From patchwork Wed Nov 11 16:51:36 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Stabellini X-Patchwork-Id: 7596821 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 43CE39F2F7 for ; Wed, 11 Nov 2015 16:54:22 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 637642066E for ; Wed, 11 Nov 2015 16:54:21 +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 75DF620667 for ; Wed, 11 Nov 2015 16:54:20 +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 1ZwYdH-0004h6-9l; Wed, 11 Nov 2015 16:52:27 +0000 Received: from smtp.citrix.com ([66.165.176.89]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZwYd4-0004XD-6C for linux-arm-kernel@lists.infradead.org; Wed, 11 Nov 2015 16:52:15 +0000 X-IronPort-AV: E=Sophos;i="5.20,276,1444694400"; d="scan'208";a="311606429" From: Stefano Stabellini To: Subject: [PATCH v3 6/6] xen/arm: set the system time in Xen via the XENPF_settime64 hypercall Date: Wed, 11 Nov 2015 16:51:36 +0000 Message-ID: <1447260696-450-6-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: MIA1 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20151111_085214_445519_721D1EA7 X-CRM114-Status: GOOD ( 14.80 ) X-Spam-Score: -7.3 (-------) 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 Acked-by: Arnd Bergmann --- Changes in v3: - s/%llu.%0u/%llu.%09u - in xen_pvclock_gtod_notify use the passed struct timekeeper pointer rather than calling __current_kernel_time64 - use the passed struct timekeeper pointer to get the system time too 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 | 55 +++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 54 insertions(+), 1 deletion(-) diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index eede8e9..9b4bc54 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -28,7 +28,10 @@ #include #include #include +#include +#include #include +#include #include @@ -120,6 +123,54 @@ static void xen_read_wallclock(struct timespec64 *ts) *ts = ns_to_timespec64(delta); } +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, system_time; + struct timekeeper *tk = priv; + + now.tv_sec = tk->xtime_sec; + now.tv_nsec = (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift); + system_time = timespec64_add(now, tk->wall_to_monotonic); + + /* + * 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 = timespec64_to_ns(&system_time); + printk("GTOD: Setting to %llu.%09u 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; @@ -316,7 +367,9 @@ static int __init xen_guest_init(void) pv_time_ops.steal_clock = xen_stolen_accounting; static_key_slow_inc(¶virt_steal_enabled); - + if (xen_initial_domain()) + pvclock_gtod_register_notifier(&xen_pvclock_gtod_notifier); + return 0; } early_initcall(xen_guest_init);