[PATCH] add suspend/resume for timer
From: Shaohua Li
Date: Wed Jun 22 2005 - 22:02:18 EST
Hi,
The timers lack .suspend/.resume methods. Because of this, jiffies got a
big compensation after a S3 resume. And then softlockup watchdog reports
an oops. This occured with HPET enabled, but it's also possible for
other timers.
I know Linux will introduce a new timer core system, but it maybe take a
long time, so I send this patch to fix bugs at hand. If the new timer
system will be merged soon, please ignore this one.
Thanks,
Shaohua
Signed-off-by: Shaohua Li<shaohua.li@xxxxxxxxx>
---
linux-2.6.12-mm1-root/arch/i386/kernel/time.c | 10 ++++
linux-2.6.12-mm1-root/arch/i386/kernel/timers/timer_hpet.c | 14 ++++++
linux-2.6.12-mm1-root/arch/i386/kernel/timers/timer_pit.c | 27 -------------
linux-2.6.12-mm1-root/arch/i386/kernel/timers/timer_pm.c | 9 ++++
linux-2.6.12-mm1-root/arch/i386/kernel/timers/timer_tsc.c | 14 ++++++
linux-2.6.12-mm1-root/include/asm-i386/timer.h | 3 +
6 files changed, 50 insertions(+), 27 deletions(-)
diff -puN include/asm-i386/timer.h~last_tick_fix include/asm-i386/timer.h
--- linux-2.6.12-mm1/include/asm-i386/timer.h~last_tick_fix 2005-06-22 10:02:05.000000000 +0800
+++ linux-2.6.12-mm1-root/include/asm-i386/timer.h 2005-06-22 10:02:05.000000000 +0800
@@ -1,6 +1,7 @@
#ifndef _ASMi386_TIMER_H
#define _ASMi386_TIMER_H
#include <linux/init.h>
+#include <linux/pm.h>
/**
* struct timer_ops - used to define a timer source
@@ -23,6 +24,8 @@ struct timer_opts {
unsigned long long (*monotonic_clock)(void);
void (*delay)(unsigned long);
unsigned long (*read_timer)(void);
+ int (*suspend)(pm_message_t state);
+ int (*resume)(void);
};
struct init_timer_opts {
diff -puN arch/i386/kernel/timers/timer_hpet.c~last_tick_fix arch/i386/kernel/timers/timer_hpet.c
--- linux-2.6.12-mm1/arch/i386/kernel/timers/timer_hpet.c~last_tick_fix 2005-06-22 10:02:05.000000000 +0800
+++ linux-2.6.12-mm1-root/arch/i386/kernel/timers/timer_hpet.c 2005-06-23 10:29:51.294011992 +0800
@@ -177,6 +177,19 @@ static int __init init_hpet(char* overri
return 0;
}
+static int hpet_resume(void)
+{
+ write_seqlock(&monotonic_lock);
+ /* Assume this is the last mark offset time */
+ rdtsc(last_tsc_low, last_tsc_high);
+
+ if (hpet_use_timer)
+ hpet_last = hpet_readl(HPET_T0_CMP) - hpet_tick;
+ else
+ hpet_last = hpet_readl(HPET_COUNTER);
+ write_sequnlock(&monotonic_lock);
+ return 0;
+}
/************************************************************/
/* tsc timer_opts struct */
@@ -187,6 +200,7 @@ static struct timer_opts timer_hpet __ca
.monotonic_clock = monotonic_clock_hpet,
.delay = delay_hpet,
.read_timer = read_timer_tsc,
+ .resume = hpet_resume,
};
struct init_timer_opts __initdata timer_hpet_init = {
diff -puN arch/i386/kernel/timers/timer_pit.c~last_tick_fix arch/i386/kernel/timers/timer_pit.c
--- linux-2.6.12-mm1/arch/i386/kernel/timers/timer_pit.c~last_tick_fix 2005-06-22 10:02:05.000000000 +0800
+++ linux-2.6.12-mm1-root/arch/i386/kernel/timers/timer_pit.c 2005-06-22 10:02:05.000000000 +0800
@@ -177,30 +177,3 @@ void setup_pit_timer(void)
outb(LATCH >> 8 , PIT_CH0); /* MSB */
spin_unlock_irqrestore(&i8253_lock, flags);
}
-
-static int timer_resume(struct sys_device *dev)
-{
- setup_pit_timer();
- return 0;
-}
-
-static struct sysdev_class timer_sysclass = {
- set_kset_name("timer_pit"),
- .resume = timer_resume,
-};
-
-static struct sys_device device_timer = {
- .id = 0,
- .cls = &timer_sysclass,
