From: Tejun Heo Subject: Re: [PATCH for-4.20-fixes] cgroup: fix CSS_TASK_ITER_PROCS Date: Tue, 20 Nov 2018 08:13:19 -0800 Message-ID: <20181120161319.GR2509588@devbig004.ftw2.facebook.com> References: <20181108201515.GC2509588@devbig004.ftw2.facebook.com> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=bgwKqPKTuNIZc8ZNsu7oVmFBZQ8IygAJo53SBFGFiIQ=; b=V1bA6YEeXrAtNVoYUUFf0jskgCq4F6fh+L1tUr4yzb8+4XauJAgjqEJT4vZI8S7ryQ g7yt1a3lwu4fXWSLPSLAO7F/D9UgZkLc9uVpsqIi+bszk5j0RQlf4j4oTC874itO9Lvc 4fxRpShIc5ARo8KqCeVpAQY5Cx/MKFkuAeEXM3hGPRGI+pa1kZ0adZq+4RLqhKTU9SAO JkjtMmTV1v5movdnpcR7sg4IYmloHCavOT/Hmit++RUJfNucmgbnbNyEF4R5tpe4sKQ+ ufzT0OaMpBZumOBDp6Q52NQ2isscfdZb0uhux60HLPaVJkUlAVyfyBx8Ty1te+A094jm 0TCQ== Content-Disposition: inline In-Reply-To: <20181108201515.GC2509588@devbig004.ftw2.facebook.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: "Michael Kerrisk (man-pages)" Cc: "open list:CONTROL GROUP (CGROUP)" , lkml , kernel-team@fb.com On Thu, Nov 08, 2018 at 12:15:15PM -0800, Tejun Heo wrote: > CSS_TASK_ITER_PROCS implements process-only iteration by making > css_task_iter_advance() skip tasks which aren't threadgroup leaders; > however, when an iteration is started css_task_iter_start() calls the > inner helper function css_task_iter_advance_css_set() instead of > css_task_iter_advance(). As the helper doesn't have the skip logic, > when the first task to visit is a non-leader thread, it doesn't get > skipped correctly as shown in the following example. Applied to cgroup/for-4.20-fixes. Thanks. -- tejun