From: Tiwei Bie <tiwei....@antgroup.com>
Define timers on a per-CPU basis to enable each CPU to have its
own timer. This is a preparation for adding SMP support.
Signed-off-by: Tiwei Bie <tiwei....@antgroup.com>
---
arch/um/include/linux/time-internal.h | 3 ++
arch/um/include/shared/os.h | 6 +--
arch/um/kernel/irq.c | 2 +-
arch/um/kernel/time.c | 54 +++++++++++++++++++--------
arch/um/os-Linux/main.c | 2 +-
arch/um/os-Linux/time.c | 28 +++++++++-----
6 files changed, 66 insertions(+), 29 deletions(-)
diff --git a/arch/um/include/linux/time-internal.h
b/arch/um/include/linux/time-internal.h
index 138908b999d7..c274eb5ad55e 100644
--- a/arch/um/include/linux/time-internal.h
+++ b/arch/um/include/linux/time-internal.h
@@ -90,4 +90,7 @@ extern unsigned long tt_extra_sched_jiffies;
* which is intentional since we really shouldn't link it in that case.
*/
void time_travel_ndelay(unsigned long nsec);
+
+int um_setup_timer(void);
+
#endif /* __TIMER_INTERNAL_H__ */
diff --git a/arch/um/include/shared/os.h b/arch/um/include/shared/os.h
index 324d4eed3385..0ca6e4548671 100644
--- a/arch/um/include/shared/os.h
+++ b/arch/um/include/shared/os.h
@@ -269,9 +269,9 @@ extern void os_warn(const char *fmt, ...)
/* time.c */
extern void os_idle_sleep(void);
extern int os_timer_create(void);
-extern int os_timer_set_interval(unsigned long long nsecs);
-extern int os_timer_one_shot(unsigned long long nsecs);
-extern void os_timer_disable(void);
+extern int os_timer_set_interval(int cpu, unsigned long long nsecs);
+extern int os_timer_one_shot(int cpu, unsigned long long nsecs);
+extern void os_timer_disable(int cpu);
extern long long os_persistent_clock_emulation(void);
extern long long os_nsecs(void);
diff --git a/arch/um/kernel/irq.c b/arch/um/kernel/irq.c
index 0dfaf96bb7da..5ed8014e43e4 100644
--- a/arch/um/kernel/irq.c
+++ b/arch/um/kernel/irq.c
@@ -683,7 +683,7 @@ void __init init_IRQ(void)
{
int i;
- irq_set_chip_and_handler(TIMER_IRQ, &alarm_irq_type, handle_edge_irq);
+ irq_set_chip_and_handler(TIMER_IRQ, &alarm_irq_type, handle_percpu_irq);
for (i = 1; i < UM_LAST_SIGNAL_IRQ; i++)
irq_set_chip_and_handler(i, &normal_irq_type, handle_edge_irq);
diff --git a/arch/um/kernel/time.c b/arch/um/kernel/time.c
index ae0fa2173778..79c40fe5c80a 100644
--- a/arch/um/kernel/time.c
+++ b/arch/um/kernel/time.c
@@ -625,9 +625,10 @@ void time_travel_sleep(void)
* controller application.
*/
unsigned long long next = S64_MAX;
+ int cpu = raw_smp_processor_id();
if (time_travel_mode == TT_MODE_BASIC)
- os_timer_disable();
+ os_timer_disable(cpu);
time_travel_update_time(next, true);
@@ -638,9 +639,9 @@ void time_travel_sleep(void)
* This is somewhat wrong - we should get the first
* one sooner like the os_timer_one_shot() below...
