Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758169AbXIRU3Y (ORCPT ); Tue, 18 Sep 2007 16:29:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757490AbXIRU3M (ORCPT ); Tue, 18 Sep 2007 16:29:12 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:56988 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757316AbXIRU3L (ORCPT ); Tue, 18 Sep 2007 16:29:11 -0400 Date: Tue, 18 Sep 2007 22:26:45 +0200 From: Peter Zijlstra To: paulmck@linux.vnet.ibm.com Cc: Andrew Morton , Nadia Derbey , Alexey Dobriyan , linux-kernel@vger.kernel.org, Ingo Molnar Subject: [PATCH 1/2] lockdep: annotate rcu_read_lock() Message-ID: <20070918222645.4d8cbf99@lappy> In-Reply-To: <20070918182924.GF8665@linux.vnet.ibm.com> References: <20070918091728.GA6766@localhost.sw.ru> <20070918031723.05689e92.akpm@linux-foundation.org> <46EFA8DC.2020909@bull.net> <20070918033400.495b02dd.akpm@linux-foundation.org> <20070918142451.418b3b51@twins> <20070918161337.GC8665@linux.vnet.ibm.com> <20070918095715.05899d12.akpm@linux-foundation.org> <20070918182924.GF8665@linux.vnet.ibm.com> X-Mailer: Claws Mail 3.0.0 (GTK+ 2.11.6; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Bad-Reply: References and In-Reply-To but no 'Re:' in Subject. Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3118 Lines: 96 Lockdep annotate rcu_read_lock() so that it will find unbalanced locking. Signed-off-by: Peter Zijlstra --- include/linux/lockdep.h | 7 +++++++ include/linux/rcupdate.h | 12 ++++++++++++ kernel/rcupdate.c | 8 ++++++++ 3 files changed, 27 insertions(+) Index: linux-2.6/include/linux/lockdep.h =================================================================== --- linux-2.6.orig/include/linux/lockdep.h +++ linux-2.6/include/linux/lockdep.h @@ -252,6 +252,13 @@ extern void lockdep_init_map(struct lock struct lock_class_key *key, int subclass); /* + * To initialize a lockdep_map statically use this macro. + * Note that _name must not be NULL. + */ +#define STATIC_LOCKDEP_MAP_INIT(_name, _key) \ + { .name = (_name), .key = (void *)(_key), } + +/* * Reinitialize a lock key - for cases where there is special locking or * special initialization of locks so that the validator gets the scope * of dependencies wrong: they are either too broad (they need a class-split) Index: linux-2.6/include/linux/rcupdate.h =================================================================== --- linux-2.6.orig/include/linux/rcupdate.h +++ linux-2.6/include/linux/rcupdate.h @@ -41,6 +41,7 @@ #include #include #include +#include /** * struct rcu_head - callback structure for use with RCU @@ -133,6 +134,15 @@ static inline void rcu_bh_qsctr_inc(int extern int rcu_pending(int cpu); extern int rcu_needs_cpu(int cpu); +#ifdef CONFIG_DEBUG_LOCK_ALLOC +extern struct lockdep_map rcu_lock_map; +# define rcu_read_acquire() lock_acquire(&rcu_lock_map, 0, 0, 2, 1, _THIS_IP_) +# define rcu_read_release() lock_release(&rcu_lock_map, 1, _THIS_IP_) +#else +# define rcu_read_acquire() do { } while (0) +# define rcu_read_release() do { } while (0) +#endif + /** * rcu_read_lock - mark the beginning of an RCU read-side critical section. * @@ -166,6 +176,7 @@ extern int rcu_needs_cpu(int cpu); do { \ preempt_disable(); \ __acquire(RCU); \ + rcu_read_acquire(); \ } while(0) /** @@ -175,6 +186,7 @@ extern int rcu_needs_cpu(int cpu); */ #define rcu_read_unlock() \ do { \ + rcu_read_release(); \ __release(RCU); \ preempt_enable(); \ } while(0) Index: linux-2.6/kernel/rcupdate.c =================================================================== --- linux-2.6.orig/kernel/rcupdate.c +++ linux-2.6/kernel/rcupdate.c @@ -48,6 +48,14 @@ #include #include +#ifdef CONFIG_DEBUG_LOCK_ALLOC +static struct lock_class_key rcu_lock_key; +struct lockdep_map rcu_lock_map = + STATIC_LOCKDEP_MAP_INIT("rcu_read_lock", &rcu_lock_key); + +EXPORT_SYMBOL_GPL(rcu_lock_map); +#endif + /* Definition for rcupdate control block. */ static struct rcu_ctrlblk rcu_ctrlblk = { .cur = -300, - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/