Page MenuHomeFreeBSD
Files F142448237

D24513.id.diff
No OneTemporary
Actions

D24513.id.diff
View Options

Index: head/sys/kern/kern_synch.c
===================================================================
--- head/sys/kern/kern_synch.c
+++ head/sys/kern/kern_synch.c
@@ -400,12 +400,12 @@
}
/*
- * Wait for a wakeup. This does not guarantee that the count is still zero on
- * return and may be subject to transient wakeups. Callers wanting a precise
- * answer should use blockcount_wait() with an interlock.
+ * Wait for a wakeup or a signal. This does not guarantee that the count is
+ * still zero on return. Callers wanting a precise answer should use
+ * blockcount_wait() with an interlock.
*
- * Return 0 if there is no work to wait for, and 1 if we slept waiting for work
- * to complete. In the latter case the counter value must be re-read.
+ * If there is no work to wait for, return 0. If the sleep was interrupted by a
+ * signal, return EINTR or ERESTART, and return EAGAIN otherwise.
*/
int
_blockcount_sleep(blockcount_t *bc, struct lock_object *lock, const char *wmesg,
@@ -415,10 +415,15 @@
uintptr_t lock_state;
u_int old;
int ret;
+ bool catch, drop;
KASSERT(lock != &Giant.lock_object,
("%s: cannot use Giant as the interlock", __func__));
+ catch = (prio & PCATCH) != 0;
+ drop = (prio & PDROP) != 0;
+ prio &= PRIMASK;
+
/*
* Synchronize with the fence in blockcount_release(). If we end up
* waiting, the sleepqueue lock acquisition will provide the required
@@ -428,7 +433,7 @@
* ourselves to sleep to avoid jumping ahead.
*/
if (atomic_load_acq_int(&bc->__count) == 0) {
- if (lock != NULL && (prio & PDROP) != 0)
+ if (lock != NULL && drop)
LOCK_CLASS(lock)->lc_unlock(lock);
return (0);
}
@@ -439,23 +444,27 @@
if (lock != NULL)
lock_state = LOCK_CLASS(lock)->lc_unlock(lock);
old = blockcount_read(bc);
+ ret = 0;
do {
if (_BLOCKCOUNT_COUNT(old) == 0) {
sleepq_release(wchan);
- ret = 0;
goto out;
}
if (_BLOCKCOUNT_WAITERS(old))
break;
} while (!atomic_fcmpset_int(&bc->__count, &old,
old | _BLOCKCOUNT_WAITERS_FLAG));
- sleepq_add(wchan, NULL, wmesg, 0, 0);
- sleepq_wait(wchan, prio);
- ret = 1;
+ sleepq_add(wchan, NULL, wmesg, catch ? SLEEPQ_INTERRUPTIBLE : 0, 0);
+ if (catch)
+ ret = sleepq_wait_sig(wchan, prio);
+ else
+ sleepq_wait(wchan, prio);
+ if (ret == 0)
+ ret = EAGAIN;
out:
PICKUP_GIANT();
- if (lock != NULL && (prio & PDROP) == 0)
+ if (lock != NULL && !drop)
LOCK_CLASS(lock)->lc_lock(lock, lock_state);
return (ret);
Index: head/sys/sys/blockcount.h
===================================================================
--- head/sys/sys/blockcount.h
+++ head/sys/sys/blockcount.h
@@ -80,9 +80,9 @@
_blockcount_wait(blockcount_t *bc, struct lock_object *lo, const char *wmesg,
int prio)
{
- KASSERT((prio & PDROP) == 0, ("%s: invalid prio %x", __func__, prio));
+ KASSERT((prio & ~PRIMASK) == 0, ("%s: invalid prio %x", __func__, prio));
- while (_blockcount_sleep(bc, lo, wmesg, prio) != 0)
+ while (_blockcount_sleep(bc, lo, wmesg, prio) == EAGAIN)
;
}

File Metadata

Mime Type
text/plain
Expires
Wed, Jan 21, 1:44 AM (20 h, 3 m)
Storage Engine
blob
Storage Format
Raw Data
Storage Handle
27786062
Default Alt Text
D24513.id.diff (2 KB)

Event Timeline