From patchwork Fri Aug 21 22:30:11 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anchal Agarwal X-Patchwork-Id: 11730725 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 8B0C3913 for ; Fri, 21 Aug 2020 22:30:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6FB28207CD for ; Fri, 21 Aug 2020 22:30:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b="th2zwfUU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726867AbgHUWau (ORCPT ); Fri, 21 Aug 2020 18:30:50 -0400 Received: from smtp-fw-9102.amazon.com ([207.171.184.29]:36187 "EHLO smtp-fw-9102.amazon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726747AbgHUWat (ORCPT ); Fri, 21 Aug 2020 18:30:49 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1598049048; x=1629585048; h=date:from:to:subject:message-id:references:mime-version: in-reply-to; bh=fYlNM/Ki+IOGvkGZqz//RrR1UMvb0Rd2rCL0FP2g5T0=; b=th2zwfUU2hqeMVvZ3RVGljESXhHg4OyUkT+dScR8A0KtocqIAspcsz2j tLUzAukLBfU3M7miyHcVmUQnvEBM1CJX9EWYjh3TiYO763kZ18PMbqorl ysGPvYGwMo9oM+SSt3QmwUaQl+zto8OyAGDgQNh39SkW6sDBT1uv9MJzU I=; X-IronPort-AV: E=Sophos;i="5.76,338,1592870400"; d="scan'208";a="69983166" Received: from sea32-co-svc-lb4-vlan3.sea.corp.amazon.com (HELO email-inbound-relay-1a-821c648d.us-east-1.amazon.com) ([10.47.23.38]) by smtp-border-fw-out-9102.sea19.amazon.com with ESMTP; 21 Aug 2020 22:30:46 +0000 Received: from EX13MTAUWC001.ant.amazon.com (iad55-ws-svc-p15-lb9-vlan2.iad.amazon.com [10.40.159.162]) by email-inbound-relay-1a-821c648d.us-east-1.amazon.com (Postfix) with ESMTPS id C2DE2A1FA1; Fri, 21 Aug 2020 22:30:39 +0000 (UTC) Received: from EX13D05UWC002.ant.amazon.com (10.43.162.92) by EX13MTAUWC001.ant.amazon.com (10.43.162.135) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Fri, 21 Aug 2020 22:30:11 +0000 Received: from EX13MTAUWC001.ant.amazon.com (10.43.162.135) by EX13D05UWC002.ant.amazon.com (10.43.162.92) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Fri, 21 Aug 2020 22:30:11 +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 15.0.1497.2 via Frontend Transport; Fri, 21 Aug 2020 22:30:11 +0000 Received: by dev-dsk-anchalag-2a-9c2d1d96.us-west-2.amazon.com (Postfix, from userid 4335130) id 59A8A40362; Fri, 21 Aug 2020 22:30:11 +0000 (UTC) Date: Fri, 21 Aug 2020 22:30:11 +0000 From: Anchal Agarwal To: , , , , , , , , , , , , , , , , , , , , , , , , , , , Subject: [PATCH v3 09/11] xen: Introduce wrapper for save/restore sched clock offset Message-ID: References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org 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 --- 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 91f5b330dcc6..e45349178ffc 100644 --- a/arch/x86/xen/time.c +++ b/arch/x86/xen/time.c @@ -387,12 +387,23 @@ 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; @@ -435,7 +446,7 @@ 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 9f0a4345220e..9a79e210119c 100644 --- a/arch/x86/xen/xen-ops.h +++ b/arch/x86/xen/xen-ops.h @@ -69,6 +69,8 @@ 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);