Changeset c0d814a in mainline for kernel/generic/src/synch/condvar.c

Timestamp:

2025-04-10T20:02:30Z (4 days ago)

Author:

GitHub <noreply@…>

Children:

b8b031f

Parents:

a92290d (diff), 90dd8aee (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

git-author:

Wayne Thornton <wmthornton-dev@…> (2025-04-10 20:02:30)

git-committer:

GitHub <noreply@…> (2025-04-10 20:02:30)

Message:

Merge pull request #6 from HelenOS/master

Merge pending changes from downstream helenos/master

File:

• kernel/generic/src/synch/condvar.c (modified) (6 diffs)

kernel/generic/src/synch/condvar.c

@@ -79 +79 @@
  * @return              See comment for waitq_sleep_timeout().
  */
-errno_t condvar_wait_timeout(condvar_t *cv, mutex_t *mtx, uint32_t usec)
+errno_t __condvar_wait_timeout_mutex(condvar_t *cv, mutex_t *mtx, uint32_t usec)
 {
         wait_guard_t guard = waitq_sleep_prepare(&cv->wq);
@@ -92 +92 @@
 }
 
-errno_t condvar_wait(condvar_t *cv, mutex_t *mtx)
+errno_t __condvar_wait_mutex(condvar_t *cv, mutex_t *mtx)
 {
         wait_guard_t guard = waitq_sleep_prepare(&cv->wq);
@@ -105 +105 @@
 }
 
-/** Wait for the condition to become true with a locked spinlock.
- *
- * The function is not aware of irq_spinlock. Therefore do not even
- * try passing irq_spinlock_t to it. Use _condvar_wait_timeout_irq_spinlock()
- * instead.
- *
- * @param cv            Condition variable.
- * @param lock          Locked spinlock.
- * @param usec          Timeout value in microseconds.
- * @param flags         Select mode of operation.
- *
- * For exact description of meaning of possible combinations of usec and flags,
- * see comment for waitq_sleep_timeout().  Note that when
- * SYNCH_FLAGS_NON_BLOCKING is specified here, EAGAIN is always
- * returned.
- *
- * @return See comment for waitq_sleep_timeout().
- */
-errno_t _condvar_wait_timeout_spinlock_impl(condvar_t *cv, spinlock_t *lock,
-    uint32_t usec, int flags)
+/** Same as __condvar_wait_timeout_mutex(), except for spinlock_t. */
+errno_t __condvar_wait_timeout_spinlock(condvar_t *cv, spinlock_t *lock,
+    uint32_t usec)
 {
         wait_guard_t guard = waitq_sleep_prepare(&cv->wq);
@@ -131 +114 @@
         spinlock_unlock(lock);
 
-        errno_t rc = waitq_sleep_timeout_unsafe(&cv->wq, usec, flags, guard);
+        errno_t rc = waitq_sleep_timeout_unsafe(&cv->wq, usec,
+            SYNCH_FLAGS_NON_BLOCKING, guard);
 
         spinlock_lock(lock);
@@ -137 +121 @@
 }
 
-/** Wait for the condition to become true with a locked irq spinlock.
- *
- * @param cv            Condition variable.
- * @param lock          Locked irq spinlock.
- * @param usec          Timeout value in microseconds.
- * @param flags         Select mode of operation.
- *
- * For exact description of meaning of possible combinations of usec and flags,
- * see comment for waitq_sleep_timeout().  Note that when
- * SYNCH_FLAGS_NON_BLOCKING is specified here, EAGAIN is always
- * returned.
- *
- * @return See comment for waitq_sleep_timeout().
- */
-errno_t _condvar_wait_timeout_irq_spinlock(condvar_t *cv, irq_spinlock_t *irq_lock,
-    uint32_t usec, int flags)
+errno_t __condvar_wait_spinlock(condvar_t *cv, spinlock_t *mtx)
+{
+        wait_guard_t guard = waitq_sleep_prepare(&cv->wq);
+
+        /* Unlock only after the waitq is locked so we don't miss a wakeup. */
+        spinlock_unlock(mtx);
+
+        errno_t rc = waitq_sleep_unsafe(&cv->wq, guard);
+
+        spinlock_lock(mtx);
+        return rc;
+}
+
+/** Same as __condvar_wait_timeout_mutex(), except for irq_spinlock_t. */
+errno_t __condvar_wait_timeout_irq_spinlock(condvar_t *cv,
+    irq_spinlock_t *irq_lock, uint32_t usec)
 {
         errno_t rc;
@@ -171 +155 @@
          * running) and there is no danger of a deadlock.
          */
-        rc = _condvar_wait_timeout_spinlock(cv, &irq_lock->lock, usec, flags);
+        rc = __condvar_wait_timeout_spinlock(cv, &irq_lock->lock, usec);
+
+        irq_lock->guard = guard;
+        irq_lock->ipl = ipl;
+
+        return rc;
+}
+
+/** Same as __condvar_wait_mutex(), except for irq_spinlock_t. */
+errno_t __condvar_wait_irq_spinlock(condvar_t *cv, irq_spinlock_t *irq_lock)
+{
+        errno_t rc;
+        /* Save spinlock's state so we can restore it correctly later on. */
+        ipl_t ipl = irq_lock->ipl;
+        bool guard = irq_lock->guard;
+
+        irq_lock->guard = false;
+
+        rc = __condvar_wait_spinlock(cv, &irq_lock->lock);
 
         irq_lock->guard = guard;