[PATCH V7 4/6] arm64/perf: Add branch stack support in struct pmu_hw_events

Anshuman Khandual
2023-01-05T18:51:19Z

This adds branch records buffer pointer in 'struct pmu_hw_events' which can
be used to capture branch records during PMU interrupt. This percpu pointer
here needs to be allocated first before usage.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
---
include/linux/perf/arm_pmu.h | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/include/linux/perf/arm_pmu.h b/include/linux/perf/arm_pmu.h
index 64e1b2594025..9184f9b33740 100644
--- a/include/linux/perf/arm_pmu.h
+++ b/include/linux/perf/arm_pmu.h
@@ -44,6 +44,13 @@ static_assert((PERF_EVENT_FLAG_ARCH & ARMPMU_EVT_47BIT) == ARMPMU_EVT_47BIT);
}, \
}

+#define MAX_BRANCH_RECORDS 64
+
+struct branch_records {
+ struct perf_branch_stack branch_stack;
+ struct perf_branch_entry branch_entries[MAX_BRANCH_RECORDS];
+};
+
/* The events for a given PMU register set. */
struct pmu_hw_events {
/*
@@ -70,6 +77,8 @@ struct pmu_hw_events {
struct arm_pmu *percpu_pmu;

int irq;
+
+ struct branch_records *branches;
};

enum armpmu_attr_groups {
--
2.25.1