diff options
| -rw-r--r-- | os/nil/src/ch.c | 21 |
1 files changed, 14 insertions, 7 deletions
diff --git a/os/nil/src/ch.c b/os/nil/src/ch.c index 562259913..7fdf6812f 100644 --- a/os/nil/src/ch.c +++ b/os/nil/src/ch.c @@ -326,7 +326,7 @@ void chSysTimerHandlerI(void) { chDbgAssert(!NIL_THD_IS_READY(tp), "is ready");
- /* Did the timer reach zero?*/
+ /* Did the timer reach zero?*/
if (--tp->timeout == (systime_t)0) {
/* Timeout on semaphores requires a special handling because the
semaphore counter must be incremented.*/
@@ -354,14 +354,19 @@ void chSysTimerHandlerI(void) { chDbgAssert(nil.nexttime == port_timer_get_alarm(), "time mismatch");
do {
+ systime_t timeout = tp->timeout;
+
/* Is the thread in a wait state with timeout?.*/
- if (tp->timeout > (systime_t)0) {
+ if (timeout > (systime_t)0) {
chDbgAssert(!NIL_THD_IS_READY(tp), "is ready");
- chDbgAssert(tp->timeout >= (nil.nexttime - nil.lasttime), "skipped one");
+ chDbgAssert(timeout >= (nil.nexttime - nil.lasttime), "skipped one");
+
+ /* The volatile field is updated once, here.*/
+ timeout -= nil.nexttime - nil.lasttime;
+ tp->timeout = timeout;
- tp->timeout -= nil.nexttime - nil.lasttime;
- if (tp->timeout == (systime_t)0) {
+ if (timeout == (systime_t)0) {
#if CH_CFG_USE_SEMAPHORES == TRUE
/* Timeout on semaphores requires a special handling because the
semaphore counter must be incremented.*/
@@ -379,17 +384,19 @@ void chSysTimerHandlerI(void) { (void) chSchReadyI(tp, MSG_TIMEOUT);
}
else {
- if (tp->timeout <= (systime_t)(next - (systime_t)1)) {
- next = tp->timeout;
+ if (timeout <= (systime_t)(next - (systime_t)1)) {
+ next = timeout;
}
}
}
+
/* Lock released in order to give a preemption chance on those
architectures supporting IRQ preemption.*/
chSysUnlockFromISR();
tp++;
chSysLockFromISR();
} while (tp < &nil.threads[CH_CFG_NUM_THREADS]);
+
nil.lasttime = nil.nexttime;
if (next > (systime_t)0) {
nil.nexttime += next;
|