From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754773AbcB2LYF (ORCPT ); Mon, 29 Feb 2016 06:24:05 -0500 Received: from torg.zytor.com ([198.137.202.12]:54880 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752305AbcB2LYD (ORCPT ); Mon, 29 Feb 2016 06:24:03 -0500 Date: Mon, 29 Feb 2016 03:23:24 -0800 From: tip-bot for Alfredo Alvarez Fernandez Message-ID: Cc: torvalds@linux-foundation.org, sasha.levin@oracle.com, mingo@kernel.org, akpm@linux-foundation.org, alfredoalvarezfernandez@gmail.com, paulmck@linux.vnet.ibm.com, hpa@zytor.com, tglx@linutronix.de, peterz@infradead.org, linux-kernel@vger.kernel.org Reply-To: sasha.levin@oracle.com, torvalds@linux-foundation.org, mingo@kernel.org, akpm@linux-foundation.org, paulmck@linux.vnet.ibm.com, alfredoalvarezfernandez@gmail.com, peterz@infradead.org, tglx@linutronix.de, hpa@zytor.com, linux-kernel@vger.kernel.org In-Reply-To: <1455864533-7536-3-git-send-email-alfredoalvarezernandez@gmail.com> References: <1455864533-7536-3-git-send-email-alfredoalvarezernandez@gmail.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:locking/core] tools/lib/lockdep: Add tests for AA and ABBA locking Git-Commit-ID: 11a1ac206d0806b0db39712c3292f6006e77a7e8 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 11a1ac206d0806b0db39712c3292f6006e77a7e8 Gitweb: http://git.kernel.org/tip/11a1ac206d0806b0db39712c3292f6006e77a7e8 Author: Alfredo Alvarez Fernandez AuthorDate: Fri, 19 Feb 2016 07:48:52 +0100 Committer: Ingo Molnar CommitDate: Mon, 29 Feb 2016 10:29:33 +0100 tools/lib/lockdep: Add tests for AA and ABBA locking Add test for AA and 2 threaded ABBA locking. Rename AA.c to ABA.c since it was implementing an ABA instead of a pure AA. Now both cases are covered. The expected output for AA.c is that the process blocks and lockdep reports a deadlock. ABBA_2threads.c differs from ABBA.c in that lockdep keeps separate chains of held locks per task. This can lead to different behaviour regarding lock detection. The expected output for this test is that the process blocks and lockdep reports a circular locking dependency. These tests found a lockdep bug - fixed by the next commit. Signed-off-by: Alfredo Alvarez Fernandez Cc: Andrew Morton Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Sasha Levin Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1455864533-7536-3-git-send-email-alfredoalvarezernandez@gmail.com Signed-off-by: Ingo Molnar --- tools/lib/lockdep/tests/AA.c | 8 +++--- tools/lib/lockdep/tests/{AA.c => ABA.c} | 0 tools/lib/lockdep/tests/ABBA_2threads.c | 46 +++++++++++++++++++++++++++++++++ 3 files changed, 50 insertions(+), 4 deletions(-) diff --git a/tools/lib/lockdep/tests/AA.c b/tools/lib/lockdep/tests/AA.c index 0f782ff..18211a5 100644 --- a/tools/lib/lockdep/tests/AA.c +++ b/tools/lib/lockdep/tests/AA.c @@ -1,13 +1,13 @@ #include -void main(void) +int main(void) { - pthread_mutex_t a, b; + pthread_mutex_t a; pthread_mutex_init(&a, NULL); - pthread_mutex_init(&b, NULL); pthread_mutex_lock(&a); - pthread_mutex_lock(&b); pthread_mutex_lock(&a); + + return 0; } diff --git a/tools/lib/lockdep/tests/AA.c b/tools/lib/lockdep/tests/ABA.c similarity index 100% copy from tools/lib/lockdep/tests/AA.c copy to tools/lib/lockdep/tests/ABA.c diff --git a/tools/lib/lockdep/tests/ABBA_2threads.c b/tools/lib/lockdep/tests/ABBA_2threads.c new file mode 100644 index 0000000..cd807d7 --- /dev/null +++ b/tools/lib/lockdep/tests/ABBA_2threads.c @@ -0,0 +1,46 @@ +#include +#include + +pthread_mutex_t a = PTHREAD_MUTEX_INITIALIZER; +pthread_mutex_t b = PTHREAD_MUTEX_INITIALIZER; +pthread_barrier_t bar; + +void *ba_lock(void *arg) +{ + int ret, i; + + pthread_mutex_lock(&b); + + if (pthread_barrier_wait(&bar) == PTHREAD_BARRIER_SERIAL_THREAD) + pthread_barrier_destroy(&bar); + + pthread_mutex_lock(&a); + + pthread_mutex_unlock(&a); + pthread_mutex_unlock(&b); +} + +int main(void) +{ + pthread_t t; + + pthread_barrier_init(&bar, NULL, 2); + + if (pthread_create(&t, NULL, ba_lock, NULL)) { + fprintf(stderr, "pthread_create() failed\n"); + return 1; + } + pthread_mutex_lock(&a); + + if (pthread_barrier_wait(&bar) == PTHREAD_BARRIER_SERIAL_THREAD) + pthread_barrier_destroy(&bar); + + pthread_mutex_lock(&b); + + pthread_mutex_unlock(&b); + pthread_mutex_unlock(&a); + + pthread_join(t, NULL); + + return 0; +}