From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-20.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2F910C49361 for ; Fri, 18 Jun 2021 11:24:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0ECC161248 for ; Fri, 18 Jun 2021 11:24:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234048AbhFRL0W (ORCPT ); Fri, 18 Jun 2021 07:26:22 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:55038 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234001AbhFRL0O (ORCPT ); Fri, 18 Jun 2021 07:26:14 -0400 Date: Fri, 18 Jun 2021 11:24:03 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1624015444; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ZR6oELuwkW7w79xFGGRD+NGTdIakf+EWLs1EYMdVTPA=; b=GgEbZcsJBifFS9ReFobwt2w5MfBIgRMohuN/3IPD6ATfjQcvA9GgbLbm4HSl7PdKc0Hy4D WydQFR4v3I24aAuoh64iW4tSJjsLfFZQuN8MofSbgPORyXy9tOjyDmxk/Vd6ASUjqphK5n 6AZ+EtMg2BLL3+//Lwk5ciGvcOBPy91nrJgFQDxuHEZ9OdybXtp5PDcy84h5q08Hc3v3A9 W9JfnWwX1ErWYcFjoyW7IQa2yjdJIRMUgNAi0kR8CdYaXQ9Cie9fPbI7gX0U+DjJply4PT oiy1yPcbn7RG1nJ4lYs9T+QwdVcqrXI9YwvErxqSfAeRtKvEdNFbKMwhxLp1/g== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1624015444; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ZR6oELuwkW7w79xFGGRD+NGTdIakf+EWLs1EYMdVTPA=; b=V92/XsppnnKbulTg/8o7hnltpdlNRtXpWgylTuafPhtAu7XqpZjYWfrOj6x39ptH59/SCN HvpkrcyJ0AwVCfDw== From: "tip-bot2 for Peter Zijlstra" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: sched/core] sched,perf,kvm: Fix preemption condition Cc: "Peter Zijlstra (Intel)" , Mark Rutland , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20210611082838.285099381@infradead.org> References: <20210611082838.285099381@infradead.org> MIME-Version: 1.0 Message-ID: <162401544396.19906.14021527012259454118.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the sched/core branch of tip: Commit-ID: 3ba9f93b12361e005dd65fcc8072b42e3189f4f4 Gitweb: https://git.kernel.org/tip/3ba9f93b12361e005dd65fcc8072b42e3189f4f4 Author: Peter Zijlstra AuthorDate: Fri, 11 Jun 2021 10:28:13 +02:00 Committer: Peter Zijlstra CommitterDate: Fri, 18 Jun 2021 11:43:07 +02:00 sched,perf,kvm: Fix preemption condition When ran from the sched-out path (preempt_notifier or perf_event), p->state is irrelevant to determine preemption. You can get preempted with !task_is_running() just fine. The right indicator for preemption is if the task is still on the runqueue in the sched-out path. Signed-off-by: Peter Zijlstra (Intel) Acked-by: Mark Rutland Link: https://lore.kernel.org/r/20210611082838.285099381@infradead.org --- kernel/events/core.c | 7 +++---- virt/kvm/kvm_main.c | 2 +- 2 files changed, 4 insertions(+), 5 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index fe88d6e..fd89000 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -8682,13 +8682,12 @@ static void perf_event_switch(struct task_struct *task, }, }; - if (!sched_in && task->state == TASK_RUNNING) + if (!sched_in && task->on_rq) { switch_event.event_id.header.misc |= PERF_RECORD_MISC_SWITCH_OUT_PREEMPT; + } - perf_iterate_sb(perf_event_switch_output, - &switch_event, - NULL); + perf_iterate_sb(perf_event_switch_output, &switch_event, NULL); } /* diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 6a6bc7a..5f166eb 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -5025,7 +5025,7 @@ static void kvm_sched_out(struct preempt_notifier *pn, { struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn); - if (current->state == TASK_RUNNING) { + if (current->on_rq) { WRITE_ONCE(vcpu->preempted, true); WRITE_ONCE(vcpu->ready, true); }