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From: Junxiao Chang <junxiao.chang@intel.com>
To: peterz@infradead.org, mingo@redhat.com, acme@kernel.org,
	namhyung@kernel.org, mark.rutland@arm.com,
	alexander.shishkin@linux.intel.com, jolsa@kernel.org,
	irogers@google.com, adrian.hunter@intel.com,
	james.clark@linaro.org, linux-perf-users@vger.kernel.org,
	linux-kernel@vger.kernel.org
Cc: bigeasy@linutronix.de, junxiao.chang@intel.com
Subject: [PATCH 0/1] allow trace events to be accessed from any CPU
Date: Thu, 28 May 2026 08:51:35 +0800	[thread overview]
Message-ID: <20260528005136.1906479-1-junxiao.chang@intel.com> (raw)

The issue was reproduced while debugging real-time scheduling
performance. An extra SMP IPI is triggered when using perf stat
to collect trace event statistics.

Trace events should be accessible from any CPU without requiring
an IPI when the current CPU differs from the event CPU.

Set the trace event PMU scope to PERF_PMU_SCOPE_SYS_WIDE so that
trace events can be accessed system-wide. With this change, no
extra SMP IPI is triggered even when the current CPU differs from
the event CPU.

Junxiao Chang (1):
  perf/core: allow trace events to be accessed from any CPU

 kernel/events/core.c | 1 +
 1 file changed, 1 insertion(+)

-- 
2.43.0


             reply	other threads:[~2026-05-27  0:57 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-05-28  0:51 Junxiao Chang [this message]
2026-05-28  0:51 ` [PATCH 1/1] perf/core: allow trace events to be accessed from any CPU Junxiao Chang
2026-05-27  1:52   ` sashiko-bot

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