diff options
| author | Stephen Boyd <sboyd@codeaurora.org> | 2013-07-18 16:21:18 -0700 |
|---|---|---|
| committer | John Stultz <john.stultz@linaro.org> | 2013-10-09 16:54:10 -0700 |
| commit | 65cd4f6c99c1170bd0114dbd71b978012ea44d28 (patch) | |
| tree | fbde89149eb5032b49875cddf728d598ffd349ad /arch | |
| parent | 07783397c6e3757de805bda5e1139a9e47aa7d74 (diff) | |
arch_timer: Move to generic sched_clock framework
Register with the generic sched_clock framework now that it
supports 64 bits. This fixes two problems with the current
sched_clock support for machines using the architected 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 without this patch. Finally, it
allows us to move the sched_clock setup into drivers clocksource
out of the arch ports.
Cc: Christopher Covington <cov@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm/kernel/arch_timer.c | 14 | ||||
| -rw-r--r-- | arch/arm64/Kconfig | 1 | ||||
| -rw-r--r-- | arch/arm64/kernel/time.c | 10 |
3 files changed, 1 insertions, 24 deletions
diff --git a/arch/arm/kernel/arch_timer.c b/arch/arm/kernel/arch_timer.c index 221f07b11ccb..1791f12c180b 100644 --- a/arch/arm/kernel/arch_timer.c +++ b/arch/arm/kernel/arch_timer.c @@ -11,7 +11,6 @@ #include <linux/init.h> #include <linux/types.h> #include <linux/errno.h> -#include <linux/sched_clock.h> #include <asm/delay.h> @@ -22,13 +21,6 @@ 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 +40,5 @@ 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); - return 0; } diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index c04454876bcb..35fd0eb57270 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -14,6 +14,7 @@ config ARM64 select GENERIC_IOMAP select GENERIC_IRQ_PROBE select GENERIC_IRQ_SHOW + select GENERIC_SCHED_CLOCK select GENERIC_SMP_IDLE_THREAD select GENERIC_TIME_VSYSCALL select HARDIRQS_SW_RESEND diff --git a/arch/arm64/kernel/time.c b/arch/arm64/kernel/time.c index 03dc3718eb13..29c39d5d77e3 100644 --- a/arch/arm64/kernel/time.c +++ b/arch/arm64/kernel/time.c @@ -61,13 +61,6 @@ unsigned long profile_pc(struct pt_regs *regs) EXPORT_SYMBOL(profile_pc); #endif -static u64 sched_clock_mult __read_mostly; - -unsigned long long notrace sched_clock(void) -{ - return arch_timer_read_counter() * sched_clock_mult; -} - void __init time_init(void) { u32 arch_timer_rate; @@ -78,9 +71,6 @@ void __init time_init(void) if (!arch_timer_rate) panic("Unable to initialise architected timer.\n"); - /* Cache the sched_clock multiplier to save a divide in the hot path. */ - sched_clock_mult = NSEC_PER_SEC / arch_timer_rate; - /* Calibrate the delay loop directly */ lpj_fine = arch_timer_rate / HZ; } |