From:   Anshuman Khandual <anshuman.khandual@arm.com>
To:     linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        will@kernel.org, catalin.marinas@arm.com, mark.rutland@arm.com
Cc:     Anshuman Khandual <anshuman.khandual@arm.com>,
        Mark Brown <broonie@kernel.org>,
        James Clark <james.clark@arm.com>,
        Rob Herring <robh@kernel.org>, Marc Zyngier <maz@kernel.org>,
        Suzuki Poulose <suzuki.poulose@arm.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        linux-perf-users@vger.kernel.org
Subject: [PATCH V8 4/6] arm64/perf: Add branch stack support in struct pmu_hw_events
Date:   Mon, 23 Jan 2023 18:29:54 +0530
Message-Id: <20230123125956.1350336-5-anshuman.khandual@arm.com>
In-Reply-To: <20230123125956.1350336-1-anshuman.khandual@arm.com>
References: <20230123125956.1350336-1-anshuman.khandual@arm.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

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 78cb1c895ab9..bd6dc6d0bd44 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