Re: systemtap markers and gdb

[Tom Tromey <tromey@redhat.com>]

Tom> I didn't rewrite the docs yet, but here is the new proposal.

Here's my new doc patch.

Tom

diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 7f8c785..a93ddf3 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -3304,6 +3304,7 @@ all breakpoints in that range are operated on.
 * Conditions::                  Break conditions
 * Break Commands::              Breakpoint command lists
 * Save Breakpoints::            How to save breakpoints in a file
+* Static Probe Points::         Listing static probe points
 * Error in Breakpoints::        ``Cannot insert breakpoints''
 * Breakpoint-related Warnings:: ``Breakpoint address adjusted...''
 @end menu
@@ -4517,6 +4518,49 @@ and remove the breakpoint definitions you're not interested in, or
 that can no longer be recreated.
 @end table
 
+@node Static Probe Points
+@subsection Static Probe Points
+
+@cindex SystemTap static probe point
+The @sc{gnu}/Linux tool @code{SystemTap} provides a way for
+applications to embed static probes.  @value{GDBN} can list the
+available probes, and you can put breakpoints at the probe points
+(@pxref{Specify Location}).
+
+You can examine the available @code{SystemTap} static probes using
+@code{info probes}:
+
+@table @code
+@kindex info probes
+@item info probes [@var{provider} [@var{name} [@var{objfile}]]]
+List the available @code{SystemTap} static probes.
+
+If given, @var{provider} is a regular expression used to select which
+providers to list.  If omitted, all providers are listed.
+
+If given, @var{name} is a regular expression used to select which
+probes to list.  If omitted, all probes are listed.
+
+If given, @var{objfile} is a regular expression used to select which
+object files (executable or shared libraries) to examine.  If not
+given, all object files are considered.
+@end table
+
+@vindex $_probe_arg@r{, convenience variable}
+A probe may specify up to ten arguments.  These are available at the
+point at which the probe is defined---that is, when the current PC is
+at the probe's location.  The arguments are available using the
+convenience variables (@pxref{Convenience Vars})
+@code{$_probe_arg0}@dots{}@code{$_probe_arg9}.  Each probe argument is
+an integer of the appropriate size; types are not preserved.  The
+convenience variable @code{$_probe_argc} holds the number of arguments
+at the current probe point.
+
+These variable are always available, but attempts to access them at
+any location other than a probe point will cause @value{GDBN} to give
+an error.
+
+
 @c  @ifclear BARETARGET
 @node Error in Breakpoints
 @subsection ``Cannot insert breakpoints''
@@ -6429,6 +6473,21 @@ specify the function unambiguously, e.g., if there are several
 functions with identical names in different source files.
 @end table
 
+@cindex SystemTap static probe point
+@item probe:@r{[}@var{objfile}:@r{]}@r{[}@var{provider}:@r{]}@var{name}
+The @sc{gnu}/Linux tool @code{SystemTap} provides a way for
+applications to embed static probes.  This form of linespec specifies
+the location of such a static probe.  See
+@uref{http://sourceware.org/systemtap/wiki/AddingUserSpaceProbingToApps}
+for more information on static probes.
+
+If @var{objfile} is given, only probes coming from that shared library
+or executable are considered.  If @var{provider} is given, then only
+probes from that provider are considered.
+
+@xref{Static Probe Points}, for more information on finding and using
+static probes.
+
 @end table
 
 
@@ -8503,6 +8562,10 @@ to match the format in which the data was printed.
 The variable @code{$_exitcode} is automatically set to the exit code when
 the program being debugged terminates.
 
+@item $_probe_argc
+@itemx $_probe_arg0@dots{}$_probe_arg9
+Arguments to a SystemTap static probe.  @xref{Static Probe Points}.
+
 @item $_sdata
 @vindex $_sdata@r{, inspect, convenience variable}
 The variable @code{$_sdata} contains extra collected static tracepoint