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| author | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2009-06-02 17:08:15 +0400 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-06-02 23:45:29 +0400 |
| commit | 8e5799b1ad2a0567fdfaaf0e91b40efee010f2c1 (patch) | |
| tree | bd3f45c348f48411a4496229572643211cbd59b8 /kernel/perf_counter.c | |
| parent | 53e111a730ea8b002d57dd226098c12789993329 (diff) | |
| download | linux-8e5799b1ad2a0567fdfaaf0e91b40efee010f2c1.tar.xz | |
perf_counter: Add unique counter id
Stephan raised the issue that we currently cannot distinguish between
similar counters within a group (PERF_RECORD_GROUP uses the config
value as identifier).
Therefore, generate a new ID for each counter using a global u64
sequence counter.
Reported-by: Stephane Eranian <eranian@googlemail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/perf_counter.c')
| -rw-r--r-- | kernel/perf_counter.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index caa012cfe49a..978ecfcc7aaf 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -1510,6 +1510,8 @@ perf_read_hw(struct perf_counter *counter, char __user *buf, size_t count) if (counter->hw_event.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) values[n++] = counter->total_time_running + atomic64_read(&counter->child_total_time_running); + if (counter->hw_event.read_format & PERF_FORMAT_ID) + values[n++] = counter->id; mutex_unlock(&counter->child_mutex); if (count < n * sizeof(u64)) @@ -2303,7 +2305,7 @@ static void perf_counter_output(struct perf_counter *counter, u32 pid, tid; } tid_entry; struct { - u64 event; + u64 id; u64 counter; } group_entry; struct perf_callchain_entry *callchain = NULL; @@ -2416,7 +2418,7 @@ static void perf_counter_output(struct perf_counter *counter, if (sub != counter) sub->pmu->read(sub); - group_entry.event = sub->hw_event.config; + group_entry.id = sub->id; group_entry.counter = atomic64_read(&sub->count); perf_output_put(&handle, group_entry); @@ -3375,6 +3377,8 @@ done: return counter; } +static atomic64_t perf_counter_id; + /** * sys_perf_counter_open - open a performance counter, associate it to a task/cpu * @@ -3470,6 +3474,7 @@ SYSCALL_DEFINE5(perf_counter_open, mutex_unlock(¤t->perf_counter_mutex); counter->ns = get_pid_ns(current->nsproxy->pid_ns); + counter->id = atomic64_inc_return(&perf_counter_id); fput_light(counter_file, fput_needed2); |