From: Peter Zijlstra <peterz@infradead.org>
To: Libo Chen <libo.chen@oracle.com>
Cc: "Chen, Yu C" <yu.c.chen@intel.com>,
Michal Hocko <mhocko@suse.com>, Ingo Molnar <mingo@redhat.com>,
Juri Lelli <juri.lelli@redhat.com>,
Vincent Guittot <vincent.guittot@linaro.org>,
Dietmar Eggemann <dietmar.eggemann@arm.com>,
Steven Rostedt <rostedt@goodmis.org>,
Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
Valentin Schneider <vschneid@redhat.com>,
Andrew Morton <akpm@linux-foundation.org>,
Tim Chen <tim.c.chen@intel.com>,
linux-kernel@vger.kernel.org, Jirka Hladky <jhladky@redhat.com>,
Srikanth Aithal <Srikanth.Aithal@amd.com>,
Suneeth D <Suneeth.D@amd.com>
Subject: Re: [PATCH] sched/numa: Fix NULL pointer access to mm_struct durng task swap
Date: Fri, 4 Jul 2025 10:26:35 +0200 [thread overview]
Message-ID: <20250704082635.GD2001818@noisy.programming.kicks-ass.net> (raw)
In-Reply-To: <12b84e27-f9b1-477e-8e56-4b7c6727e86b@oracle.com>
On Thu, Jul 03, 2025 at 04:35:42PM -0700, Libo Chen wrote:
> Probably not as bad as you may think. Systems with one NUMA node or NUMA
> balancing disabled (which will be most of the machines) won't be affected
> by this at all , task_numa_migrate() is also ratelimited so it doesn't get
> touched nearly as often as most of other scheduler events.
>
> If this is on a really hot and critical path that most of us have to take,
> such as wakeup, I won't argue with you at all. I don't want to be too
> persistent here, it's fine to use eBPF with the existing tracepoints. I
> just think this is convenient and doesn't really hurt those who don't care
> about these numbers.
Its not about this one path per-se, more a general rant on the 'merit'
of endlessly adding statistics and accounting to code.
prev parent reply other threads:[~2025-07-04 8:26 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-07-02 16:32 [PATCH] sched/numa: Fix NULL pointer access to mm_struct durng task swap Chen Yu
2025-07-02 21:08 ` Andrew Morton
2025-07-03 9:24 ` Chen, Yu C
2025-07-03 7:18 ` Michal Hocko
2025-07-03 9:37 ` Chen, Yu C
2025-07-03 11:51 ` Michal Hocko
2025-07-03 11:55 ` Peter Zijlstra
2025-07-03 7:26 ` Peter Zijlstra
2025-07-03 9:28 ` Michal Hocko
2025-07-03 11:50 ` Peter Zijlstra
2025-07-03 12:01 ` Michal Hocko
2025-07-03 12:04 ` Chen, Yu C
2025-07-03 12:20 ` Libo Chen
2025-07-03 12:36 ` Peter Zijlstra
2025-07-03 13:38 ` Chen, Yu C
2025-07-03 14:01 ` Peter Zijlstra
2025-07-04 5:57 ` Chen, Yu C
2025-07-03 13:57 ` Libo Chen
2025-07-03 14:18 ` Peter Zijlstra
2025-07-03 23:35 ` Libo Chen
2025-07-04 8:26 ` Peter Zijlstra [this message]
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