ())
+	      *ptw_string = hex_string (event.variant.ptwrite.payload);
+
+	    btinfo->aux_data.emplace_back (std::move (*ptw_string));
+
+	    if (!btinfo->functions.empty ()
+		&& !btinfo->functions.back ().insn.empty ())
+	      flags = btinfo->functions.back ().insn.back ().flags;
+
+	    /* Update insn list with ptw payload insn.  */
+	    struct btrace_insn ptw_insn;
+	    ptw_insn.aux_data_index = btinfo->aux_data.size () - 1;
+	    ptw_insn.size = 0;
+	    ptw_insn.iclass = BTRACE_INSN_AUX;
+	    ptw_insn.flags = flags;
+
+	    if (ip != 0)
+	      bfun = ftrace_update_function (btinfo, ip);
+	    else
+	      {
+		if (btinfo->functions.empty ())
+		  bfun = ftrace_new_function (btinfo, NULL, NULL);
+		else
+		  bfun = &btinfo->functions.back ();
+	      }
+
+	    bfun->flags |= BFUN_CONTAINS_AUX;
+	    ftrace_update_insns (bfun, ptw_insn);
+
+	    break;
+	  }
+#endif /* defined (HAVE_STRUCT_PT_EVENT_VARIANT_PTWRITE) */
 	}
     }
 #endif /* defined (HAVE_PT_INSN_EVENT) */
@@ -2981,6 +3033,12 @@ pt_print_packet (const struct pt_packet *packet)
     case ppt_mnt:
       gdb_printf (("mnt %" PRIx64 ""), packet->payload.mnt.payload);
       break;
+
+#if defined (HAVE_STRUCT_PT_EVENT_VARIANT_PTWRITE)
+    case ppt_ptw:
+      gdb_printf (("ptw %" PRIx64 ""), packet->payload.ptw.payload);
+      break;
+#endif /* defined (HAVE_STRUCT_PT_EVENT_VARIANT_PTWRITE) */
     }
 }
 
diff --git a/gdb/config.in b/gdb/config.in
index bc562669d2c..19a33a6e74a 100644
--- a/gdb/config.in
+++ b/gdb/config.in
@@ -460,6 +460,9 @@
 /* Define to 1 if `pl_tdname' is a member of `struct ptrace_lwpinfo'. */
 #undef HAVE_STRUCT_PTRACE_LWPINFO_PL_TDNAME
 
+/* Define to 1 if `variant.ptwrite' is a member of `struct pt_event'. */
+#undef HAVE_STRUCT_PT_EVENT_VARIANT_PTWRITE
+
 /* Define to 1 if `enabled' is a member of `struct pt_insn'. */
 #undef HAVE_STRUCT_PT_INSN_ENABLED
 
diff --git a/gdb/configure b/gdb/configure
index 637f9cd7296..d4cb147e9ea 100755
--- a/gdb/configure
+++ b/gdb/configure
@@ -25770,6 +25770,17 @@ cat >>confdefs.h <<_ACEOF
 _ACEOF
 
 
+fi
+
+      ac_fn_c_check_member "$LINENO" "struct pt_event" "variant.ptwrite" "ac_cv_member_struct_pt_event_variant_ptwrite" "#include <intel-pt.h>
+"
+if test "x$ac_cv_member_struct_pt_event_variant_ptwrite" = xyes; then :
+
+cat >>confdefs.h <<_ACEOF
+#define HAVE_STRUCT_PT_EVENT_VARIANT_PTWRITE 1
+_ACEOF
+
+
 fi
 
       LIBS=$save_LIBS
diff --git a/gdb/doc/python.texi b/gdb/doc/python.texi
index 43f6cecee00..d2c9aac7be3 100644
--- a/gdb/doc/python.texi
+++ b/gdb/doc/python.texi
@@ -7676,6 +7676,7 @@ registering objfile-specific pretty-printers and frame-filters.
 * gdb.printing::       Building and registering pretty-printers.
 * gdb.types::          Utilities for working with types.
 * gdb.prompt::         Utilities for prompt value substitution.
+* gdb.ptwrite::        Utilities for PTWRITE filter registration.
 @end menu
 
