Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965392Ab3DTA3h (ORCPT ); Fri, 19 Apr 2013 20:29:37 -0400 Received: from wolverine02.qualcomm.com ([199.106.114.251]:47892 "EHLO wolverine02.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965218Ab3DTA3K (ORCPT ); Fri, 19 Apr 2013 20:29:10 -0400 X-IronPort-AV: E=Sophos;i="4.87,512,1363158000"; d="scan'208";a="40095503" From: Stephen Boyd To: Rob Herring Cc: linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Russell King , arm@kernel.org, Catalin Marinas , Will Deacon , John Stultz , Thomas Gleixner Subject: [PATCH 4/4] ARM: arch_timer: Move to setup_sched_clock_64() Date: Fri, 19 Apr 2013 17:29:06 -0700 Message-Id: <1366417746-24990-5-git-send-email-sboyd@codeaurora.org> X-Mailer: git-send-email 1.8.2.1.392.g85e7e81 In-Reply-To: <1366417746-24990-1-git-send-email-sboyd@codeaurora.org> References: <1366417746-24990-1-git-send-email-sboyd@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3259 Lines: 85 Register with the ARM sched_clock framework now that it supports 64 bits. This also fixes two problems with the current sched_clock support for machines using the archited timers. First off, we don't subtract the start value from subsequent sched_clock calls so we can potentially start off with sched_clock returning gigantic numbers. Second, there is no support for suspend/resume handling so problems such as discussed in 6a4dae5 (ARM: 7565/1: sched: stop sched_clock() during suspend, 2012-10-23) can happen. Signed-off-by: Stephen Boyd --- arch/arm/include/asm/sched_clock.h | 3 --- arch/arm/kernel/arch_timer.c | 14 ++------------ arch/arm/kernel/sched_clock.c | 3 ++- 3 files changed, 4 insertions(+), 16 deletions(-) diff --git a/arch/arm/include/asm/sched_clock.h b/arch/arm/include/asm/sched_clock.h index 7fcd2ee..e6f765a 100644 --- a/arch/arm/include/asm/sched_clock.h +++ b/arch/arm/include/asm/sched_clock.h @@ -10,9 +10,6 @@ extern void sched_clock_postinit(void); extern void setup_sched_clock(u32 (*read)(void), int bits, unsigned long rate); - -extern unsigned long long (*sched_clock_func)(void); - extern void setup_sched_clock_64(u64 (*read)(void), int bits, unsigned long rate); #endif diff --git a/arch/arm/kernel/arch_timer.c b/arch/arm/kernel/arch_timer.c index 59dcdce..b45250b 100644 --- a/arch/arm/kernel/arch_timer.c +++ b/arch/arm/kernel/arch_timer.c @@ -22,13 +22,6 @@ static unsigned long arch_timer_read_counter_long(void) return arch_timer_read_counter(); } -static u32 sched_clock_mult __read_mostly; - -static unsigned long long notrace arch_timer_sched_clock(void) -{ - return arch_timer_read_counter() * sched_clock_mult; -} - static struct delay_timer arch_delay_timer; static void __init arch_timer_delay_timer_register(void) @@ -48,11 +41,8 @@ int __init arch_timer_arch_init(void) arch_timer_delay_timer_register(); - /* Cache the sched_clock multiplier to save a divide in the hot path. */ - sched_clock_mult = NSEC_PER_SEC / arch_timer_rate; - sched_clock_func = arch_timer_sched_clock; - pr_info("sched_clock: ARM arch timer >56 bits at %ukHz, resolution %uns\n", - arch_timer_rate / 1000, sched_clock_mult); + /* 56 bits minimum, so we assume worst case rollover */ + setup_sched_clock_64(arch_timer_read_counter, 56, arch_timer_rate); return 0; } diff --git a/arch/arm/kernel/sched_clock.c b/arch/arm/kernel/sched_clock.c index 7875e9e..b6067d8 100644 --- a/arch/arm/kernel/sched_clock.c +++ b/arch/arm/kernel/sched_clock.c @@ -181,7 +181,8 @@ static unsigned long long notrace sched_clock_32(void) return cyc_to_sched_clock(cyc, sched_clock_mask); } -unsigned long long __read_mostly (*sched_clock_func)(void) = sched_clock_32; +static unsigned long long __read_mostly +(*sched_clock_func)(void) = sched_clock_32; static unsigned long long notrace sched_clock_64(void) { -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by The Linux Foundation -- 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/