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[PATCH 01/10] perf probe: Cut off the gcc optimization postfixes from function name

From Arnaldo Carvalho de Melo <acme@kernel.org>
Newsgroups linux.kernel
Subject [PATCH 01/10] perf probe: Cut off the gcc optimization postfixes from function name
Date 2015-06-16 20:30 +0200
Message-ID <pC3Mv-22f-31@gated-at.bofh.it> (permalink)
References <pC3Mu-22f-3@gated-at.bofh.it>
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From: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>

Cut off the postfixes which gcc added for optimized routines from the
event name automatically generated from symbol name, since *probe-events
doesn't accept it.  Those symbols will be used if we don't use debuginfo
to find target functions.

E.g. without this fix;
  -----
  # perf probe -va alloc_buf.isra.23
  probe-definition(0): alloc_buf.isra.23
  symbol:alloc_buf.isra.23 file:(null) line:0 offset:0 return:0 lazy:(null)
  [...]
  Opening /sys/kernel/debug/tracing/kprobe_events write=1
  Added new event:
  Writing event: p:probe/alloc_buf.isra.23 _text+4869328
  Failed to write event: Invalid argument
    Error: Failed to add events. Reason: Invalid argument (Code: -22)
  -----
With this fix;
  -----
  perf probe -va alloc_buf.isra.23
  probe-definition(0): alloc_buf.isra.23
  symbol:alloc_buf.isra.23 file:(null) line:0 offset:0 return:0 lazy:(null)
  [...]
  Opening /sys/kernel/debug/tracing/kprobe_events write=1
  Added new event:
  Writing event: p:probe/alloc_buf _text+4869328
    probe:alloc_buf      (on alloc_buf.isra.23)

  You can now use it in all perf tools, such as:

  	perf record -e probe:alloc_buf -aR sleep 1

  -----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150612050820.20548.41625.stgit@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/probe-event.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index d4cf50b91839..daa24a249e05 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -2316,6 +2316,7 @@ static int get_new_event_name(char *buf, size_t len, const char *base,
 			      struct strlist *namelist, bool allow_suffix)
 {
 	int i, ret;
+	char *p;
 
 	if (*base == '.')
 		base++;
@@ -2326,6 +2327,10 @@ static int get_new_event_name(char *buf, size_t len, const char *base,
 		pr_debug("snprintf() failed: %d\n", ret);
 		return ret;
 	}
+	/* Cut off the postfixes (e.g. .const, .isra)*/
+	p = strchr(buf, '.');
+	if (p && p != buf)
+		*p = '\0';
 	if (!strlist__has_entry(namelist, buf))
 		return 0;
 
-- 
2.1.0

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Thread

[GIT PULL 00/10] perf/core improvements and fixes Arnaldo Carvalho de Melo <acme@kernel.org> - 2015-06-16 20:30 +0200
  [PATCH 02/10] perf tools: Replace map->referenced & maps->removed_maps with map->refcnt Arnaldo Carvalho de Melo <acme@kernel.org> - 2015-06-16 20:30 +0200
  [PATCH 05/10] perf tools: Introduce xyarray__reset function Arnaldo Carvalho de Melo <acme@kernel.org> - 2015-06-16 20:30 +0200
  [PATCH 08/10] perf stat: Introduce perf_counts__(new|delete|reset) functions Arnaldo Carvalho de Melo <acme@kernel.org> - 2015-06-16 20:30 +0200
  [PATCH 10/10] perf probe: Fix to return error if no probe is added Arnaldo Carvalho de Melo <acme@kernel.org> - 2015-06-16 20:30 +0200
  [PATCH 09/10] perf unwind: Fix a compile error Arnaldo Carvalho de Melo <acme@kernel.org> - 2015-06-16 20:30 +0200
  [PATCH 01/10] perf probe: Cut off the gcc optimization postfixes from function name Arnaldo Carvalho de Melo <acme@kernel.org> - 2015-06-16 20:30 +0200
  [PATCH 03/10] tools lib traceevent: Fix python/perf.so compiling error Arnaldo Carvalho de Melo <acme@kernel.org> - 2015-06-16 20:30 +0200
  [PATCH 07/10] perf tools: Move perf_evsel__(alloc|free|reset)_counts into stat object Arnaldo Carvalho de Melo <acme@kernel.org> - 2015-06-16 20:30 +0200

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