From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932611AbbCCRyB (ORCPT ); Tue, 3 Mar 2015 12:54:01 -0500 Received: from e32.co.us.ibm.com ([32.97.110.150]:54419 "EHLO e32.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932580AbbCCRxp (ORCPT ); Tue, 3 Mar 2015 12:53:45 -0500 From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@kernel.org, laijs@cn.fujitsu.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, Alexander Gordeev , "Paul E. McKenney" Subject: [PATCH tip/core/rcu 2/2] rcu: Remove fastpath from __rcu_process_callbacks() Date: Tue, 3 Mar 2015 09:53:36 -0800 Message-Id: <1425405216-19953-2-git-send-email-paulmck@linux.vnet.ibm.com> X-Mailer: git-send-email 1.8.1.5 In-Reply-To: <1425405216-19953-1-git-send-email-paulmck@linux.vnet.ibm.com> References: <20150303175313.GA19474@linux.vnet.ibm.com> <1425405216-19953-1-git-send-email-paulmck@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15030317-0005-0000-0000-0000093C96EC Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Alexander Gordeev The standard code path accommodates a condition when no RCU callbacks are ready to invoke. Since size of the code is a priority for tiny RCU, remove the fast path. Cc: "Paul E. McKenney" Signed-off-by: Alexander Gordeev Signed-off-by: Paul E. McKenney --- kernel/rcu/tiny.c | 11 ----------- 1 file changed, 11 deletions(-) diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c index d4e7fe5f3baf..069742d61c68 100644 --- a/kernel/rcu/tiny.c +++ b/kernel/rcu/tiny.c @@ -168,17 +168,6 @@ static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp) unsigned long flags; RCU_TRACE(int cb_count = 0); - /* If no RCU callbacks ready to invoke, just return. */ - if (&rcp->rcucblist == rcp->donetail) { - RCU_TRACE(trace_rcu_batch_start(rcp->name, 0, 0, -1)); - RCU_TRACE(trace_rcu_batch_end(rcp->name, 0, - !!ACCESS_ONCE(rcp->rcucblist), - need_resched(), - is_idle_task(current), - false)); - return; - } - /* Move the ready-to-invoke callbacks to a local list. */ local_irq_save(flags); RCU_TRACE(trace_rcu_batch_start(rcp->name, 0, rcp->qlen, -1)); -- 1.8.1.5