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J . Mercier" , Martin Liu , Minchan Kim , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Michal Hocko Subject: Re: [PATCH v3] mm: vmscan: abort proactive reclaim early when freezing for suspend Message-ID: References: <20260717181252.2277818-1-richardycc@google.com> MIME-Version: 1.0 In-Reply-To: <20260717181252.2277818-1-richardycc@google.com> X-Scanned-By: MIMEDefang 3.6 on 10.30.177.95 X-Mimecast-MFC-PROC-ID: R_lkXtN9kW6dG8k6jjCeExVoexS4QjANkVtPZXO9VIE_1784314051 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: CB2BDC0007 X-Stat-Signature: gxjj986hncyokt8jw7t379obdzp5doej X-HE-Tag: 1784314057-983429 X-HE-Meta: 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 t9Pm5nna MFGGegQggggy0AZ+iPibGmFwBNYwPSN+AiLNpoIInFqNluwuPBDzUjlyb8Cb6CSKReKSvBzXStYv4bZ4guFA9he2csXeEG7a3zwxaOgCEGjUAQjR7ZS/QvMxrs3v31wVWA/+4WB0xcsMDUbwCZxHhJ0AAKGxLw14NmY7TFK0Z1de06B7wkBvV6H9uwMUMyeqURQpu9YE+AFQ04hWNJgzP5fmZplRQPC3K1g/znu3+6JhdWKRcLcgE2muAIs0xR25cJBCHDMqG0fewVdFWNMsMufmc+mcoePc8+X5bpwq7mSxtxasFk3/a40a+RJpK0wpbqX5Ln7qgtnASKJGPDZQIYWMmC0bFFPHbTK/J Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 07/17, Richard Chang wrote: > > v3: Return -ERESTARTSYS instead of -EINTR in user_proactive_reclaim Yes, this change LGTM, but ... > + /* > + * Return -ERESTARTSYS to allow the freezer to interrupt the > + * task. The syscall will be transparently restarted upon > + * resume. Real signals (e.g. SIGINT) will be automatically > + * converted to -EINTR by the signal layer. > + */ ... the comment looks a bit misleading... So, if the signal is "real" and has a handler, handle_signal() does case -ERESTARTSYS: if (!(ksig->ka.sa.sa_flags & SA_RESTART)) { regs->ax = -EINTR; break; } fallthrough; case -ERESTARTNOINTR: regs->ax = regs->orig_ax; regs->ip -= 2; break; If SA_RESTART is set, the syscall will be restarted after return from signal handler. Oleg.