From a9a931e2666878343782c82d7d55cc173ddeb3e9 Mon Sep 17 00:00:00 2001 From: Kan Liang Date: Thu, 1 Sep 2022 06:09:56 -0700 Subject: perf: Use sample_flags for branch stack Use the new sample_flags to indicate whether the branch stack is filled by the PMU driver. Remove the br_stack from the perf_sample_data_init() to minimize the number of cache lines touched. Signed-off-by: Kan Liang Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20220901130959.1285717-4-kan.liang@linux.intel.com --- kernel/events/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel/events') diff --git a/kernel/events/core.c b/kernel/events/core.c index c9b9cb79231a..104c0c9f4e6f 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -7052,7 +7052,7 @@ void perf_output_sample(struct perf_output_handle *handle, } if (sample_type & PERF_SAMPLE_BRANCH_STACK) { - if (data->br_stack) { + if (data->sample_flags & PERF_SAMPLE_BRANCH_STACK) { size_t size; size = data->br_stack->nr @@ -7358,7 +7358,7 @@ void perf_prepare_sample(struct perf_event_header *header, if (sample_type & PERF_SAMPLE_BRANCH_STACK) { int size = sizeof(u64); /* nr */ - if (data->br_stack) { + if (data->sample_flags & PERF_SAMPLE_BRANCH_STACK) { if (perf_sample_save_hw_index(event)) size += sizeof(u64); -- cgit 1.4.1