linux-kernel - Re: [PATCH 34/41] perf evlist: Add 'system

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <53E9AB9B.2080004@intel.com>
Date:	Tue, 12 Aug 2014 08:52:27 +0300
From:	Adrian Hunter <adrian.hunter@...el.com>
To:	Jiri Olsa <jolsa@...hat.com>
CC:	Arnaldo Carvalho de Melo <acme@...nel.org>,
	Peter Zijlstra <peterz@...radead.org>,
	linux-kernel@...r.kernel.org, David Ahern <dsahern@...il.com>,
	Frederic Weisbecker <fweisbec@...il.com>,
	Namhyung Kim <namhyung@...il.com>,
	Paul Mackerras <paulus@...ba.org>,
	Stephane Eranian <eranian@...gle.com>
Subject: Re: [PATCH 34/41] perf evlist: Add 'system_wide' option

On 08/11/2014 04:12 PM, Jiri Olsa wrote:
> On Mon, Jul 14, 2014 at 01:02:58PM +0300, Adrian Hunter wrote:
>> Add an option to cause a selected event
>> to be opened always without a pid when
>> configured by perf_evsel__config().
>>
>> This is needed when using the sched_switch
>> tracepoint to follow object code execution.
>> sched_switch occurs before the task
>> switch and so it cannot record it in a
>> context limited to that task.  Note
>> that also means that sched_switch is
>> useless when capturing data per-thread,
>> as is the 'context-switches' software
>> event for the same reason.
>>
>> Signed-off-by: Adrian Hunter <adrian.hunter@...el.com>
>> ---
>>  tools/perf/util/evlist.c | 45 +++++++++++++++++++++++++++++++++++++--------
>>  tools/perf/util/evsel.c  | 31 ++++++++++++++++++++++++++-----
>>  tools/perf/util/evsel.h  |  1 +
>>  3 files changed, 64 insertions(+), 13 deletions(-)
>>
>> diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
>> index 282e83e..c295b7b 100644
>> --- a/tools/perf/util/evlist.c
>> +++ b/tools/perf/util/evlist.c
>> @@ -265,17 +265,27 @@ int perf_evlist__add_newtp(struct perf_evlist *evlist,
>>  	return 0;
>>  }
>>  
>> +static int perf_evlist__nr_threads(struct perf_evlist *evlist,
>> +				   struct perf_evsel *evsel)
>> +{
>> +	if (evsel->system_wide)
>> +		return 1;
>> +	else
>> +		return thread_map__nr(evlist->threads);
>> +}
> 
> how is 'evsel->system_wide' set?

Intel PT sets it for the sched_switch event.


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/