From patchwork Mon Jul 22 10:33:28 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 169362 Delivered-To: patch@linaro.org Received: by 2002:a92:4782:0:0:0:0:0 with SMTP id e2csp7351125ilk; Mon, 22 Jul 2019 03:33:46 -0700 (PDT) X-Google-Smtp-Source: APXvYqykgk8Rw7zyUvsACr0QP7gmJXuvPLl4KWBp+UbkZBfrHl/tdqBW2026hlJAa+AJsJP3rCsW X-Received: by 2002:a17:902:2ac8:: with SMTP id j66mr71227622plb.273.1563791626116; Mon, 22 Jul 2019 03:33:46 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1563791626; cv=none; d=google.com; s=arc-20160816; b=KGXurJqI50g30ZrOHSOiyep54k2/L5v9f427mN0tNcKot71ZUuifrwIhsc+aGqtQ48 ENpb9RNRIUTD5Nu0M4KfQ7BdFl1D8E1bjyq97cJxeZvTb62hDB93SOp2cFHQPV0dal74 18gdz1M3Xz4bZxLnHOk3ne+ExuKoBZOyOO0G7AE1zq1x4NpcXjKQJV2o9nnPuIGWRXCw Uh2aEFHt8TTQvczvE/5Wc+7YwpiC8AObpBVIHcx8YmX6Dzken8AUxYJ0U8hrN1XU/3lO +kIL+dEF2uTXe2Lgh4G4/wSKHFytqVMGROXUJD0rVVOp4OS4QuudKzAcPzxVsJMFgu/7 7BwA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=zt4uy8sPVoJl+6lAqJHyKxtG25XWFS27z1X2lfAr8NY=; b=J2gDnV4mzgK8L49dDtea458p8wpJLQONJzk26gGrRrxN/fJKDzxzW/Y+RZhF3PrKwj a6y6LnCbXcrEXIoFZtT+lgGlKLpcg5s1MXgiNuCzEGllY/f7JhZhp6A2udLVC0LIB6dF Q6cx8FsPJ27aHlmfCrFZZixlG6JC3xVtkW8ff2gSag8Pf5w+9NZ2lJkkEEbVKw0el/W8 t1IT13yYZS/7A5Yc3mXKnwfkiStjDlIZJlT0Q+XO8xeTdLQv+qSYV4GE6ue2pzIGVgn3 7FG1U4dy9Bl8H15MEfZJZKJ8XoXxzyxS+/D1jCxZQBPKuB85NVNUolcWKqrdyuvrvxP2 4OiQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id i71si7884479pge.3.2019.07.22.03.33.45; Mon, 22 Jul 2019 03:33:46 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729634AbfGVKdo (ORCPT + 29 others); Mon, 22 Jul 2019 06:33:44 -0400 Received: from foss.arm.com ([217.140.110.172]:35420 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726120AbfGVKdm (ORCPT ); Mon, 22 Jul 2019 06:33:42 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 3E68D1509; Mon, 22 Jul 2019 03:33:42 -0700 (PDT) Received: from filthy-habits.cambridge.arm.com (filthy-habits.cambridge.arm.com [10.1.197.61]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C32B53F71A; Mon, 22 Jul 2019 03:33:40 -0700 (PDT) From: Marc Zyngier To: Thomas Gleixner , John Stultz , Pavel Tatashin , Petr Mladek , Sergey Senozhatsky , Steven Rostedt , Will Deacon , Catalin Marinas , Mark Rutland Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/3] printk: Allow architecture-specific timestamping function Date: Mon, 22 Jul 2019 11:33:28 +0100 Message-Id: <20190722103330.255312-2-marc.zyngier@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190722103330.255312-1-marc.zyngier@arm.com> References: <20190722103330.255312-1-marc.zyngier@arm.com> MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org printk currently relies on local_clock to time-stamp the kernel messages. In order to allow the timestamping (and only that) to be overridden by architecture-specific code, let's declare a new timestamp_clock() function, which gets used by the printk code. Architectures willing to make use of this facility will have to define CONFIG_ARCH_HAS_TIMESTAMP_CLOCK. The default is of course to return local_clock(), so that the existing behaviour stays unchanged. Signed-off-by: Marc Zyngier --- include/linux/sched/clock.h | 13 +++++++++++++ kernel/printk/printk.c | 4 ++-- 2 files changed, 15 insertions(+), 2 deletions(-) -- 2.20.1 diff --git a/include/linux/sched/clock.h b/include/linux/sched/clock.h index 867d588314e0..3cf4b2a8ce18 100644 --- a/include/linux/sched/clock.h +++ b/include/linux/sched/clock.h @@ -98,4 +98,17 @@ static inline void enable_sched_clock_irqtime(void) {} static inline void disable_sched_clock_irqtime(void) {} #endif +#ifdef CONFIG_ARCH_HAS_TIMESTAMP_CLOCK +/* Special need architectures can provide their timestamping function */ +extern u64 timestamp_clock(void); + +#else + +static inline u64 timestamp_clock(void) +{ + return local_clock(); +} + +#endif + #endif /* _LINUX_SCHED_CLOCK_H */ diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 1888f6a3b694..166702316714 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -638,7 +638,7 @@ static int log_store(u32 caller_id, int facility, int level, if (ts_nsec > 0) msg->ts_nsec = ts_nsec; else - msg->ts_nsec = local_clock(); + msg->ts_nsec = timestamp_clock(); #ifdef CONFIG_PRINTK_CALLER msg->caller_id = caller_id; #endif @@ -1841,7 +1841,7 @@ static bool cont_add(u32 caller_id, int facility, int level, cont.facility = facility; cont.level = level; cont.caller_id = caller_id; - cont.ts_nsec = local_clock(); + cont.ts_nsec = timestamp_clock(); cont.flags = flags; }