diff options
| -rw-r--r-- | include/sys/schedule.h | 1 | ||||
| -rw-r--r-- | src/sys/schedule.c | 78 | ||||
| -rw-r--r-- | src/tests/test.c | 4 |
3 files changed, 58 insertions, 25 deletions
diff --git a/include/sys/schedule.h b/include/sys/schedule.h index 798786d..a76b52b 100644 --- a/include/sys/schedule.h +++ b/include/sys/schedule.h @@ -33,6 +33,7 @@ struct Thread { unsigned char preempt; unsigned short status; void* mptr; + unsigned char old_priority; }; struct ThreadRotBuffer { diff --git a/src/sys/schedule.c b/src/sys/schedule.c index 913d66e..3374f7e 100644 --- a/src/sys/schedule.c +++ b/src/sys/schedule.c @@ -18,6 +18,7 @@ void init_scheduler(void) usrloopthread.mptr = 0; usrloopthread.pid = -1; usrloopthread.priority = -1; + usrloopthread.old_priority = -1; usrloopthread.status = THREAD_READY; scheduler.rthread = &usrloopthread; // Initialize Rotating Buffers @@ -94,6 +95,7 @@ void add_thread(void* pc, void* arg, unsigned char priority) thread->mptr = (void*)0; thread->pid = nextpid++; thread->priority = priority % PRIORITIES; + thread->old_priority = -1; thread->preempt = 0; // Add Thread* to scheduler's appropriate buffer struct ThreadQueues* tq = &scheduler.thread_queues[thread->priority]; @@ -185,34 +187,47 @@ void sched_mutex_yield(void* m) return; unsigned char priority = rthread->priority; rthread->mptr = m; - struct ThreadRotBuffer* trb = &scheduler.thread_queues[priority].ready; + struct ThreadRotBuffer* trbb = &scheduler.thread_queues[priority].ready; struct ThreadRotBuffer* trbm = &scheduler.thread_queues[priority].mwait; - trb->roffset += 1; - trb->roffset %= TQUEUE_MAX; + trbb->roffset += 1; + trbb->roffset %= TQUEUE_MAX; trbm->queue[trbm->woffset++] = rthread; trbm->woffset %= TQUEUE_MAX; - for (int p = 0; p < PRIORITIES; p++) { - struct ThreadRotBuffer* trbm = &scheduler.thread_queues[p].mwait; - unsigned long roffset = trbm->roffset; - while (roffset != trbm->woffset) { - if (trbm->queue[roffset]->mptr == m && trbm->queue[roffset] != rthread) { - trb->queue[trb->woffset++] = trbm->queue[roffset]; - trb->woffset %= TQUEUE_MAX; - // Copy all next backward to fill space - unsigned long coffset = roffset; - while (coffset != trbm->woffset) { - trbm->queue[coffset] = trbm->queue[(coffset+1)%TQUEUE_MAX]; - coffset++; - coffset %= TQUEUE_MAX; + // Find the thread with the mutex + struct ThreadQueues* tq; + for (int i = 0; i < PRIORITIES; i++) { + tq = &scheduler.thread_queues[i]; + struct ThreadRotBuffer* trb = &tq->ready; + for (int i = 0; i < TQUEUE_CNT; i++) { + unsigned long roffset = trb->roffset; + unsigned long woffset = trb->woffset; + while(roffset != woffset) { + // Found thread + if (trb->queue[roffset]->pid == ((struct Mutex*)m)->pid) { + // Promote the thread to the new priority + if (trb->queue[roffset]->priority > priority) { + trbb->queue[trbb->woffset++] = trb->queue[roffset]; + if(trb->queue[roffset]->old_priority == 0xFF) + trb->queue[roffset]->old_priority = trb->queue[roffset]->priority; + trb->queue[roffset]->priority = priority; + trbb->woffset %= TQUEUE_MAX; + unsigned long coffset = roffset; + while (coffset != woffset) { + trb->queue[coffset] = trb->queue[(coffset+1)%TQUEUE_MAX]; + coffset++; + coffset %= TQUEUE_MAX; + } + if (trb->woffset == 0) + trb->woffset = TQUEUE_MAX-1; + else + trb->woffset--; + } + return; } - if(trbm->woffset == 0) - trbm->woffset = TQUEUE_MAX-1; - else - trbm->woffset--; - return; + roffset++; + roffset %= TQUEUE_MAX; } - roffset++; - roffset %= TQUEUE_MAX; + trb += 1; } } } @@ -239,6 +254,21 @@ void sched_mutex_resurrect(void* m) trbm->woffset = TQUEUE_MAX-1; else trbm->woffset--; + // Move the read pointer ahead + struct Thread* rthread = scheduler.rthread; + if (rthread->old_priority != 0xFF) { + struct ThreadRotBuffer* rtrb = &scheduler.thread_queues[rthread->priority].ready; + struct ThreadRotBuffer* ntrb = &scheduler.thread_queues[rthread->old_priority].ready; + rtrb->roffset++; + rtrb->roffset %= TQUEUE_MAX; + if (ntrb->roffset == 0) + ntrb->roffset = TQUEUE_MAX-1; + else + ntrb->roffset--; + ntrb->queue[ntrb->roffset] = rthread; + rthread->priority = rthread->old_priority; + rthread->old_priority = -1; + } return; } roffset++; @@ -246,3 +276,5 @@ void sched_mutex_resurrect(void* m) } } } + +// TODO: Check offsets diff --git a/src/tests/test.c b/src/tests/test.c index d828163..bb1bf31 100644 --- a/src/tests/test.c +++ b/src/tests/test.c @@ -46,8 +46,7 @@ void ctest1(void) uart_string("1 Started\n"); uart_string("1 Locking\n"); lock(&testm); - add_thread(ctest3, 0, 3); - add_thread(ctest2, 0, 2); + add_thread(ctest3, 0, 2); uart_string("1 Unlocking\n"); unlock(&testm); uart_string("1 Finished\n"); @@ -67,6 +66,7 @@ void ctest2(void) void ctest3(void) { uart_string("3 Started\n"); + add_thread(ctest2, 0, 1); uart_string("3 Finished\n"); } |