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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 776A8C433DB for ; Wed, 24 Feb 2021 20:05:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3A27A64F1F for ; Wed, 24 Feb 2021 20:05:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234917AbhBXUFA (ORCPT ); Wed, 24 Feb 2021 15:05:00 -0500 Received: from mail.kernel.org ([198.145.29.99]:55484 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235406AbhBXUDH (ORCPT ); Wed, 24 Feb 2021 15:03:07 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id D7CE164EC3; Wed, 24 Feb 2021 20:02:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1614196956; bh=IZFR+1MgXfbwAerHWVzCbYbdrlC2nLdj5MY1wrhuZhQ=; h=Date:From:To:Subject:In-Reply-To:From; b=UmpHEu8GFFXroVVuozOB6qTgKj8aof9L5snAEEGJGj/Pq/rR5nrsqQ3YTdN0Y6Taj ccqKd7eLj8MiKb5Ttwca0HqiCsKyfYVWUBQpzH1w0KJxQOFdV9eBa+rLPFlmOmNNlO ZinVEnrpZSHNp9i4/10/ZrzYUHkNWpz8UnnuScPY= Date: Wed, 24 Feb 2021 12:02:35 -0800 From: Andrew Morton To: akpm@linux-foundation.org, hch@lst.de, kent.overstreet@gmail.com, linmiaohe@huawei.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org, willy@infradead.org Subject: [patch 044/173] mm/filemap: restructure filemap_get_pages Message-ID: <20210224200235.QaAy8bCLA%akpm@linux-foundation.org> In-Reply-To: <20210224115824.1e289a6895087f10c41dd8d6@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: "Matthew Wilcox (Oracle)" Subject: mm/filemap: restructure filemap_get_pages Remove the got_pages label, remove indentation, rename find_page to retry, simplify error handling. Link: https://lkml.kernel.org/r/20210122160140.223228-16-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Kent Overstreet Reviewed-by: Christoph Hellwig Cc: Miaohe Lin Signed-off-by: Andrew Morton --- mm/filemap.c | 71 +++++++++++++++++++------------------------------ 1 file changed, 28 insertions(+), 43 deletions(-) --- a/mm/filemap.c~mm-filemap-restructure-filemap_get_pages +++ a/mm/filemap.c @@ -2349,70 +2349,55 @@ static int filemap_get_pages(struct kioc struct file_ra_state *ra = &filp->f_ra; pgoff_t index = iocb->ki_pos >> PAGE_SHIFT; pgoff_t last_index; + struct page *page; int err = 0; last_index = DIV_ROUND_UP(iocb->ki_pos + iter->count, PAGE_SIZE); -find_page: +retry: if (fatal_signal_pending(current)) return -EINTR; filemap_get_read_batch(mapping, index, last_index, pvec); - if (pvec->nr) - goto got_pages; - - if (iocb->ki_flags & IOCB_NOIO) - return -EAGAIN; - - page_cache_sync_readahead(mapping, ra, filp, index, last_index - index); - - filemap_get_read_batch(mapping, index, last_index, pvec); + if (!pagevec_count(pvec)) { + if (iocb->ki_flags & IOCB_NOIO) + return -EAGAIN; + page_cache_sync_readahead(mapping, ra, filp, index, + last_index - index); + filemap_get_read_batch(mapping, index, last_index, pvec); + } if (!pagevec_count(pvec)) { if (iocb->ki_flags & (IOCB_NOWAIT | IOCB_WAITQ)) return -EAGAIN; err = filemap_create_page(filp, mapping, iocb->ki_pos >> PAGE_SHIFT, pvec); if (err == AOP_TRUNCATED_PAGE) - goto find_page; + goto retry; return err; } -got_pages: - { - struct page *page = pvec->pages[pvec->nr - 1]; - - if (PageReadahead(page)) { - err = filemap_readahead(iocb, filp, mapping, page, - last_index); - if (err) { - put_page(page); - pvec->nr--; - goto err; - } - } - if (!PageUptodate(page)) { - if ((iocb->ki_flags & IOCB_WAITQ) && - pagevec_count(pvec) > 1) - iocb->ki_flags |= IOCB_NOWAIT; - err = filemap_update_page(iocb, mapping, iter, page); - if (err) { - if (err < 0) - put_page(page); - pvec->nr--; - } - } + page = pvec->pages[pagevec_count(pvec) - 1]; + if (PageReadahead(page)) { + err = filemap_readahead(iocb, filp, mapping, page, last_index); + if (err) + goto err; + } + if (!PageUptodate(page)) { + if ((iocb->ki_flags & IOCB_WAITQ) && pagevec_count(pvec) > 1) + iocb->ki_flags |= IOCB_NOWAIT; + err = filemap_update_page(iocb, mapping, iter, page); + if (err) + goto err; } + return 0; err: - if (likely(pvec->nr)) + if (err < 0) + put_page(page); + if (likely(--pvec->nr)) return 0; if (err == AOP_TRUNCATED_PAGE) - goto find_page; - if (err) - return err; - /* - * No pages and no error means we raced and should retry: - */ - goto find_page; + goto retry; + return err; } /** _