From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx194.postini.com [74.125.245.194]) by kanga.kvack.org (Postfix) with SMTP id 337D36B0062 for ; Mon, 3 Dec 2012 14:07:18 -0500 (EST) Date: Mon, 3 Dec 2012 11:07:15 -0800 From: Zach Brown Subject: Re: [patch] bdi: add a user-tunable cpu_list for the bdi flusher threads Message-ID: <20121203190715.GB1377@lenny.home.zabbo.net> References: <20121130221542.GM18574@lenny.home.zabbo.net> 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: Jeff Moyer Cc: Jens Axboe , linux-kernel@vger.kernel.org, linux-mm@kvack.org On Mon, Dec 03, 2012 at 11:22:31AM -0500, Jeff Moyer wrote: > Jeff Moyer writes: > > >>> + bdi->flusher_cpumask = kmalloc(sizeof(cpumask_t), GFP_KERNEL); > >>> + if (!bdi->flusher_cpumask) > >>> + return -ENOMEM; > >> > >> The bare GFP_KERNEL raises an eyebrow. Some bdi_init() callers like > >> blk_alloc_queue_node() look like they'll want to pass in a gfp_t for the > >> allocation. > > > > I'd be surprised if that was necessary, seeing how every single caller > > of blk_alloc_queue_node passes in GFP_KERNEL. I'll make the change, > > though, there aren't too many callers of bdi_init out there. > > No other callers of bdi_init want anything but GFP_KERNEL. In the case > of blk_alloc_queue_node, even *it* doesn't honor the gfp_t passed in! > Have a look at blkcg_init_queue (called from blk_alloc_queue_node) to > see what I mean. Maybe that's a bug? Heh, indeed. > I've written the patch to modify bdi_init to take a gfp_t, but I'm > actually not in favor of this change, so I'm not going to post it > (unless, of course, you can provide a compelling argument). :-) No argument here, it just jumped out at me in the code. I didn't check out the callers or history of why it was that way :). - z -- 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