 @node gdb.printing
@@ -7866,3 +7867,151 @@ substitute_prompt ("frame: \f, args: \p@{print frame-arguments@}")
 "frame: main, args: scalars"
 @end smallexample
 @end table
+
+@node gdb.ptwrite
+@subsubsection gdb.ptwrite
+@cindex gdb.ptwrite
+
+This module provides additional functionality for recording programs that
+make use of the @code{PTWRITE} instruction.  @code{PTWRITE} is a x86
+instruction that allows to write values into the Intel Processor Trace
+(@pxref{Process Record and Replay}).
+The @value{NGCC} built-in functions for it are:
+@smallexample
+void __builtin_ia32_ptwrite32 (unsigned);
+void __builtin_ia32_ptwrite64 (unsigned long long);
+@end smallexample
+
+If an inferior uses the instruction, @value{GDBN} by default inserts the
+raw payload value as auxiliary information into the execution history.
+Auxiliary information is by default printed during
+@code{record instruction-history}, @code{record function-call-history},
+and all stepping commands, and is accessible in Python as a
+@code{RecordAuxiliary} object.
+
+@exdent Sample program:
+@smallexample
+@group
+void
+ptwrite64 (unsigned long long value)
+@{
+  __builtin_ia32_ptwrite64 (value);
+@}
+@end group
+
+@group
+int
+main (void)
+@{
+  ptwrite64 (0x42);
+  return 0; /* break here.  */
+@}
+@end group
+@end smallexample
+
+
+@exdent @value{GDBN} output after recording the sample program in pt format:
+@smallexample
+@group
+(gdb) record instruction-history 12,14
+12         0x0040074c <ptwrite64+16>:   ptwrite %rbx
+13         [0x42]
+14         0x00400751 <ptwrite64+21>:   mov -0x8(%rbp),%rbx
+(gdb) record function-call-history
+1       main
+2       ptwrite64
+                [0x42]
+3       main
+@end group
+@end smallexample
+
+The @code{gdb.ptwrite} module allows customizing the default output of
+@code{PTWRITE} auxiliary information.  A custom Python function can be
+registered as the @code{PTWRITE} filter function.  This function will be
+called with the @code{PTWRITE} payload and PC as arguments during trace
+decoding.  It can return a string, which will be printed by @value{GDBN}
+during the aforementioned commands, or @code{None}, resulting in no output.
+To register such a filter function, the user needs to provide a filter factory
+function, which returns a new filter function object to be called by
+@value{GDBN}.
+
+@findex gdb.ptwrite.register_filter_factory
+@defun register_filter_factory (filter_factory)
+Used to register the @code{PTWRITE} filter factory.  This filter factory can
+be any callable object that accepts one argument, the current thread as
+a @code{gdb.InferiorThread}.
+It can return None or a callable.  This callable is the @code{PTWRITE} filter
+function for the specified thread.  If @code{None} is returned by the factory
+function, the default auxiliary information will be printed.
+@end defun
+
+@findex gdb.ptwrite.get_filter
+@defun get_filter ()
+Return the currently active @code{PTWRITE} filter function.
+@end defun
+
+An example:
+
+@smallexample
+@group
+(gdb) python-interactive
+>>> class my_filter():
+...    def __init__(self):
+...        self.var = 0
+...    def __call__(self, payload, ip):
+...        self.var += 1
+...        return f"counter: @{self.var@}, ip: @{ip:#x@}"
+...
+>>> def my_filter_factory(thread):
+...    if thread.global_num == 1:
+...        return my_filter()
+...    else:
+...        return None
+...
+>>> import gdb.ptwrite
+>>> gdb.ptwrite.register_filter_factory(my_filter_factory)
+>>>
+@end group
+
+@group
+(gdb) record function-call-history 59,64
+59      pthread_create@@GLIBC_2.2.5
+60      job()
+61      task(void*)
+62      ptwrite64(unsigned long)
+                [counter: 1, ip: 0x401156]
+63      task(void*)
+64      ptwrite32(unsigned int)
+                [counter: 2, ip: 0x40116c]
+@end group
+
+@group
+(gdb) info threads
+* 1    Thread 0x7ffff7fd8740 (LWP 25796) "ptw_threads" task ()
+    at bin/ptwrite/ptw_threads.c:45
+  2    Thread 0x7ffff6eb8700 (LWP 25797) "ptw_threads" task ()
+    at bin/ptwrite/ptw_threads.c:45
+@end group
+
+@group
+(gdb) thread 2
+[Switching to thread 2 (Thread 0x7ffff6eb8700 (LWP 25797))]
+#0  task (arg=0x0) at ptwrite_threads.c:45
+45        return NULL;
+@end group
+
+@group
+(gdb) record function-call-history 10,14
+10    start_thread
+11    task(void*)
+12    ptwrite64(unsigned long)
+              [0x42]
+13    task(void*)
+14    ptwrite32(unsigned int)
+              [0x43]
+@end group
+@end smallexample
+
+This @value{GDBN} feature is dependent on hardware and operating system
+support and requires the Intel Processor Trace decoder library in version
+2.0.0 or newer.
diff --git a/gdb/testsuite/gdb.btrace/i386-ptwrite.S b/gdb/testsuite/gdb.btrace/i386-ptwrite.S
new file mode 100644
index 00000000000..3e09bc938a1
--- /dev/null
+++ b/gdb/testsuite/gdb.btrace/i386-ptwrite.S
@@ -0,0 +1,550 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2023 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+   This file has been generated using gcc version 10.3.1 20210422
+   (Red Hat 10.3.1-1):
+   gcc -S -dA -g -m32 -mptwrite ptwrite.c -o i386-ptwrite.S.  */
+
+
+	.file	"ptwrite.c"
+	.text
+.Ltext0:
+	.globl	ptwrite1
+	.type	ptwrite1, @function
+ptwrite1:
+.LFB4021:
+	.file 1 "ptwrite.c"
+	# ptwrite.c:22:1
+	.loc 1 22 1
+	.cfi_startproc
+# BLOCK 2 seq:0
+# PRED: ENTRY (FALLTHRU)
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	subl	$16, %esp
+	# ptwrite.c:23:3
+	.loc 1 23 3
+	movl	8(%ebp), %eax
+	movl	%eax, -4(%ebp)
+.LBB6:
+.LBB7:
+	.file 2 "/usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h"
+	# /usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h:307:3
+	.loc 2 307 3
+	movl	-4(%ebp), %eax
+	ptwrite	%eax
+	# /usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h:308:1
+	.loc 2 308 1
+	nop
+.LBE7:
+.LBE6:
+	# ptwrite.c:24:1
+	.loc 1 24 1
+	nop
+	leave
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+# SUCC: EXIT [always]
+	ret
+	.cfi_endproc
+.LFE4021:
+	.size	ptwrite1, .-ptwrite1
+	.globl	ptwrite2
+	.type	ptwrite2, @function
+ptwrite2:
+.LFB4022:
+	# ptwrite.c:28:1
+	.loc 1 28 1
+	.cfi_startproc
+# BLOCK 2 seq:0
+# PRED: ENTRY (FALLTHRU)
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	subl	$16, %esp
+	# ptwrite.c:29:3
+	.loc 1 29 3
+	movl	8(%ebp), %eax
+	movl	%eax, -4(%ebp)
+.LBB8:
+.LBB9:
+	# /usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h:307:3
+	.loc 2 307 3
+	movl	-4(%ebp), %eax
+	ptwrite	%eax
+	# /usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h:308:1
+	.loc 2 308 1
+	nop
+.LBE9:
+.LBE8:
+	# ptwrite.c:30:1
+	.loc 1 30 1
+	nop
+	leave
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+# SUCC: EXIT [always]
+	ret
+	.cfi_endproc
+.LFE4022:
+	.size	ptwrite2, .-ptwrite2
+	.globl	main
+	.type	main, @function
+main:
+.LFB4023:
+	# ptwrite.c:34:1
+	.loc 1 34 1
+	.cfi_startproc
+# BLOCK 2 seq:0
+# PRED: ENTRY (FALLTHRU)
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	# ptwrite.c:35:3
+	.loc 1 35 3
+	pushl	$66
+	call	ptwrite1
+	addl	$4, %esp
+	# ptwrite.c:36:3
+	.loc 1 36 3
+	pushl	$67
+	call	ptwrite2
+	addl	$4, %esp
+	# ptwrite.c:38:10
+	.loc 1 38 10
+	movl	$0, %eax
+	# ptwrite.c:39:1
+	.loc 1 39 1
+	leave
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+# SUCC: EXIT [always]
+	ret
+	.cfi_endproc
+.LFE4023:
+	.size	main, .-main
+.Letext0:
+	.section	.debug_info,"",@progbits
+.Ldebug_info0:
+	.long	0x129	# Length of Compilation Unit Info
+	.value	0x4	# DWARF version number
+	.long	.Ldebug_abbrev0	# Offset Into Abbrev. Section
+	.byte	0x4	# Pointer Size (in bytes)
+	.uleb128 0x1	# (DIE (0xb) DW_TAG_compile_unit)
+	.long	.LASF15	# DW_AT_producer: "GNU C17 10.3.1 20210422 (Red Hat 10.3.1-1) -m32 -mptwrite -mtune=generic -march=i686 -g"
+	.byte	0xc	# DW_AT_language
+	.long	.LASF16	# DW_AT_name: "ptwrite.c"
+	.long	.LASF17	# DW_AT_comp_dir: "gdb/gdb/testsuite/gdb.btrace"
+	.long	.Ltext0	# DW_AT_low_pc
+	.long	.Letext0-.Ltext0	# DW_AT_high_pc
+	.long	.Ldebug_line0	# DW_AT_stmt_list
+	.uleb128 0x2	# (DIE (0x25) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.ascii "int\0"	# DW_AT_name
+	.uleb128 0x3	# (DIE (0x2c) DW_TAG_base_type)
+	.byte	0x2	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.long	.LASF0	# DW_AT_name: "short int"
+	.uleb128 0x3	# (DIE (0x33) DW_TAG_base_type)
+	.byte	0x1	# DW_AT_byte_size
+	.byte	0x6	# DW_AT_encoding
+	.long	.LASF1	# DW_AT_name: "char"
+	.uleb128 0x3	# (DIE (0x3a) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.long	.LASF2	# DW_AT_name: "long long int"
+	.uleb128 0x3	# (DIE (0x41) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x4	# DW_AT_encoding
+	.long	.LASF3	# DW_AT_name: "float"
+	.uleb128 0x3	# (DIE (0x48) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x7	# DW_AT_encoding
+	.long	.LASF4	# DW_AT_name: "unsigned int"
+	.uleb128 0x3	# (DIE (0x4f) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.long	.LASF5	# DW_AT_name: "long int"
+	.uleb128 0x3	# (DIE (0x56) DW_TAG_base_type)
+	.byte	0x1	# DW_AT_byte_size
+	.byte	0x8	# DW_AT_encoding
+	.long	.LASF6	# DW_AT_name: "unsigned char"
+	.uleb128 0x3	# (DIE (0x5d) DW_TAG_base_type)
+	.byte	0x2	# DW_AT_byte_size
+	.byte	0x7	# DW_AT_encoding
+	.long	.LASF7	# DW_AT_name: "short unsigned int"
+	.uleb128 0x3	# (DIE (0x64) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x7	# DW_AT_encoding
+	.long	.LASF8	# DW_AT_name: "long unsigned int"
+	.uleb128 0x3	# (DIE (0x6b) DW_TAG_base_type)
+	.byte	0x1	# DW_AT_byte_size
+	.byte	0x6	# DW_AT_encoding
+	.long	.LASF9	# DW_AT_name: "signed char"
+	.uleb128 0x3	# (DIE (0x72) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x7	# DW_AT_encoding
+	.long	.LASF10	# DW_AT_name: "long long unsigned int"
+	.uleb128 0x3	# (DIE (0x79) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x4	# DW_AT_encoding
+	.long	.LASF11	# DW_AT_name: "double"
+	.uleb128 0x4	# (DIE (0x80) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF18	# DW_AT_name: "main"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x21	# DW_AT_decl_line
+	.byte	0x1	# DW_AT_decl_column
+			# DW_AT_prototyped
+	.long	0x25	# DW_AT_type
+	.long	.LFB4023	# DW_AT_low_pc
+	.long	.LFE4023-.LFB4023	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_tail_call_sites
+	.uleb128 0x5	# (DIE (0x96) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF12	# DW_AT_name: "ptwrite2"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x1b	# DW_AT_decl_line
+	.byte	0x1	# DW_AT_decl_column
+			# DW_AT_prototyped
+	.long	.LFB4022	# DW_AT_low_pc
+	.long	.LFE4022-.LFB4022	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_call_sites
+	.long	0xd5	# DW_AT_sibling
+	.uleb128 0x6	# (DIE (0xac) DW_TAG_formal_parameter)
+	.long	.LASF14	# DW_AT_name: "value"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x1b	# DW_AT_decl_line
+	.byte	0xf	# DW_AT_decl_column
+	.long	0x25	# DW_AT_type
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 0
+	.uleb128 0x7	# (DIE (0xbb) DW_TAG_inlined_subroutine)
+	.long	0x114	# DW_AT_abstract_origin
+	.long	.LBB8	# DW_AT_low_pc
+	.long	.LBE8-.LBB8	# DW_AT_high_pc
+	.byte	0x1	# DW_AT_call_file (ptwrite.c)
+	.byte	0x1d	# DW_AT_call_line
+	.byte	0x3	# DW_AT_call_column
+	.uleb128 0x8	# (DIE (0xcb) DW_TAG_formal_parameter)
+	.long	0x11e	# DW_AT_abstract_origin
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -12
+	.byte	0	# end of children of DIE 0xbb
+	.byte	0	# end of children of DIE 0x96
+	.uleb128 0x5	# (DIE (0xd5) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF13	# DW_AT_name: "ptwrite1"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x15	# DW_AT_decl_line
+	.byte	0x1	# DW_AT_decl_column
+			# DW_AT_prototyped
+	.long	.LFB4021	# DW_AT_low_pc
+	.long	.LFE4021-.LFB4021	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_call_sites
+	.long	0x114	# DW_AT_sibling
+	.uleb128 0x6	# (DIE (0xeb) DW_TAG_formal_parameter)
+	.long	.LASF14	# DW_AT_name: "value"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x15	# DW_AT_decl_line
+	.byte	0xf	# DW_AT_decl_column
+	.long	0x25	# DW_AT_type
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 0
+	.uleb128 0x7	# (DIE (0xfa) DW_TAG_inlined_subroutine)
+	.long	0x114	# DW_AT_abstract_origin
+	.long	.LBB6	# DW_AT_low_pc
+	.long	.LBE6-.LBB6	# DW_AT_high_pc
+	.byte	0x1	# DW_AT_call_file (ptwrite.c)
+	.byte	0x17	# DW_AT_call_line
+	.byte	0x3	# DW_AT_call_column
+	.uleb128 0x8	# (DIE (0x10a) DW_TAG_formal_parameter)
+	.long	0x11e	# DW_AT_abstract_origin
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -12
+	.byte	0	# end of children of DIE 0xfa
+	.byte	0	# end of children of DIE 0xd5
+	.uleb128 0x9	# (DIE (0x114) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF19	# DW_AT_name: "_ptwrite32"
+	.byte	0x2	# DW_AT_decl_file (/usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h)
+	.value	0x131	# DW_AT_decl_line
+	.byte	0x1	# DW_AT_decl_column
+			# DW_AT_prototyped
+	.byte	0x3	# DW_AT_inline
+			# DW_AT_artificial
+	.uleb128 0xa	# (DIE (0x11e) DW_TAG_formal_parameter)
+	.ascii "__B\0"	# DW_AT_name
+	.byte	0x2	# DW_AT_decl_file (/usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h)
+	.value	0x131	# DW_AT_decl_line
+	.byte	0x16	# DW_AT_decl_column
+	.long	0x48	# DW_AT_type
+	.byte	0	# end of children of DIE 0x114
+	.byte	0	# end of children of DIE 0xb
+	.section	.debug_abbrev,"",@progbits
+.Ldebug_abbrev0:
+	.uleb128 0x1	# (abbrev code)
+	.uleb128 0x11	# (TAG: DW_TAG_compile_unit)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x25	# (DW_AT_producer)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x13	# (DW_AT_language)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x1b	# (DW_AT_comp_dir)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x6	# (DW_FORM_data4)
+	.uleb128 0x10	# (DW_AT_stmt_list)
+	.uleb128 0x17	# (DW_FORM_sec_offset)
+	.byte	0
+	.byte	0
+	.uleb128 0x2	# (abbrev code)
+	.uleb128 0x24	# (TAG: DW_TAG_base_type)
+	.byte	0	# DW_children_no
+	.uleb128 0xb	# (DW_AT_byte_size)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3e	# (DW_AT_encoding)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.byte	0
+	.byte	0
+	.uleb128 0x3	# (abbrev code)
+	.uleb128 0x24	# (TAG: DW_TAG_base_type)
+	.byte	0	# DW_children_no
+	.uleb128 0xb	# (DW_AT_byte_size)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3e	# (DW_AT_encoding)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.byte	0
+	.byte	0
+	.uleb128 0x4	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0	# DW_children_no
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x27	# (DW_AT_prototyped)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x6	# (DW_FORM_data4)
+	.uleb128 0x40	# (DW_AT_frame_base)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x2116	# (DW_AT_GNU_all_tail_call_sites)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.byte	0
+	.byte	0
+	.uleb128 0x5	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x27	# (DW_AT_prototyped)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x6	# (DW_FORM_data4)
+	.uleb128 0x40	# (DW_AT_frame_base)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x2117	# (DW_AT_GNU_all_call_sites)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.uleb128 0x6	# (abbrev code)
+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
+	.byte	0	# DW_children_no
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0x7	# (abbrev code)
+	.uleb128 0x1d	# (TAG: DW_TAG_inlined_subroutine)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x31	# (DW_AT_abstract_origin)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x6	# (DW_FORM_data4)
+	.uleb128 0x58	# (DW_AT_call_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x59	# (DW_AT_call_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x57	# (DW_AT_call_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.byte	0
+	.byte	0
+	.uleb128 0x8	# (abbrev code)
+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
+	.byte	0	# DW_children_no
+	.uleb128 0x31	# (DW_AT_abstract_origin)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0x9	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0x5	# (DW_FORM_data2)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x27	# (DW_AT_prototyped)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x20	# (DW_AT_inline)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x34	# (DW_AT_artificial)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.byte	0
+	.byte	0
+	.uleb128 0xa	# (abbrev code)
+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
+	.byte	0	# DW_children_no
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0x5	# (DW_FORM_data2)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.byte	0
+	.section	.debug_aranges,"",@progbits
+	.long	0x1c	# Length of Address Ranges Info
+	.value	0x2	# DWARF aranges version
+	.long	.Ldebug_info0	# Offset of Compilation Unit Info
+	.byte	0x4	# Size of Address
+	.byte	0	# Size of Segment Descriptor
+	.value	0	# Pad to 8 byte boundary
+	.value	0
+	.long	.Ltext0	# Address
+	.long	.Letext0-.Ltext0	# Length
+	.long	0
+	.long	0
+	.section	.debug_line,"",@progbits
+.Ldebug_line0:
+	.section	.debug_str,"MS",@progbits,1
+.LASF2:
+	.string	"long long int"
+.LASF14:
+	.string	"value"
+.LASF19:
+	.string	"_ptwrite32"
+.LASF4:
+	.string	"unsigned int"
+.LASF17:
+	.string	"gdb/gdb/testsuite/gdb.btrace"
+.LASF18:
+	.string	"main"
+.LASF16:
+	.string	"ptwrite.c"
+.LASF8:
+	.string	"long unsigned int"
+.LASF10:
+	.string	"long long unsigned int"
+.LASF13:
+	.string	"ptwrite1"
+.LASF12:
+	.string	"ptwrite2"
+.LASF6:
+	.string	"unsigned char"
+.LASF1:
+	.string	"char"
+.LASF5:
+	.string	"long int"
+.LASF15:
+	.string	"GNU C17 10.3.1 20210422 (Red Hat 10.3.1-1) -m32 -mptwrite -mtune=generic -march=i686 -g"
+.LASF11:
+	.string	"double"
+.LASF7:
+	.string	"short unsigned int"
+.LASF9:
+	.string	"signed char"
+.LASF3:
+	.string	"float"
+.LASF0:
+	.string	"short int"
+	.ident	"GCC: (GNU) 10.3.1 20210422 (Red Hat 10.3.1-1)"
+	.section	.note.GNU-stack,"",@progbits
diff --git a/gdb/testsuite/gdb.btrace/ptwrite.c b/gdb/testsuite/gdb.btrace/ptwrite.c
new file mode 100644
index 00000000000..efa9e97b7df
--- /dev/null
+++ b/gdb/testsuite/gdb.btrace/ptwrite.c
@@ -0,0 +1,39 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+ Copyright 2023 Free Software Foundation, Inc.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <immintrin.h>
+
+void
+ptwrite1 (int value)
+{
+  _ptwrite32 (value);
+}
+
+void
+ptwrite2 (int value)
+{
+  _ptwrite32 (value);
+}
+
+int
+main (void)
+{
+  ptwrite1 (0x42);
+  ptwrite2 (0x43);
+
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.btrace/ptwrite.exp b/gdb/testsuite/gdb.btrace/ptwrite.exp
new file mode 100644
index 00000000000..7878e7fc50d
--- /dev/null
+++ b/gdb/testsuite/gdb.btrace/ptwrite.exp
@@ -0,0 +1,202 @@
+# This testcase is part of GDB, the GNU debugger.
+#
+# Copyright 2023 Free Software Foundation, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+load_lib gdb-python.exp
+
+require allow_btrace_ptw_tests allow_python_tests
+
+set opts {}
+
+if [info exists COMPILE] {
+    # make check RUNTESTFLAGS="gdb.btrace/ptwrite.exp COMPILE=1"
+    standard_testfile ptwrite.c
