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| author | Adrian Hunter <adrian.hunter@intel.com> | 2018-02-28 09:39:04 +0100 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2018-03-06 15:31:14 +0100 |
| commit | de19e5c3c51fdb1ff20d0f61d099db902ff7494b (patch) | |
| tree | 2d87d58f22c122d35c20069ff7b6cbae097bc6ee | |
| parent | perf auxtrace: Prevent decoding when --no-itrace (diff) | |
| download | linux-de19e5c3c51fdb1ff20d0f61d099db902ff7494b.tar.xz linux-de19e5c3c51fdb1ff20d0f61d099db902ff7494b.zip | |
perf tools: Fix trigger class trigger_on()
trigger_on() means that the trigger is available but not ready, however
trigger_on() was making it ready. That can segfault if the signal comes
before trigger_ready(). e.g. (USR2 signal delivery not shown)
$ perf record -e intel_pt//u -S sleep 1
perf: Segmentation fault
Obtained 16 stack frames.
/home/ahunter/bin/perf(sighandler_dump_stack+0x40) [0x4ec550]
/lib/x86_64-linux-gnu/libc.so.6(+0x36caf) [0x7fa76411acaf]
/home/ahunter/bin/perf(perf_evsel__disable+0x26) [0x4b9dd6]
/home/ahunter/bin/perf() [0x43a45b]
/lib/x86_64-linux-gnu/libc.so.6(+0x36caf) [0x7fa76411acaf]
/lib/x86_64-linux-gnu/libc.so.6(__xstat64+0x15) [0x7fa7641d2cc5]
/home/ahunter/bin/perf() [0x4ec6c9]
/home/ahunter/bin/perf() [0x4ec73b]
/home/ahunter/bin/perf() [0x4ec73b]
/home/ahunter/bin/perf() [0x4ec73b]
/home/ahunter/bin/perf() [0x4eca15]
/home/ahunter/bin/perf(machine__create_kernel_maps+0x257) [0x4f0b77]
/home/ahunter/bin/perf(perf_session__new+0xc0) [0x4f86f0]
/home/ahunter/bin/perf(cmd_record+0x722) [0x43c132]
/home/ahunter/bin/perf() [0x4a11ae]
/home/ahunter/bin/perf(main+0x5d4) [0x427fb4]
Note, for testing purposes, this is hard to hit unless you add some sleep()
in builtin-record.c before record__open().
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: stable@vger.kernel.org
Fixes: 3dcc4436fa6f ("perf tools: Introduce trigger class")
Link: http://lkml.kernel.org/r/1519807144-30694-1-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
| -rw-r--r-- | tools/perf/util/trigger.h | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/tools/perf/util/trigger.h b/tools/perf/util/trigger.h index 370138e7e35c..88223bc7c82b 100644 --- a/tools/perf/util/trigger.h +++ b/tools/perf/util/trigger.h @@ -12,7 +12,7 @@ * States and transits: * * - * OFF--(on)--> READY --(hit)--> HIT + * OFF--> ON --> READY --(hit)--> HIT * ^ | * | (ready) * | | @@ -27,8 +27,9 @@ struct trigger { volatile enum { TRIGGER_ERROR = -2, TRIGGER_OFF = -1, - TRIGGER_READY = 0, - TRIGGER_HIT = 1, + TRIGGER_ON = 0, + TRIGGER_READY = 1, + TRIGGER_HIT = 2, } state; const char *name; }; @@ -50,7 +51,7 @@ static inline bool trigger_is_error(struct trigger *t) static inline void trigger_on(struct trigger *t) { TRIGGER_WARN_ONCE(t, TRIGGER_OFF); - t->state = TRIGGER_READY; + t->state = TRIGGER_ON; } static inline void trigger_ready(struct trigger *t) |