[PATCH] Don't disable irqs in set_next_event and set_mode callbacks

Uwe Kleine-König
2009-09-21T07:39:22Z

These functions are called with irqs already off.

at91rm2000 had a WARN_ON_ONCE if irqs were enabled since Nov 2008 with
noone reporting having hit it.

It should be safe to remove now.

Signed-off-by: Uwe Kleine-K?nig <u.kleine-koenig@pengutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Alessandro Rubini <rubini@unipv.it>
Cc: Andrea Gallo <andrea.gallo@stericsson.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric Miao <eric.miao@marvell.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Kristoffer Ericson <Kristoffer.Ericson@gmail.com>
Cc: Magnus Damm <damm@igel.co.jp>
Cc: Nicolas Pitre <nico@marvell.com>
Cc: Remy Bohmer <linux@bohmer.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
---
Hello,

should I split the patch? Would you prefer to add a WARN_ON_ONCE for
some time (as at91rm9200 had it)?

Best regards
Uwe

arch/arm/mach-at91/at91rm9200_time.c | 14 --------------
arch/arm/mach-at91/at91sam926x_time.c | 6 +-----
arch/arm/mach-nomadik/timer.c | 9 +--------
arch/arm/mach-pxa/time.c | 10 +---------
arch/arm/mach-sa1100/time.c | 8 +-------
5 files changed, 4 insertions(+), 43 deletions(-)

diff --git a/arch/arm/mach-at91/at91rm9200_time.c b/arch/arm/mach-at91/at91rm9200_time.c
index 309f351..f27ccf6 100644
--- a/arch/arm/mach-at91/at91rm9200_time.c
+++ b/arch/arm/mach-at91/at91rm9200_time.c
@@ -132,24 +132,11 @@ clkevt32k_mode(enum clock_event_mode mode, struct clock_event_device *dev)
static int
clkevt32k_next_event(unsigned long delta, struct clock_event_device *dev)
{
- unsigned long flags;
u32 alm;
int status = 0;

BUG_ON(delta < 2);

- /* Use "raw" primitives so we behave correctly on RT kernels. */
- raw_local_irq_save(flags);
-
- /*
- * According to Thomas Gleixner irqs are already disabled here. Simply
- * removing raw_local_irq_save above (and the matching
- * raw_local_irq_restore) was not accepted. See
- * http://thread.gmane.org/gmane.linux.ports.arm.kernel/41174
- * So for now (2008-11-20) just warn once if irqs were not disabled ...
- */
- WARN_ON_ONCE(!raw_irqs_disabled_flags(flags));
-
/* The alarm IRQ uses absolute time (now+delta), not the relative
* time (delta) in our calling convention. Like all clockevents
* using such "match" hardware, we have a race to defend against.
@@ -169,7 +156,6 @@ clkevt32k_next_event(unsigned long delta, struct clock_event_device *dev)
alm += delta;
at91_sys_write(AT91_ST_RTAR, alm);