*/
- os_timer_set_interval(time_travel_timer_interval);
+ os_timer_set_interval(cpu, time_travel_timer_interval);
} else {
- os_timer_one_shot(time_travel_timer_event.time - next);
+ os_timer_one_shot(cpu, time_travel_timer_event.time -
next);
}
}
}
@@ -758,6 +759,8 @@ extern u64 time_travel_ext_req(u32 op, u64 time);
#define time_travel_del_event(e) do { } while (0)
#endif
+static struct clock_event_device timer_clockevent[NR_CPUS];
+
void timer_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs
*regs)
{
unsigned long flags;
@@ -780,12 +783,14 @@ void timer_handler(int sig, struct siginfo *unused_si,
struct uml_pt_regs *regs)
static int itimer_shutdown(struct clock_event_device *evt)
{
+ int cpu = evt - &timer_clockevent[0];
+
if (time_travel_mode != TT_MODE_OFF)
time_travel_del_event(&time_travel_timer_event);
if (time_travel_mode != TT_MODE_INFCPU &&
time_travel_mode != TT_MODE_EXTERNAL)
- os_timer_disable();
+ os_timer_disable(cpu);
return 0;
}
@@ -793,6 +798,7 @@ static int itimer_shutdown(struct clock_event_device *evt)
static int itimer_set_periodic(struct clock_event_device *evt)
{
unsigned long long interval = NSEC_PER_SEC / HZ;
+ int cpu = evt - &timer_clockevent[0];
if (time_travel_mode != TT_MODE_OFF) {
time_travel_del_event(&time_travel_timer_event);
@@ -805,7 +811,7 @@ static int itimer_set_periodic(struct clock_event_device
*evt)
if (time_travel_mode != TT_MODE_INFCPU &&
time_travel_mode != TT_MODE_EXTERNAL)
- os_timer_set_interval(interval);
+ os_timer_set_interval(cpu, interval);
return 0;
}
@@ -825,7 +831,7 @@ static int itimer_next_event(unsigned long delta,
if (time_travel_mode != TT_MODE_INFCPU &&
time_travel_mode != TT_MODE_EXTERNAL)
- return os_timer_one_shot(delta);
+ return os_timer_one_shot(raw_smp_processor_id(), delta);
return 0;
}
@@ -835,10 +841,9 @@ static int itimer_one_shot(struct clock_event_device *evt)
return itimer_next_event(0, evt);
}
-static struct clock_event_device timer_clockevent = {
+static struct clock_event_device _timer_clockevent = {
.name = "posix-timer",
.rating = 250,
- .cpumask = cpu_possible_mask,
.features = CLOCK_EVT_FEAT_PERIODIC |
CLOCK_EVT_FEAT_ONESHOT,
.set_state_shutdown = itimer_shutdown,
@@ -856,6 +861,9 @@ static struct clock_event_device timer_clockevent = {
static irqreturn_t um_timer(int irq, void *dev)
{
+ int cpu = raw_smp_processor_id();
+ struct clock_event_device *evt = &timer_clockevent[cpu];
+
/*
* Interrupt the (possibly) running userspace process, technically this
* should only happen if userspace is currently executing.
@@ -867,7 +875,7 @@ static irqreturn_t um_timer(int irq, void *dev)
get_current()->mm)
os_alarm_process(get_current()->mm->context.id.pid);
- (*timer_clockevent.event_handler)(&timer_clockevent);
+ evt->event_handler(evt);
return IRQ_HANDLED;
}
@@ -904,6 +912,23 @@ static struct clocksource timer_clocksource = {
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
+int um_setup_timer(void)
+{
+ int cpu = raw_smp_processor_id();
+ struct clock_event_device *evt = &timer_clockevent[cpu];
+ int err;
+
+ err = os_timer_create();
+ if (err)
+ return err;
+
+ memcpy(evt, &_timer_clockevent, sizeof(*evt));
+ evt->cpumask = cpumask_of(cpu);
+ clockevents_register_device(evt);
+
+ return 0;
+}
+
static void __init um_timer_setup(void)
{
int err;
@@ -913,8 +938,8 @@ static void __init um_timer_setup(void)
printk(KERN_ERR "register_timer : request_irq failed - "
"errno = %d\n", -err);
- err = os_timer_create();
- if (err != 0) {
+ err = um_setup_timer();
+ if (err) {
printk(KERN_ERR "creation of timer failed - errno = %d\n",
-err);
return;
}
@@ -924,7 +949,6 @@ static void __init um_timer_setup(void)
