From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8AD75C43441 for ; Thu, 22 Nov 2018 10:22:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4E9C721104 for ; Thu, 22 Nov 2018 10:22:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="E8N1I8nA" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4E9C721104 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2405298AbeKVVBX (ORCPT ); Thu, 22 Nov 2018 16:01:23 -0500 Received: from mail.kernel.org ([198.145.29.99]:55252 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2405283AbeKVVBX (ORCPT ); Thu, 22 Nov 2018 16:01:23 -0500 Received: from localhost (unknown [95.99.132.93]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E237320684; Thu, 22 Nov 2018 10:22:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1542882155; bh=z7AGX3R207QN9rszFYIZXQje4VZbYRok3hW/+QUAMa8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=E8N1I8nArpzm387Zw3RDqQBYUa8+a2dREw41WjQ+gEPUdsJ3mYTz6mHxoapoPvHbq t1kpRWql1S+QaoDVNNDRoF2Odmq5f2KpEfayuelGa7ZRzd+jHuY+a+H8bLCoxMfLAw ox5oJ0pV7X5hJt26/T0oTzTkxD7GvtC0G25e0hUQ= Date: Thu, 22 Nov 2018 11:22:31 +0100 From: Greg Kroah-Hartman To: Gao Xiang Cc: devel@driverdev.osuosl.org, linux-erofs@lists.ozlabs.org, Chao Yu , LKML , weidu.du@huawei.com, Miao Xie Subject: Re: [PATCH 05/10] staging: erofs: add a full barrier in erofs_workgroup_unfreeze Message-ID: <20181122102230.GF3189@kroah.com> References: <20181120143425.43637-1-gaoxiang25@huawei.com> <20181120143425.43637-6-gaoxiang25@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181120143425.43637-6-gaoxiang25@huawei.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 20, 2018 at 10:34:20PM +0800, Gao Xiang wrote: > Just like other generic locks, insert a full barrier > in case of memory reorder. > > Reviewed-by: Chao Yu > Signed-off-by: Gao Xiang > --- > drivers/staging/erofs/internal.h | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/staging/erofs/internal.h b/drivers/staging/erofs/internal.h > index 2e0ef92c138b..f77653d33633 100644 > --- a/drivers/staging/erofs/internal.h > +++ b/drivers/staging/erofs/internal.h > @@ -209,6 +209,7 @@ static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp, > static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp, > int orig_val) > { > + smp_mb(); Please document this memory barrier. It does not make much sense to me... thanks, greg k-h