Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753183AbaBQOMB (ORCPT ); Mon, 17 Feb 2014 09:12:01 -0500 Received: from userp1040.oracle.com ([156.151.31.81]:43515 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750830AbaBQOMA (ORCPT ); Mon, 17 Feb 2014 09:12:00 -0500 From: Boris Ostrovsky To: mingo@redhat.com, peterz@infradead.org Cc: linux-kernel@vger.kernel.org, konrad.wilk@oracle.com, boris.ostrovsky@oracle.com Subject: [PATCH] sched/deadline: Test for CPU's presence explicitly Date: Mon, 17 Feb 2014 09:12:33 -0500 Message-Id: <1392646353-1874-1-git-send-email-boris.ostrovsky@oracle.com> X-Mailer: git-send-email 1.8.1.4 X-Source-IP: ucsinet22.oracle.com [156.151.31.94] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org A hot-removed CPU may have ID that is numerically larger than the number of existing CPUs in the system (e.g. we can unplug CPU 4 from a system that has CPUs 0, 1 and 4). Thus the WARN_ONs should check whether the CPU in question is currently present, not whether its ID value is less than num_present_cpus(). Reported-by: Konrad Rzeszutek Wilk Signed-off-by: Boris Ostrovsky --- kernel/sched/cpudeadline.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c index 045fc74..5b8838b 100644 --- a/kernel/sched/cpudeadline.c +++ b/kernel/sched/cpudeadline.c @@ -70,7 +70,7 @@ static void cpudl_heapify(struct cpudl *cp, int idx) static void cpudl_change_key(struct cpudl *cp, int idx, u64 new_dl) { - WARN_ON(idx > num_present_cpus() || idx == IDX_INVALID); + WARN_ON(!cpu_present(idx) || idx == IDX_INVALID); if (dl_time_before(new_dl, cp->elements[idx].dl)) { cp->elements[idx].dl = new_dl; @@ -117,7 +117,7 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p, } out: - WARN_ON(best_cpu > num_present_cpus() && best_cpu != -1); + WARN_ON(!cpu_present(best_cpu) && best_cpu != -1); return best_cpu; } @@ -137,7 +137,7 @@ void cpudl_set(struct cpudl *cp, int cpu, u64 dl, int is_valid) int old_idx, new_cpu; unsigned long flags; - WARN_ON(cpu > num_present_cpus()); + WARN_ON(!cpu_present(cpu)); raw_spin_lock_irqsave(&cp->lock, flags); old_idx = cp->cpu_to_idx[cpu]; -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/