From patchwork Wed Feb 12 22:34:39 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anchal Agarwal X-Patchwork-Id: 11379309 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id ED07A14E3 for ; Wed, 12 Feb 2020 22:35:33 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C9AA021734 for ; Wed, 12 Feb 2020 22:35:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b="tD+1J8/G" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C9AA021734 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=amazon.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1j20ao-0003e1-4S; Wed, 12 Feb 2020 22:34:50 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1j20am-0003dh-Fg for xen-devel@lists.xenproject.org; Wed, 12 Feb 2020 22:34:48 +0000 X-Inumbo-ID: dfc79236-4de7-11ea-b803-12813bfff9fa Received: from smtp-fw-9101.amazon.com (unknown [207.171.184.25]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id dfc79236-4de7-11ea-b803-12813bfff9fa; Wed, 12 Feb 2020 22:34:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1581546888; x=1613082888; h=date:from:to:subject:message-id:mime-version; bh=tYSU9iIsoDiHOrDtUYIpPVrJzHedrCrd1HEsqWaOGf0=; b=tD+1J8/GbJodCU7B5y1Kbz1Bu64/n3fcoZneWvH4rFY7ChaexmiKoAxJ rKdflZjgdYrtWXGR4A2BQH/vSMMEAXA2E26PnAKAbBp+1IakhRrcw5G0F 37FqG1v2wRGviETPJfk4R0MiKIj+dY6/75KopLV/AqoCjbkE98hCYl67X 8=; IronPort-SDR: bkSrtJsJHpidimijd2L1wIMETSIqwjC5vVxq1oCoMg6L/owqJK4HB0Xj7VHCDOcGTayR5JOFV8 X4CMSFr17QNw== X-IronPort-AV: E=Sophos;i="5.70,434,1574121600"; d="scan'208";a="16328108" Received: from sea32-co-svc-lb4-vlan3.sea.corp.amazon.com (HELO email-inbound-relay-2a-538b0bfb.us-west-2.amazon.com) ([10.47.23.38]) by smtp-border-fw-out-9101.sea19.amazon.com with ESMTP; 12 Feb 2020 22:34:47 +0000 Received: from EX13MTAUWC001.ant.amazon.com (pdx4-ws-svc-p6-lb7-vlan3.pdx.amazon.com [10.170.41.166]) by email-inbound-relay-2a-538b0bfb.us-west-2.amazon.com (Postfix) with ESMTPS id E0121A28F3; Wed, 12 Feb 2020 22:34:45 +0000 (UTC) Received: from EX13D05UWC001.ant.amazon.com (10.43.162.82) by EX13MTAUWC001.ant.amazon.com (10.43.162.135) with Microsoft SMTP Server (TLS) id 15.0.1367.3; Wed, 12 Feb 2020 22:34:39 +0000 Received: from EX13MTAUWC001.ant.amazon.com (10.43.162.135) by EX13D05UWC001.ant.amazon.com (10.43.162.82) with Microsoft SMTP Server (TLS) id 15.0.1367.3; Wed, 12 Feb 2020 22:34:39 +0000 Received: from dev-dsk-anchalag-2a-9c2d1d96.us-west-2.amazon.com (172.22.96.68) by mail-relay.amazon.com (10.43.162.232) with Microsoft SMTP Server id 15.0.1367.3 via Frontend Transport; Wed, 12 Feb 2020 22:34:39 +0000 Received: by dev-dsk-anchalag-2a-9c2d1d96.us-west-2.amazon.com (Postfix, from userid 4335130) id 83531400D1; Wed, 12 Feb 2020 22:34:39 +0000 (UTC) Date: Wed, 12 Feb 2020 22:34:39 +0000 From: Anchal Agarwal To: , , , , , , , , , , , , , , , , , , , , , , , , , , , , Message-ID: <20200212223439.GA4444@dev-dsk-anchalag-2a-9c2d1d96.us-west-2.amazon.com> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Precedence: Bulk Subject: [Xen-devel] [RFC PATCH v3 10/12] xen: Introduce wrapper for save/restore sched clock offset X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" Introduce wrappers for save/restore xen_sched_clock_offset to be used by PM hibernation code to avoid system instability during resume. Signed-off-by: Anchal Agarwal --- Changes since V2: * Dropped marking tsc unstable during hibernation patch * Fixed issue with xen_sched_clock_offset during suspend/resume * On further interrogation and testing, the issue wasn't with tsc being stable/unstable --- arch/x86/xen/time.c | 15 +++++++++++++-- arch/x86/xen/xen-ops.h | 2 ++ 2 files changed, 15 insertions(+), 2 deletions(-) diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c index 8cf632dda605..eeb6d3d2eaab 100644 --- a/arch/x86/xen/time.c +++ b/arch/x86/xen/time.c @@ -379,12 +379,23 @@ static const struct pv_time_ops xen_time_ops __initconst = { static struct pvclock_vsyscall_time_info *xen_clock __read_mostly; static u64 xen_clock_value_saved; +/*This is needed to maintain a monotonic clock value during PM hibernation */ +void xen_save_sched_clock_offset(void) +{ + xen_clock_value_saved = xen_clocksource_read() - xen_sched_clock_offset; +} + +void xen_restore_sched_clock_offset(void) +{ + xen_sched_clock_offset = xen_clocksource_read() - xen_clock_value_saved; +} + void xen_save_time_memory_area(void) { struct vcpu_register_time_memory_area t; int ret; - xen_clock_value_saved = xen_clocksource_read() - xen_sched_clock_offset; + xen_save_sched_clock_offset(); if (!xen_clock) return; @@ -426,7 +437,7 @@ void xen_restore_time_memory_area(void) out: /* Need pvclock_resume() before using xen_clocksource_read(). */ pvclock_resume(); - xen_sched_clock_offset = xen_clocksource_read() - xen_clock_value_saved; + xen_restore_sched_clock_offset(); } static void xen_setup_vsyscall_time_info(void) diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h index d84c357994bd..9f49124df033 100644 --- a/arch/x86/xen/xen-ops.h +++ b/arch/x86/xen/xen-ops.h @@ -72,6 +72,8 @@ void xen_save_time_memory_area(void); void xen_restore_time_memory_area(void); void xen_init_time_ops(void); void xen_hvm_init_time_ops(void); +void xen_save_sched_clock_offset(void); +void xen_restore_sched_clock_offset(void); irqreturn_t xen_debug_interrupt(int irq, void *dev_id);