From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qg0-f54.google.com (mail-qg0-f54.google.com [209.85.192.54]) by kanga.kvack.org (Postfix) with ESMTP id 3F8536B006C for ; Tue, 12 May 2015 10:40:37 -0400 (EDT) Received: by qgdy78 with SMTP id y78so5156393qgd.0 for ; Tue, 12 May 2015 07:40:37 -0700 (PDT) Received: from mail-qk0-x22d.google.com (mail-qk0-x22d.google.com. [2607:f8b0:400d:c09::22d]) by mx.google.com with ESMTPS id b123si16330216qka.20.2015.05.12.07.40.35 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 12 May 2015 07:40:36 -0700 (PDT) Received: by qku63 with SMTP id 63so6856098qku.3 for ; Tue, 12 May 2015 07:40:35 -0700 (PDT) Date: Tue, 12 May 2015 10:40:32 -0400 From: Tejun Heo Subject: Re: [RFC PATCH] PM, freezer: Don't thaw when it's intended frozen processes Message-ID: <20150512144032.GN11388@htj.duckdns.org> References: <20150507064557.GA26928@july> <20150507154212.GA12245@htj.duckdns.org> <20150508152513.GB28439@htj.duckdns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Krzysztof Kozlowski Cc: Kyungmin Park , linux-mm , Andrew Morton , "\\Rafael J. Wysocki\\" , David Rientjes , Johannes Weiner , Oleg Nesterov , Cong Wang , LKML , Linux PM list On Mon, May 11, 2015 at 03:33:10PM +0900, Krzysztof Kozlowski wrote: > > Yes, they should and I'm not sure why what you're saying is happening > > because freezing() test done from the frozen tasks themselves should > > keep them in the freezer. Which kernel version did you test? Can you > > please verify it against a recent kernel? > > I tested it on v4.1-rc3 and next-20150508. > > Task was moved to frozen cgroup: > ----- > root@localhost:/sys/fs/cgroup/freezer/frozen# grep . * > cgroup.clone_children:0 > cgroup.procs:2750 > freezer.parent_freezing:0 > freezer.self_freezing:1 > freezer.state:FROZEN > notify_on_release:0 > tasks:2750 > tasks:2773 > ----- > > Unfortunately during system resume the process was woken up. The "if > (frozen(p))" check was true. Is it expected behaviour? It isn't optimal but doesn't break anything either. Whether a task stays in the freezer or not is solely decided by freezing() test by the task itself. Being woken up spuriously doesn't break anything. Thanks. -- tejun -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org