From patchwork Tue Jul 13 02:25:35 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zachary Amsden X-Patchwork-Id: 111627 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter.kernel.org (8.14.4/8.14.3) with ESMTP id o6D2Relp015169 for ; Tue, 13 Jul 2010 02:27:40 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756795Ab0GMC0T (ORCPT ); Mon, 12 Jul 2010 22:26:19 -0400 Received: from mx1.redhat.com ([209.132.183.28]:19462 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756478Ab0GMC0R (ORCPT ); Mon, 12 Jul 2010 22:26:17 -0400 Received: from int-mx05.intmail.prod.int.phx2.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.18]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o6D2QGU5001930 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Mon, 12 Jul 2010 22:26:16 -0400 Received: from mysore (vpn-10-168.rdu.redhat.com [10.11.10.168]) by int-mx05.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o6D2Pfik026035; Mon, 12 Jul 2010 22:26:14 -0400 From: Zachary Amsden To: KVM , Avi Kivity , Marcelo Tosatti , Glauber Costa Cc: Linux-kernel , Zachary Amsden , Avi Kivity , Marcelo Tosatti , Glauber Costa Subject: [PATCH 15/18] Implement getnsboottime kernel API Date: Mon, 12 Jul 2010 16:25:35 -1000 Message-Id: <1278987938-23873-16-git-send-email-zamsden@redhat.com> In-Reply-To: <1278987938-23873-1-git-send-email-zamsden@redhat.com> References: <1278987938-23873-1-git-send-email-zamsden@redhat.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.18 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter.kernel.org [140.211.167.41]); Tue, 13 Jul 2010 02:27:40 +0000 (UTC) diff --git a/include/linux/time.h b/include/linux/time.h index ea3559f..5d04108 100644 --- a/include/linux/time.h +++ b/include/linux/time.h @@ -145,6 +145,7 @@ extern void getnstimeofday(struct timespec *tv); extern void getrawmonotonic(struct timespec *ts); extern void getboottime(struct timespec *ts); extern void monotonic_to_bootbased(struct timespec *ts); +extern s64 getnsboottime(void); extern struct timespec timespec_trunc(struct timespec t, unsigned gran); extern int timekeeping_valid_for_hres(void); diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index caf8d4d..d250f0a 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -285,6 +285,33 @@ void ktime_get_ts(struct timespec *ts) } EXPORT_SYMBOL_GPL(ktime_get_ts); + +/** + * getnsboottime - get the bootbased clock in nsec format + * + * The function calculates the bootbased clock from the realtime + * clock and the wall_to_monotonic offset and stores the result + * in normalized timespec format in the variable pointed to by @ts. + */ +s64 getnsboottime(void) +{ + unsigned int seq; + s64 secs, nsecs; + + WARN_ON(timekeeping_suspended); + + do { + seq = read_seqbegin(&xtime_lock); + secs = xtime.tv_sec + wall_to_monotonic.tv_sec; + secs += total_sleep_time.tv_sec; + nsecs = xtime.tv_nsec + wall_to_monotonic.tv_nsec; + nsecs += total_sleep_time.tv_nsec + timekeeping_get_ns(); + + } while (read_seqretry(&xtime_lock, seq)); + return nsecs + (secs * NSEC_PER_SEC); +} +EXPORT_SYMBOL_GPL(getnsboottime); + /** * do_gettimeofday - Returns the time of day in a timeval * @tv: pointer to the timeval to be set