From: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
To: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>,
Peter Zijlstra <peterz@infradead.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
David Ahern <dsahern@gmail.com>,
namhyung@kernel.org, Jiri Olsa <jolsa@redhat.com>,
Ingo Molnar <mingo@kernel.org>
Subject: [PATCH perf/core v2 5/5] perf probe: Allow weak symbols to be probed
Date: Fri, 06 Mar 2015 16:31:29 +0900 [thread overview]
Message-ID: <20150306073129.6904.41078.stgit@localhost.localdomain> (raw)
In-Reply-To: <20150306073118.6904.72740.stgit@localhost.localdomain>
From: Namhyung Kim <namhyung@kernel.org>
It currently prevents adding probes in weak symbols. But there're cases
that given name is an only weak symbol so that we cannot add probe.
$ perf probe -x /usr/lib/libc.so.6 -a calloc
Failed to find symbol calloc in /usr/lib/libc-2.21.so
Error: Failed to add events.
$ nm /usr/lib/libc.so.6 | grep calloc
000000000007b1f0 t __calloc
000000000007b1f0 T __libc_calloc
000000000007b1f0 W calloc
This change will result in duplicate probes when strong and weak symbols
co-exist in a binary. But I think it's not a big problem since probes
at the weak symbol will never be hit anyway.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
tools/perf/util/probe-event.c | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index c379ea0..f9c1e53 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -309,10 +309,8 @@ static int find_alternative_probe_point(struct debuginfo *dinfo,
/* Find the address of given function */
map__for_each_symbol_by_name(map, pp->function, sym) {
- if (sym->binding == STB_GLOBAL || sym->binding == STB_LOCAL) {
- address = sym->start;
- break;
- }
+ address = sym->start;
+ break;
}
if (!address) {
ret = -ENOENT;
@@ -2484,8 +2482,7 @@ static int find_probe_functions(struct map *map, char *name)
struct symbol *sym;
map__for_each_symbol_by_name(map, name, sym) {
- if (sym->binding == STB_GLOBAL || sym->binding == STB_LOCAL)
- found++;
+ found++;
}
return found;
@@ -2845,8 +2842,7 @@ static struct strfilter *available_func_filter;
static int filter_available_functions(struct map *map __maybe_unused,
struct symbol *sym)
{
- if ((sym->binding == STB_GLOBAL || sym->binding == STB_LOCAL) &&
- strfilter__compare(available_func_filter, sym->name))
+ if (strfilter__compare(available_func_filter, sym->name))
return 0;
return 1;
}
next prev parent reply other threads:[~2015-03-06 7:33 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-03-06 7:31 [PATCH perf/core v2 0/5] perf-probe: improve glibc support Masami Hiramatsu
2015-03-06 7:31 ` [PATCH perf/core v2 1/5] perf-probe: Fix to handle aliased symbols in glibc Masami Hiramatsu
2015-03-06 17:59 ` Arnaldo Carvalho de Melo
2015-03-06 18:02 ` Arnaldo Carvalho de Melo
2015-03-14 7:02 ` [tip:perf/core] perf probe: " tip-bot for Masami Hiramatsu
2015-03-06 7:31 ` [PATCH perf/core v2 2/5] perf-probe: Fix --line " Masami Hiramatsu
2015-03-14 7:02 ` [tip:perf/core] perf probe: " tip-bot for Masami Hiramatsu
2015-03-06 7:31 ` [PATCH perf/core v2 3/5] Revert "perf probe: Fix to fall back to find probe point in symbols" Masami Hiramatsu
2015-03-14 7:03 ` [tip:perf/core] " tip-bot for Masami Hiramatsu
2015-03-06 7:31 ` [PATCH perf/core v2 4/5] perf symbols: Allow symbol alias when loading map for symbol name Masami Hiramatsu
2015-03-06 18:06 ` Arnaldo Carvalho de Melo
2015-03-06 18:26 ` Arnaldo Carvalho de Melo
2015-03-06 18:32 ` Arnaldo Carvalho de Melo
2015-03-14 7:03 ` [tip:perf/core] " tip-bot for Namhyung Kim
2015-03-06 7:31 ` Masami Hiramatsu [this message]
2015-03-14 7:03 ` [tip:perf/core] perf probe: Allow weak symbols to be probed tip-bot for Namhyung Kim
2015-03-06 18:45 ` [PATCH perf/core v2 0/5] perf-probe: improve glibc support Arnaldo Carvalho de Melo
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