From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steven Rostedt Subject: [PATCH RT 7/9] rt/locking: allow recursive local_trylock() Date: Fri, 01 Dec 2017 20:37:05 -0500 Message-ID: <20171202013712.321246203@goodmis.org> References: <20171202013658.149533964@goodmis.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Cc: Thomas Gleixner , Carsten Emde , Sebastian Andrzej Siewior , John Kacur , Paul Gortmaker , Julia Cartwright , Daniel Wagner , tom.zanussi@linux.intel.com, Alex Shi , stable-rt@vger.kernel.org To: linux-kernel@vger.kernel.org, linux-rt-users Return-path: Received: from mail.kernel.org ([198.145.29.99]:48872 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752005AbdLBBhN (ORCPT ); Fri, 1 Dec 2017 20:37:13 -0500 Content-Disposition: inline; filename=0007-rt-locking-allow-recursive-local_trylock.patch Sender: linux-rt-users-owner@vger.kernel.org List-ID: 4.4.102-rt117-rc1 stable review patch. If anyone has any objections, please let me know. ------------------ From: Sebastian Andrzej Siewior required for following networking patch which does recursive try-lock. While at it, add the !RT version of it because it did not yet exist. Cc: stable-rt@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior --- include/linux/locallock.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/include/linux/locallock.h b/include/linux/locallock.h index e572a3971631..0baaf28dc4ee 100644 --- a/include/linux/locallock.h +++ b/include/linux/locallock.h @@ -77,6 +77,9 @@ static inline int __local_trylock(struct local_irq_lock *lv) lv->owner = current; lv->nestcnt = 1; return 1; + } else if (lv->owner == current) { + lv->nestcnt++; + return 1; } return 0; } @@ -250,6 +253,12 @@ static inline int __local_unlock_irqrestore(struct local_irq_lock *lv, static inline void local_irq_lock_init(int lvar) { } +#define local_trylock(lvar) \ + ({ \ + preempt_disable(); \ + 1; \ + }) + #define local_lock(lvar) preempt_disable() #define local_unlock(lvar) preempt_enable() #define local_lock_irq(lvar) local_irq_disable() -- 2.13.2