Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754472Ab1DLTPm (ORCPT ); Tue, 12 Apr 2011 15:15:42 -0400 Received: from mail-vx0-f174.google.com ([209.85.220.174]:39126 "EHLO mail-vx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751317Ab1DLTPl (ORCPT ); Tue, 12 Apr 2011 15:15:41 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=iy6OCOGj6FuDh+PuoFrkN2xCRBg73g1ToNMwFu9p7+qVtCkjeADuG//iLabLIr9ZoU LRDiFWmh36gLyeirat56IhLJXtOZsc6ITxkbVgajVillhpV7DfM44VUyqskWhPdJt0MQ wfYdhpDMAI3ElhwkFjzRiIiO5Ppw4BVWUtrd8= Date: Wed, 13 Apr 2011 04:15:34 +0900 From: Tejun Heo To: Shaohua Li Cc: lkml , Andrew Morton , cl@linux.com Subject: Re: [PATCH 4/4]percpu_counter: use atomic64 for counter Message-ID: <20110412191534.GE16342@mtj.dyndns.org> References: <1302595446.3981.130.camel@sli10-conroe> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1302595446.3981.130.camel@sli10-conroe> 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: 911 Lines: 25 Hello, On Tue, Apr 12, 2011 at 04:04:06PM +0800, Shaohua Li wrote: > should tunning the batch count, but if we can make percpu_counter better, why > not? First of all, the lock being only in slow paths, it's quite unlikely to get ever contended. Also, because the lock duration is always extremely short, conversion to atomic_t isn't too likely to gain anything significant, especially in cold paths. That said, if it's all gains, why not? I don't know. Maybe. Given problems in the previous patches, I don't feel too enthusiastic for this series at this point but I'm quite sleep deprived now so it might just be me not the patch itself. Thanks. -- tejun -- 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/