[V4,3/7] arm64/perf: Update struct pmu_hw_events for BRBE

Message ID 20221017055713.451092-4-anshuman.khandual@arm.com
State New
Headers
Series arm64/perf: Enable branch stack sampling |

Commit Message

Anshuman Khandual Oct. 17, 2022, 5:57 a.m. UTC
  A single perf event instance BRBE related contexts and data will be tracked
in struct pmu_hw_events. Hence update the structure to accommodate required
details related to BRBE.

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>
---
 drivers/perf/arm_pmu.c       |  1 +
 include/linux/perf/arm_pmu.h | 27 +++++++++++++++++++++++++++
 2 files changed, 28 insertions(+)
  

Patch

diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
index 3f07df5a7e95..5048a500441e 100644
--- a/drivers/perf/arm_pmu.c
+++ b/drivers/perf/arm_pmu.c
@@ -905,6 +905,7 @@  static struct arm_pmu *__armpmu_alloc(gfp_t flags)
 
 		events = per_cpu_ptr(pmu->hw_events, cpu);
 		raw_spin_lock_init(&events->pmu_lock);
+		events->branches = kmalloc(sizeof(struct brbe_records), flags);
 		events->percpu_pmu = pmu;
 	}
 
diff --git a/include/linux/perf/arm_pmu.h b/include/linux/perf/arm_pmu.h
index 67a6d59786f2..bda0d9984a98 100644
--- a/include/linux/perf/arm_pmu.h
+++ b/include/linux/perf/arm_pmu.h
@@ -44,6 +44,16 @@  static_assert((PERF_EVENT_FLAG_ARCH & ARMPMU_EVT_47BIT) == ARMPMU_EVT_47BIT);
 	},								\
 }
 
+/*
+ * Maximum branch records in BRBE
+ */
+#define BRBE_MAX_ENTRIES 64
+
+struct brbe_records {
+	struct perf_branch_stack	brbe_stack;
+	struct perf_branch_entry	brbe_entries[BRBE_MAX_ENTRIES];
+};
+
 /* The events for a given PMU register set. */
 struct pmu_hw_events {
 	/*
@@ -70,6 +80,23 @@  struct pmu_hw_events {
 	struct arm_pmu		*percpu_pmu;
 
 	int irq;
+
+	/* Detected BRBE attributes */
+	bool				brbe_v1p1;
+	int				brbe_cc;
+	int				brbe_nr;
+	int				brbe_format;
+
+	/* Evaluated BRBE configuration */
+	u64				brbfcr;
+	u64				brbcr;
+
+	/* Tracked BRBE context */
+	unsigned int			brbe_users;
+	void				*brbe_context;
+
+	/* Captured BRBE buffer - copied as is into perf_sample_data */
+	struct brbe_records		*branches;
 };
 
 enum armpmu_attr_groups {