diff options
Diffstat (limited to 'rts/Schedule.c')
| -rw-r--r-- | rts/Schedule.c | 32 |
1 files changed, 20 insertions, 12 deletions
diff --git a/rts/Schedule.c b/rts/Schedule.c index 2b25c96b71..7f9433c0ec 100644 --- a/rts/Schedule.c +++ b/rts/Schedule.c @@ -30,7 +30,6 @@ #include "Sparks.h" #include "Capability.h" #include "Task.h" -#include "AwaitEvent.h" #include "IOManager.h" #if defined(mingw32_HOST_OS) #include "win32/MIOManager.h" @@ -317,6 +316,9 @@ schedule (Capability *initialCapability, Task *task) /* Notify the I/O manager that we have nothing to do. If there are any outstanding I/O requests we'll block here. If there are not then this is a user error and we will abort soon. */ + /* TODO: see if we can rationalise these two awaitEvent calls before + * and after scheduleDetectDeadlock(). + */ awaitEvent (emptyRunQueue(cap)); #else ASSERT(sched_state >= SCHED_INTERRUPTING); @@ -900,17 +902,23 @@ static void scheduleCheckBlockedThreads(Capability *cap USED_IF_NOT_THREADS) { #if !defined(THREADED_RTS) - // - // Check whether any waiting threads need to be woken up. If the - // run queue is empty, and there are no other tasks running, we - // can wait indefinitely for something to happen. - // - // TODO: this empty-queue test is highly dubious because it only makes - // sense for some I/O managers. The sleeping_queue is _only_ used by the - // select() I/O manager. The WinIO I/O manager does not use either the - // sleeping_queue or the blocked_queue, so both queues will _always_ be - // empty and so awaitEvent will _never_ be called here for WinIO. This may - // explain why there is a second call to awaitEvent below for mingw32. + /* Check whether there is any completed I/O or expired timers. If so, + * process the competions as appropriate, which will typically cause some + * waiting threads to be woken up. + * + * If the run queue is empty, and there are no other threads running, we + * can wait indefinitely for something to happen. + * + * TODO: see if we can rationalise these two awaitEvent calls before + * and after scheduleDetectDeadlock() + * + * TODO: these empty-queue tests are highly dubious because they only make + * sense for some I/O managers. The sleeping_queue is _only_ used by the + * select() I/O manager. The WinIO I/O manager does not use either the + * sleeping_queue or the blocked_queue, so both queues will _always_ be + * empty and so awaitEvent will _never_ be called here for WinIO. This may + * explain why there is a second call to awaitEvent below for mingw32. + */ if (anyPendingTimeoutsOrIO(cap->iomgr)) { awaitEvent (emptyRunQueue(cap)); |