- raw_local_irq_restore(flags);
return status;
}

diff --git a/arch/arm/mach-at91/at91sam926x_time.c b/arch/arm/mach-at91/at91sam926x_time.c
index 4bd56ae..c26cd6e 100644
--- a/arch/arm/mach-at91/at91sam926x_time.c
+++ b/arch/arm/mach-at91/at91sam926x_time.c
@@ -62,16 +62,12 @@ static struct clocksource pit_clk = {
static void
pit_clkevt_mode(enum clock_event_mode mode, struct clock_event_device *dev)
{
- unsigned long flags;
-
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
- /* update clocksource counter, then enable the IRQ */
- raw_local_irq_save(flags);
+ /* update clocksource counter */
pit_cnt += pit_cycle * PIT_PICNT(at91_sys_read(AT91_PIT_PIVR));
at91_sys_write(AT91_PIT_MR, (pit_cycle - 1) | AT91_PIT_PITEN
| AT91_PIT_PITIEN);
- raw_local_irq_restore(flags);
break;
case CLOCK_EVT_MODE_ONESHOT:
BUG();
diff --git a/arch/arm/mach-nomadik/timer.c b/arch/arm/mach-nomadik/timer.c
index d1738e7..e361be6 100644
--- a/arch/arm/mach-nomadik/timer.c
+++ b/arch/arm/mach-nomadik/timer.c
@@ -54,24 +54,17 @@ static struct clocksource nmdk_clksrc = {
static void nmdk_clkevt_mode(enum clock_event_mode mode,
struct clock_event_device *dev)
{
- unsigned long flags;
-
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
- /* enable interrupts -- and count current value? */
- raw_local_irq_save(flags);
+ /* count current value? */
writel(readl(mtu_base + MTU_IMSC) | 1, mtu_base + MTU_IMSC);
- raw_local_irq_restore(flags);
break;
case CLOCK_EVT_MODE_ONESHOT:
BUG(); /* Not supported, yet */
/* FALLTHROUGH */
case CLOCK_EVT_MODE_SHUTDOWN:
case CLOCK_EVT_MODE_UNUSED:
- /* disable irq */
- raw_local_irq_save(flags);
writel(readl(mtu_base + MTU_IMSC) & ~1, mtu_base + MTU_IMSC);
- raw_local_irq_restore(flags);
break;
case CLOCK_EVT_MODE_RESUME:
break;
diff --git a/arch/arm/mach-pxa/time.c b/arch/arm/mach-pxa/time.c
index 750c448..293e40a 100644
--- a/arch/arm/mach-pxa/time.c
+++ b/arch/arm/mach-pxa/time.c
@@ -76,14 +76,12 @@ pxa_ost0_interrupt(int irq, void *dev_id)
static int
pxa_osmr0_set_next_event(unsigned long delta, struct clock_event_device *dev)
{
- unsigned long flags, next, oscr;
+ unsigned long next, oscr;

- raw_local_irq_save(flags);
OIER |= OIER_E0;
next = OSCR + delta;
OSMR0 = next;
oscr = OSCR;
- raw_local_irq_restore(flags);

return (signed)(next - oscr) <= MIN_OSCR_DELTA ? -ETIME : 0;
}
@@ -91,23 +89,17 @@ pxa_osmr0_set_next_event(unsigned long delta, struct clock_event_device *dev)
static void
pxa_osmr0_set_mode(enum clock_event_mode mode, struct clock_event_device *dev)
{
- unsigned long irqflags;
-
switch (mode) {
case CLOCK_EVT_MODE_ONESHOT:
- raw_local_irq_save(irqflags);
OIER &= ~OIER_E0;
OSSR = OSSR_M0;
- raw_local_irq_restore(irqflags);
break;

case CLOCK_EVT_MODE_UNUSED:
case CLOCK_EVT_MODE_SHUTDOWN:
/* initializing, released, or preparing for suspend */
- raw_local_irq_save(irqflags);
OIER &= ~OIER_E0;
OSSR = OSSR_M0;
- raw_local_irq_restore(irqflags);
break;

case CLOCK_EVT_MODE_RESUME:
diff --git a/arch/arm/mach-sa1100/time.c b/arch/arm/mach-sa1100/time.c
index 95d92e8..a7a6091 100644
--- a/arch/arm/mach-sa1100/time.c
+++ b/arch/arm/mach-sa1100/time.c
@@ -35,14 +35,12 @@ static irqreturn_t sa1100_ost0_interrupt(int irq, void *dev_id)
static int
sa1100_osmr0_set_next_event(unsigned long delta, struct clock_event_device *c)
{
- unsigned long flags, next, oscr;
+ unsigned long next, oscr;

- raw_local_irq_save(flags);
OIER |= OIER_E0;
next = OSCR + delta;
OSMR0 = next;
oscr = OSCR;
- raw_local_irq_restore(flags);

return (signed)(next - oscr) <= MIN_OSCR_DELTA ? -ETIME : 0;
}
@@ -50,16 +48,12 @@ sa1100_osmr0_set_next_event(unsigned long delta, struct clock_event_device *c)
static void
sa1100_osmr0_set_mode(enum clock_event_mode mode, struct clock_event_device *c)
{
- unsigned long flags;
-
switch (mode) {
case CLOCK_EVT_MODE_ONESHOT:
case CLOCK_EVT_MODE_UNUSED:
case CLOCK_EVT_MODE_SHUTDOWN:
- raw_local_irq_save(flags);
OIER &= ~OIER_E0;
OSSR = OSSR_M0;
- raw_local_irq_restore(flags);
break;

case CLOCK_EVT_MODE_RESUME:
--
1.6.4.3