-};
-
-static int __init init_timer_sysfs(void)
-{
- int error = sysdev_class_register(&timer_sysclass);
- if (!error)
- error = sysdev_register(&device_timer);
- return error;
-}
-
-device_initcall(init_timer_sysfs);
-
diff -puN arch/i386/kernel/timers/timer_tsc.c~last_tick_fix arch/i386/kernel/timers/timer_tsc.c
--- linux-2.6.12-mm1/arch/i386/kernel/timers/timer_tsc.c~last_tick_fix 2005-06-22 10:02:05.000000000 +0800
+++ linux-2.6.12-mm1-root/arch/i386/kernel/timers/timer_tsc.c 2005-06-23 10:31:13.379533096 +0800
@@ -544,6 +544,19 @@ static int __init init_tsc(char* overrid
return -ENODEV;
}
+static int tsc_resume(void)
+{
+ write_seqlock(&monotonic_lock);
+ /* Assume this is the last mark offset time */
+ rdtsc(last_tsc_low, last_tsc_high);
+#ifdef CONFIG_HPET_TIMER
+ if (is_hpet_enabled() && hpet_use_timer)
+ hpet_last = hpet_readl(HPET_COUNTER);
+#endif
+ write_sequnlock(&monotonic_lock);
+ return 0;
+}
+
#ifndef CONFIG_X86_TSC
/* disable flag for tsc. Takes effect by clearing the TSC cpu flag
* in cpu/common.c */
@@ -574,6 +587,7 @@ static struct timer_opts timer_tsc = {
.monotonic_clock = monotonic_clock_tsc,
.delay = delay_tsc,
.read_timer = read_timer_tsc,
+ .resume = tsc_resume,
};
struct init_timer_opts __initdata timer_tsc_init = {
diff -puN arch/i386/kernel/timers/timer_pm.c~last_tick_fix arch/i386/kernel/timers/timer_pm.c
--- linux-2.6.12-mm1/arch/i386/kernel/timers/timer_pm.c~last_tick_fix 2005-06-22 10:02:05.000000000 +0800
+++ linux-2.6.12-mm1-root/arch/i386/kernel/timers/timer_pm.c 2005-06-23 10:31:54.412295168 +0800
@@ -186,6 +186,14 @@ static void mark_offset_pmtmr(void)
}
}
+static int pmtmr_resume(void)
+{
+ write_seqlock(&monotonic_lock);
+ /* Assume this is the last mark offset time */
+ offset_tick = read_pmtmr();
+ write_sequnlock(&monotonic_lock);
+ return 0;
+}
static unsigned long long monotonic_clock_pmtmr(void)
{
@@ -247,6 +255,7 @@ static struct timer_opts timer_pmtmr = {
.monotonic_clock = monotonic_clock_pmtmr,
.delay = delay_pmtmr,
.read_timer = read_timer_tsc,
+ .resume = pmtmr_resume,
};
struct init_timer_opts __initdata timer_pmtmr_init = {
diff -puN arch/i386/kernel/time.c~last_tick_fix arch/i386/kernel/time.c
--- linux-2.6.12-mm1/arch/i386/kernel/time.c~last_tick_fix 2005-06-22 10:02:05.000000000 +0800
+++ linux-2.6.12-mm1-root/arch/i386/kernel/time.c 2005-06-22 10:09:58.000000000 +0800
@@ -380,6 +380,7 @@ void notify_arch_cmos_timer(void)
static long clock_cmos_diff, sleep_start;
+static struct timer_opts *last_timer;
static int timer_suspend(struct sys_device *dev, pm_message_t state)
{
/*
@@ -388,6 +389,10 @@ static int timer_suspend(struct sys_devi
clock_cmos_diff = -get_cmos_time();
clock_cmos_diff += get_seconds();
sleep_start = get_cmos_time();
+ last_timer = cur_timer;
+ cur_timer = &timer_none;
+ if (last_timer->suspend)
+ last_timer->suspend(state);
return 0;
}
@@ -401,6 +406,7 @@ static int timer_resume(struct sys_devic
if (is_hpet_enabled())
hpet_reenable();
#endif
+ setup_pit_timer();
sec = get_cmos_time() + clock_cmos_diff;
sleep_length = (get_cmos_time() - sleep_start) * HZ;
write_seqlock_irqsave(&xtime_lock, flags);
@@ -410,6 +416,10 @@ static int timer_resume(struct sys_devic
jiffies += sleep_length;
wall_jiffies += sleep_length;
touch_softlockup_watchdog();
+ if (last_timer->resume)
+ last_timer->resume();
+ cur_timer = last_timer;
+ last_timer = NULL;
return 0;
}
_
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/