+    lappend opts debug additional_flags=-mptwrite
+} elseif {[istarget "i?86-*-*"] || [istarget "x86_64-*-*"]} {
+    if {[is_amd64_regs_target]} {
+	standard_testfile x86_64-ptwrite.S
+    } else {
+	standard_testfile i386-ptwrite.S
+    }
+} else {
+    unsupported "target architecture not supported"
+    return -1
+}
+
+if [prepare_for_testing "failed to prepare" $testfile $srcfile $opts] {
+    return -1
+}
+
+if { ![runto_main] } {
+    untested "failed to run to main"
+    return -1
+}
+
+### 1. Default testrun
+
+# Setup recording
+gdb_test_no_output "set record instruction-history-size unlimited"
+gdb_test_no_output "record btrace pt"
+gdb_test "next" ".*" "next"
+gdb_test "next" ".*" "next 2"
+
+with_test_prefix "Default" {
+    # Test record instruction-history
+    gdb_test "record instruction-history 1" [multi_line \
+	".*\[0-9\]+\t   $hex <ptwrite1\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t   \\\[0x42\\\]" \
+	".*\[0-9\]+\t   $hex <ptwrite2\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t   \\\[0x43\\\].*" \
+	]
+
+    gdb_test "record instruction-history /a 1" [multi_line \
+	".*\[0-9\]+\t   $hex <ptwrite1\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	".*\[0-9\]+\t   $hex <ptwrite2\\+\[0-9\]+>:\tptwrite %\[a-z\]+.*" \
+	]
+
+    # Test function call history
+    gdb_test "record function-call-history 1,4" [multi_line \
+	"1\tmain" \
+	"2\tptwrite1" \
+	"\t\t\\\[0x42\\\]" \
+	"3\tmain" \
+	"4\tptwrite2" \
+	"\t\t\\\[0x43\\\]" \
+	]
+
+    gdb_test "record function-call-history /a 1,4" [multi_line \
+	"1\tmain" \
+	"2\tptwrite1" \
+	"3\tmain" \
+	"4\tptwrite2" \
+	]
+}
+
+# Test payload printing during stepping
+with_test_prefix "Stepping" {
+    gdb_test "record goto 10" "Can't go to an auxiliary instruction\."
+    gdb_test "record goto 9" ".*ptwrite.* at .*"
+    gdb_test "stepi" ".*\\\[0x42\\\].*"
+    gdb_test "reverse-stepi" ".*\\\[0x42\\\].*"
+    gdb_test "continue" [multi_line \
+	    ".*\\\[0x42\\\]" \
+	    "\\\[0x43\\\].*" \
+	    ]
+    gdb_test "reverse-continue" [multi_line \
+	    ".*\\\[0x43\\\]" \
+	    "\\\[0x42\\\].*" \
+	    ]
+}
+
+# Test auxiliary type in python
+gdb_test_multiline "auxiliary type in python" \
+    "python" "" \
+    "h = gdb.current_recording().instruction_history" "" \
+    "for insn in h:" "" \
+    "    if hasattr(insn, 'decoded'):" "" \
+    "        print(insn.decoded.decode())" "" \
+    "    elif hasattr(insn, 'data'):" "" \
+    "        print(insn.data)" "" \
+    "end" \
+    [multi_line \
+	".*mov    -0x4\\\(%(e|r)bp\\\),%(e|r)ax" \
+	"ptwrite %eax" \
+	"0x42" \
+	"nop.*" \
+	"mov    -0x4\\\(%(e|r)bp\\\),%(e|r)ax" \
+	"ptwrite %eax" \
+	"0x43" \
+	"nop.*"
+    ]
+
+
+### 2. Test filter registration
+### 2.1 Custom filter
+with_test_prefix "Custom" {
+    gdb_test_multiline "register filter in python" \
+	"python" "" \
+	"def my_filter(payload, ip):" "" \
+	"    if  payload == 66:" "" \
+	"        return \"payload: {0}, ip: {1:#x}\".format(payload, ip)" "" \
+	"    else:" "" \
+	"        return None" "" \
+	"def factory(thread): return my_filter" "" \
+	"import gdb.ptwrite" "" \
+	"gdb.ptwrite.register_filter_factory(factory)" "" \
+	"end" ""
+
+    gdb_test "record instruction-history 1" [multi_line \
+	".*\[0-9\]+\t   $hex <ptwrite1\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t   \\\[payload: 66, ip: $hex\\\]" \
+	".*\[0-9\]+\t   $hex <ptwrite2\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t   $hex <ptwrite2\\+\[0-9\]+>:.*" \
+	]
+}
+
+### 2.2 None as filter. This resets the default behaviour.
+with_test_prefix "None" {
+    gdb_test_multiline "register filter in python" \
+	"python" "" \
+	"import gdb.ptwrite" "" \
+	"gdb.ptwrite.register_filter_factory(None)" "" \
+	"end" ""
+
+    gdb_test "record instruction-history 1" [multi_line \
+	".*\[0-9\]+\t   $hex <ptwrite1\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t   \\\[0x42\\\]" \
+	".*\[0-9\]+\t   $hex <ptwrite2\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t   \\\[0x43\\\].*" \
+	]
+}
+
+### 2.3 Lambdas as filter
+with_test_prefix "Lambdas" {
+    gdb_test_multiline "register filter in python" \
+	"python" "" \
+	"import gdb.ptwrite" "" \
+	"lambda_filter = lambda payload, ip: \"{}\".format(payload + 2)" "" \
+	"gdb.ptwrite.register_filter_factory(lambda thread : lambda_filter)" "" \
+	"end" ""
+
+    gdb_test "record instruction-history 1" [multi_line \
+	".*\[0-9\]+\t   $hex <ptwrite1\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t   \\\[68\\\]" \
+	".*\[0-9\]+\t   $hex <ptwrite2\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t   \\\[69\\\].*" \
+	] "Lambdas: record instruction-history 1"
+}
+
+### 2.4 Functors as filter
+with_test_prefix "Functors" {
+    gdb_test_multiline "register filter in python" \
+	"python" "" \
+	"import gdb.ptwrite" "" \
+	"class foobar(object):" "" \
+	"    def __init__(self):" "" \
+	"        self.variable = 0" "" \
+	"    def __call__(self, payload, ip):" "" \
+	"        self.variable += 1" "" \
+	"        return \"{}, {}\".format(self.variable, payload)" "" \
+	"gdb.ptwrite.register_filter_factory(lambda thread : foobar())" "" \
+	"end" ""
+
+    gdb_test "record instruction-history 1" [multi_line \
+	".*\[0-9\]+\t   $hex <ptwrite1\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t   \\\[1, 66\\\]" \
+	".*\[0-9\]+\t   $hex <ptwrite2\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t   \\\[2, 67\\\].*" \
+	] "Functors: record instruction-history 1"
+}
diff --git a/gdb/testsuite/gdb.btrace/x86_64-ptwrite.S b/gdb/testsuite/gdb.btrace/x86_64-ptwrite.S
new file mode 100644
index 00000000000..a0840995104
--- /dev/null
+++ b/gdb/testsuite/gdb.btrace/x86_64-ptwrite.S
@@ -0,0 +1,544 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2023 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+   This file has been generated using gcc version 10.3.1 20210422
+   (Red Hat 10.3.1-1):
+   gcc -S -dA -g -mptwrite ptwrite.c -o x86_64-ptwrite.S.  */
+
+	.file	"ptwrite.c"
+	.text
+.Ltext0:
+	.globl	ptwrite1
+	.type	ptwrite1, @function
+ptwrite1:
+.LFB4096:
+	.file 1 "ptwrite.c"
+	# ptwrite.c:22:1
+	.loc 1 22 1
+	.cfi_startproc
+# BLOCK 2 seq:0
+# PRED: ENTRY (FALLTHRU)
+	pushq	%rbp
+	.cfi_def_cfa_offset 16
+	.cfi_offset 6, -16
+	movq	%rsp, %rbp
+	.cfi_def_cfa_register 6
+	movl	%edi, -20(%rbp)
+	# ptwrite.c:23:3
+	.loc 1 23 3
+	movl	-20(%rbp), %eax
+	movl	%eax, -4(%rbp)
+.LBB6:
+.LBB7:
+	.file 2 "/usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h"
+	# /usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h:307:3
+	.loc 2 307 3
+	movl	-4(%rbp), %eax
+	ptwrite	%eax
+	# /usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h:308:1
+	.loc 2 308 1
+	nop
+.LBE7:
+.LBE6:
+	# ptwrite.c:24:1
+	.loc 1 24 1
+	nop
+	popq	%rbp
+	.cfi_def_cfa 7, 8
+# SUCC: EXIT [always]
+	ret
+	.cfi_endproc
+.LFE4096:
+	.size	ptwrite1, .-ptwrite1
+	.globl	ptwrite2
+	.type	ptwrite2, @function
+ptwrite2:
+.LFB4097:
+	# ptwrite.c:28:1
+	.loc 1 28 1
+	.cfi_startproc
+# BLOCK 2 seq:0
+# PRED: ENTRY (FALLTHRU)
+	pushq	%rbp
+	.cfi_def_cfa_offset 16
+	.cfi_offset 6, -16
+	movq	%rsp, %rbp
+	.cfi_def_cfa_register 6
+	movl	%edi, -20(%rbp)
+	# ptwrite.c:29:3
+	.loc 1 29 3
+	movl	-20(%rbp), %eax
+	movl	%eax, -4(%rbp)
+.LBB8:
+.LBB9:
+	# /usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h:307:3
+	.loc 2 307 3
+	movl	-4(%rbp), %eax
+	ptwrite	%eax
+	# /usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h:308:1
+	.loc 2 308 1
+	nop
+.LBE9:
+.LBE8:
+	# ptwrite.c:30:1
+	.loc 1 30 1
+	nop
+	popq	%rbp
+	.cfi_def_cfa 7, 8
+# SUCC: EXIT [always]
+	ret
+	.cfi_endproc
+.LFE4097:
+	.size	ptwrite2, .-ptwrite2
+	.globl	main
+	.type	main, @function
+main:
+.LFB4098:
+	# ptwrite.c:34:1
+	.loc 1 34 1
+	.cfi_startproc
+# BLOCK 2 seq:0
+# PRED: ENTRY (FALLTHRU)
+	pushq	%rbp
+	.cfi_def_cfa_offset 16
+	.cfi_offset 6, -16
+	movq	%rsp, %rbp
+	.cfi_def_cfa_register 6
+	# ptwrite.c:35:3
+	.loc 1 35 3
+	movl	$66, %edi
+	call	ptwrite1
+	# ptwrite.c:36:3
+	.loc 1 36 3
+	movl	$67, %edi
+	call	ptwrite2
+	# ptwrite.c:38:10
+	.loc 1 38 10
+	movl	$0, %eax
+	# ptwrite.c:39:1
+	.loc 1 39 1
+	popq	%rbp
+	.cfi_def_cfa 7, 8
+# SUCC: EXIT [always]
+	ret
+	.cfi_endproc
+.LFE4098:
+	.size	main, .-main
+.Letext0:
+	.section	.debug_info,"",@progbits
+.Ldebug_info0:
+	.long	0x159	# Length of Compilation Unit Info
+	.value	0x4	# DWARF version number
+	.long	.Ldebug_abbrev0	# Offset Into Abbrev. Section
+	.byte	0x8	# Pointer Size (in bytes)
+	.uleb128 0x1	# (DIE (0xb) DW_TAG_compile_unit)
+	.long	.LASF15	# DW_AT_producer: "GNU C17 10.3.1 20210422 (Red Hat 10.3.1-1) -mptwrite -mtune=generic -march=x86-64 -g"
+	.byte	0xc	# DW_AT_language
+	.long	.LASF16	# DW_AT_name: "ptwrite.c"
+	.long	.LASF17	# DW_AT_comp_dir: "gdb/gdb/testsuite/gdb.btrace"
+	.quad	.Ltext0	# DW_AT_low_pc
+	.quad	.Letext0-.Ltext0	# DW_AT_high_pc
+	.long	.Ldebug_line0	# DW_AT_stmt_list
+	.uleb128 0x2	# (DIE (0x2d) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.ascii "int\0"	# DW_AT_name
+	.uleb128 0x3	# (DIE (0x34) DW_TAG_base_type)
+	.byte	0x2	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.long	.LASF0	# DW_AT_name: "short int"
+	.uleb128 0x3	# (DIE (0x3b) DW_TAG_base_type)
+	.byte	0x1	# DW_AT_byte_size
+	.byte	0x6	# DW_AT_encoding
+	.long	.LASF1	# DW_AT_name: "char"
+	.uleb128 0x3	# (DIE (0x42) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.long	.LASF2	# DW_AT_name: "long long int"
+	.uleb128 0x3	# (DIE (0x49) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x4	# DW_AT_encoding
+	.long	.LASF3	# DW_AT_name: "float"
+	.uleb128 0x3	# (DIE (0x50) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x7	# DW_AT_encoding
+	.long	.LASF4	# DW_AT_name: "long unsigned int"
+	.uleb128 0x3	# (DIE (0x57) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.long	.LASF5	# DW_AT_name: "long int"
+	.uleb128 0x3	# (DIE (0x5e) DW_TAG_base_type)
+	.byte	0x1	# DW_AT_byte_size
+	.byte	0x8	# DW_AT_encoding
+	.long	.LASF6	# DW_AT_name: "unsigned char"
+	.uleb128 0x3	# (DIE (0x65) DW_TAG_base_type)
+	.byte	0x2	# DW_AT_byte_size
+	.byte	0x7	# DW_AT_encoding
+	.long	.LASF7	# DW_AT_name: "short unsigned int"
+	.uleb128 0x3	# (DIE (0x6c) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x7	# DW_AT_encoding
+	.long	.LASF8	# DW_AT_name: "unsigned int"
+	.uleb128 0x3	# (DIE (0x73) DW_TAG_base_type)
+	.byte	0x1	# DW_AT_byte_size
+	.byte	0x6	# DW_AT_encoding
+	.long	.LASF9	# DW_AT_name: "signed char"
+	.uleb128 0x3	# (DIE (0x7a) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x7	# DW_AT_encoding
+	.long	.LASF10	# DW_AT_name: "long long unsigned int"
+	.uleb128 0x3	# (DIE (0x81) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x4	# DW_AT_encoding
+	.long	.LASF11	# DW_AT_name: "double"
+	.uleb128 0x4	# (DIE (0x88) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF18	# DW_AT_name: "main"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x21	# DW_AT_decl_line
+	.byte	0x1	# DW_AT_decl_column
+			# DW_AT_prototyped
+	.long	0x2d	# DW_AT_type
+	.quad	.LFB4098	# DW_AT_low_pc
+	.quad	.LFE4098-.LFB4098	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_tail_call_sites
+	.uleb128 0x5	# (DIE (0xa6) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF12	# DW_AT_name: "ptwrite2"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x1b	# DW_AT_decl_line
+	.byte	0x1	# DW_AT_decl_column
+			# DW_AT_prototyped
+	.quad	.LFB4097	# DW_AT_low_pc
+	.quad	.LFE4097-.LFB4097	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_call_sites
+	.long	0xf5	# DW_AT_sibling
+	.uleb128 0x6	# (DIE (0xc4) DW_TAG_formal_parameter)
+	.long	.LASF14	# DW_AT_name: "value"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x1b	# DW_AT_decl_line
+	.byte	0xf	# DW_AT_decl_column
+	.long	0x2d	# DW_AT_type
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -36
+	.uleb128 0x7	# (DIE (0xd3) DW_TAG_inlined_subroutine)
+	.long	0x144	# DW_AT_abstract_origin
+	.quad	.LBB8	# DW_AT_low_pc
+	.quad	.LBE8-.LBB8	# DW_AT_high_pc
+	.byte	0x1	# DW_AT_call_file (ptwrite.c)
+	.byte	0x1d	# DW_AT_call_line
+	.byte	0x3	# DW_AT_call_column
+	.uleb128 0x8	# (DIE (0xeb) DW_TAG_formal_parameter)
+	.long	0x14e	# DW_AT_abstract_origin
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -20
+	.byte	0	# end of children of DIE 0xd3
+	.byte	0	# end of children of DIE 0xa6
+	.uleb128 0x5	# (DIE (0xf5) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF13	# DW_AT_name: "ptwrite1"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x15	# DW_AT_decl_line
+	.byte	0x1	# DW_AT_decl_column
+			# DW_AT_prototyped
+	.quad	.LFB4096	# DW_AT_low_pc
+	.quad	.LFE4096-.LFB4096	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_call_sites
+	.long	0x144	# DW_AT_sibling
+	.uleb128 0x6	# (DIE (0x113) DW_TAG_formal_parameter)
+	.long	.LASF14	# DW_AT_name: "value"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x15	# DW_AT_decl_line
+	.byte	0xf	# DW_AT_decl_column
+	.long	0x2d	# DW_AT_type
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -36
+	.uleb128 0x7	# (DIE (0x122) DW_TAG_inlined_subroutine)
+	.long	0x144	# DW_AT_abstract_origin
+	.quad	.LBB6	# DW_AT_low_pc
+	.quad	.LBE6-.LBB6	# DW_AT_high_pc
+	.byte	0x1	# DW_AT_call_file (ptwrite.c)
+	.byte	0x17	# DW_AT_call_line
+	.byte	0x3	# DW_AT_call_column
+	.uleb128 0x8	# (DIE (0x13a) DW_TAG_formal_parameter)
+	.long	0x14e	# DW_AT_abstract_origin
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -20
+	.byte	0	# end of children of DIE 0x122
+	.byte	0	# end of children of DIE 0xf5
+	.uleb128 0x9	# (DIE (0x144) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF19	# DW_AT_name: "_ptwrite32"
+	.byte	0x2	# DW_AT_decl_file (/usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h)
+	.value	0x131	# DW_AT_decl_line
+	.byte	0x1	# DW_AT_decl_column
+			# DW_AT_prototyped
+	.byte	0x3	# DW_AT_inline
+			# DW_AT_artificial
+	.uleb128 0xa	# (DIE (0x14e) DW_TAG_formal_parameter)
+	.ascii "__B\0"	# DW_AT_name
+	.byte	0x2	# DW_AT_decl_file (/usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h)
+	.value	0x131	# DW_AT_decl_line
+	.byte	0x16	# DW_AT_decl_column
+	.long	0x6c	# DW_AT_type
+	.byte	0	# end of children of DIE 0x144
+	.byte	0	# end of children of DIE 0xb
+	.section	.debug_abbrev,"",@progbits
+.Ldebug_abbrev0:
+	.uleb128 0x1	# (abbrev code)
+	.uleb128 0x11	# (TAG: DW_TAG_compile_unit)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x25	# (DW_AT_producer)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x13	# (DW_AT_language)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x1b	# (DW_AT_comp_dir)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x7	# (DW_FORM_data8)
+	.uleb128 0x10	# (DW_AT_stmt_list)
+	.uleb128 0x17	# (DW_FORM_sec_offset)
+	.byte	0
+	.byte	0
+	.uleb128 0x2	# (abbrev code)
+	.uleb128 0x24	# (TAG: DW_TAG_base_type)
+	.byte	0	# DW_children_no
+	.uleb128 0xb	# (DW_AT_byte_size)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3e	# (DW_AT_encoding)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.byte	0
+	.byte	0
+	.uleb128 0x3	# (abbrev code)
+	.uleb128 0x24	# (TAG: DW_TAG_base_type)
+	.byte	0	# DW_children_no
+	.uleb128 0xb	# (DW_AT_byte_size)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3e	# (DW_AT_encoding)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.byte	0
+	.byte	0
+	.uleb128 0x4	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0	# DW_children_no
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x27	# (DW_AT_prototyped)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x7	# (DW_FORM_data8)
+	.uleb128 0x40	# (DW_AT_frame_base)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x2116	# (DW_AT_GNU_all_tail_call_sites)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.byte	0
+	.byte	0
+	.uleb128 0x5	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x27	# (DW_AT_prototyped)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x7	# (DW_FORM_data8)
+	.uleb128 0x40	# (DW_AT_frame_base)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x2117	# (DW_AT_GNU_all_call_sites)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.uleb128 0x6	# (abbrev code)
+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
+	.byte	0	# DW_children_no
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0x7	# (abbrev code)
+	.uleb128 0x1d	# (TAG: DW_TAG_inlined_subroutine)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x31	# (DW_AT_abstract_origin)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x7	# (DW_FORM_data8)
+	.uleb128 0x58	# (DW_AT_call_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x59	# (DW_AT_call_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x57	# (DW_AT_call_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.byte	0
+	.byte	0
+	.uleb128 0x8	# (abbrev code)
+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
+	.byte	0	# DW_children_no
+	.uleb128 0x31	# (DW_AT_abstract_origin)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0x9	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0x5	# (DW_FORM_data2)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x27	# (DW_AT_prototyped)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x20	# (DW_AT_inline)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x34	# (DW_AT_artificial)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.byte	0
+	.byte	0
+	.uleb128 0xa	# (abbrev code)
+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
+	.byte	0	# DW_children_no
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0x5	# (DW_FORM_data2)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.byte	0
+	.section	.debug_aranges,"",@progbits
+	.long	0x2c	# Length of Address Ranges Info
+	.value	0x2	# DWARF aranges version
+	.long	.Ldebug_info0	# Offset of Compilation Unit Info
+	.byte	0x8	# Size of Address
+	.byte	0	# Size of Segment Descriptor
+	.value	0	# Pad to 16 byte boundary
+	.value	0
+	.quad	.Ltext0	# Address
+	.quad	.Letext0-.Ltext0	# Length
+	.quad	0
+	.quad	0
+	.section	.debug_line,"",@progbits
+.Ldebug_line0:
+	.section	.debug_str,"MS",@progbits,1
+.LASF2:
+	.string	"long long int"
+.LASF14:
+	.string	"value"
+.LASF19:
+	.string	"_ptwrite32"
+.LASF8:
+	.string	"unsigned int"
+.LASF17:
+	.string	"gdb/gdb/testsuite/gdb.btrace"
+.LASF18:
+	.string	"main"
+.LASF16:
+	.string	"ptwrite.c"
+.LASF4:
+	.string	"long unsigned int"
+.LASF10:
+	.string	"long long unsigned int"
+.LASF15:
+	.string	"GNU C17 10.3.1 20210422 (Red Hat 10.3.1-1) -mptwrite -mtune=generic -march=x86-64 -g"
+.LASF13:
+	.string	"ptwrite1"
+.LASF12:
+	.string	"ptwrite2"
+.LASF6:
+	.string	"unsigned char"
+.LASF1:
+	.string	"char"
+.LASF5:
+	.string	"long int"
+.LASF11:
+	.string	"double"
+.LASF7:
+	.string	"short unsigned int"
+.LASF9:
+	.string	"signed char"
+.LASF3:
+	.string	"float"
+.LASF0:
+	.string	"short int"
+	.ident	"GCC: (GNU) 10.3.1 20210422 (Red Hat 10.3.1-1)"
+	.section	.note.GNU-stack,"",@progbits
diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp
index 66c04a2efe2..df018f302c4 100644
--- a/gdb/testsuite/lib/gdb.exp
+++ b/gdb/testsuite/lib/gdb.exp
@@ -4074,6 +4074,78 @@ gdb_caching_proc allow_btrace_pt_tests {} {
     return $allow_btrace_pt_tests
 }
 
