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Wysocki" , Peter Zijlstra , David Hildenbrand , Michal Hocko , Jonathan Corbet , Ingo Molnar , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , len brown , pavel machek , Kees Cook , Andrew Morton , Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Catalin Marinas , Nico Pache , xu xin , wangfushuai , Andrii Nakryiko , Christian Brauner , Thomas Gleixner , Jeff Layton , Al Viro , Adrian Ratiu , linux-pm@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org References: <20250807121418.139765-1-zhangzihuan@kylinos.cn> <20250807121418.139765-7-zhangzihuan@kylinos.cn> <20250808142948.GA21685@redhat.com> From: Zihuan Zhang In-Reply-To: <20250808142948.GA21685@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 7F455180006 X-Stat-Signature: 5x9bfanh7yjgkwyyfxqpmmjcxkt8ara6 X-Rspam-User: X-HE-Tag: 1754904575-441172 X-HE-Meta: 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 lLdpuxL4 75GNGwV11oprx5LQE1BvB4Yt+E5xdufgyB7rB42JBoUeFcBkGxtE/hZA5BFIZRws6zL5L5iqWTvSKlBjSumQWieY3Q1+pyFOQrkcpztdWwSThidRZI6bu5gBPKjAZ1ZpTOE9taeEDRM/QHTs= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: =E5=9C=A8 2025/8/8 22:29, Oleg Nesterov =E5=86=99=E9=81=93: > On 08/07, Zihuan Zhang wrote: >> @@ -6980,6 +6981,7 @@ void __noreturn do_task_dead(void) >> current->flags |=3D PF_NOFREEZE; >> >> __schedule(SM_NONE); >> + freeze_set_default_priority(current, FREEZE_PRIORITY_NEVER); >> BUG(); > But this change has no effect? > > Firstly, this last __schedule() should not return, note the BUG() we ha= ve. > > Secondly, this zombie is already PF_NOFREEZE, freeze_task() will return > false anyway. Sorry, but in our tests with a large number of zombie tasks, returning=20 early reduced the overhead. Even though freeze_task() would return false=20 for PF_NOFREEZE, skipping the extra path still saved time in our=20 suspend/freezer loop. > Oleg. >