The following commit has been merged into the perf/urgent branch of tip:

Commit-ID: 90befef5a9e820ccccc33181ec14c015980300cc Gitweb: https://git.kernel.org/tip/90befef5a9e820ccccc33181ec14c015980300cc Author: Namhyung Kim namhyung@kernel.org AuthorDate: Wed, 26 Apr 2023 20:05:27 -07:00 Committer: Peter Zijlstra peterz@infradead.org CommitterDate: Mon, 08 May 2023 10:58:26 +02:00

perf/x86: Fix missing sample size update on AMD BRS

It missed to convert a PERF_SAMPLE_BRANCH_STACK user to call the new perf_sample_save_brstack() helper in order to update the dyn_size. This affects AMD Zen3 machines with the branch-brs event.

Fixes: eb55b455ef9c ("perf/core: Add perf_sample_save_brstack() helper") Signed-off-by: Namhyung Kim namhyung@kernel.org Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20230427030527.580841-1-namhyung@kernel.org --- arch/x86/events/core.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index d096b04..9d24870 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -1703,10 +1703,8 @@ int x86_pmu_handle_irq(struct pt_regs *regs)

perf_sample_data_init(&data, 0, event->hw.last_period);

- if (has_branch_stack(event)) { - data.br_stack = &cpuc->lbr_stack; - data.sample_flags |= PERF_SAMPLE_BRANCH_STACK; - } + if (has_branch_stack(event)) + perf_sample_save_brstack(&data, event, &cpuc->lbr_stack);

if (perf_event_overflow(event, &data, regs)) x86_pmu_stop(event, 0);