2002-10-02 09:30:09

by Hanumanthu. H

[permalink] [raw]
Subject: [PATCH, 2.5.40] Add wait_event_timeout & change wait_event_interruptible_timeout ret val

Hi,

Nice to have wait_event_interruptible_timeout, but it would be
necessary to return -ETIME upon timeout expiration (we need this
behaviour please !!). The following patch makes trivial changes
to __wait_even_interruptible_timeout macro to behave as below:

if timeout occurs return -ETIME
if interrupted, return -ERESTARTSYS
if condition becomes true within specified timeout
then return the remaining timeout

It also adds wait_event_timeout macro (again, we require it)

Please apply

~Hanu


--- linux-2.5.40/include/linux/sched.h Wed Oct 2 13:59:47 2002
+++ linux/include/linux/sched.h Wed Oct 2 14:37:52 2002
@@ -697,6 +697,33 @@
__wait_event(wq, condition); \
} while (0)

+#define __wait_event_timeout(wq, condition, ret) \
+do { \
+ wait_queue_t __wait; \
+ init_waitqueue_entry(&__wait, current); \
+ \
+ add_wait_queue(&wq, &__wait); \
+ for (;;) { \
+ set_current_state(TASK_UNINTERRUPTIBLE); \
+ if (condition) \
+ break; \
+ if(ret = schedule_timeout(ret)) \
+ continue; \
+ ret = -ETIME; \
+ break; \
+ } \
+ current->state = TASK_RUNNING; \
+ remove_wait_queue(&wq, &__wait); \
+} while (0)
+
+#define wait_event_timeout(wq, condition, timeout) \
+({ \
+ long __ret = timeout; \
+ if (!(condition)) \
+ __wait_event_timeout(wq, condition, __ret); \
+ __ret; \
+})
+
#define __wait_event_interruptible(wq, condition, ret) \
do { \
wait_queue_t __wait; \
@@ -726,7 +753,7 @@
__ret; \
})

-#define __wait_event_interruptible_timeout(wq, condition, ret) \
+#define __wait_event_interruptible_timeout(wq, condition, tout, ret) \
do { \
wait_queue_t __wait; \
init_waitqueue_entry(&__wait, current); \
@@ -737,10 +764,10 @@
if (condition) \
break; \
if (!signal_pending(current)) { \
- ret = schedule_timeout(ret); \
- if (!ret) \
- break; \
- continue; \
+ if(tout = schedule_timeout(tout)) \
+ continue; \
+ ret = -ETIME; \
+ break; \
} \
ret = -ERESTARTSYS; \
break; \
@@ -751,10 +778,10 @@

#define wait_event_interruptible_timeout(wq, condition, timeout) \
({ \
- long __ret = timeout; \
+ long __tout = timeout, __ret = 0; \
if (!(condition)) \
- __wait_event_interruptible_timeout(wq, condition, __ret); \
- __ret; \
+ __wait_event_interruptible_timeout(wq, condition, __tout, __ret); \
+ (__ret == 0) ? __tout : __ret; \
})

/*