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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C467DC021BE for ; Thu, 27 Feb 2025 13:19:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=3D27/czJ9tTae692WszgtvNJJBNH99Ngz/ZrVGIZii8=; b=P6Xxf1r7cMxLvCGAffAYHmdom+ J06DJbPgFtBTU9TiAb2gnTPZtUnCgcMmSj/+cT1zQ6XNjYIVzdh8s3V9LasKIM9I64b3gdX2QfLWH W/pL2bmdqFn7ifJRo4Ir09YxArYH0yCZ6RKVySJqNsE/iRTWjiRIlgaxFu4r0QwFaALQkdWmMAaeT YQpZpNMCDYGZuHXiJTg7PyuTyz7SgI8xHln2M7O2JLCWcn7mIP4erb0Xls7hN0Y7hyssesgkxZOxE PsxWLH7O03y45APgO2rz15qvmaX8E0oSCsLIZtSV+E1Ez2X3CKLCRQiV6fUT3aDho/yCVUZoiFC4o cuTLHOFQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tndnA-00000007UrZ-1PYK; Thu, 27 Feb 2025 13:19:08 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tnd31-00000007NKt-2Hjs for linux-arm-kernel@lists.infradead.org; Thu, 27 Feb 2025 12:31:28 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id D54B25C28D8; Thu, 27 Feb 2025 12:30:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3D25AC4CEE9; Thu, 27 Feb 2025 12:31:20 +0000 (UTC) Date: Thu, 27 Feb 2025 12:31:17 +0000 From: Catalin Marinas To: Shuai Xue Cc: yazen.ghannam@amd.com, mark.rutland@arm.com, mingo@redhat.com, robin.murphy@arm.com, Jonathan.Cameron@huawei.com, bp@alien8.de, rafael@kernel.org, linux-arm-kernel@lists.infradead.org, wangkefeng.wang@huawei.com, tanxiaofei@huawei.com, mawupeng1@huawei.com, tony.luck@intel.com, linmiaohe@huawei.com, naoya.horiguchi@nec.com, james.morse@arm.com, tongtiangen@huawei.com, gregkh@linuxfoundation.org, will@kernel.org, jarkko@kernel.org, linux-acpi@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, linux-edac@vger.kernel.org, x86@kernel.org, justin.he@arm.com, ardb@kernel.org, ying.huang@linux.alibaba.com, ashish.kalra@amd.com, baolin.wang@linux.alibaba.com, tglx@linutronix.de, dave.hansen@linux.intel.com, lenb@kernel.org, hpa@zytor.com, robert.moore@intel.com, lvying6@huawei.com, xiexiuqi@huawei.com, zhuo.song@linux.alibaba.com Subject: Re: [PATCH v18 2/3] mm: memory-failure: move return value documentation to function declaration Message-ID: References: <20250107081735.16159-1-xueshuai@linux.alibaba.com> <20250107081735.16159-3-xueshuai@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250107081735.16159-3-xueshuai@linux.alibaba.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250227_043127_671442_54261632 X-CRM114-Status: GOOD ( 18.55 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org (going through patches in my inbox) On Tue, Jan 07, 2025 at 04:17:34PM +0800, Shuai Xue wrote: > Part of return value comments for memory_failure() were originally > documented at the call site. Move those comments to the function > declaration to improve code readability and to provide developers with s/declaration/definition/ > immediate access to function usage and return information. > > Signed-off-by: Shuai Xue > Reviewed-by: Jarkko Sakkinen > Reviewed-by: Jonathan Cameron > Reviewed-by: Yazen Ghannam > Reviewed-by: Jane Chu > --- > arch/x86/kernel/cpu/mce/core.c | 7 ------- > mm/memory-failure.c | 10 +++++++--- > 2 files changed, 7 insertions(+), 10 deletions(-) > > diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c > index 7fb5556a0b53..d1dd7f892514 100644 > --- a/arch/x86/kernel/cpu/mce/core.c > +++ b/arch/x86/kernel/cpu/mce/core.c > @@ -1398,13 +1398,6 @@ static void kill_me_maybe(struct callback_head *cb) > return; > } > > - /* > - * -EHWPOISON from memory_failure() means that it already sent SIGBUS > - * to the current process with the proper error info, > - * -EOPNOTSUPP means hwpoison_filter() filtered the error event, > - * > - * In both cases, no further processing is required. > - */ > if (ret == -EHWPOISON || ret == -EOPNOTSUPP) > return; > > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index a7b8ccd29b6f..14c316d7d38d 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -2211,9 +2211,13 @@ static void kill_procs_now(struct page *p, unsigned long pfn, int flags, > * Must run in process context (e.g. a work queue) with interrupts > * enabled and no spinlocks held. > * > - * Return: 0 for successfully handled the memory error, > - * -EOPNOTSUPP for hwpoison_filter() filtered the error event, > - * < 0(except -EOPNOTSUPP) on failure. > + * Return: > + * 0 - success, > + * -ENXIO - memory not managed by the kernel > + * -EOPNOTSUPP - hwpoison_filter() filtered the error event, > + * -EHWPOISON - the page was already poisoned, potentially > + * kill process, > + * other negative values - failure. > */ > int memory_failure(unsigned long pfn, int flags) > { Why not keep the comment in both places? One is about the x86 decisions, the other is about what memory_failure() can return. -- Catalin