Commit 3749d33e authored by Namhyung Kim's avatar Namhyung Kim Committed by Peter Zijlstra
Browse files

perf: Use sample_flags for callchain 



So that it can call perf_callchain() only if needed.  Historically it used
__PERF_SAMPLE_CALLCHAIN_EARLY but we can do that with sample_flags in the
struct perf_sample_data.

Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220908214104.3851807-1-namhyung@kernel.org
parent fae9ebde

arch/x86/events/amd/ibs.c

+3 −1
Original line number Diff line number Diff line
@@ -798,8 +798,10 @@ static int perf_ibs_handle_irq(struct perf_ibs *perf_ibs, struct pt_regs *iregs) 
	 * recorded as part of interrupt regs. Thus we need to use rip from

	 * interrupt regs while unwinding call stack.

	 */

	if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN)

	if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) {

		data.callchain = perf_callchain(event, iregs);

		data.sample_flags |= PERF_SAMPLE_CALLCHAIN;

	}



	throttle = perf_event_overflow(event, &data, &regs);

out:

arch/x86/events/intel/ds.c

+6 −2
Original line number Diff line number Diff line
@@ -1546,8 +1546,10 @@ static void setup_pebs_fixed_sample_data(struct perf_event *event, 
	 * previous PMI context or an (I)RET happened between the record and

	 * PMI.

	 */

	if (sample_type & PERF_SAMPLE_CALLCHAIN)

	if (sample_type & PERF_SAMPLE_CALLCHAIN) {

		data->callchain = perf_callchain(event, iregs);

		data->sample_flags |= PERF_SAMPLE_CALLCHAIN;

	}



	/*

	 * We use the interrupt regs as a base because the PEBS record does not
@@ -1719,8 +1721,10 @@ static void setup_pebs_adaptive_sample_data(struct perf_event *event, 
	 * previous PMI context or an (I)RET happened between the record and

	 * PMI.

	 */

	if (sample_type & PERF_SAMPLE_CALLCHAIN)

	if (sample_type & PERF_SAMPLE_CALLCHAIN) {

		data->callchain = perf_callchain(event, iregs);

		data->sample_flags |= PERF_SAMPLE_CALLCHAIN;

	}



	*regs = *iregs;

	/* The ip in basic is EventingIP */

kernel/events/core.c

+1 −1
Original line number Diff line number Diff line
@@ -7320,7 +7320,7 @@ void perf_prepare_sample(struct perf_event_header *header, 
	if (sample_type & PERF_SAMPLE_CALLCHAIN) {

		int size = 1;



		if (!(sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY))

		if (filtered_sample_type & PERF_SAMPLE_CALLCHAIN)

			data->callchain = perf_callchain(event, regs);



		size += data->callchain->nr;