From: Qi Liu <liuqi115@huawei.com>
To: <will@kernel.org>, <mark.rutland@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>,
<linux-kernel@vger.kernel.org>, <linuxarm@huawei.com>
Subject: [PATCH] arm64: perf: Remove redundant initialization in perf_event.c
Date: Thu, 1 Apr 2021 19:16:41 +0800 [thread overview]
Message-ID: <1617275801-1980-1-git-send-email-liuqi115@huawei.com> (raw)
The initialization of value in function armv8pmu_read_hw_counter()
and armv8pmu_read_counter() seem redundant, as they are soon updated.
So, We can remove them.
Signed-off-by: Qi Liu <liuqi115@huawei.com>
---
arch/arm64/kernel/perf_event.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c
index 4658fcf..f594957 100644
--- a/arch/arm64/kernel/perf_event.c
+++ b/arch/arm64/kernel/perf_event.c
@@ -470,9 +470,8 @@ static inline u64 armv8pmu_read_evcntr(int idx)
static inline u64 armv8pmu_read_hw_counter(struct perf_event *event)
{
int idx = event->hw.idx;
- u64 val = 0;
+ u64 val = armv8pmu_read_evcntr(idx);
- val = armv8pmu_read_evcntr(idx);
if (armv8pmu_event_is_chained(event))
val = (val << 32) | armv8pmu_read_evcntr(idx - 1);
return val;
@@ -520,7 +519,7 @@ static u64 armv8pmu_read_counter(struct perf_event *event)
{
struct hw_perf_event *hwc = &event->hw;
int idx = hwc->idx;
- u64 value = 0;
+ u64 value;
if (idx == ARMV8_IDX_CYCLE_COUNTER)
value = read_sysreg(pmccntr_el0);
--
2.8.1
next reply other threads:[~2021-04-01 18:29 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-01 11:16 Qi Liu [this message]
2021-04-01 17:33 ` [PATCH] arm64: perf: Remove redundant initialization in perf_event.c Will Deacon
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