perf trace: Add interface to access perf data from Perl handlers

The Perl scripting support for perf trace allows most of a trace
event's data to be accessed directly as handler arguments, but
not all of it e.g. the less common fields aren't passed in.  To
give scripts access to the other fields and/or any other data or
metadata in the main perf executable that might be useful, a way
to access the C data in perf from Perl is needed; this patch
uses the Perl XS facility to do it for the common_xxx event
fields not passed to handler functions.

Context.pm exports three functions to Perl scripts that access
fields for the current event by calling back into perf:
common_pc(), common_flags() and common_lock_depth().  Support
for common_flags() field values was added to Core.pm and a
script used to sanity check these and other basic scripting
features, check-perf-trace.pl, was also added.

Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Cc: fweisbec@gmail.com
Cc: rostedt@goodmis.org
Cc: anton@samba.org
Cc: hch@infradead.org
LKML-Reference: <1259133352-23685-6-git-send-email-tzanussi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 9 insertions, 0 deletions

diff --git a/tools/perf/util/trace-event-perl.h b/tools/perf/util/trace-event-perl.h
index 6c94fa93013d..666a864f5dda 100644
--- a/tools/perf/util/trace-event-perl.h
+++ b/tools/perf/util/trace-event-perl.h
@@ -29,6 +29,11 @@ typedef int INTERP;
 #define perl_run(a)		(0)
 #define perl_destruct(a)	(0)
 #define perl_free(a)		(0)
+#define pTHX			void
+#define CV			void
+#define dXSUB_SYS
+#define pTHX_
+static inline void newXS(const char *a, void *b, const char *c) {}
 #else
 #include <EXTERN.h>
 #include <perl.h>
@@ -39,4 +44,8 @@ struct scripting_context {
 	void *event_data;
 };
 
+int get_common_pc(struct scripting_context *context);
+int get_common_flags(struct scripting_context *context);
+int get_common_lock_depth(struct scripting_context *context);
+
 #endif /* __PERF_TRACE_EVENT_PERL_H */