+# Run a test on the target to see if it supports ptwrite instructions and
+# if GDB can decode ptwrite events.  Return 1 if so, 0 if it does not.
+
+gdb_caching_proc allow_btrace_ptw_tests {} {
+    global srcdir subdir gdb_prompt inferior_exited_re decimal
+
+    require allow_btrace_pt_tests
+    set me "allow_btrace_ptw_tests"
+
+    set src {
+	int
+	main ()
+	{
+	  asm volatile ("PTWRITE %0;" : : "b"(0x42));
+	  return 0;
+	}
+    }
+
+    if {![gdb_simple_compile $me $src executable]} {
+	return 1
+    }
+
+    gdb_exit
+    gdb_start
+    gdb_reinitialize_dir $srcdir/$subdir
+    gdb_load "$obj"
+    if ![runto_main] {
+	return 1
+    }
+
+    gdb_test_no_output "record btrace pt" "$me: record btrace pt"
+
+    set allow_btrace_ptw_tests 2
+    gdb_test_multiple "next" "$me: next" {
+	-re -wrap ".*Illegal instruction.*" {
+	    verbose -log "$me:  ptwrite instruction support not detected."
+	    set allow_btrace_ptw_tests 0
+	}
+	-re -wrap ".*$inferior_exited_re normally.*" {
+	    verbose -log "$me:  ptwrite support not detected."
+	    set allow_btrace_ptw_tests 0
+	}
+	-re -wrap "$decimal.*(at|in|return 0).*" {
+	    set allow_btrace_ptw_tests 1
+	}
+    }
+
+    if { $allow_btrace_ptw_tests == 1 } {
+	# Show the func-call-history to get the packet trace.
+	gdb_test "record function-call-history" ".*"
+
+	gdb_test_multiple "maintenance btrace packet-history 0,1000" \
+	    "$me: check decoding support" {
+	    -re  "ptw" {
+		verbose -log "$me:  ptwrite decoding support detected."
+		set allow_btrace_ptw_tests 1
+	    }
+	    -re ".*${gdb_prompt} $" {
+		verbose -log "$me:  ptwrite decoding support not detected."
+		set allow_btrace_ptw_tests 0
+	    }
+	}
+    }
+
+    gdb_exit
+    remote_file build delete $obj
+
+    verbose "$me:  returning $allow_btrace_ptw_tests" 2
+    return $allow_btrace_ptw_tests
+}
+
+
 # Run a test on the target to see if it supports Aarch64 SVE hardware.
 # Return 1 if so, 0 if it does not.  Note this causes a restart of GDB.
 
