From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754127AbeDWDDk (ORCPT ); Sun, 22 Apr 2018 23:03:40 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:39588 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754016AbeDWDCo (ORCPT ); Sun, 22 Apr 2018 23:02:44 -0400 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, fweisbec@gmail.com, oleg@redhat.com, joel.opensrc@gmail.com, torvalds@linux-foundation.org, npiggin@gmail.com, "Paul E. McKenney" Subject: [PATCH tip/core/rcu 20/21] rcu: Drop early GP request check from rcu_gp_kthread() Date: Sun, 22 Apr 2018 20:03:43 -0700 X-Mailer: git-send-email 2.5.2 In-Reply-To: <20180423030258.GA23370@linux.vnet.ibm.com> References: <20180423030258.GA23370@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 18042303-0040-0000-0000-000004207441 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00008903; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000257; SDB=6.01021898; UDB=6.00521542; IPR=6.00801134; MB=3.00020719; MTD=3.00000008; XFM=3.00000015; UTC=2018-04-23 03:02:38 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18042303-0041-0000-0000-000008267DB1 Message-Id: <1524452624-27589-20-git-send-email-paulmck@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-04-23_01:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1709140000 definitions=main-1804230032 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Now that grace-period requests use funnel locking and now that they set ->gp_flags to RCU_GP_FLAG_INIT even when the RCU grace-period kthread has not yet started, rcu_gp_kthread() no longer needs to check need_any_future_gp() at startup time. This commit therefore removes this check. Signed-off-by: Paul E. McKenney --- kernel/rcu/tree.c | 6 ------ 1 file changed, 6 deletions(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 020a0fe2dbee..ed238886e6ca 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -2135,12 +2135,6 @@ static int __noreturn rcu_gp_kthread(void *arg) struct rcu_state *rsp = arg; struct rcu_node *rnp = rcu_get_root(rsp); - /* Check for early-boot work. */ - raw_spin_lock_irq_rcu_node(rnp); - if (need_any_future_gp(rnp)) - WRITE_ONCE(rsp->gp_flags, RCU_GP_FLAG_INIT); - raw_spin_unlock_irq_rcu_node(rnp); - rcu_bind_gp_kthread(); for (;;) { -- 2.5.2