Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1031370Ab0B1BPQ (ORCPT ); Sat, 27 Feb 2010 20:15:16 -0500 Received: from ozlabs.org ([203.10.76.45]:54074 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031049Ab0B1BPO (ORCPT ); Sat, 27 Feb 2010 20:15:14 -0500 Date: Sun, 28 Feb 2010 12:11:23 +1100 From: Anton Blanchard To: Tejun Heo Cc: torvalds@linux-foundation.org, mingo@elte.hu, peterz@infradead.org, awalls@radix.net, linux-kernel@vger.kernel.org, jeff@garzik.org, akpm@linux-foundation.org, jens.axboe@oracle.com, rusty@rustcorp.com.au, cl@linux-foundation.org, dhowells@redhat.com, arjan@linux.intel.com, avi@redhat.com, johannes@sipsolutions.net, andi@firstfloor.org, oleg@redhat.com Subject: Re: [PATCHSET] workqueue: concurrency managed workqueue, take#4 Message-ID: <20100228011123.GC13594@kryten> References: <1267187000-18791-1-git-send-email-tj@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1267187000-18791-1-git-send-email-tj@kernel.org> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1827 Lines: 39 Hi Tejun, I gave the workqueue patches a spin on PowerPC. I'm particularly interested from an OS jitter perspective, and that these patches wont introduce more jitter. It looks like we reach a steady state of worker threads and arent continually creating and destroying them which is good. This could be a big deal on compute CPUs (CPUs isolated via isol_cpus or cpusets). A few things I've found so far: 1. NR_CPUS > 32 causes issues with the workqueue debugfs code: kernel/workqueue.c:3314: warning: left shift count >= width of type kernel/workqueue.c:3323: warning: left shift count >= width of type kernel/workqueue.c:3323: warning: integer overflow in expression kernel/workqueue.c:3324: warning: enumeration values exceed range of largest integer kernel/workqueue.c: In function ‘wq_debugfs_decode_pos’: kernel/workqueue.c:3336: warning: right shift count is negative kernel/workqueue.c:3337: warning: right shift count is negative kernel/workqueue.c: In function ‘wq_debugfs_next_pos’: kernel/workqueue.c:3435: warning: left shift count is negative kernel/workqueue.c:3436: warning: left shift count is negative kernel/workqueue.c: In function ‘wq_debugfs_start’: kernel/workqueue.c:3455: warning: left shift count >= width of type 2. cifs needs to be converted: fs/cifs/cifsfs.c: In function ‘exit_cifs’: fs/cifs/cifsfs.c:1067: error: ‘system_single_wq’ undeclared (first use in this function) fs/cifs/cifsfs.c:1067: error: (Each undeclared identifier is reported only once fs/cifs/cifsfs.c:1067: error: for each function it appears in.) Anton -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/