diff --git a/gdbsupport/common.m4 b/gdbsupport/common.m4
index 3909ec81ccb..1ad2395e80f 100644
--- a/gdbsupport/common.m4
+++ b/gdbsupport/common.m4
@@ -190,6 +190,8 @@ AC_DEFUN([GDB_AC_COMMON], [
       AC_CHECK_FUNCS(pt_insn_event)
       AC_CHECK_MEMBERS([struct pt_insn.enabled, struct pt_insn.resynced], [], [],
 		       [#include <intel-pt.h>])
+      AC_CHECK_MEMBERS([struct pt_event.variant.ptwrite], [], [],
+		       [#include <intel-pt.h>])
       LIBS=$save_LIBS
     fi
   fi
diff --git a/gdbsupport/config.in b/gdbsupport/config.in
index 2cdc1fbde61..8ce8e23bc24 100644
--- a/gdbsupport/config.in
+++ b/gdbsupport/config.in
@@ -238,6 +238,9 @@
 /* Define to 1 if you have the <string.h> header file. */
 #undef HAVE_STRING_H
 
+/* Define to 1 if `variant.ptwrite' is a member of `struct pt_event'. */
+#undef HAVE_STRUCT_PT_EVENT_VARIANT_PTWRITE
+
 /* Define to 1 if `enabled' is a member of `struct pt_insn'. */
 #undef HAVE_STRUCT_PT_INSN_ENABLED
 
diff --git a/gdbsupport/configure b/gdbsupport/configure
index 9433ac41468..7a10c96bd75 100755
--- a/gdbsupport/configure
+++ b/gdbsupport/configure
@@ -9625,6 +9625,17 @@ cat >>confdefs.h <<_ACEOF
 _ACEOF
 
 
+fi
+
+      ac_fn_c_check_member "$LINENO" "struct pt_event" "variant.ptwrite" "ac_cv_member_struct_pt_event_variant_ptwrite" "#include <intel-pt.h>
+"
+if test "x$ac_cv_member_struct_pt_event_variant_ptwrite" = xyes; then :
+
+cat >>confdefs.h <<_ACEOF
+#define HAVE_STRUCT_PT_EVENT_VARIANT_PTWRITE 1
+_ACEOF
+
+
 fi
 
       LIBS=$save_LIBS
-- 
2.34.1

Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

Re: [PATCH v10 06/10] python: Add clear() to gdb.Record.

[Eli Zaretskii]

> Date: Tue, 18 Jul 2023 13:56:33 +0200
> From: Felix Willgerodt via Gdb-patches <gdb-patches@sourceware.org>
> 
> This function allows to clear the trace data from python, forcing to
> re-decode the trace for successive commands.
> This will be used in future ptwrite patches, to trigger re-decoding when
> the ptwrite filter changes.
> 
> Reviewed-By: Eli Zaretskii <eliz@gnu.org>
> ---
>  gdb/NEWS                                      |  3 +++
>  gdb/doc/python.texi                           |  5 +++++
>  gdb/python/py-record-btrace.c                 | 13 +++++++++++++
>  gdb/python/py-record-btrace.h                 |  3 +++
>  gdb/python/py-record.c                        | 16 ++++++++++++++++
>  gdb/testsuite/gdb.python/py-record-btrace.exp |  4 ++++
>  6 files changed, 44 insertions(+)

The NEWS part (which AFAIU is the only change in v10,
documentation-wise) is OK.  Thanks.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>

Re: [PATCH v10 10/10] btrace: Extend ptwrite event decoding.

