From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756347AbbJ2CY5 (ORCPT ); Wed, 28 Oct 2015 22:24:57 -0400 Received: from mail-pa0-f42.google.com ([209.85.220.42]:33962 "EHLO mail-pa0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751237AbbJ2CYz (ORCPT ); Wed, 28 Oct 2015 22:24:55 -0400 Date: Thu, 29 Oct 2015 11:24:47 +0900 From: Tejun Heo To: Tetsuo Handa Cc: cl@linux.com, akpm@linux-foundation.org, mhocko@kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, hannes@cmpxchg.org, mgorman@suse.de Subject: Re: [patch 3/3] vmstat: Create our own workqueue Message-ID: <20151029022447.GB27115@mtj.duckdns.org> References: <20151028024114.370693277@linux.com> <20151028024131.719968999@linux.com> <20151028024350.GA10448@mtj.duckdns.org> <201510282057.JHI87536.OMOFFFLJOHQtVS@I-love.SAKURA.ne.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201510282057.JHI87536.OMOFFFLJOHQtVS@I-love.SAKURA.ne.jp> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, That's weird. On Wed, Oct 28, 2015 at 08:57:28PM +0900, Tetsuo Handa wrote: > [ 272.851035] Showing busy workqueues and worker pools: > [ 272.852583] workqueue events: flags=0x0 > [ 272.853942] pwq 6: cpus=3 node=0 flags=0x0 nice=0 active=1/256 > [ 272.855781] pending: vmw_fb_dirty_flush [vmwgfx] > [ 272.857500] pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 > [ 272.859359] pending: vmpressure_work_fn > [ 272.860840] workqueue events_freezable_power_: flags=0x84 > [ 272.862461] pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=2/256 > [ 272.864479] in-flight: 11286:disk_events_workfn What's this guy doing? Can you get stack dump on 11286 (or whatever is in flight in the next lockup)? > [ 272.866065] pending: disk_events_workfn > [ 272.867587] workqueue vmstat: flags=0x8 > [ 272.868942] pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/256 > [ 272.870785] pending: vmstat_update > [ 272.872248] pool 2: cpus=1 node=0 flags=0x0 nice=0 workers=4 idle: 14 218 43 Thanks. -- tejun