Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753245Ab2BTLra (ORCPT ); Mon, 20 Feb 2012 06:47:30 -0500 Received: from terminus.zytor.com ([198.137.202.10]:33332 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752687Ab2BTLr3 (ORCPT ); Mon, 20 Feb 2012 06:47:29 -0500 Date: Mon, 20 Feb 2012 03:46:19 -0800 From: tip-bot for Dimitri Sivanich Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, steiner@sgi.com, johnstul@us.ibm.com, tglx@linutronix.de, sivanich@sgi.com, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, johnstul@us.ibm.com, steiner@sgi.com, tglx@linutronix.de, sivanich@sgi.com, mingo@elte.hu In-Reply-To: <20120217141641.GA28063@sgi.com> References: <20120217141641.GA28063@sgi.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/uv] x86/UV: Lower UV rtc clocksource rating Git-Commit-ID: b0deca2e0270135f797e81bdb0743e50fd1dc58d X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.6 (terminus.zytor.com [127.0.0.1]); Mon, 20 Feb 2012 03:46:48 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2067 Lines: 55 Commit-ID: b0deca2e0270135f797e81bdb0743e50fd1dc58d Gitweb: http://git.kernel.org/tip/b0deca2e0270135f797e81bdb0743e50fd1dc58d Author: Dimitri Sivanich AuthorDate: Fri, 17 Feb 2012 08:16:41 -0600 Committer: Ingo Molnar CommitDate: Mon, 20 Feb 2012 09:07:56 +0100 x86/UV: Lower UV rtc clocksource rating Lower the rating of the UV rtc clocksource to just below that of the tsc, to improve performance. Reading the tsc clocksource has lower latency than reading the rtc, so favor it in situations where it is synchronized and stable. When the tsc is unsynchronized, the rtc needs to be the chosen clocksource. Signed-off-by: Dimitri Sivanich Cc: John Stultz Cc: Jack Steiner Link: http://lkml.kernel.org/r/20120217141641.GA28063@sgi.com Signed-off-by: Ingo Molnar --- arch/x86/platform/uv/uv_time.c | 6 +----- 1 files changed, 1 insertions(+), 5 deletions(-) diff --git a/arch/x86/platform/uv/uv_time.c b/arch/x86/platform/uv/uv_time.c index 9f29a01..5032e0d 100644 --- a/arch/x86/platform/uv/uv_time.c +++ b/arch/x86/platform/uv/uv_time.c @@ -37,7 +37,7 @@ static void uv_rtc_timer_setup(enum clock_event_mode, static struct clocksource clocksource_uv = { .name = RTC_NAME, - .rating = 400, + .rating = 299, .read = uv_read_rtc, .mask = (cycle_t)UVH_RTC_REAL_TIME_CLOCK_MASK, .flags = CLOCK_SOURCE_IS_CONTINUOUS, @@ -379,10 +379,6 @@ static __init int uv_rtc_setup_clock(void) if (!is_uv_system()) return -ENODEV; - /* If single blade, prefer tsc */ - if (uv_num_possible_blades() == 1) - clocksource_uv.rating = 250; - rc = clocksource_register_hz(&clocksource_uv, sn_rtc_cycles_per_second); if (rc) printk(KERN_INFO "UV RTC clocksource failed rc %d\n", rc); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/