Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751004AbaBKIiv (ORCPT ); Tue, 11 Feb 2014 03:38:51 -0500 Received: from mx1.redhat.com ([209.132.183.28]:22712 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750758AbaBKIiq (ORCPT ); Tue, 11 Feb 2014 03:38:46 -0500 Date: Tue, 11 Feb 2014 09:40:40 +0100 From: Alexander Gordeev To: Tejun Heo Cc: linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org, "Nicholas A. Bellinger" Subject: Re: [PATCH 1/1] libata: Get rid of ata_port::qc_allocated bitmask Message-ID: <20140211084039.GC16680@dhcp-26-207.brq.redhat.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 21, 2014 at 04:02:26PM +0100, Alexander Gordeev wrote: > Scanning ata_port::qc_allocated bitmask for free tags has > been a performance bottleneck due to the cache line bouncing. > This update replaces ata_port::qc_allocated bitmask with > optimized for parallel access percpu_ida tags allocator. Hi Tejun, There is a discussion about imperfect percpu_ida handling of low nr of tags. I think this change is too early to bring. Thanks! -- Regards, Alexander Gordeev agordeev@redhat.com -- 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/