From: Felix Willgerodt <felix.willgerodt@intel.com>
To: gdb-patches@sourceware.org, markus.t.metzger@intel.com
Subject: [PATCH v7 08/10] btrace, linux: Enable ptwrite packets.
Date: Fri, 21 Oct 2022 13:59:45 +0200 [thread overview]
Message-ID: <20221021115947.359223-9-felix.willgerodt@intel.com> (raw)
In-Reply-To: <20221021115947.359223-1-felix.willgerodt@intel.com>
Enable ptwrite in the PT config, if it is supported by the kernel.
---
gdb/nat/linux-btrace.c | 29 +++++++++++++++++++++++++++++
gdb/record-btrace.c | 5 +++++
2 files changed, 34 insertions(+)
diff --git a/gdb/nat/linux-btrace.c b/gdb/nat/linux-btrace.c
index 4911630ba5c..701ea948610 100644
--- a/gdb/nat/linux-btrace.c
+++ b/gdb/nat/linux-btrace.c
@@ -415,6 +415,29 @@ cpu_supports_bts (void)
}
}
+/* Check whether the linux target supports Intel Processor Trace PTWRITE. */
+
+static bool
+linux_supports_ptwrite ()
+{
+ 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;
+ }
+
+ return status == 1;
+}
+
/* The perf_event_open syscall failed. Try to print a helpful error
message. */
@@ -624,6 +647,12 @@ linux_enable_pt (ptid_t ptid, const struct btrace_config_pt *conf)
pt->attr.exclude_hv = 1;
pt->attr.exclude_idle = 1;
+ if (conf->ptwrite && linux_supports_ptwrite ())
+ {
+ pt->attr.config |= 0x1000;
+ 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 0767dd12fee..203d994a306 100644
--- a/gdb/record-btrace.c
+++ b/gdb/record-btrace.c
@@ -3286,4 +3286,9 @@ 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
}
--
2.34.3
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
WARNING: multiple messages have this Message-ID
From: Felix Willgerodt <felix.willgerodt@intel.com>
To: gdb-patches@sourceware.org, markus.t.metzger@intel.com
Cc: Felix Willgerodt <felix.willgerodt@intel.com>
Subject: [PATCH v7 08/10] btrace, linux: Enable ptwrite packets.
Date: Fri, 21 Oct 2022 13:59:45 +0200 [thread overview]
Message-ID: <20221021115947.359223-9-felix.willgerodt@intel.com> (raw)
Message-ID: <20221021115945.aVO_ukE-sARPVjjda4NYRcD32GOFzDC5I2q7Q-k_1NQ@z> (raw)
In-Reply-To: <20221021115947.359223-1-felix.willgerodt@intel.com>
Enable ptwrite in the PT config, if it is supported by the kernel.
---
gdb/nat/linux-btrace.c | 29 +++++++++++++++++++++++++++++
gdb/record-btrace.c | 5 +++++
2 files changed, 34 insertions(+)
diff --git a/gdb/nat/linux-btrace.c b/gdb/nat/linux-btrace.c
index 4911630ba5c..701ea948610 100644
--- a/gdb/nat/linux-btrace.c
+++ b/gdb/nat/linux-btrace.c
@@ -415,6 +415,29 @@ cpu_supports_bts (void)
}
}
+/* Check whether the linux target supports Intel Processor Trace PTWRITE. */
+
+static bool
+linux_supports_ptwrite ()
+{
+ 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;
+ }
+
+ return status == 1;
+}
+
/* The perf_event_open syscall failed. Try to print a helpful error
message. */
@@ -624,6 +647,12 @@ linux_enable_pt (ptid_t ptid, const struct btrace_config_pt *conf)
pt->attr.exclude_hv = 1;
pt->attr.exclude_idle = 1;
+ if (conf->ptwrite && linux_supports_ptwrite ())
+ {
+ pt->attr.config |= 0x1000;
+ 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 0767dd12fee..203d994a306 100644
--- a/gdb/record-btrace.c
+++ b/gdb/record-btrace.c
@@ -3286,4 +3286,9 @@ 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
}
--
2.34.3
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
next prev parent reply other threads:[~2022-10-21 12:02 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-21 11:59 [PATCH v7 00/10] Extensions for PTWRITE Felix Willgerodt
2022-10-21 11:59 ` Felix Willgerodt
2022-10-21 11:59 ` [PATCH v7 01/10] btrace: Introduce auxiliary instructions Felix Willgerodt
2022-10-21 11:59 ` Felix Willgerodt
2022-10-21 13:19 ` Eli Zaretskii
2022-10-21 11:59 ` [PATCH v7 02/10] btrace: Enable auxiliary instructions in record instruction-history Felix Willgerodt
2022-10-21 11:59 ` [PATCH v7 03/10] btrace: Enable auxiliary instructions in record function-call-history Felix Willgerodt
2022-10-21 11:59 ` Felix Willgerodt
2022-10-21 11:59 ` [PATCH v7 04/10] btrace: Handle stepping and goto for auxiliary instructions Felix Willgerodt
2022-10-21 11:59 ` Felix Willgerodt
2022-10-21 11:59 ` [PATCH v7 05/10] python: Introduce gdb.RecordAuxiliary class Felix Willgerodt
2022-10-21 11:59 ` Felix Willgerodt
2022-10-21 11:59 ` [PATCH v7 06/10] python: Add clear() to gdb.Record Felix Willgerodt
2022-10-21 11:59 ` Felix Willgerodt
2022-10-21 11:59 ` [PATCH v7 07/10] btrace, gdbserver: Add ptwrite to btrace_config_pt Felix Willgerodt
2022-10-21 11:59 ` Felix Willgerodt
2022-10-21 11:59 ` Felix Willgerodt [this message]
2022-10-21 11:59 ` [PATCH v7 08/10] btrace, linux: Enable ptwrite packets Felix Willgerodt
2022-10-21 11:59 ` [PATCH v7 09/10] btrace, python: Enable ptwrite filter registration Felix Willgerodt
2022-10-21 11:59 ` Felix Willgerodt
2022-11-09 13:16 ` [PING] [PATCH v7 00/10] Extensions for PTWRITE Willgerodt, Felix
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