From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755548AbdK2PkC (ORCPT ); Wed, 29 Nov 2017 10:40:02 -0500 Received: from Galois.linutronix.de ([146.0.238.70]:39859 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933138AbdK2PcQ (ORCPT ); Wed, 29 Nov 2017 10:32:16 -0500 From: Anna-Maria Gleixner To: LKML Cc: Thomas Gleixner , Peter Zijlstra , Ingo Molnar , keescook@chromium.org, Christoph Hellwig , John Stultz , Anna-Maria Gleixner Subject: [PATCH v3 21/36] hrtimer: Make remote enqueue decision less restrictive Date: Wed, 29 Nov 2017 16:30:46 +0100 Message-Id: <20171129153101.27297-22-anna-maria@linutronix.de> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20171129153101.27297-1-anna-maria@linutronix.de> References: <20171129153101.27297-1-anna-maria@linutronix.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The current decision whether a timer can be queued on a remote CPU checks for timer->expiry <= remote_cpu_base.expires_next. This is too restrictive because a timer with the same expiry time as an existing timer will be enqueued on right-hand size of the existing timer inside the rbtree, i.e. behind the first expiring timer. So its safe to allow enqueuing timers with the same expiry time as the first expiring timer on a remote CPU base. Signed-off-by: Anna-Maria Gleixner --- kernel/time/hrtimer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 90a8aa9a7fa2..e0521d8f247b 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -168,7 +168,7 @@ hrtimer_check_target(struct hrtimer *timer, struct hrtimer_clock_base *new_base) ktime_t expires; expires = ktime_sub(hrtimer_get_expires(timer), new_base->offset); - return expires <= new_base->cpu_base->expires_next; + return expires < new_base->cpu_base->expires_next; } static inline -- 2.11.0