[Eli Zaretskii]

> Date: Tue, 18 Jul 2023 13:56:37 +0200
> From: Felix Willgerodt via Gdb-patches <gdb-patches@sourceware.org>
> 
> Call the ptwrite filter function whenever a ptwrite event is decoded.
> The returned string is written to the aux_data string table and a
> corresponding auxiliary instruction is appended to the function segment.
> 
> Reviewed-By: Eli Zaretskii <eliz@gnu.org>
> ---
>  gdb/NEWS                                  |   7 +
>  gdb/btrace.c                              |  58 +++
>  gdb/config.in                             |   3 +
>  gdb/configure                             |  11 +
>  gdb/doc/python.texi                       | 149 ++++++
>  gdb/testsuite/gdb.btrace/i386-ptwrite.S   | 550 ++++++++++++++++++++++
>  gdb/testsuite/gdb.btrace/ptwrite.c        |  39 ++
>  gdb/testsuite/gdb.btrace/ptwrite.exp      | 202 ++++++++
>  gdb/testsuite/gdb.btrace/x86_64-ptwrite.S | 544 +++++++++++++++++++++
>  gdb/testsuite/lib/gdb.exp                 |  72 +++
>  gdbsupport/common.m4                      |   2 +
>  gdbsupport/config.in                      |   3 +
>  gdbsupport/configure                      |  11 +
>  13 files changed, 1651 insertions(+)
>  create mode 100644 gdb/testsuite/gdb.btrace/i386-ptwrite.S
>  create mode 100644 gdb/testsuite/gdb.btrace/ptwrite.c
>  create mode 100644 gdb/testsuite/gdb.btrace/ptwrite.exp
>  create mode 100644 gdb/testsuite/gdb.btrace/x86_64-ptwrite.S

The NEWS part is OK (the rest hasn't changed since v9, AFAIU).

Thanks.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>

RE: [PATCH v10 05/10] python: Introduce gdb.RecordAuxiliary class.

[Metzger, Markus T]

Hello Felix,

>-  btrace_find_insn_by_number (&iter, &tinfo->btrace, number);
>+  if (btrace_find_insn_by_number (&iter, &tinfo->btrace, number) == 0)

Nit: how about storing the result in a local variable to avoid side-effects
in the if expression?

>+  if (Py_TYPE (self) != &recpy_aux_type)
>+    {
>+      PyErr_Format (gdbpy_gdb_error, _("Must be a gdb.Auxiliary."));
>+      return NULL;
>+    }
>+
>+  obj = (const recpy_element_object *) self;
>+  tinfo = obj->thread;
>+
>+  if (tinfo == NULL || btrace_is_empty (tinfo))
>+    {
>+      PyErr_Format (gdbpy_gdb_error, _("No such auxiliary object."));
>+      return NULL;
>+    }
>+
>+  if (btrace_find_insn_by_number (&iter, &tinfo->btrace, obj->number) == 0)
>+    {
>+      PyErr_Format (gdbpy_gdb_error, _("No such auxiliary object."));
>+      return NULL;
>+    }
>+
>+  insn = btrace_insn_get (&iter);
>+  if (insn == NULL)
>+    {
>+      PyErr_Format (gdbpy_gdb_error, _("Not a valid auxiliary object."));
>+      return NULL;
>+    }
>+
>+  return PyUnicode_FromString
>+    (iter.btinfo->aux_data.at (insn->aux_data_index).c_str ());

Shouldn't we check the insn class, too?


>@@ -455,10 +511,10 @@ btpy_list_item (PyObject *self, Py_ssize_t index)
>
>   number = obj->first + (obj->step * index);
>
>-  if (obj->element_type == &recpy_insn_type)
>-    return recpy_insn_new (obj->thread, RECORD_METHOD_BTRACE, number);
>-  else
>+  if (obj->element_type == &recpy_func_type)
>     return recpy_func_new (obj->thread, RECORD_METHOD_BTRACE, number);
>+  else
>+    return btpy_item_new (obj->thread, number);
> }

Why do we need to change the order?


Regards,
Markus.
Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

RE: [PATCH v10 08/10] btrace, linux: Enable ptwrite packets.

[Metzger, Markus T]

Hello Felix,

>+/* Read config bits.  */
>+
>+static bool
>+linux_read_pt_config_bit (const std::string &feature, uint64_t *config_bit)

This isn't really necessary since the bit resembles the enable bit in the control MSR.
It also doesn't hurt so I'm OK with the change.

>+{
>+  std::string filename
>+      = "/sys/bus/event_source/devices/intel_pt/format/" + feature;
>+  gdb_file_up file = gdb_fopen_cloexec (filename.c_str (), "r");
>+
>+  if (file.get () == nullptr || config_bit == nullptr)
>+    return false;

We could check CONFIG_BIT before opening the file.

>+
>+  int found = fscanf (file.get (), "config:%lu", config_bit);

The format string doesn't match the type.  We should use SCNu64.

>+  if (found != 1)
>+    {
>+      warning (_("Failed to determine config bit from %s."),
>+	       filename.c_str ());

The issue is that the file didn't contain the expected content.
This will probably need some changes in GDB to fix.  Could we
print the actual content and what we expected?


>+/* Check whether the linux target supports Intel Processor Trace PTWRITE.  */
>+
>+static bool
>+linux_supports_ptwrite (uint64_t *config_bit)
>+{
>+  static const char filename[]
>+      = "/sys/bus/event_source/devices/intel_pt/caps/ptwrite";
>+  gdb_file_up file = gdb_fopen_cloexec (filename, "r");
>+
>+  if (file.get () == nullptr)
>+    return false;
>+
>+  int status, found = fscanf (file.get (), "%d", &status);
>+
>+  if (found != 1)
>+    {
>+      warning (_("Failed to determine ptwrite support from %s."), filename);
>+      return false;
>+    }
>+
>+  if (!linux_read_pt_config_bit ("ptw", config_bit))

We should check STATUS before.  If caps indicates that ptwrite isn't
available, I'm not sure format will contain the bit position for enabling
it.

>+  uint64_t config_bit;
>+  if (conf->ptwrite && linux_supports_ptwrite (&config_bit))
>+    {
>+      pt->attr.config |= 1 << config_bit;
>+      tinfo->conf.pt.ptwrite = conf->ptwrite;
>+    }
>+
>   errno = 0;
>   scoped_fd fd (syscall (SYS_perf_event_open, &pt->attr, pid, -1, -1, 0));
>   if (fd.get () < 0)
>diff --git a/gdb/record-btrace.c b/gdb/record-btrace.c
>index c93b3d7c8de..ad3160d42c5 100644
>--- a/gdb/record-btrace.c
>+++ b/gdb/record-btrace.c
>@@ -3295,4 +3295,9 @@ to see the actual buffer size."), NULL,
>show_record_pt_buffer_size_value,
>
>   record_btrace_conf.bts.size = 64 * 1024;
>   record_btrace_conf.pt.size = 16 * 1024;
>+#if (LIBIPT_VERSION >= 0x200)
>+  record_btrace_conf.pt.ptwrite = true;
>+#else
>+  record_btrace_conf.pt.ptwrite = false;
>+#endif

Is there a way to get an error when attempting to install a custom
ptwrite filter when either GDB (via libipt) or the kernel does not
support PTWRITE?

Regards,
Markus.
Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

RE: [PATCH v10 05/10] python: Introduce gdb.RecordAuxiliary class.

[Willgerodt, Felix]

> -----Original Message-----
> From: Metzger, Markus T <markus.t.metzger@intel.com>
> Sent: Dienstag, 25. Juli 2023 15:30
> To: Willgerodt, Felix <felix.willgerodt@intel.com>; gdb-patches@sourceware.org;
> simark@simark.ca
> Subject: RE: [PATCH v10 05/10] python: Introduce gdb.RecordAuxiliary class.
> 
> Hello Felix,
> 
> >-  btrace_find_insn_by_number (&iter, &tinfo->btrace, number);
> >+  if (btrace_find_insn_by_number (&iter, &tinfo->btrace, number) == 0)
> 
> Nit: how about storing the result in a local variable to avoid side-effects
> in the if expression?

What side effects do you have in mind? I checked the function and couldn't find
any. And I just copied this from the existing btrace_insn_from_recpy_insn.

> >+  if (Py_TYPE (self) != &recpy_aux_type)
> >+    {
> >+      PyErr_Format (gdbpy_gdb_error, _("Must be a gdb.Auxiliary."));
> >+      return NULL;
> >+    }
> >+
> >+  obj = (const recpy_element_object *) self;
> >+  tinfo = obj->thread;
> >+
> >+  if (tinfo == NULL || btrace_is_empty (tinfo))
> >+    {
> >+      PyErr_Format (gdbpy_gdb_error, _("No such auxiliary object."));
> >+      return NULL;
> >+    }
> >+
> >+  if (btrace_find_insn_by_number (&iter, &tinfo->btrace, obj->number) == 0)
> >+    {
> >+      PyErr_Format (gdbpy_gdb_error, _("No such auxiliary object."));
> >+      return NULL;
> >+    }
> >+
> >+  insn = btrace_insn_get (&iter);
> >+  if (insn == NULL)
> >+    {
> >+      PyErr_Format (gdbpy_gdb_error, _("Not a valid auxiliary object."));
> >+      return NULL;
> >+    }
> >+
> >+  return PyUnicode_FromString
> >+    (iter.btinfo->aux_data.at (insn->aux_data_index).c_str ());
> 
> Shouldn't we check the insn class, too?

We checked the python object type above already.
So this would only catch cases in which something went horribly wrong
and the python trace doesn't match the internal trace.
I think right now that can never be the case, but it might be a good
sanity check, so I will add it.

> 
> >@@ -455,10 +511,10 @@ btpy_list_item (PyObject *self, Py_ssize_t index)
> >
> >   number = obj->first + (obj->step * index);
> >
> >-  if (obj->element_type == &recpy_insn_type)
> >-    return recpy_insn_new (obj->thread, RECORD_METHOD_BTRACE, number);
> >-  else
> >+  if (obj->element_type == &recpy_func_type)
> >     return recpy_func_new (obj->thread, RECORD_METHOD_BTRACE, number);
> >+  else
> >+    return btpy_item_new (obj->thread, number);
> > }
> 
> Why do we need to change the order?

Because we no longer call recpy_insn_new only for recpy_insn_type but also for
recpy_aux_type.

Regards,
Felix

 


Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

RE: [PATCH v10 08/10] btrace, linux: Enable ptwrite packets.

[Willgerodt, Felix]

> -----Original Message-----
> From: Metzger, Markus T <markus.t.metzger@intel.com>
> Sent: Dienstag, 25. Juli 2023 15:30
> To: Willgerodt, Felix <felix.willgerodt@intel.com>; gdb-patches@sourceware.org;
> simark@simark.ca
> Subject: RE: [PATCH v10 08/10] btrace, linux: Enable ptwrite packets.
> 
> Hello Felix,
> 
> >+/* Read config bits.  */
> >+
> >+static bool
> >+linux_read_pt_config_bit (const std::string &feature, uint64_t *config_bit)
> 
> This isn't really necessary since the bit resembles the enable bit in the control
> MSR.
> It also doesn't hurt so I'm OK with the change.

I was thinking to re-use this function for future features, like event tracing.
I didn't really dig into Linux code, I just felt that if there is a file for it lets read it.

> >+{
> >+  std::string filename
> >+      = "/sys/bus/event_source/devices/intel_pt/format/" + feature;
> >+  gdb_file_up file = gdb_fopen_cloexec (filename.c_str (), "r");
> >+
> >+  if (file.get () == nullptr || config_bit == nullptr)
> >+    return false;
> 
> We could check CONFIG_BIT before opening the file.

Will do.

> >+
> >+  int found = fscanf (file.get (), "config:%lu", config_bit);
> 
> The format string doesn't match the type.  We should use SCNu64.

Will do.

