From: Linus Walleij Date: Mon, 29 Oct 2012 14:24:18 +0000 (+0100) Subject: clocksource: arm_generic: use integer math helpers X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=980097b36074596c76c1367a9e7b70ec8583d55b;p=openwrt%2Fstaging%2Fblogic.git clocksource: arm_generic: use integer math helpers This will make the two crucial integer divisions in the generic ARM arch timer used for ARMv8 use the kernel DIV_ROUND_CLOSEST() helper inline from so they get more precise. Cc: Marc Zyngier Cc: Catalin Marinas Signed-off-by: Linus Walleij Signed-off-by: John Stultz --- diff --git a/drivers/clocksource/arm_generic.c b/drivers/clocksource/arm_generic.c index c4d9f9566c64..6cd1b30e01ab 100644 --- a/drivers/clocksource/arm_generic.c +++ b/drivers/clocksource/arm_generic.c @@ -127,7 +127,7 @@ static void __init arch_timer_calibrate(void) /* Cache the sched_clock multiplier to save a divide in the hot path. */ - sched_clock_mult = NSEC_PER_SEC / arch_timer_rate; + sched_clock_mult = DIV_ROUND_CLOSEST(NSEC_PER_SEC, arch_timer_rate); pr_info("Architected local timer running at %u.%02uMHz.\n", arch_timer_rate / 1000000, (arch_timer_rate / 10000) % 100); @@ -221,7 +221,7 @@ int __init arm_generic_timer_init(void) clocksource_register_hz(&clocksource_counter, arch_timer_rate); /* Calibrate the delay loop directly */ - lpj_fine = arch_timer_rate / HZ; + lpj_fine = DIV_ROUND_CLOSEST(arch_timer_rate, HZ); /* Immediately configure the timer on the boot CPU */ arch_timer_setup(per_cpu_ptr(&arch_timer_evt, smp_processor_id()));