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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3BF51C433F5 for ; Mon, 25 Apr 2022 20:18:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237389AbiDYUVm (ORCPT ); Mon, 25 Apr 2022 16:21:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56436 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239808AbiDYUVm (ORCPT ); Mon, 25 Apr 2022 16:21:42 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 951F93134E for ; Mon, 25 Apr 2022 13:18:37 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 30EB860F01 for ; Mon, 25 Apr 2022 20:18:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 84392C385A4; Mon, 25 Apr 2022 20:18:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1650917916; bh=l7Jy3CB5aFORS3VXaJDWqafAVdvrywIWTNiHetb8Rl8=; h=Date:To:From:Subject:From; b=vf7NXw4SLniwVtv5WrxfLRluBPUyVlFNJOSQFOVms3NQcJfsuCP5HwinE+lVUaGl1 1FQDO/rlgNtjdgft0ENxHwVnXhaxFACwtTBqng586msPcZo081UPu5u/zgZezDdLYk RkHm/WozsPY7UXv7dBklTeEwElup7lxrTvxREmG8= Date: Mon, 25 Apr 2022 13:18:35 -0700 To: mm-commits@vger.kernel.org, yuzhao@google.com, weixugc@google.com, vaibhav@linux.ibm.com, tj@kernel.org, tim.c.chen@linux.intel.com, shuah@kernel.org, shakeelb@google.com, roman.gushchin@linux.dev, rientjes@google.com, mkoutny@suse.com, mhocko@suse.com, lizefan.x@bytedance.com, hannes@cmpxchg.org, gthelen@google.com, dave.hansen@linux.intel.com, corbet@lwn.net, chenwandun@huawei.com, yosryahmed@google.com, akpm@linux-foundation.org From: Andrew Morton Subject: + selftests-cgroup-return-errno-from-cg_read-cg_write-on-failure.patch added to -mm tree Message-Id: <20220425201836.84392C385A4@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: selftests: cgroup: return -errno from cg_read()/cg_write() on failure has been added to the -mm tree. Its filename is selftests-cgroup-return-errno-from-cg_read-cg_write-on-failure.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/selftests-cgroup-return-errno-from-cg_read-cg_write-on-failure.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/selftests-cgroup-return-errno-from-cg_read-cg_write-on-failure.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Yosry Ahmed Subject: selftests: cgroup: return -errno from cg_read()/cg_write() on failure Currently, cg_read()/cg_write() returns 0 on success and -1 on failure. Modify them to return the -errno on failure. Link: https://lkml.kernel.org/r/20220425190040.2475377-3-yosryahmed@google.com Signed-off-by: Yosry Ahmed Acked-by: Shakeel Butt Acked-by: David Rientjes Cc: Chen Wandun Cc: Dave Hansen Cc: Greg Thelen Cc: Johannes Weiner Cc: Jonathan Corbet Cc: Michal Hocko Cc: "Michal Koutn" Cc: Roman Gushchin Cc: Shuah Khan Cc: Tejun Heo Cc: Tim Chen Cc: Vaibhav Jain Cc: Wei Xu Cc: Yu Zhao Cc: Zefan Li Signed-off-by: Andrew Morton --- tools/testing/selftests/cgroup/cgroup_util.c | 44 +++++++---------- 1 file changed, 19 insertions(+), 25 deletions(-) --- a/tools/testing/selftests/cgroup/cgroup_util.c~selftests-cgroup-return-errno-from-cg_read-cg_write-on-failure +++ a/tools/testing/selftests/cgroup/cgroup_util.c @@ -19,6 +19,7 @@ #include "cgroup_util.h" #include "../clone3/clone3_selftests.h" +/* Returns read len on success, or -errno on failure. */ static ssize_t read_text(const char *path, char *buf, size_t max_len) { ssize_t len; @@ -26,35 +27,29 @@ static ssize_t read_text(const char *pat fd = open(path, O_RDONLY); if (fd < 0) - return fd; + return -errno; len = read(fd, buf, max_len - 1); - if (len < 0) - goto out; - buf[len] = 0; -out: + if (len >= 0) + buf[len] = 0; + close(fd); - return len; + return len < 0 ? -errno : len; } +/* Returns written len on success, or -errno on failure. */ static ssize_t write_text(const char *path, char *buf, ssize_t len) { int fd; fd = open(path, O_WRONLY | O_APPEND); if (fd < 0) - return fd; + return -errno; len = write(fd, buf, len); - if (len < 0) { - close(fd); - return len; - } - close(fd); - - return len; + return len < 0 ? -errno : len; } char *cg_name(const char *root, const char *name) @@ -87,16 +82,16 @@ char *cg_control(const char *cgroup, con return ret; } +/* Returns 0 on success, or -errno on failure. */ int cg_read(const char *cgroup, const char *control, char *buf, size_t len) { char path[PATH_MAX]; + ssize_t ret; snprintf(path, sizeof(path), "%s/%s", cgroup, control); - if (read_text(path, buf, len) >= 0) - return 0; - - return -1; + ret = read_text(path, buf, len); + return ret >= 0 ? 0 : ret; } int cg_read_strcmp(const char *cgroup, const char *control, @@ -177,17 +172,15 @@ long cg_read_lc(const char *cgroup, cons return cnt; } +/* Returns 0 on success, or -errno on failure. */ int cg_write(const char *cgroup, const char *control, char *buf) { char path[PATH_MAX]; - ssize_t len = strlen(buf); + ssize_t len = strlen(buf), ret; snprintf(path, sizeof(path), "%s/%s", cgroup, control); - - if (write_text(path, buf, len) == len) - return 0; - - return -1; + ret = write_text(path, buf, len); + return ret == len ? 0 : ret; } int cg_find_unified_root(char *root, size_t len) @@ -557,7 +550,8 @@ ssize_t proc_read_text(int pid, bool thr else snprintf(path, sizeof(path), "/proc/%d/%s", pid, item); - return read_text(path, buf, size); + size = read_text(path, buf, size); + return size < 0 ? -1 : size; } int proc_read_strstr(int pid, bool thread, const char *item, const char *needle) _ Patches currently in -mm which might be from yosryahmed@google.com are selftests-cgroup-return-errno-from-cg_read-cg_write-on-failure.patch selftests-cgroup-fix-alloc_anon_noexit-instantly-freeing-memory.patch selftests-cgroup-add-a-selftest-for-memoryreclaim.patch