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Received: from smtp-auth.mailprotect.be ([178.208.39.155]) by com-mpt-out001.mailprotect.be with esmtp (Exim 4.89) (envelope-from ) id 1gV4hS-0008of-15; Fri, 07 Dec 2018 02:13:02 +0100 Received: from desktop-bart.svl.corp.google.com (unknown [104.133.8.89]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp-auth.mailprotect.be (Postfix) with ESMTPSA id 27FA5C0787; Fri, 7 Dec 2018 02:12:59 +0100 (CET) From: Bart Van Assche To: mingo@redhat.com Cc: peterz@infradead.org, tj@kernel.org, longman@redhat.com, johannes.berg@intel.com, linux-kernel@vger.kernel.org, Bart Van Assche , Johannes Berg Subject: [PATCH v3 12/24] locking/lockdep: Make concurrent lockdep_reset_lock() calls safe Date: Thu, 6 Dec 2018 17:11:36 -0800 Message-Id: <20181207011148.251812-13-bvanassche@acm.org> X-Mailer: git-send-email 2.20.0.rc2.403.gdbc3b29805-goog In-Reply-To: <20181207011148.251812-1-bvanassche@acm.org> References: <20181207011148.251812-1-bvanassche@acm.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Originating-IP: 178.208.39.155 X-SpamExperts-Domain: mailprotect.be X-SpamExperts-Username: 178.208.39.128/27 Authentication-Results: mailprotect.be; 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Cc: Peter Zijlstra Cc: Waiman Long Cc: Johannes Berg Signed-off-by: Bart Van Assche --- kernel/locking/lockdep.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 346b5a1fd062..737d2dd3ea56 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -4122,6 +4122,9 @@ void lockdep_reset(void) raw_local_irq_restore(flags); } +/* + * Remove all references to a lock class. The caller must hold the graph lock. + */ static void zap_class(struct lock_class *class) { int i; @@ -4229,6 +4232,7 @@ void lockdep_reset_lock(struct lockdep_map *lock) int j, locked; raw_local_irq_save(flags); + locked = graph_lock(); /* * Remove all classes this lock might have: @@ -4245,7 +4249,6 @@ void lockdep_reset_lock(struct lockdep_map *lock) * Debug check: in the end all mapped classes should * be gone. */ - locked = graph_lock(); if (unlikely(lock_class_cache_is_registered(lock))) { if (debug_locks_off_graph_unlock()) { /* -- 2.20.0.rc2.403.gdbc3b29805-goog