Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932552Ab0KRRWY (ORCPT ); Thu, 18 Nov 2010 12:22:24 -0500 Received: from mail-qy0-f174.google.com ([209.85.216.174]:46504 "EHLO mail-qy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755241Ab0KRRWX (ORCPT ); Thu, 18 Nov 2010 12:22:23 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:from:date :x-google-sender-auth:message-id:subject:to:cc:content-type; b=uoCsGa0hvqvVsg1r24P0SNYNRfne2bsr00Qpcms60Xv/naUlfhY+E1mj8ovnyDfuxF Jw5tDpfQnygFn32TFKbx//ckQSf6Uq4rpplNuCkSizC8/hAmDu4xfR1za16HJQqDjguW T+q+qVYRhEYdswtAK6UwFljK2Eqj9QiCAAmDg= MIME-Version: 1.0 In-Reply-To: <1290094063.3187.41.camel@heimdal.trondhjem.org> References: <1290094063.3187.41.camel@heimdal.trondhjem.org> From: Peng Tao Date: Fri, 19 Nov 2010 01:22:01 +0800 X-Google-Sender-Auth: 1FjSIzTpduqr0CYoRu-9OzUpqjE Message-ID: Subject: Re: Question about nfs_page_async_flush assertion To: Trond Myklebust Cc: linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 941 Lines: 24 On Thu, Nov 18, 2010 at 11:27 PM, Trond Myklebust wrote: > On Thu, 2010-11-18 at 18:53 +0800, Peng Tao wrote: >> Hi, all, >> >> nfs_writepages calls into >> write_cache_pages()->nfs_writepages_callback()->nfs_do_writepage()->nfs_page_async_flush(), >> where it asserts BUG_ON(test_bit(PG_CLEAN, &req->wb_flags)). >> My question is: how do we guarantee the request has PG_CLEAN flag set? > > We don't. We guarantee that the request has PG_CLEAN cleared, and that > is done when we dirty the page (see nfs_try_to_update_request()). Ah, I missed. It is test_bit() other than !test_bit(). Thank you Trond for pointing it out. Sorry for the spam :) -- Thanks, -Bergwolf -- 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/