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[195.250.132.146]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a729d72032csm34726766b.83.2024.06.27.00.56.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 27 Jun 2024 00:56:47 -0700 (PDT) Date: Thu, 27 Jun 2024 09:56:46 +0200 From: Michal Hocko To: Oleg Nesterov Cc: Andrew Morton , Christian Brauner , "Eric W. Biederman" , Jens Axboe , Jinliang Zheng , Mateusz Guzik , Matthew Wilcox , Tycho Andersen , linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] memcg: mm_update_next_owner: kill the "retry" logic Message-ID: References: <20240626152835.GA17910@redhat.com> <20240626152924.GA17933@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240626152924.GA17933@redhat.com> On Wed 26-06-24 17:29:24, Oleg Nesterov wrote: > @@ -446,7 +463,6 @@ void mm_update_next_owner(struct mm_struct *mm) > { > struct task_struct *c, *g, *p = current; > > -retry: > /* > * If the exiting or execing task is not the owner, it's > * someone else's problem. > @@ -468,16 +484,16 @@ void mm_update_next_owner(struct mm_struct *mm) > * Search in the children > */ > list_for_each_entry(c, &p->children, sibling) { > - if (c->mm == mm) > - goto assign_new_owner; > + if (c->mm == mm && try_to_set_owner(c, mm)) > + goto ret; You need to unlock tasklist_lock, right? Same for other goto ret. Other than that the cleanup makes sense and it makes the code much more easier to follow. It should still die but it can do so in a better shape. -- Michal Hocko SUSE Labs