printk(KERN_ERR "clocksource_register_hz returned %d\n", err);
return;
}
- clockevents_register_device(&timer_clockevent);
}
void read_persistent_clock64(struct timespec64 *ts)
@@ -961,21 +985,21 @@ static int setup_time_travel(char *str)
{
if (strcmp(str, "=inf-cpu") == 0) {
time_travel_mode = TT_MODE_INFCPU;
- timer_clockevent.name = "time-travel-timer-infcpu";
+ _timer_clockevent.name = "time-travel-timer-infcpu";
timer_clocksource.name = "time-travel-clock";
return 1;
}
if (strncmp(str, "=ext:", 5) == 0) {
time_travel_mode = TT_MODE_EXTERNAL;
- timer_clockevent.name = "time-travel-timer-external";
+ _timer_clockevent.name = "time-travel-timer-external";
timer_clocksource.name = "time-travel-clock-external";
return time_travel_connect_external(str + 5);
}
if (!*str) {
time_travel_mode = TT_MODE_BASIC;
- timer_clockevent.name = "time-travel-timer";
+ _timer_clockevent.name = "time-travel-timer";
timer_clocksource.name = "time-travel-clock";
return 1;
}
diff --git a/arch/um/os-Linux/main.c b/arch/um/os-Linux/main.c
index 3c63ce19e3bf..730723106228 100644
--- a/arch/um/os-Linux/main.c
+++ b/arch/um/os-Linux/main.c
@@ -171,7 +171,7 @@ int __init main(int argc, char **argv, char **envp)
*/
/* stop timers and set timer signal to be ignored */
- os_timer_disable();
+ os_timer_disable(0);
/* disable SIGIO for the fds and set SIGIO to be ignored */
err = deactivate_all_fds();
diff --git a/arch/um/os-Linux/time.c b/arch/um/os-Linux/time.c
index f25a4196bab7..e38b6f84287b 100644
--- a/arch/um/os-Linux/time.c
+++ b/arch/um/os-Linux/time.c
@@ -16,7 +16,7 @@
#include <os.h>
#include <string.h>
-static timer_t event_high_res_timer = 0;
+static timer_t event_high_res_timer[CONFIG_NR_CPUS] = { 0 };
static inline long long timespec_to_ns(const struct timespec *ts)
{
@@ -31,20 +31,30 @@ long long os_persistent_clock_emulation(void)
return timespec_to_ns(&realtime_tp);
}
+#ifndef sigev_notify_thread_id
+#define sigev_notify_thread_id _sigev_un._tid
+#endif
+
/**
* os_timer_create() - create an new posix (interval) timer
*/
int os_timer_create(void)
{
- timer_t *t = &event_high_res_timer;
+ timer_t *t = &event_high_res_timer[0];
+ struct sigevent sev = {
+ .sigev_notify = SIGEV_THREAD_ID,
+ .sigev_signo = SIGALRM,
+ .sigev_value.sival_ptr = t,
+ .sigev_notify_thread_id = gettid(),
+ };
- if (timer_create(CLOCK_MONOTONIC, NULL, t) == -1)
+ if (timer_create(CLOCK_MONOTONIC, &sev, t) == -1)
return -1;
return 0;
}
-int os_timer_set_interval(unsigned long long nsecs)
+int os_timer_set_interval(int cpu, unsigned long long nsecs)
{
struct itimerspec its;
@@ -54,13 +64,13 @@ int os_timer_set_interval(unsigned long long nsecs)
its.it_interval.tv_sec = nsecs / UM_NSEC_PER_SEC;
its.it_interval.tv_nsec = nsecs % UM_NSEC_PER_SEC;
- if (timer_settime(event_high_res_timer, 0, &its, NULL) == -1)
+ if (timer_settime(event_high_res_timer[cpu], 0, &its, NULL) == -1)
return -errno;
return 0;
}
-int os_timer_one_shot(unsigned long long nsecs)
+int os_timer_one_shot(int cpu, unsigned long long nsecs)
{
struct itimerspec its = {
.it_value.tv_sec = nsecs / UM_NSEC_PER_SEC,
@@ -70,19 +80,19 @@ int os_timer_one_shot(unsigned long long nsecs)
.it_interval.tv_nsec = 0, // we cheat here
};
- timer_settime(event_high_res_timer, 0, &its, NULL);
+ timer_settime(event_high_res_timer[cpu], 0, &its, NULL);
return 0;
}
/**
* os_timer_disable() - disable the posix (interval) timer
*/
-void os_timer_disable(void)
+void os_timer_disable(int cpu)
{
struct itimerspec its;
memset(&its, 0, sizeof(struct itimerspec));
- timer_settime(event_high_res_timer, 0, &its, NULL);
+ timer_settime(event_high_res_timer[cpu], 0, &its, NULL);
}
long long os_nsecs(void)
--
2.34.1
