From: Peter Zijlstra <peterz@infradead.org>
To: Minwoo Ahn <mwahn402@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>,
Arnaldo Carvalho de Melo <acme@kernel.org>,
Namhyung Kim <namhyung@kernel.org>,
Mark Rutland <mark.rutland@arm.com>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
Jiri Olsa <jolsa@kernel.org>, Ian Rogers <irogers@google.com>,
Adrian Hunter <adrian.hunter@intel.com>,
James Clark <james.clark@linaro.org>,
Jinkyu Jeong <jinkyu@yonsei.ac.kr>,
linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v4] perf/core: Fix sampling period inconsistency across CPU migration
Date: Mon, 4 May 2026 10:08:32 +0200 [thread overview]
Message-ID: <20260504080832.GO3126523@noisy.programming.kicks-ass.net> (raw)
In-Reply-To: <20260429095134.10049-1-mwahn402@gmail.com>
On Wed, Apr 29, 2026 at 09:51:34AM +0000, Minwoo Ahn wrote:
>
> When per-task software events are sampled, period_left is not
> managed consistently when task migration happens. The perf_event
> may observe a different hw_perf_event::period_left on the new CPU,
> breaking the sampling periodicity. Even if a task was near its
> sampling point, it would use a stale period_left after migration.
How? This is just vague words, not actually saying anything of
substance.
> Introduce struct perf_task_context as a per-task container to
How can you propose a solution to a non-defined problem?
next prev parent reply other threads:[~2026-05-04 8:08 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-04-29 9:51 [PATCH v4] perf/core: Fix sampling period inconsistency across CPU migration Minwoo Ahn
2026-05-04 8:08 ` Peter Zijlstra [this message]
2026-05-04 13:52 ` Minwoo Ahn
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