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authorLinus Torvalds <torvalds@linux-foundation.org>2015-03-28 19:21:23 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2015-03-28 19:21:23 +0100
commit4a89452e70a019cb6bfb1114b12f2607c3bace24 (patch)
tree4744009041b3fb9d2b78621d2f6ab42c01b1cb3a
parentMerge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/k... (diff)
parentclocksource/drivers/sun5i: Fix cpufreq interaction with sched_clock() (diff)
downloadlinux-4a89452e70a019cb6bfb1114b12f2607c3bace24.tar.xz
linux-4a89452e70a019cb6bfb1114b12f2607c3bace24.zip
Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Ingo Molnar: "Two clocksource driver fixes, and an idle loop RCU warning fix" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clocksource/drivers/sun5i: Fix cpufreq interaction with sched_clock() clocksource/drivers: Fix various !CONFIG_HAS_IOMEM build errors timers/tick/broadcast-hrtimer: Fix suspicious RCU usage in idle loop
-rw-r--r--drivers/clocksource/Kconfig3
-rw-r--r--drivers/clocksource/timer-sun5i.c7
-rw-r--r--kernel/time/tick-broadcast-hrtimer.c11
3 files changed, 12 insertions, 9 deletions
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 68161f7a07d6..a0b036ccb118 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -192,6 +192,7 @@ config SYS_SUPPORTS_EM_STI
config SH_TIMER_CMT
bool "Renesas CMT timer driver" if COMPILE_TEST
depends on GENERIC_CLOCKEVENTS
+ depends on HAS_IOMEM
default SYS_SUPPORTS_SH_CMT
help
This enables build of a clocksource and clockevent driver for
@@ -201,6 +202,7 @@ config SH_TIMER_CMT
config SH_TIMER_MTU2
bool "Renesas MTU2 timer driver" if COMPILE_TEST
depends on GENERIC_CLOCKEVENTS
+ depends on HAS_IOMEM
default SYS_SUPPORTS_SH_MTU2
help
This enables build of a clockevent driver for the Multi-Function
@@ -210,6 +212,7 @@ config SH_TIMER_MTU2
config SH_TIMER_TMU
bool "Renesas TMU timer driver" if COMPILE_TEST
depends on GENERIC_CLOCKEVENTS
+ depends on HAS_IOMEM
default SYS_SUPPORTS_SH_TMU
help
This enables build of a clocksource and clockevent driver for
diff --git a/drivers/clocksource/timer-sun5i.c b/drivers/clocksource/timer-sun5i.c
index 5dcbf90b8015..58597fbcc046 100644
--- a/drivers/clocksource/timer-sun5i.c
+++ b/drivers/clocksource/timer-sun5i.c
@@ -17,7 +17,6 @@
#include <linux/irq.h>
#include <linux/irqreturn.h>
#include <linux/reset.h>
-#include <linux/sched_clock.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
@@ -137,11 +136,6 @@ static struct irqaction sun5i_timer_irq = {
.dev_id = &sun5i_clockevent,
};
-static u64 sun5i_timer_sched_read(void)
-{
- return ~readl(timer_base + TIMER_CNTVAL_LO_REG(1));
-}
-
static void __init sun5i_timer_init(struct device_node *node)
{
struct reset_control *rstc;
@@ -172,7 +166,6 @@ static void __init sun5i_timer_init(struct device_node *node)
writel(TIMER_CTL_ENABLE | TIMER_CTL_RELOAD,
timer_base + TIMER_CTL_REG(1));
- sched_clock_register(sun5i_timer_sched_read, 32, rate);
clocksource_mmio_init(timer_base + TIMER_CNTVAL_LO_REG(1), node->name,
rate, 340, 32, clocksource_mmio_readl_down);
diff --git a/kernel/time/tick-broadcast-hrtimer.c b/kernel/time/tick-broadcast-hrtimer.c
index eb682d5c697c..6aac4beedbbe 100644
--- a/kernel/time/tick-broadcast-hrtimer.c
+++ b/kernel/time/tick-broadcast-hrtimer.c
@@ -49,6 +49,7 @@ static void bc_set_mode(enum clock_event_mode mode,
*/
static int bc_set_next(ktime_t expires, struct clock_event_device *bc)
{
+ int bc_moved;
/*
* We try to cancel the timer first. If the callback is on
* flight on some other cpu then we let it handle it. If we
@@ -60,9 +61,15 @@ static int bc_set_next(ktime_t expires, struct clock_event_device *bc)
* restart the timer because we are in the callback, but we
* can set the expiry time and let the callback return
* HRTIMER_RESTART.
+ *
+ * Since we are in the idle loop at this point and because
+ * hrtimer_{start/cancel} functions call into tracing,
+ * calls to these functions must be bound within RCU_NONIDLE.
*/
- if (hrtimer_try_to_cancel(&bctimer) >= 0) {
- hrtimer_start(&bctimer, expires, HRTIMER_MODE_ABS_PINNED);
+ RCU_NONIDLE(bc_moved = (hrtimer_try_to_cancel(&bctimer) >= 0) ?
+ !hrtimer_start(&bctimer, expires, HRTIMER_MODE_ABS_PINNED) :
+ 0);
+ if (bc_moved) {
/* Bind the "device" to the cpu */
bc->bound_on = smp_processor_id();
} else if (bc->bound_on == smp_processor_id()) {