From patchwork Mon Apr 12 03:46:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jingbo Xu X-Patchwork-Id: 419696 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, UNPARSEABLE_RELAY, 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 7E815C433ED for ; Mon, 12 Apr 2021 03:46:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3EEA261209 for ; Mon, 12 Apr 2021 03:46:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235366AbhDLDqo (ORCPT ); Sun, 11 Apr 2021 23:46:44 -0400 Received: from out30-133.freemail.mail.aliyun.com ([115.124.30.133]:50803 "EHLO out30-133.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235261AbhDLDqo (ORCPT ); Sun, 11 Apr 2021 23:46:44 -0400 X-Alimail-AntiSpam: AC=PASS; BC=-1|-1; BR=01201311R691e4; CH=green; DM=||false|; DS=||; FP=0|-1|-1|-1|0|-1|-1|-1; HT=e01e04400; MF=jefflexu@linux.alibaba.com; NM=1; PH=DS; RN=5; SR=0; TI=SMTPD_---0UVCN7Tf_1618199185; Received: from localhost(mailfrom:jefflexu@linux.alibaba.com fp:SMTPD_---0UVCN7Tf_1618199185) by smtp.aliyun-inc.com(127.0.0.1); Mon, 12 Apr 2021 11:46:25 +0800 From: Jeffle Xu To: ricardo.canuelo@collabora.com, shuah@kernel.org Cc: linux-kselftest@vger.kernel.org, Jeffle Xu , James Wang Subject: [PATCH v3] selftests/mincore: get readahead size for check_file_mmap() Date: Mon, 12 Apr 2021 11:46:22 +0800 Message-Id: <20210412034622.59737-1-jefflexu@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210403063800.56278-1-jefflexu@linux.alibaba.com> References: <20210403063800.56278-1-jefflexu@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org The readahead size used to be 2MB, thus it's reasonable to set the file size as 4MB when checking check_file_mmap(). However since commit c2e4cd57cfa1 ("block: lift setting the readahead size into the block layer"), readahead size could be as large as twice the io_opt, and thus the hardcoded file size no longer works. check_file_mmap() may report "Read-ahead pages reached the end of the file" when the readahead size actually exceeds the file size in this case. Reported-by: James Wang Signed-off-by: Jeffle Xu --- chnages since v2: - add 'Reported-by' chnages since v1: - add the test name "mincore" in the subject line - add the error message in commit message - rename @filesize to @file_size to keep a more consistent naming convention --- .../selftests/mincore/mincore_selftest.c | 57 +++++++++++++++---- 1 file changed, 47 insertions(+), 10 deletions(-) diff --git a/tools/testing/selftests/mincore/mincore_selftest.c b/tools/testing/selftests/mincore/mincore_selftest.c index 5a1e85ff5d32..3ca542934080 100644 --- a/tools/testing/selftests/mincore/mincore_selftest.c +++ b/tools/testing/selftests/mincore/mincore_selftest.c @@ -15,6 +15,11 @@ #include #include #include +#include +#include +#include +#include +#include #include "../kselftest.h" #include "../kselftest_harness.h" @@ -195,10 +200,42 @@ TEST(check_file_mmap) int fd; int i; int ra_pages = 0; + long ra_size, file_size; + struct stat stats; + dev_t devt; + unsigned int major, minor; + char devpath[32]; + + retval = stat(".", &stats); + ASSERT_EQ(0, retval) { + TH_LOG("Can't stat pwd: %s", strerror(errno)); + } + + devt = stats.st_dev; + major = major(devt); + minor = minor(devt); + snprintf(devpath, sizeof(devpath), "/dev/block/%u:%u", major, minor); + + fd = open(devpath, O_RDONLY); + ASSERT_NE(-1, fd) { + TH_LOG("Can't open underlying disk %s", strerror(errno)); + } + + retval = ioctl(fd, BLKRAGET, &ra_size); + ASSERT_EQ(0, retval) { + TH_LOG("Error ioctl with the underlying disk: %s", strerror(errno)); + } + + /* + * BLKRAGET ioctl returns the readahead size in sectors (512 bytes). + * Make file_size large enough to contain the readahead window. + */ + ra_size *= 512; + file_size = ra_size * 2; page_size = sysconf(_SC_PAGESIZE); - vec_size = FILE_SIZE / page_size; - if (FILE_SIZE % page_size) + vec_size = file_size / page_size; + if (file_size % page_size) vec_size++; vec = calloc(vec_size, sizeof(unsigned char)); @@ -213,7 +250,7 @@ TEST(check_file_mmap) strerror(errno)); } errno = 0; - retval = fallocate(fd, 0, 0, FILE_SIZE); + retval = fallocate(fd, 0, 0, file_size); ASSERT_EQ(0, retval) { TH_LOG("Error allocating space for the temporary file: %s", strerror(errno)); @@ -223,12 +260,12 @@ TEST(check_file_mmap) * Map the whole file, the pages shouldn't be fetched yet. */ errno = 0; - addr = mmap(NULL, FILE_SIZE, PROT_READ | PROT_WRITE, + addr = mmap(NULL, file_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); ASSERT_NE(MAP_FAILED, addr) { TH_LOG("mmap error: %s", strerror(errno)); } - retval = mincore(addr, FILE_SIZE, vec); + retval = mincore(addr, file_size, vec); ASSERT_EQ(0, retval); for (i = 0; i < vec_size; i++) { ASSERT_EQ(0, vec[i]) { @@ -240,14 +277,14 @@ TEST(check_file_mmap) * Touch a page in the middle of the mapping. We expect the next * few pages (the readahead window) to be populated too. */ - addr[FILE_SIZE / 2] = 1; - retval = mincore(addr, FILE_SIZE, vec); + addr[file_size / 2] = 1; + retval = mincore(addr, file_size, vec); ASSERT_EQ(0, retval); - ASSERT_EQ(1, vec[FILE_SIZE / 2 / page_size]) { + ASSERT_EQ(1, vec[file_size / 2 / page_size]) { TH_LOG("Page not found in memory after use"); } - i = FILE_SIZE / 2 / page_size + 1; + i = file_size / 2 / page_size + 1; while (i < vec_size && vec[i]) { ra_pages++; i++; @@ -271,7 +308,7 @@ TEST(check_file_mmap) } } - munmap(addr, FILE_SIZE); + munmap(addr, file_size); close(fd); free(vec); }