Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751246AbbEARsI (ORCPT ); Fri, 1 May 2015 13:48:08 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47168 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750862AbbEARsF (ORCPT ); Fri, 1 May 2015 13:48:05 -0400 From: Jeff Moyer To: Christoph Hellwig Cc: Shaohua Li , linux-kernel@vger.kernel.org, axboe@fb.com, neilb@suse.de Subject: Re: [PATCH 3/5] blk-mq: fix plugging in blk_sq_make_request References: <20150501171656.GC16920@lst.de> X-PGP-KeyID: 1F78E1B4 X-PGP-CertKey: F6FE 280D 8293 F72C 65FD 5A58 1FF8 A7CA 1F78 E1B4 X-PCLoadLetter: What the f**k does that mean? Date: Fri, 01 May 2015 13:47:56 -0400 In-Reply-To: <20150501171656.GC16920@lst.de> (Christoph Hellwig's message of "Fri, 1 May 2015 19:16:56 +0200") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 878 Lines: 28 Christoph Hellwig writes: >> - if (use_plug && !blk_queue_nomerges(q) && >> + if (likely(!is_flush_fua) && !blk_queue_nomerges(q) && > > Please don't sprinkle likely annotations for no go reason. Especially > on metadata write heavy workloads (e.g. an NFS server) it might be very > likely. I have no problem getting rid of the likely, but I was mimicing the mq case: blk_mq_make_request: if (unlikely(is_flush_fua)) { blk_mq_bio_to_request(rq, bio); blk_insert_flush(rq); goto run_queue; } So would you also want that unlikely removed? Cheers, Jeff -- 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/