From patchwork Wed May 11 20:59:35 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Paul E. McKenney" X-Patchwork-Id: 1462 Return-Path: Delivered-To: unknown Received: from imap.gmail.com (74.125.159.109) by localhost6.localdomain6 with IMAP4-SSL; 08 Jun 2011 14:52:09 -0000 Delivered-To: patches@linaro.org Received: by 10.224.61.3 with SMTP id r3cs81375qah; Wed, 11 May 2011 13:59:46 -0700 (PDT) Received: by 10.236.79.72 with SMTP id h48mr11153649yhe.491.1305147585921; Wed, 11 May 2011 13:59:45 -0700 (PDT) Received: from e5.ny.us.ibm.com (e5.ny.us.ibm.com [32.97.182.145]) by mx.google.com with ESMTPS id j44si1353743yhe.6.2011.05.11.13.59.45 (version=TLSv1/SSLv3 cipher=OTHER); Wed, 11 May 2011 13:59:45 -0700 (PDT) Received-SPF: pass (google.com: domain of paulmck@linux.vnet.ibm.com designates 32.97.182.145 as permitted sender) client-ip=32.97.182.145; Authentication-Results: mx.google.com; spf=pass (google.com: domain of paulmck@linux.vnet.ibm.com designates 32.97.182.145 as permitted sender) smtp.mail=paulmck@linux.vnet.ibm.com Received: from d01relay03.pok.ibm.com (d01relay03.pok.ibm.com [9.56.227.235]) by e5.ny.us.ibm.com (8.14.4/8.13.1) with ESMTP id p4BKWwdb003712 for ; Wed, 11 May 2011 16:32:58 -0400 Received: from d01av01.pok.ibm.com (d01av01.pok.ibm.com [9.56.224.215]) by d01relay03.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p4BKxjYY097240 for ; Wed, 11 May 2011 16:59:45 -0400 Received: from d01av01.pok.ibm.com (loopback [127.0.0.1]) by d01av01.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p4BKxfCX009034 for ; Wed, 11 May 2011 16:59:44 -0400 Received: from paulmck-ThinkPad-W500 (sig-9-76-195-154.mts.ibm.com [9.76.195.154]) by d01av01.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id p4BKxefX008978; Wed, 11 May 2011 16:59:40 -0400 Received: by paulmck-ThinkPad-W500 (Postfix, from userid 1000) id 8C93913F7C6; Wed, 11 May 2011 13:59:39 -0700 (PDT) From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@elte.hu, laijs@cn.fujitsu.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@polymtl.ca, josh@joshtriplett.org, niv@us.ibm.com, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, Valdis.Kletnieks@vt.edu, dhowells@redhat.com, eric.dumazet@gmail.com, darren@dvhart.com, patches@linaro.org, "Paul E. McKenney" Subject: [PATCH tip/core/rcu 1/3] rcu: avoid build error for third-party modules Date: Wed, 11 May 2011 13:59:35 -0700 Message-Id: <1305147577-1812-1-git-send-email-paulmck@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.3.2 In-Reply-To: <20110511205915.GA1731@linux.vnet.ibm.com> References: <20110511205915.GA1731@linux.vnet.ibm.com> The initial definition of __kfree_rcu() checked a static inline function argument to see if it was a compile-time constant. Apparently not all compilers are willing to put up with this at all optimization levels. Add a nasty comment and remove the warning, relying on the fact that __kfree_rcu() is called only from kfree_rcu(), which always passes in a compile-time constant. Signed-off-by: Paul E. McKenney --- include/linux/rcupdate.h | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 99f9aa7..58b13f1 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -814,13 +814,14 @@ static __always_inline bool __is_kfree_rcu_offset(unsigned long offset) return offset < 4096; } +/* + * Intended to be called only from the kfree_rcu() macro. + */ static __always_inline void __kfree_rcu(struct rcu_head *head, unsigned long offset) { typedef void (*rcu_callback)(struct rcu_head *); - BUILD_BUG_ON(!__builtin_constant_p(offset)); - /* See the kfree_rcu() header comment. */ BUILD_BUG_ON(!__is_kfree_rcu_offset(offset));