Commit 98402807 authored by Frederic Weisbecker's avatar Frederic Weisbecker
Browse files

perf: Introduce a new "round of buffers read" pseudo event 



In order to provide a more rubust and deterministic reordering
algorithm, we need to know when we reach a point where we just
did a pass through over every counter buffers to read every thing
they had.

This patch introduces a new PERF_RECORD_FINISHED_ROUND pseudo event
that only consist in an event header and doesn't need to contain
anything.

Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
parent e157eb83

tools/perf/builtin-record.c

+24 −10
Original line number Diff line number Diff line
@@ -494,6 +494,29 @@ static void event__synthesize_guest_os(struct machine *machine, void *data) 
		       " relocation symbol.\n", machine->pid);

}



static struct perf_event_header finished_round_event = {

	.size = sizeof(struct perf_event_header),

	.type = PERF_RECORD_FINISHED_ROUND,

};



static void mmap_read_all(void)

{

	int i, counter, thread;



	for (i = 0; i < nr_cpu; i++) {

		for (counter = 0; counter < nr_counters; counter++) {

			for (thread = 0; thread < thread_num; thread++) {

				if (mmap_array[i][counter][thread].base)

					mmap_read(&mmap_array[i][counter][thread]);

			}



		}

	}



	if (perf_header__has_feat(&session->header, HEADER_TRACE_INFO))

		write_output(&finished_round_event, sizeof(finished_round_event));

}



static int __cmd_record(int argc, const char **argv)

{

	int i, counter;
@@ -726,16 +749,7 @@ static int __cmd_record(int argc, const char **argv) 
		int hits = samples;

		int thread;



		for (i = 0; i < nr_cpu; i++) {

			for (counter = 0; counter < nr_counters; counter++) {

				for (thread = 0;

					thread < thread_num; thread++) {

					if (mmap_array[i][counter][thread].base)

						mmap_read(&mmap_array[i][counter][thread]);

				}



			}

		}

		mmap_read_all();



		if (hits == samples) {

			if (done)

tools/perf/util/event.h

+2 −1
Original line number Diff line number Diff line
@@ -84,11 +84,12 @@ struct build_id_event { 
	char			 filename[];

};



enum perf_header_event_type { /* above any possible kernel type */

enum perf_user_event_type { /* above any possible kernel type */

	PERF_RECORD_HEADER_ATTR			= 64,

	PERF_RECORD_HEADER_EVENT_TYPE		= 65,

	PERF_RECORD_HEADER_TRACING_DATA		= 66,

	PERF_RECORD_HEADER_BUILD_ID		= 67,

	PERF_RECORD_FINISHED_ROUND		= 68,

	PERF_RECORD_HEADER_MAX

};

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