On Friday 09 December 2016 12:10 AM, Hari Bathini wrote:
Hi Peter,
Sorry for taking so long to respond...
On Thursday 24 November 2016 08:40 PM, Peter Zijlstra wrote:
On Thu, Nov 24, 2016 at 08:14:29PM +0530, Hari Bathini wrote:
@@ -862,6 +875,19 @@ enum perf_event_type {
*/
PERF_RECORD_SWITCH_CPU_WIDE = 15,
+ /*
+ * struct {
+ * struct perf_event_header header;
+ *
+ * u32 pid, tid;
+ * u64 time;
pid,tid and time are already present in sample_id. Many of the 'legacy'
record have redundant information since we added sample_id, but most of
the new ones haven't and rely on sample_all being set.
I tried using pid/tid from sample data, but realized that pid/tid in
event_id
could be different from the one in sample data, at least for
fork/namespaces
events, since __perf_event_header__init_id( ) that updates the sample
data
is getting the pid/tid of current task.
I am not sure if it is advisable to change
__perf_event_header__init_id( ) for this..?
Hi Peter,
Adding task parameter to __perf_event_header__init_id( ) and doing
something like..
perf_event_pid(event, task ? task : current)
perf_event_tid(event, task ? task : current)
Also, for synthesized events, sample_id is not updated currently.
Working on it as that
is needed if we want to relay on pid, tid values from sample_id. Let me
know, if this is
what you had in mind or something else altogether..
Thanks
Hari
