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| author | Alexis Berlemont <alexis.berlemont@gmail.com> | 2016-10-10 07:43:28 +0200 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2016-10-24 11:07:43 -0300 |
| commit | e36b7821a985325dd7074de96deface5c9c6d700 (patch) | |
| tree | 59dc7200af2f06380cd7bcba99fd9a4d474a4bea /tools/perf/builtin-trace.c | |
| parent | 21e8c81095cdbbde9d2aba8fffc51cb9b5e0eeaa (diff) | |
| download | linux-e36b7821a985325dd7074de96deface5c9c6d700.tar.gz linux-e36b7821a985325dd7074de96deface5c9c6d700.tar.bz2 linux-e36b7821a985325dd7074de96deface5c9c6d700.zip | |
perf trace: Implement --delay
In the perf wiki todo-list[1], there is an entry regarding initial-delay
and 'perf trace'; the following small patch tries to fulfill this point.
It has been generated against the branch tip/perf/core.
It has only been implemented in the "trace__run" case.
Ex.:
$ sudo strace -- ./perf trace --delay 5 sleep 1 2>&1
...
fcntl(7, F_SETFL, O_RDONLY|O_NONBLOCK) = 0
ioctl(7, PERF_EVENT_IOC_ID, 0x7ffc8fd35718) = 0
ioctl(11, PERF_EVENT_IOC_SET_OUTPUT, 0x7) = 0
fcntl(11, F_SETFL, O_RDONLY|O_NONBLOCK) = 0
ioctl(11, PERF_EVENT_IOC_ID, 0x7ffc8fd35718) = 0
write(6, "\0", 1) = 1
close(6) = 0
nanosleep({0, 5000000}, NULL) = 0 # DELAY OF 5 MS BEFORE ENABLING THE EVENTS
ioctl(3, PERF_EVENT_IOC_ENABLE, 0) = 0
ioctl(4, PERF_EVENT_IOC_ENABLE, 0) = 0
ioctl(5, PERF_EVENT_IOC_ENABLE, 0) = 0
ioctl(7, PERF_EVENT_IOC_ENABLE, 0) = 0
...
[1]: https://perf.wiki.kernel.org/index.php/Todo
Signed-off-by: Alexis Berlemont <alexis.berlemont@gmail.com>
Suggested-and-Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20161010054328.4028-2-alexis.berlemont@gmail.com
[ Add entry to the manpage, cut'n'pasted from stat's and record's ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/builtin-trace.c')
| -rw-r--r-- | tools/perf/builtin-trace.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index c298bd3e1d90..0bae454e8efa 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -2310,12 +2310,17 @@ static int trace__run(struct trace *trace, int argc, const char **argv) if (err < 0) goto out_error_mmap; - if (!target__none(&trace->opts.target)) + if (!target__none(&trace->opts.target) && !trace->opts.initial_delay) perf_evlist__enable(evlist); if (forks) perf_evlist__start_workload(evlist); + if (trace->opts.initial_delay) { + usleep(trace->opts.initial_delay * 1000); + perf_evlist__enable(evlist); + } + trace->multiple_threads = thread_map__pid(evlist->threads, 0) == -1 || evlist->threads->nr > 1 || perf_evlist__first(evlist)->attr.inherit; @@ -2816,6 +2821,9 @@ int cmd_trace(int argc, const char **argv, const char *prefix __maybe_unused) "Default: kernel.perf_event_max_stack or " __stringify(PERF_MAX_STACK_DEPTH)), OPT_UINTEGER(0, "proc-map-timeout", &trace.opts.proc_map_timeout, "per thread proc mmap processing timeout in ms"), + OPT_UINTEGER('D', "delay", &trace.opts.initial_delay, + "ms to wait before starting measurement after program " + "start"), OPT_END() }; bool __maybe_unused max_stack_user_set = true; |