[tip:perfcounters/core] perf trace: Sample the CPU too

tip-bot for Ingo Molnar
2009-09-02T19:32:43Z

Commit-ID: cd6feeeafddbef6abfe4d90fb26e42fd844d34ed
Gitweb: http://git.kernel.org/tip/cd6feeeafddbef6abfe4d90fb26e42fd844d34ed
Author: Ingo Molnar <mingo@elte.hu>
AuthorDate: Wed, 2 Sep 2009 20:20:38 +0200
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Wed, 2 Sep 2009 21:28:50 +0200

perf trace: Sample the CPU too

Sample, record, parse and print the CPU field - it had all zeroes before.

Before (watch the second column, the CPU values):

perf-32685 [000] 0.000000: sched_wakeup_new: task perf:32686 [120] success=1 [011]
perf-32685 [000] 0.000000: sched_migrate_task: task perf:32685 [120] from: 1 to: 11
perf-32685 [000] 0.000000: sched_process_fork: parent perf:32685 child perf:32686
true-32686 [000] 0.000000: sched_wakeup: task migration/11:25 [0] success=1 [011]
true-32686 [000] 0.000000: sched_wakeup: task distccd:12793 [125] success=1 [015]
true-32686 [000] 0.000000: sched_wakeup: task distccd:12793 [125] success=1 [015]
perf-32685 [000] 0.000000: sched_switch: task perf:32685 [120] (S) ==> swapper:0 [140]
true-32686 [000] 0.000000: sched_switch: task perf:32686 [120] (R) ==> migration/11:25 [0]
true-32686 [000] 0.000000: sched_switch: task perf:32686 [120] (R) ==> distccd:12793 [125]
true-32686 [000] 0.000000: sched_switch: task true:32686 [120] (R) ==> distccd:12793 [125]
true-32686 [000] 0.000000: sched_process_exit: task true:32686 [120]
true-32686 [000] 0.000000: sched_stat_wait: task: distccd:12793 wait: 6767985949080 [ns]
true-32686 [000] 0.000000: sched_stat_wait: task: distccd:12793 wait: 6767986139446 [ns]
true-32686 [000] 0.000000: sched_stat_sleep: task: distccd:12793 sleep: 132844 [ns]
true-32686 [000] 0.000000: sched_stat_sleep: task: distccd:12793 sleep: 131724 [ns]

After:

perf-32685 [001] 0.000000: sched_wakeup_new: task perf:32686 [120] success=1 [011]
perf-32685 [001] 0.000000: sched_migrate_task: task perf:32685 [120] from: 1 to: 11
perf-32685 [001] 0.000000: sched_process_fork: parent perf:32685 child perf:32686
true-32686 [011] 0.000000: sched_wakeup: task migration/11:25 [0] success=1 [011]
true-32686 [015] 0.000000: sched_wakeup: task distccd:12793 [125] success=1 [015]
true-32686 [015] 0.000000: sched_wakeup: task distccd:12793 [125] success=1 [015]
perf-32685 [001] 0.000000: sched_switch: task perf:32685 [120] (S) ==> swapper:0 [140]
true-32686 [011] 0.000000: sched_switch: task perf:32686 [120] (R) ==> migration/11:25 [0]
true-32686 [015] 0.000000: sched_switch: task perf:32686 [120] (R) ==> distccd:12793 [125]
true-32686 [015] 0.000000: sched_switch: task true:32686 [120] (R) ==> distccd:12793 [125]
true-32686 [015] 0.000000: sched_process_exit: task true:32686 [120]
true-32686 [015] 0.000000: sched_stat_wait: task: distccd:12793 wait: 6767985949080 [ns]
true-32686 [015] 0.000000: sched_stat_wait: task: distccd:12793 wait: 6767986139446 [ns]
true-32686 [015] 0.000000: sched_stat_sleep: task: distccd:12793 sleep: 132844 [ns]
true-32686 [015] 0.000000: sched_stat_sleep: task: distccd:12793 sleep: 131724 [ns]

So we can now see how this workload migrated between CPUs.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

---
tools/perf/builtin-record.c | 4 +++-
tools/perf/builtin-trace.c | 9 ++++++++-
2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index add514d..ff93f8e 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -403,8 +403,10 @@ static void create_counter(int counter, int cpu, pid_t pid)
if (call_graph)
attr->sample_type |= PERF_SAMPLE_CALLCHAIN;

- if (raw_samples)
+ if (raw_samples) {
attr->sample_type |= PERF_SAMPLE_RAW;
+ attr->sample_type |= PERF_SAMPLE_CPU;
+ }

attr->mmap = track;
attr->comm = track;
diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 8247fd0..bbe4c44 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -58,12 +58,19 @@ process_sample_event(event_t *event, unsigned long offset, unsigned long head)
struct dso *dso = NULL;
struct thread *thread;
u64 ip = event->ip.ip;
+ u32 cpu = -1;
u64 period = 1;
void *more_data = event->ip.__more_data;
int cpumode;

thread = threads__findnew(event->ip.pid, &threads, &last_match);

+ if (sample_type & PERF_SAMPLE_CPU) {
+ cpu = *(u32 *)more_data;
+ more_data += sizeof(u32);
+ more_data += sizeof(u32); /* reserved */
+ }
+
if (sample_type & PERF_SAMPLE_PERIOD) {
period = *(u64 *)more_data;
more_data += sizeof(u64);
@@ -120,7 +127,7 @@ process_sample_event(event_t *event, unsigned long offset, unsigned long head)
* field, although it should be the same than this perf
* event pid
*/
- print_event(0, raw->data, raw->size, 0, thread->comm);
+ print_event(cpu, raw->data, raw->size, 0, thread->comm);
}
total += period;