> >+  if (found != 1)
> >+    {
> >+      warning (_("Failed to determine config bit from %s."),
> >+	       filename.c_str ());
> 
> The issue is that the file didn't contain the expected content.
> This will probably need some changes in GDB to fix.  Could we
> print the actual content and what we expected?

Yes, this could mean that the format changed. But it could also
just be a corrupcted files/system.
I don't think we want to dump the content of a possibly corrupt file.


> >+/* Check whether the linux target supports Intel Processor Trace PTWRITE.  */
> >+
> >+static bool
> >+linux_supports_ptwrite (uint64_t *config_bit)
> >+{
> >+  static const char filename[]
> >+      = "/sys/bus/event_source/devices/intel_pt/caps/ptwrite";
> >+  gdb_file_up file = gdb_fopen_cloexec (filename, "r");
> >+
> >+  if (file.get () == nullptr)
> >+    return false;
> >+
> >+  int status, found = fscanf (file.get (), "%d", &status);
> >+
> >+  if (found != 1)
> >+    {
> >+      warning (_("Failed to determine ptwrite support from %s."), filename);
> >+      return false;
> >+    }
> >+
> >+  if (!linux_read_pt_config_bit ("ptw", config_bit))
> 
> We should check STATUS before.  If caps indicates that ptwrite isn't
> available, I'm not sure format will contain the bit position for enabling
> it.

Makes sense, I will do that.

> >+  uint64_t config_bit;
> >+  if (conf->ptwrite && linux_supports_ptwrite (&config_bit))
> >+    {
> >+      pt->attr.config |= 1 << config_bit;
> >+      tinfo->conf.pt.ptwrite = conf->ptwrite;
> >+    }
> >+
> >   errno = 0;
> >   scoped_fd fd (syscall (SYS_perf_event_open, &pt->attr, pid, -1, -1, 0));
> >   if (fd.get () < 0)
> >diff --git a/gdb/record-btrace.c b/gdb/record-btrace.c
> >index c93b3d7c8de..ad3160d42c5 100644
> >--- a/gdb/record-btrace.c
> >+++ b/gdb/record-btrace.c
> >@@ -3295,4 +3295,9 @@ to see the actual buffer size."), NULL,
> >show_record_pt_buffer_size_value,
> >
> >   record_btrace_conf.bts.size = 64 * 1024;
> >   record_btrace_conf.pt.size = 16 * 1024;
> >+#if (LIBIPT_VERSION >= 0x200)
> >+  record_btrace_conf.pt.ptwrite = true;
> >+#else
> >+  record_btrace_conf.pt.ptwrite = false;
> >+#endif
> 
> Is there a way to get an error when attempting to install a custom
> ptwrite filter when either GDB (via libipt) or the kernel does not
> support PTWRITE?

Good point. Unfortunately I don't see one with the current design.
Currently we just cache the filter functions in python when one is
registered. The configuration isn't exposed to the python layer in
any way.

I am not sure how we could do this. Exposing "maint btrace info"
and parsing that would be one way, not sure if we want to go down
that path.

Thanks,
Felix
Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

RE: [PATCH v10 05/10] python: Introduce gdb.RecordAuxiliary class.

[Metzger, Markus T]

Hello Felix,

>> >@@ -455,10 +511,10 @@ btpy_list_item (PyObject *self, Py_ssize_t index)
>> >
>> >   number = obj->first + (obj->step * index);
>> >
>> >-  if (obj->element_type == &recpy_insn_type)
>> >-    return recpy_insn_new (obj->thread, RECORD_METHOD_BTRACE, number);
>> >-  else
>> >+  if (obj->element_type == &recpy_func_type)
>> >     return recpy_func_new (obj->thread, RECORD_METHOD_BTRACE, number);
>> >+  else
>> >+    return btpy_item_new (obj->thread, number);
>> > }
>>
>> Why do we need to change the order?
>
>Because we no longer call recpy_insn_new only for recpy_insn_type but also for
>recpy_aux_type.

I think it would be clearer if we checked each type separately and errored
out by default.  Like a switch.

Regards,
Markus.
Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

RE: [PATCH v10 08/10] btrace, linux: Enable ptwrite packets.

[Metzger, Markus T]

Hello Felix,

>> >+#if (LIBIPT_VERSION >= 0x200)
>> >+  record_btrace_conf.pt.ptwrite = true;
>> >+#else
>> >+  record_btrace_conf.pt.ptwrite = false;
>> >+#endif
>>
>> Is there a way to get an error when attempting to install a custom
>> ptwrite filter when either GDB (via libipt) or the kernel does not
>> support PTWRITE?
>
>Good point. Unfortunately I don't see one with the current design.
>Currently we just cache the filter functions in python when one is
>registered. The configuration isn't exposed to the python layer in
>any way.
>
>I am not sure how we could do this. Exposing "maint btrace info"
>and parsing that would be one way, not sure if we want to go down
>that path.

We could warn at decode-time when applying the ptwrite filter.
We should have different warning texts for GDB (via libipt) not
supporting ptwrite and the system (kernel or h/w) not supporting it.

Not as good as an error when installing the ptwrite filter but better
than wondering why it isn't working as expected.

Regards,
Markus.
Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

RE: [PATCH v10 08/10] btrace, linux: Enable ptwrite packets.

[Willgerodt, Felix]

> -----Original Message-----
> From: Metzger, Markus T <markus.t.metzger@intel.com>
> Sent: Dienstag, 8. August 2023 12:13
> To: Willgerodt, Felix <felix.willgerodt@intel.com>
> Cc: gdb-patches@sourceware.org; simark@simark.ca
> Subject: RE: [PATCH v10 08/10] btrace, linux: Enable ptwrite packets.
> 
> Hello Felix,
> 
> >> >+#if (LIBIPT_VERSION >= 0x200)
> >> >+  record_btrace_conf.pt.ptwrite = true;
> >> >+#else
> >> >+  record_btrace_conf.pt.ptwrite = false;
> >> >+#endif
> >>
> >> Is there a way to get an error when attempting to install a custom
> >> ptwrite filter when either GDB (via libipt) or the kernel does not
> >> support PTWRITE?
> >
> >Good point. Unfortunately I don't see one with the current design.
> >Currently we just cache the filter functions in python when one is
> >registered. The configuration isn't exposed to the python layer in
> >any way.
> >
> >I am not sure how we could do this. Exposing "maint btrace info"
> >and parsing that would be one way, not sure if we want to go down
> >that path.
> 
> We could warn at decode-time when applying the ptwrite filter.
> We should have different warning texts for GDB (via libipt) not
> supporting ptwrite and the system (kernel or h/w) not supporting it.
> 
> Not as good as an error when installing the ptwrite filter but better
> than wondering why it isn't working as expected.

Mhm, I don't see this either. We can't warn when we actually would
apply the filter, as we never would get a ptwrite event. As we don't
enable ptwrite in Linux if libipt doesn't support it.  And if libipt doesn't
support it, we wouldn't get to that place in GDB in the first place,
as there is an #ifdef protecting it.

I looked at doing it when installing the extension language callback
for ptwrite in btrace.c, e.g. something similar to this:

  /* Register the ptwrite filter.  */
  if (btinfo->target->conf.pt.ptwrite)
	apply_ext_lang_ptwrite_filter (btinfo);
  else
    warning (_("Can't decode ptwrite events."));

This we do regardless of libipt. But then we would get a warning
regardless of the user trying to use ptwrite or not (with old libipt
versions). Plus this doesn't compile, as struct btrace_target_info
is forward declared, and we probably can't change that as btrace.c
should be target independent. 

Felix 
Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

RE: [PATCH v10 05/10] python: Introduce gdb.RecordAuxiliary class.

[Willgerodt, Felix]

> >> >@@ -455,10 +511,10 @@ btpy_list_item (PyObject *self, Py_ssize_t index)
> >> >
> >> >   number = obj->first + (obj->step * index);
> >> >
> >> >-  if (obj->element_type == &recpy_insn_type)
> >> >-    return recpy_insn_new (obj->thread, RECORD_METHOD_BTRACE,
> number);
> >> >-  else
> >> >+  if (obj->element_type == &recpy_func_type)
> >> >     return recpy_func_new (obj->thread, RECORD_METHOD_BTRACE,
> number);
> >> >+  else
> >> >+    return btpy_item_new (obj->thread, number);
> >> > }
> >>
> >> Why do we need to change the order?
> >
> >Because we no longer call recpy_insn_new only for recpy_insn_type but also for
> >recpy_aux_type.
> 
> I think it would be clearer if we checked each type separately and errored
> out by default.  Like a switch.

I can put something like this:

  if (obj->element_type == &recpy_func_type)
    return recpy_func_new (obj->thread, RECORD_METHOD_BTRACE, number);
  else if (obj->element_type == &recpy_insn_type
	   || obj->element_type == &recpy_aux_type)
    return btpy_item_new (obj->thread, number);
  else
    return PyErr_Format (gdbpy_gdb_error, _("Not a valid BtraceList object."));

I don't think we can reach the error case right now though.

Felix



Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

RE: [PATCH v10 08/10] btrace, linux: Enable ptwrite packets.

[Metzger, Markus T]

Hello Felix,

>> >> >+#if (LIBIPT_VERSION >= 0x200)
>> >> >+  record_btrace_conf.pt.ptwrite = true;
>> >> >+#else
>> >> >+  record_btrace_conf.pt.ptwrite = false;
>> >> >+#endif
>> >>
>> >> Is there a way to get an error when attempting to install a custom
>> >> ptwrite filter when either GDB (via libipt) or the kernel does not
>> >> support PTWRITE?
>> >
>> >Good point. Unfortunately I don't see one with the current design.
>> >Currently we just cache the filter functions in python when one is
>> >registered. The configuration isn't exposed to the python layer in
>> >any way.
>> >
>> >I am not sure how we could do this. Exposing "maint btrace info"
>> >and parsing that would be one way, not sure if we want to go down
>> >that path.
>>
>> We could warn at decode-time when applying the ptwrite filter.
>> We should have different warning texts for GDB (via libipt) not
>> supporting ptwrite and the system (kernel or h/w) not supporting it.
>>
>> Not as good as an error when installing the ptwrite filter but better
>> than wondering why it isn't working as expected.
>
>Mhm, I don't see this either. We can't warn when we actually would
>apply the filter, as we never would get a ptwrite event.

I was referring to the apply_ext_lang_ptwrite_filter() call in ftrace_add_pt().

> As we don't
>enable ptwrite in Linux if libipt doesn't support it.  And if libipt doesn't
>support it, we wouldn't get to that place in GDB in the first place,
>as there is an #ifdef protecting it.
>
>I looked at doing it when installing the extension language callback
>for ptwrite in btrace.c, e.g. something similar to this:
>
>  /* Register the ptwrite filter.  */
>  if (btinfo->target->conf.pt.ptwrite)
>	apply_ext_lang_ptwrite_filter (btinfo);
>  else
>    warning (_("Can't decode ptwrite events."));
>
>This we do regardless of libipt. But then we would get a warning
>regardless of the user trying to use ptwrite or not (with old libipt
>versions). Plus this doesn't compile, as struct btrace_target_info
>is forward declared, and we probably can't change that as btrace.c
>should be target independent.

We'd want the check inside gdbpy_load_ptwrite_filter(), which gets
called by apply_ext_lang_ptwrite_filter() to install the btrace callback.

