From patchwork Tue Jul 10 22:43:22 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: john stultz X-Patchwork-Id: 9939 Return-Path: X-Original-To: patchwork@peony.canonical.com Delivered-To: patchwork@peony.canonical.com Received: from fiordland.canonical.com (fiordland.canonical.com [91.189.94.145]) by peony.canonical.com (Postfix) with ESMTP id 9566823E57 for ; Tue, 10 Jul 2012 22:45:16 +0000 (UTC) Received: from mail-gh0-f180.google.com (mail-gh0-f180.google.com [209.85.160.180]) by fiordland.canonical.com (Postfix) with ESMTP id 49AAFA1819A for ; Tue, 10 Jul 2012 22:45:16 +0000 (UTC) Received: by ghbz12 with SMTP id z12so657363ghb.11 for ; Tue, 10 Jul 2012 15:45:05 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-forwarded-to:x-forwarded-for:delivered-to:received-spf:from:to:cc :subject:date:message-id:x-mailer:in-reply-to:references :x-content-scanned:x-cbid:x-gm-message-state; bh=TgBYwGnvPZaIrGSuZ6oNnzC2G/pXxs31GAzg9hivMMA=; b=VjZ98lx87ntH/dxHs7rrU0Jqm93Aq8Q54ApdpIcJOPhDQMmEKpbaQIOVJSGIwzZvBC 0ciPSaXQO6WCMKnOjUrTGPZju2nvPAOruoRxRB5XaQpZtS6D1i4h33Qm40W3LvJDpIey WuaJjRH+wGc4tGkG9gHh3TWdHrCxz7wuPwJThMKyGdhdHryl+dRYuj6fP60BFejz9t9f mARM3kle69DW/pM1gjlteR0mmZ/VeWSbaFMnSDbF5FuiHkNEg9/d6QZ+yW5vMEGuPGUk XNfwqMBcK0uKxf7xCAHXTHjhxFGQjI6add1vMMA6eh8ha1OHdvJZmzw2JwUkxs56u0P8 bz9A== Received: by 10.50.203.39 with SMTP id kn7mr12573277igc.53.1341960305511; Tue, 10 Jul 2012 15:45:05 -0700 (PDT) X-Forwarded-To: linaro-patchwork@canonical.com X-Forwarded-For: patch@linaro.org linaro-patchwork@canonical.com Delivered-To: patches@linaro.org Received: by 10.231.235.202 with SMTP id kh10csp1499ibb; Tue, 10 Jul 2012 15:45:05 -0700 (PDT) Received: by 10.50.178.102 with SMTP id cx6mr12903084igc.14.1341960305128; Tue, 10 Jul 2012 15:45:05 -0700 (PDT) Received: from e37.co.us.ibm.com (e37.co.us.ibm.com. 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Violators will be prosecuted; Tue, 10 Jul 2012 16:45:02 -0600 Received: from d03relay02.boulder.ibm.com (d03relay02.boulder.ibm.com [9.17.195.227]) by d03dlp03.boulder.ibm.com (Postfix) with ESMTP id 608B419D804E for ; Tue, 10 Jul 2012 22:44:35 +0000 (WET) Received: from d03av06.boulder.ibm.com (d03av06.boulder.ibm.com [9.17.195.245]) by d03relay02.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q6AMi0S4099392 for ; Tue, 10 Jul 2012 16:44:20 -0600 Received: from d03av06.boulder.ibm.com (loopback [127.0.0.1]) by d03av06.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q6AMiokq013633 for ; Tue, 10 Jul 2012 16:44:50 -0600 Received: from kernel.stglabs.ibm.com ([9.114.214.19]) by d03av06.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id q6AMiji5013399; Tue, 10 Jul 2012 16:44:49 -0600 From: John Stultz To: Linux Kernel Cc: Thomas Gleixner , Ingo Molnar , Peter Zijlstra , Prarit Bhargava , stable@vger.kernel.org, John Stultz Subject: [PATCH 4/6] hrtimer: Move lock held region in hrtimer_interrupt() Date: Tue, 10 Jul 2012 18:43:22 -0400 Message-Id: <1341960205-56738-5-git-send-email-johnstul@us.ibm.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1341960205-56738-1-git-send-email-johnstul@us.ibm.com> References: <1341960205-56738-1-git-send-email-johnstul@us.ibm.com> X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12071022-7408-0000-0000-000006A79CEA X-Gm-Message-State: ALoCoQliprSgvG5P83ZqItcaa7vXT/Pp6E31hm+mfRThMNyicjh3mEgGVPn/u7+QvSgtW48AsaDt From: Thomas Gleixner We need to update the base offsets from this code and we need to do that under base->lock. Move the lock held region around the ktime_get() calls. The ktime_get() calls are going to be replaced with a function which gets the time and the offsets atomically. CC: Ingo Molnar CC: Peter Zijlstra CC: Prarit Bhargava CC: Thomas Gleixner CC: stable@vger.kernel.org Signed-off-by: Thomas Gleixner Signed-off-by: John Stultz --- kernel/hrtimer.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index 7c20cb8..14a260a 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -1263,11 +1263,10 @@ void hrtimer_interrupt(struct clock_event_device *dev) cpu_base->nr_events++; dev->next_event.tv64 = KTIME_MAX; + raw_spin_lock(&cpu_base->lock); entry_time = now = ktime_get(); retry: expires_next.tv64 = KTIME_MAX; - - raw_spin_lock(&cpu_base->lock); /* * We set expires_next to KTIME_MAX here with cpu_base->lock * held to prevent that a timer is enqueued in our queue via @@ -1344,6 +1343,7 @@ retry: * interrupt routine. We give it 3 attempts to avoid * overreacting on some spurious event. */ + raw_spin_lock(&cpu_base->lock); now = ktime_get(); cpu_base->nr_retries++; if (++retries < 3) @@ -1356,6 +1356,7 @@ retry: */ cpu_base->nr_hangs++; cpu_base->hang_detected = 1; + raw_spin_unlock(&cpu_base->lock); delta = ktime_sub(now, entry_time); if (delta.tv64 > cpu_base->max_hang_time.tv64) cpu_base->max_hang_time = delta;