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=-11.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,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 E6701C433FF for ; Tue, 30 Jul 2019 22:14:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B5AB0205C9 for ; Tue, 30 Jul 2019 22:14:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=zytor.com header.i=@zytor.com header.b="pMBiGW5Z" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728936AbfG3WO1 (ORCPT ); Tue, 30 Jul 2019 18:14:27 -0400 Received: from terminus.zytor.com ([198.137.202.136]:49929 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726253AbfG3WO0 (ORCPT ); Tue, 30 Jul 2019 18:14:26 -0400 Received: from terminus.zytor.com (localhost [127.0.0.1]) by terminus.zytor.com (8.15.2/8.15.2) with ESMTPS id x6UMEE4E3398533 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Tue, 30 Jul 2019 15:14:14 -0700 DKIM-Filter: OpenDKIM Filter v2.11.0 terminus.zytor.com x6UMEE4E3398533 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zytor.com; s=2019071901; t=1564524855; bh=cF7qerniqPcTQ2Ids6LvC+O9ZTrvolsR9NL6jnK2dM4=; h=Date:From:Cc:Reply-To:In-Reply-To:References:To:Subject:From; b=pMBiGW5ZM6KpIMb7WcYDY2Jj5YMSSFK6eR5Ul60NmoQzwPLL+79wD3ZqttucWdQyZ UkSt7TCBd7EihzSRnqrzzH30mfa9XiV4k4Eag8EC3thp30CRX0gNeJbM7P17Ftw36S jHBhnq0PCXzAOI5olp9s8ml+96MpQkEn89wLFulDzxOLnaJYUCA1z6BV1K7O2fnQkX +wLi7LxTVKJZghCtCjHTP/VTs8nJykwWXyyeLy6UHs9WAxhtB8ackLCBXU9PdujySB lNiBFgN3kE2Uo5PMum3hNMgKTXs/2oHA751GWcsPQTWzNXdJFWVzNuvhQ0OphvH2Dz TzsxLJ7u41WlQ== Received: (from tipbot@localhost) by terminus.zytor.com (8.15.2/8.15.2/Submit) id x6UMECBf3398530; Tue, 30 Jul 2019 15:14:12 -0700 Date: Tue, 30 Jul 2019 15:14:12 -0700 X-Authentication-Warning: terminus.zytor.com: tipbot set sender to tipbot@zytor.com using -f From: tip-bot for Sebastian Andrzej Siewior Message-ID: Cc: linux-kernel@vger.kernel.org, bigeasy@linutronix.de, pbonzini@redhat.com, tglx@linutronix.de, hpa@zytor.com, mingo@kernel.org, peterz@infradead.org Reply-To: hpa@zytor.com, pbonzini@redhat.com, tglx@linutronix.de, mingo@kernel.org, peterz@infradead.org, linux-kernel@vger.kernel.org, bigeasy@linutronix.de In-Reply-To: <20190726185753.363363474@linutronix.de> References: <20190726185753.363363474@linutronix.de> To: linux-tip-commits@vger.kernel.org Subject: [tip:timers/core] KVM: LAPIC: Mark hrtimer to expire in hard interrupt context Git-Commit-ID: 899ad4bce00d10433b64647a37f6488dd8b582c9 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 899ad4bce00d10433b64647a37f6488dd8b582c9 Gitweb: https://git.kernel.org/tip/899ad4bce00d10433b64647a37f6488dd8b582c9 Author: Sebastian Andrzej Siewior AuthorDate: Fri, 26 Jul 2019 20:30:55 +0200 Committer: Thomas Gleixner CommitDate: Tue, 30 Jul 2019 23:57:55 +0200 KVM: LAPIC: Mark hrtimer to expire in hard interrupt context On PREEMPT_RT enabled kernels unmarked hrtimers are moved into soft interrupt expiry mode by default. While that's not a functional requirement for the KVM local APIC timer emulation, it's a latency issue which can be avoided by marking the timer so hard interrupt context expiry is enforced. No functional change. [ tglx: Split out from larger combo patch. Add changelog. ] Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Acked-by: Paolo Bonzini Acked-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20190726185753.363363474@linutronix.de --- arch/x86/kvm/lapic.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 0aa158657f20..b9e516099d07 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1601,7 +1601,7 @@ static void start_sw_tscdeadline(struct kvm_lapic *apic) likely(ns > apic->lapic_timer.timer_advance_ns)) { expire = ktime_add_ns(now, ns); expire = ktime_sub_ns(expire, ktimer->timer_advance_ns); - hrtimer_start(&ktimer->timer, expire, HRTIMER_MODE_ABS); + hrtimer_start(&ktimer->timer, expire, HRTIMER_MODE_ABS_HARD); } else apic_timer_expired(apic); @@ -2302,7 +2302,7 @@ int kvm_create_lapic(struct kvm_vcpu *vcpu, int timer_advance_ns) apic->vcpu = vcpu; hrtimer_init(&apic->lapic_timer.timer, CLOCK_MONOTONIC, - HRTIMER_MODE_ABS); + HRTIMER_MODE_ABS_HARD); apic->lapic_timer.timer.function = apic_timer_fn; if (timer_advance_ns == -1) { apic->lapic_timer.timer_advance_ns = LAPIC_TIMER_ADVANCE_ADJUST_INIT; @@ -2487,7 +2487,7 @@ void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu) timer = &vcpu->arch.apic->lapic_timer.timer; if (hrtimer_cancel(timer)) - hrtimer_start_expires(timer, HRTIMER_MODE_ABS); + hrtimer_start_expires(timer, HRTIMER_MODE_ABS_HARD); } /*