This is GDB code so we should be able to check the libipt version as
well ask kernel support.

Regards,
Markus.
Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

RE: [PATCH v10 05/10] python: Introduce gdb.RecordAuxiliary class.

[Metzger, Markus T]

Hello Felix,

>> >> >@@ -455,10 +511,10 @@ btpy_list_item (PyObject *self, Py_ssize_t index)
>> >> >
>> >> >   number = obj->first + (obj->step * index);
>> >> >
>> >> >-  if (obj->element_type == &recpy_insn_type)
>> >> >-    return recpy_insn_new (obj->thread, RECORD_METHOD_BTRACE,
>> number);
>> >> >-  else
>> >> >+  if (obj->element_type == &recpy_func_type)
>> >> >     return recpy_func_new (obj->thread, RECORD_METHOD_BTRACE,
>> number);
>> >> >+  else
>> >> >+    return btpy_item_new (obj->thread, number);
>> >> > }
>> >>
>> >> Why do we need to change the order?
>> >
>> >Because we no longer call recpy_insn_new only for recpy_insn_type but also for
>> >recpy_aux_type.
>>
>> I think it would be clearer if we checked each type separately and errored
>> out by default.  Like a switch.
>
>I can put something like this:
>
>  if (obj->element_type == &recpy_func_type)
>    return recpy_func_new (obj->thread, RECORD_METHOD_BTRACE, number);
>  else if (obj->element_type == &recpy_insn_type
>	   || obj->element_type == &recpy_aux_type)
>    return btpy_item_new (obj->thread, number);
>  else
>    return PyErr_Format (gdbpy_gdb_error, _("Not a valid BtraceList object."));
>
>I don't think we can reach the error case right now though.

We will reach the error case when we add a new element type and forget to
update this function.

LGTM.

Maybe it makes sense to split btpy_item_new() again so we do not accidentally
create an insn object with a recpy_aux_type or vice versa.

How about aux objects in the function call history?  This is supported on CLI if
I read patch 3 correctly.

Regards,
Markus.
Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

RE: [PATCH v10 05/10] python: Introduce gdb.RecordAuxiliary class.

[Willgerodt, Felix]

> -----Original Message-----
> From: Metzger, Markus T <markus.t.metzger@intel.com>
> Sent: Mittwoch, 9. August 2023 12:01
> To: Willgerodt, Felix <felix.willgerodt@intel.com>
> Cc: gdb-patches@sourceware.org; simark@simark.ca
> Subject: RE: [PATCH v10 05/10] python: Introduce gdb.RecordAuxiliary class.
> 
> Hello Felix,
> 
> >> >> >@@ -455,10 +511,10 @@ btpy_list_item (PyObject *self, Py_ssize_t
> index)
> >> >> >
> >> >> >   number = obj->first + (obj->step * index);
> >> >> >
> >> >> >-  if (obj->element_type == &recpy_insn_type)
> >> >> >-    return recpy_insn_new (obj->thread, RECORD_METHOD_BTRACE,
> >> number);
> >> >> >-  else
> >> >> >+  if (obj->element_type == &recpy_func_type)
> >> >> >     return recpy_func_new (obj->thread, RECORD_METHOD_BTRACE,
> >> number);
> >> >> >+  else
> >> >> >+    return btpy_item_new (obj->thread, number);
> >> >> > }
> >> >>
> >> >> Why do we need to change the order?
> >> >
> >> >Because we no longer call recpy_insn_new only for recpy_insn_type but also
> for
> >> >recpy_aux_type.
> >>
> >> I think it would be clearer if we checked each type separately and errored
> >> out by default.  Like a switch.
> >
> >I can put something like this:
> >
> >  if (obj->element_type == &recpy_func_type)
> >    return recpy_func_new (obj->thread, RECORD_METHOD_BTRACE, number);
> >  else if (obj->element_type == &recpy_insn_type
> >	   || obj->element_type == &recpy_aux_type)
> >    return btpy_item_new (obj->thread, number);
> >  else
> >    return PyErr_Format (gdbpy_gdb_error, _("Not a valid BtraceList object."));
> >
> >I don't think we can reach the error case right now though.
> 
> We will reach the error case when we add a new element type and forget to
> update this function.
> 
> LGTM.
> 
> Maybe it makes sense to split btpy_item_new() again so we do not accidentally
> create an insn object with a recpy_aux_type or vice versa.
> 
> How about aux objects in the function call history?  This is supported on CLI if
> I read patch 3 correctly.

Yes, it is showing in CLI. In Python it is a bit more hidden, but also accessible.
The function call history is a list of RecoredFunctionSegment objects. No aux
objects there. But, the RecordFunctionSegment objects all have the instructions
listed as a member:

>>> r = gdb.current_recording()
>>> h = r.function_call_history
>>> h[1]
<gdb.RecordFunctionSegment object at 0x7f76b4587210>
>>> h[1].instructions
<gdb.BtraceObjectList object at 0x7f76ac0abb30>
>>> h[1].instructions[7]
<gdb.RecordInstruction object at 0x7f769c257a50>
>>> h[1].instructions[8]
<gdb.RecordAuxiliary object at 0x7f76b455c8d0>

So a user can still access all the same information. In GDB code, we basically do
the same, just that in the CLI variant of record function-call-history GDB also
searches the insn list for aux objects, and prints them. In Python the user has to
do that himself right now.

I don't think putting aux objects also in the function_call_history would be a
good idea. That would duplicate things.

Anyway, I will change it as we agreed on above.

Felix
Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

RE: [PATCH v10 08/10] btrace, linux: Enable ptwrite packets.

[Willgerodt, Felix]

> -----Original Message-----
> From: Metzger, Markus T <markus.t.metzger@intel.com>
> Sent: Mittwoch, 9. August 2023 11:48
> To: Willgerodt, Felix <felix.willgerodt@intel.com>
> Cc: gdb-patches@sourceware.org; simark@simark.ca
> Subject: RE: [PATCH v10 08/10] btrace, linux: Enable ptwrite packets.
> 
> Hello Felix,
> 
> >> >> >+#if (LIBIPT_VERSION >= 0x200)
> >> >> >+  record_btrace_conf.pt.ptwrite = true;
> >> >> >+#else
> >> >> >+  record_btrace_conf.pt.ptwrite = false;
> >> >> >+#endif
> >> >>
> >> >> Is there a way to get an error when attempting to install a custom
> >> >> ptwrite filter when either GDB (via libipt) or the kernel does not
> >> >> support PTWRITE?
> >> >
> >> >Good point. Unfortunately I don't see one with the current design.
> >> >Currently we just cache the filter functions in python when one is
> >> >registered. The configuration isn't exposed to the python layer in
> >> >any way.
> >> >
> >> >I am not sure how we could do this. Exposing "maint btrace info"
> >> >and parsing that would be one way, not sure if we want to go down
> >> >that path.
> >>
> >> We could warn at decode-time when applying the ptwrite filter.
> >> We should have different warning texts for GDB (via libipt) not
> >> supporting ptwrite and the system (kernel or h/w) not supporting it.
> >>
> >> Not as good as an error when installing the ptwrite filter but better
> >> than wondering why it isn't working as expected.
> >
> >Mhm, I don't see this either. We can't warn when we actually would
> >apply the filter, as we never would get a ptwrite event.
> 
> I was referring to the apply_ext_lang_ptwrite_filter() call in ftrace_add_pt().
> 
> > As we don't
> >enable ptwrite in Linux if libipt doesn't support it.  And if libipt doesn't
> >support it, we wouldn't get to that place in GDB in the first place,
> >as there is an #ifdef protecting it.
> >
> >I looked at doing it when installing the extension language callback
> >for ptwrite in btrace.c, e.g. something similar to this:
> >
> >  /* Register the ptwrite filter.  */
> >  if (btinfo->target->conf.pt.ptwrite)
> >	apply_ext_lang_ptwrite_filter (btinfo);
> >  else
> >    warning (_("Can't decode ptwrite events."));
> >
> >This we do regardless of libipt. But then we would get a warning
> >regardless of the user trying to use ptwrite or not (with old libipt
> >versions). Plus this doesn't compile, as struct btrace_target_info
> >is forward declared, and we probably can't change that as btrace.c
> >should be target independent.
> 
> We'd want the check inside gdbpy_load_ptwrite_filter(), which gets
> called by apply_ext_lang_ptwrite_filter() to install the btrace callback.

If I add a similar warning to what I posted above for btrace.c, to
python/py-record-btrace.c:gdbpy_load_ptwrite_filter(), I still can't
compile. I get the following error:

py-record-btrace.c:906:22: error: invalid use of incomplete type ?struct btrace_target_info?
  906 |   if (!btinfo->target->conf.pt.ptwrite)

The solution would be to include nat/linux-btrace.h to the file, or to move
that struct to some other common header, e.g. btrace-common.h.
I don't think either is possible, it is adding linux specific things to common files.
Or is there any other solution that I missed?

Another point is, even if I would put it there, gdbpy_load_ptwrite_filter()
is called regardless of the user having installed a python filter.
But I think we could additionally check that get_ptwrite_filter() didn't return
Py_None to avoid that issue.

Felix

Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de <http://www.intel.de>
Managing Directors: Christin Eisenschmid, Sharon Heck, Tiffany Doon Silva  
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928

RE: [PATCH v10 08/10] btrace, linux: Enable ptwrite packets.

[Metzger, Markus T]

Hello Felix,

>> >I looked at doing it when installing the extension language callback
>> >for ptwrite in btrace.c, e.g. something similar to this:
>> >
>> >  /* Register the ptwrite filter.  */
>> >  if (btinfo->target->conf.pt.ptwrite)
>> >	apply_ext_lang_ptwrite_filter (btinfo);
>> >  else
>> >    warning (_("Can't decode ptwrite events."));
>> >
>> >This we do regardless of libipt. But then we would get a warning
>> >regardless of the user trying to use ptwrite or not (with old libipt
>> >versions). Plus this doesn't compile, as struct btrace_target_info
>> >is forward declared, and we probably can't change that as btrace.c
>> >should be target independent.
>>
>> We'd want the check inside gdbpy_load_ptwrite_filter(), which gets
>> called by apply_ext_lang_ptwrite_filter() to install the btrace callback.
>
>If I add a similar warning to what I posted above for btrace.c, to
>python/py-record-btrace.c:gdbpy_load_ptwrite_filter(), I still can't
>compile. I get the following error:
>
>py-record-btrace.c:906:22: error: invalid use of incomplete type ?struct
>btrace_target_info?
>  906 |   if (!btinfo->target->conf.pt.ptwrite)
>
>The solution would be to include nat/linux-btrace.h to the file, or to move
>that struct to some other common header, e.g. btrace-common.h.
>I don't think either is possible, it is adding linux specific things to common files.
>Or is there any other solution that I missed?
>
>Another point is, even if I would put it there, gdbpy_load_ptwrite_filter()
>is called regardless of the user having installed a python filter.
>But I think we could additionally check that get_ptwrite_filter() didn't return
>Py_None to avoid that issue.

Yes, that's what I meant.  Warn if a ptwrite filter is installed but ptwrite is not
supported.

We cannot use btrace_target_info directly, so we'd need to add another function
to check whether ptwrite is supported/enabled on the target.

regards,
markus.
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