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author | 2016-09-24 00:35:07 +0900 | |
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committer | 2016-09-29 11:17:07 -0300 | |
commit | 0ad45b33c58dca60dec7e1fb44766753bc4a7a38 (patch) | |
tree | 94789d49441a8c4cfbcc9d5c42fdf286f4f47220 /tools/perf | |
parent | perf probe: Ignore the error of finding inline instance (diff) | |
download | linux-0ad45b33c58dca60dec7e1fb44766753bc4a7a38.tar.gz linux-0ad45b33c58dca60dec7e1fb44766753bc4a7a38.tar.bz2 linux-0ad45b33c58dca60dec7e1fb44766753bc4a7a38.zip |
perf probe: Skip if the function address is 0
Skip probes if the entry address of the target function is 0. This can
happen when we're handling C++ debuginfo files.
E.g. without this fix, below case still fail.
----
$ ./perf probe -x /usr/lib64/libstdc++.so.6 -vD is_open
probe-definition(0): is_open
symbol:is_open file:(null) line:0 offset:0 return:0 lazy:(null)
0 arguments
symbol:catch file:(null) line:0 offset:0 return:0 lazy:(null)
symbol:throw file:(null) line:0 offset:0 return:0 lazy:(null)
symbol:rethrow file:(null) line:0 offset:0 return:0 lazy:(null)
Open Debuginfo file: /usr/lib/debug/usr/lib64/libstdc++.so.6.0.22.debug
Try to find probe point from debuginfo.
Matched function: is_open [295df]
found inline addr: 0x8ca80
Probe point found: is_open+0
found inline addr: 0x8ca70
Probe point found: is_open+0
found inline addr: 0x8ca60
Probe point found: is_open+0
Matched function: is_open [6527f]
Matched function: is_open [9fe8a]
Probe point found: is_open+0
Matched function: is_open [19710b]
found inline addr: 0xecca9
Probe point found: stdio_filebuf+57
found inline addr: 0x0
Probe point found: swap+0
Matched function: is_open [19fc9d]
Probe point found: is_open+0
Found 7 probe_trace_events.
p:probe_libstdc++/is_open /usr/lib64/libstdc++.so.6.0.22:0x8ca80
p:probe_libstdc++/is_open_1 /usr/lib64/libstdc++.so.6.0.22:0x8ca70
p:probe_libstdc++/is_open_2 /usr/lib64/libstdc++.so.6.0.22:0x8ca60
p:probe_libstdc++/is_open_3 /usr/lib64/libstdc++.so.6.0.22:0xb0ad0
p:probe_libstdc++/is_open_4 /usr/lib64/libstdc++.so.6.0.22:0xecca9
Failed to synthesize probe trace event.
Error: Failed to add events. Reason: Invalid argument (Code: -22)
----
This is because some instances have entry_pc == 0 (see 19710b and
19fc9d). With this fix, those are skipped.
----
$ ./perf probe -x /usr/lib64/libstdc++.so.6 -D is_open
p:probe_libstdc++/is_open /usr/lib64/libstdc++.so.6.0.22:0x8ca80
p:probe_libstdc++/is_open_1 /usr/lib64/libstdc++.so.6.0.22:0x8ca70
p:probe_libstdc++/is_open_2 /usr/lib64/libstdc++.so.6.0.22:0x8ca60
p:probe_libstdc++/is_open_3 /usr/lib64/libstdc++.so.6.0.22:0xb0ad0
p:probe_libstdc++/is_open_4 /usr/lib64/libstdc++.so.6.0.22:0xecca9
----
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/147464490707.29804.14277897643725143867.stgit@devbox
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf')
-rw-r--r-- | tools/perf/util/probe-finder.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c index 5fe8325e81f2..df4debe564da 100644 --- a/tools/perf/util/probe-finder.c +++ b/tools/perf/util/probe-finder.c @@ -955,6 +955,11 @@ static int probe_point_inline_cb(Dwarf_Die *in_die, void *data) dwarf_diename(in_die)); return -ENOENT; } + if (addr == 0) { + pr_debug("%s has no valid entry address. skipped.\n", + dwarf_diename(in_die)); + return -ENOENT; + } pf->addr = addr; pf->addr += pp->offset; pr_debug("found inline addr: 0x%jx\n", @@ -998,8 +1003,13 @@ static int probe_point_search_cb(Dwarf_Die *sp_die, void *data) } else if (die_is_func_instance(sp_die)) { /* Instances always have the entry address */ dwarf_entrypc(sp_die, &pf->addr); + /* But in some case the entry address is 0 */ + if (pf->addr == 0) { + pr_debug("%s has no entry PC. Skipped\n", + dwarf_diename(sp_die)); + param->retval = 0; /* Real function */ - if (pp->lazy_line) + } else if (pp->lazy_line) param->retval = find_probe_point_lazy(sp_die, pf); else { skip_prologue(sp_die, pf); |