From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from foss.arm.com ([217.140.110.172]:42400 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731965AbfFMPWx (ORCPT ); Thu, 13 Jun 2019 11:22:53 -0400 Subject: Re: [PATCH v4 3/3] kselftest: Extend vDSO selftest to clock_getres From: Vincenzo Frascino References: <20190523112116.19233-1-vincenzo.frascino@arm.com> <20190523112116.19233-4-vincenzo.frascino@arm.com> <87lfyrp0d2.fsf@concordia.ellerman.id.au> Message-ID: <5262a024-7af1-4792-ec74-4cb5f2b0e76c@arm.com> Date: Thu, 13 Jun 2019 16:22:49 +0100 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-s390-owner@vger.kernel.org List-ID: To: Michael Ellerman , linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: Christophe Leroy , Benjamin Herrenschmidt , Paul Mackerras , Martin Schwidefsky , Heiko Carstens , Shuah Khan , Thomas Gleixner , Arnd Bergmann Hi Michael, I wanted to check with you if you had time to have a look at my new version (v5) of the patches with the fixed test, and if they are ready to be merged or if there is anything else I can do. Thanks and Regards, Vincenzo On 28/05/2019 12:57, Vincenzo Frascino wrote: > Hi Michael, > > thank you for your reply. > > On 28/05/2019 07:19, Michael Ellerman wrote: >> Vincenzo Frascino writes: >> >>> The current version of the multiarch vDSO selftest verifies only >>> gettimeofday. >>> >>> Extend the vDSO selftest to clock_getres, to verify that the >>> syscall and the vDSO library function return the same information. >>> >>> The extension has been used to verify the hrtimer_resoltion fix. >> >> This is passing for me even without patch 1 applied, shouldn't it fail >> without the fix? What am I missing? >> > > This is correct, because during the refactoring process I missed an "n" :) > > if·((x.tv_sec·!=·y.tv_sec)·||·(x.tv_sec·!=·y.tv_sec)) > > Should be: > > if·((x.tv_sec·!=·y.tv_sec)·||·(x.tv_nsec·!=·y.tv_nsec)) > > My mistake, I am going to fix the test and re-post v5 of this set. > > Without my patch if you pass "highres=off" to the kernel (as a command line > parameter) it leads to a broken implementation of clock_getres since the value > of CLOCK_REALTIME_RES does not change at runtime. > > Expected result (with highres=off): > > # uname -r > 5.2.0-rc2 > # ./vdso_clock_getres > clock_id: CLOCK_REALTIME [FAIL] > clock_id: CLOCK_BOOTTIME [PASS] > clock_id: CLOCK_TAI [PASS] > clock_id: CLOCK_REALTIME_COARSE [PASS] > clock_id: CLOCK_MONOTONIC [FAIL] > clock_id: CLOCK_MONOTONIC_RAW [PASS] > clock_id: CLOCK_MONOTONIC_COARSE [PASS] > > The reason of this behavior is that the only clocks supported by getres on > powerpc are CLOCK_REALTIME and CLOCK_MONOTONIC, the rest on the clocks use > always syscalls. > >> # uname -r >> 5.2.0-rc2-gcc-8.2.0 >> >> # ./vdso_clock_getres >> clock_id: CLOCK_REALTIME [PASS] >> clock_id: CLOCK_BOOTTIME [PASS] >> clock_id: CLOCK_TAI [PASS] >> clock_id: CLOCK_REALTIME_COARSE [PASS] >> clock_id: CLOCK_MONOTONIC [PASS] >> clock_id: CLOCK_MONOTONIC_RAW [PASS] >> clock_id: CLOCK_MONOTONIC_COARSE [PASS] >> >> cheers >> >>> Cc: Shuah Khan >>> Signed-off-by: Vincenzo Frascino >>> --- >>> >>> Note: This patch is independent from the others in this series, hence it >>> can be merged singularly by the kselftest maintainers. >>> >>> tools/testing/selftests/vDSO/Makefile | 2 + >>> .../selftests/vDSO/vdso_clock_getres.c | 124 ++++++++++++++++++ >>> 2 files changed, 126 insertions(+) >>> create mode 100644 tools/testing/selftests/vDSO/vdso_clock_getres.c >