From patchwork Fri Feb 26 14:00:11 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthew Wilcox X-Patchwork-Id: 12106737 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=-16.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 C2041C433E0 for ; Fri, 26 Feb 2021 14:21:25 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 5109964DE3 for ; Fri, 26 Feb 2021 14:21:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5109964DE3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 9D84D6B006C; Fri, 26 Feb 2021 09:21:24 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 989166B006E; Fri, 26 Feb 2021 09:21:24 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8779C6B0070; Fri, 26 Feb 2021 09:21:24 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0234.hostedemail.com [216.40.44.234]) by kanga.kvack.org (Postfix) with ESMTP id 6DAF56B006C for ; Fri, 26 Feb 2021 09:21:24 -0500 (EST) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 2EC458248D7C for ; Fri, 26 Feb 2021 14:21:24 +0000 (UTC) X-FDA: 77860631688.05.D1D9648 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf04.hostedemail.com (Postfix) with ESMTP id 3E54FFF for ; Fri, 26 Feb 2021 14:21:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type:Content-ID: Content-Description:In-Reply-To:References; bh=mEMVgXDc2/lvAr/oSwoM2Grls7q5GWAhife7U4SoQCs=; b=wFihlEPtOvO4y5n1FoFi518OpR kH+nmDloDHB7bz2+rEFYGRKemxQgetpC4moY3yM7ZGNjxUMpJYstADZpE4fOWQmUINRxrNk58+Fe3 Fo1YDs9T7FMZBAXCioGOC/WY1EDc6IA910BJkkbWKy3uj2Xt3cNlSj2oyaJKyIqzkPi4hcHU0F3tM aOLu1uOSjqAsbXs9144pbyN7n5wPXG/l3etE3N/PZiHeUW+4vFHzkRn5g9u13d+YU5WUKHQZTTORd XjBrG1WJR0NuwZMfuwMhEFSLd6e4Js6v8PlX+4pAE4FXaR5CdopODwM6ldwe7aQ7FN2Pk+ZwLGJLH fWnKCkIQ==; Received: from willy by casper.infradead.org with local (Exim 4.94 #2 (Red Hat Linux)) id 1lFdfM-00C6F4-AD; Fri, 26 Feb 2021 14:00:24 +0000 From: "Matthew Wilcox (Oracle)" To: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, Kent Overstreet , Christoph Hellwig , Andrew Morton Cc: "Matthew Wilcox (Oracle)" Subject: [PATCH] mm/filemap: Use filemap_read_page in filemap_fault Date: Fri, 26 Feb 2021 14:00:11 +0000 Message-Id: <20210226140011.2883498-1-willy@infradead.org> X-Mailer: git-send-email 2.29.2 MIME-Version: 1.0 X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 3E54FFF X-Stat-Signature: fupnojm8t81d5jwpir9mhawbyti1hhsq Received-SPF: none (infradead.org>: No applicable sender policy available) receiver=imf04; identity=mailfrom; envelope-from=""; helo=casper.infradead.org; client-ip=90.155.50.34 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1614349281-414348 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: After splitting generic_file_buffered_read() into smaller parts, it turns out we can reuse one of the parts in filemap_fault(). This fixes an oversight -- waiting for the I/O to complete is now interruptible by a fatal signal. And it saves us a few bytes of text in an unlikely path. $ ./scripts/bloat-o-meter before.o after.o add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-207 (-207) Function old new delta filemap_fault 2187 1980 -207 Total: Before=37491, After=37284, chg -0.55% Signed-off-by: Matthew Wilcox (Oracle) --- mm/filemap.c | 10 +--------- 1 file changed, 1 insertion(+), 9 deletions(-) diff --git a/mm/filemap.c b/mm/filemap.c index 46a8b9e82434..f7ab86d13692 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2748,7 +2748,6 @@ vm_fault_t filemap_fault(struct vm_fault *vmf) struct file *file = vmf->vma->vm_file; struct file *fpin = NULL; struct address_space *mapping = file->f_mapping; - struct file_ra_state *ra = &file->f_ra; struct inode *inode = mapping->host; pgoff_t offset = vmf->pgoff; pgoff_t max_off; @@ -2835,14 +2834,8 @@ vm_fault_t filemap_fault(struct vm_fault *vmf) * because there really aren't any performance issues here * and we need to check for errors. */ - ClearPageError(page); fpin = maybe_unlock_mmap_for_io(vmf, fpin); - error = mapping->a_ops->readpage(file, page); - if (!error) { - wait_on_page_locked(page); - if (!PageUptodate(page)) - error = -EIO; - } + error = filemap_read_page(file, mapping, page); if (fpin) goto out_retry; put_page(page); @@ -2850,7 +2843,6 @@ vm_fault_t filemap_fault(struct vm_fault *vmf) if (!error || error == AOP_TRUNCATED_PAGE) goto retry_find; - shrink_readahead_size_eio(ra); return VM_FAULT_SIGBUS; out_retry: