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 CF9E5C61DA4 for ; Wed, 22 Feb 2023 14:48:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232316AbjBVOsA (ORCPT ); Wed, 22 Feb 2023 09:48:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59326 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232201AbjBVOrh (ORCPT ); Wed, 22 Feb 2023 09:47:37 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8249F38EB6 for ; Wed, 22 Feb 2023 06:47:21 -0800 (PST) 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 ams.source.kernel.org (Postfix) with ESMTPS id BC6C2B815C9 for ; Wed, 22 Feb 2023 14:47:18 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 60642C4339E; Wed, 22 Feb 2023 14:47:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1677077237; bh=3ds3/cTbh0yU84XZ4nwDnOjFVf7ivtfK68suy9ql4Kw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=O/SXFOf0UVWM/2lQuF9pRCQJD7/Qjp1ltLC72UF7I04QPqLkTNXiYIUbh83lE8D6P qI/1/V3Rz/i9ea+1Q7TIPhxLJC0epNbZysQD2oisZBi73sQYcCq8mBgRma8Mv4S8KI 79IkEWklYyfvR/pp5se81yl7XOoFJZ50LTqpYdgtEHNd4klwuarw0kxpeDfNnr3zmJ LqBU2SnACBrx2yZ5SKNg3m9UjybeHnfUTlc8GatJcYbBnJE3YsVNSgvPMSJLS7FHg/ M9dIgk/6Kf7kqCTGT7u45sBjDL//mMflCmQpOjNH+k/XnbdQf2cyCbbY1Jg6OGcI9E FF1NHlqN4bxfw== From: Frederic Weisbecker To: Thomas Gleixner Cc: LKML , Frederic Weisbecker , Alexey Dobriyan , Wei Li , Peter Zijlstra , Mirsad Goran Todorovac , Yu Liao , Hillf Danton , Ingo Molnar Subject: [PATCH 8/8] selftests/proc: Assert clock_gettime(CLOCK_BOOTTIME) VS /proc/uptime monotonicity Date: Wed, 22 Feb 2023 15:46:49 +0100 Message-Id: <20230222144649.624380-9-frederic@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230222144649.624380-1-frederic@kernel.org> References: <20230222144649.624380-1-frederic@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The first field of /proc/uptime relies on the CLOCK_BOOTTIME clock which can also be fetched from clock_gettime() API. Improve the test coverage while verifying the monotonicity of CLOCK_BOOTTIME accross both interfaces. Suggested-by: Thomas Gleixner Cc: Yu Liao Cc: Hillf Danton Cc: Ingo Molnar Cc: Wei Li Cc: Alexey Dobriyan Cc: Mirsad Goran Todorovac Cc: Peter Zijlstra Signed-off-by: Frederic Weisbecker --- .../testing/selftests/proc/proc-uptime-001.c | 21 ++++++++++++++---- .../testing/selftests/proc/proc-uptime-002.c | 22 +++++++++++++++---- tools/testing/selftests/proc/proc-uptime.h | 12 ++++++++++ 3 files changed, 47 insertions(+), 8 deletions(-) diff --git a/tools/testing/selftests/proc/proc-uptime-001.c b/tools/testing/selftests/proc/proc-uptime-001.c index 35bddd9dd60b..f335eec5067e 100644 --- a/tools/testing/selftests/proc/proc-uptime-001.c +++ b/tools/testing/selftests/proc/proc-uptime-001.c @@ -13,9 +13,9 @@ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ -// Test that boottime value in /proc/uptime increments monotonically. -// We don't test idle time monotonicity due to broken iowait task -// counting, cf: comment above get_cpu_idle_time_us() +// Test that boottime value in /proc/uptime and CLOCK_BOOTTIME increment +// monotonically. We don't test idle time monotonicity due to broken iowait +// task counting, cf: comment above get_cpu_idle_time_us() #undef NDEBUG #include #include @@ -27,7 +27,7 @@ int main(void) { - uint64_t start, u0, u1; + uint64_t start, u0, u1, c0, c1; int fd; fd = open("/proc/uptime", O_RDONLY); @@ -35,10 +35,23 @@ int main(void) u0 = proc_uptime(fd); start = u0; + c0 = clock_boottime(); + do { u1 = proc_uptime(fd); + c1 = clock_boottime(); + + /* Is /proc/uptime monotonic ? */ assert(u1 >= u0); + + /* Is CLOCK_BOOTTIME monotonic ? */ + assert(c1 >= c0); + + /* Is CLOCK_BOOTTIME VS /proc/uptime monotonic ? */ + assert(c0 >= u0); + u0 = u1; + c0 = c1; } while (u1 - start < 100); return 0; diff --git a/tools/testing/selftests/proc/proc-uptime-002.c b/tools/testing/selftests/proc/proc-uptime-002.c index 7ad79d5eaa84..ae453daa96c1 100644 --- a/tools/testing/selftests/proc/proc-uptime-002.c +++ b/tools/testing/selftests/proc/proc-uptime-002.c @@ -13,9 +13,10 @@ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ -// Test that boottime value in /proc/uptime increments monotonically -// while shifting across CPUs. We don't test idle time monotonicity -// due to broken iowait task counting, cf: comment above get_cpu_idle_time_us() +// Test that boottime value in /proc/uptime and CLOCK_BOOTTIME increment +// monotonically while shifting across CPUs. We don't test idle time +// monotonicity due to broken iowait task counting, cf: comment above +// get_cpu_idle_time_us() #undef NDEBUG #include #include @@ -43,10 +44,10 @@ static inline int sys_sched_setaffinity(pid_t pid, unsigned int len, unsigned lo int main(void) { + uint64_t u0, u1, c0, c1; unsigned int len; unsigned long *m; unsigned int cpu; - uint64_t u0, u1; int fd; /* find out "nr_cpu_ids" */ @@ -62,6 +63,8 @@ int main(void) assert(fd >= 0); u0 = proc_uptime(fd); + c0 = clock_boottime(); + for (cpu = 0; cpu < len * 8; cpu++) { memset(m, 0, len); m[cpu / (8 * sizeof(unsigned long))] |= 1UL << (cpu % (8 * sizeof(unsigned long))); @@ -70,8 +73,19 @@ int main(void) sys_sched_setaffinity(0, len, m); u1 = proc_uptime(fd); + c1 = clock_boottime(); + + /* Is /proc/uptime monotonic ? */ assert(u1 >= u0); + + /* Is CLOCK_BOOTTIME monotonic ? */ + assert(c1 >= c0); + + /* Is CLOCK_BOOTTIME VS /proc/uptime monotonic ? */ + assert(c0 >= u0); + u0 = u1; + c0 = c1; } return 0; diff --git a/tools/testing/selftests/proc/proc-uptime.h b/tools/testing/selftests/proc/proc-uptime.h index ca55abeb0ccc..730cce4a3d73 100644 --- a/tools/testing/selftests/proc/proc-uptime.h +++ b/tools/testing/selftests/proc/proc-uptime.h @@ -19,9 +19,21 @@ #include #include #include +#include #include "proc.h" +static uint64_t clock_boottime(void) +{ + struct timespec ts; + int err; + + err = clock_gettime(CLOCK_BOOTTIME, &ts); + assert(err >= 0); + + return (ts.tv_sec * 100) + (ts.tv_nsec / 10000000); +} + static uint64_t proc_uptime(int fd) { uint64_t val1, val2; -- 2.34.1