From patchwork Tue Nov 10 11:57:55 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Stabellini X-Patchwork-Id: 7589881 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id D463B9F2F7 for ; Tue, 10 Nov 2015 12:00:39 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id EF556207BA for ; Tue, 10 Nov 2015 12:00:38 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 09444207B7 for ; Tue, 10 Nov 2015 12:00:38 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Zw7ZQ-0006H5-Kl; Tue, 10 Nov 2015 11:58:40 +0000 Received: from smtp02.citrix.com ([66.165.176.63]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Zw7ZI-00062Y-HG for linux-arm-kernel@lists.infradead.org; Tue, 10 Nov 2015 11:58:34 +0000 X-IronPort-AV: E=Sophos;i="5.20,270,1444694400"; d="scan'208";a="317031492" From: Stefano Stabellini To: Subject: [PATCH v2 7/7] xen/arm: set the system time in Xen via the XENPF_settime64 hypercall Date: Tue, 10 Nov 2015 11:57:55 +0000 Message-ID: <1447156675-7418-7-git-send-email-stefano.stabellini@eu.citrix.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: References: MIME-Version: 1.0 X-DLP: MIA2 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20151110_035833_018251_4902FA01 X-CRM114-Status: GOOD ( 15.61 ) X-Spam-Score: -4.5 (----) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-kernel@vger.kernel.org, Ian.Campbell@citrix.com, linux-arm-kernel@lists.infradead.org, Stefano Stabellini Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP If Linux is running as dom0, call XENPF_settime64 to update the system time in Xen on pvclock_gtod notifications. Signed-off-by: Stefano Stabellini --- Changes in v2: - properly convert arch_timer ticker to nsec - rename dom0_op to platform_op - use timespec64 interfaces - use XENPF_settime64 --- arch/arm/xen/enlighten.c | 54 +++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 53 insertions(+), 1 deletion(-) diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index 32675b5..a991b25 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -28,6 +28,7 @@ #include #include #include +#include #include #include @@ -125,6 +126,52 @@ static void xen_read_wallclock(struct timespec64 *ts) } +static int xen_pvclock_gtod_notify(struct notifier_block *nb, + unsigned long was_set, void *priv) +{ + /* Protected by the calling core code serialization */ + static struct timespec64 next_sync; + + struct xen_platform_op op; + struct timespec64 now; + + now = __current_kernel_time64(); + + /* + * We only take the expensive HV call when the clock was set + * or when the 11 minutes RTC synchronization time elapsed. + */ + if (!was_set && timespec64_compare(&now, &next_sync) < 0) + return NOTIFY_OK; + + op.interface_version = XENPF_INTERFACE_VERSION; + op.cmd = XENPF_settime64; + op.u.settime64.mbz = 0; + op.u.settime64.secs = now.tv_sec; + op.u.settime64.nsecs = now.tv_nsec; + op.u.settime64.system_time = arch_timer_read_counter() * (u64)NSEC_PER_SEC; + do_div(op.u.settime64.system_time, arch_timer_get_rate()); + printk("GTOD: Setting to %llu.%u at %llu\n", + op.u.settime64.secs, + op.u.settime64.nsecs, + op.u.settime64.system_time); + (void)HYPERVISOR_platform_op(&op); + + /* + * Move the next drift compensation time 11 minutes + * ahead. That's emulating the sync_cmos_clock() update for + * the hardware RTC. + */ + next_sync = now; + next_sync.tv_sec += 11 * 60; + + return NOTIFY_OK; +} + +static struct notifier_block xen_pvclock_gtod_notifier = { + .notifier_call = xen_pvclock_gtod_notify, +}; + static void xen_percpu_init(void) { struct vcpu_register_vcpu_info info; @@ -323,7 +370,12 @@ static int __init xen_guest_init(void) pv_time_ops.steal_clock = xen_stolen_accounting; static_key_slow_inc(¶virt_steal_enabled); xen_read_wallclock(&ts); - do_settimeofday64(&ts); + if (xen_initial_domain()) + pvclock_gtod_register_notifier(&xen_pvclock_gtod_notifier); + else { + xen_read_wallclock(&ts); + do_settimeofday64(&ts); + } return 0; }