From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751432AbdANIqw (ORCPT ); Sat, 14 Jan 2017 03:46:52 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:54908 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750885AbdANIqu (ORCPT ); Sat, 14 Jan 2017 03:46:50 -0500 From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@kernel.org, jiangshanlai@gmail.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, dvhart@linux.intel.com, fweisbec@gmail.com, oleg@redhat.com, bobby.prani@gmail.com, "Paul E. McKenney" Subject: [PATCH RFC v2 tip/core/rcu 1/2] rcu: Remove cond_resched() from Tiny synchronize_sched() Date: Sat, 14 Jan 2017 00:45:53 -0800 X-Mailer: git-send-email 2.5.2 In-Reply-To: <20161114183636.GA28589@linux.vnet.ibm.com@> References: <20161114183636.GA28589@linux.vnet.ibm.com@> X-TM-AS-GCONF: 00 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 17011408-0012-0000-0000-0000135B0F84 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00006430; HX=3.00000240; KW=3.00000007; PH=3.00000004; SC=3.00000199; SDB=6.00807460; UDB=6.00393072; IPR=6.00584799; BA=6.00005055; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00013919; XFM=3.00000011; UTC=2017-01-14 08:46:00 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17011408-0013-0000-0000-00004A83DC79 Message-Id: <1484383554-18095-1-git-send-email-paulmck@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-01-14_01:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=1 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1612050000 definitions=main-1701140127 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org It is now legal to invoke synchronize_sched() at early boot, which causes Tiny RCU's synchronize_sched() to emit spurious splats. This commit therefore removes the cond_resched() from Tiny RCU's synchronize_sched(). Signed-off-by: Paul E. McKenney --- kernel/rcu/tiny.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c index 1898559e6b60..b23a4d076f3d 100644 --- a/kernel/rcu/tiny.c +++ b/kernel/rcu/tiny.c @@ -185,9 +185,6 @@ static __latent_entropy void rcu_process_callbacks(struct softirq_action *unused * benefits of doing might_sleep() to reduce latency.) * * Cool, huh? (Due to Josh Triplett.) - * - * But we want to make this a static inline later. The cond_resched() - * currently makes this problematic. */ void synchronize_sched(void) { @@ -195,7 +192,6 @@ void synchronize_sched(void) lock_is_held(&rcu_lock_map) || lock_is_held(&rcu_sched_lock_map), "Illegal synchronize_sched() in RCU read-side critical section"); - cond_resched(); } EXPORT_SYMBOL_GPL(synchronize_sched); -- 2.5.2