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authorChristian Cunningham <cc@localhost>2022-08-26 22:31:52 -0700
committerChristian Cunningham <cc@localhost>2022-08-26 22:31:52 -0700
commit8b36a39774789cee66d84db9f0086af15cacc211 (patch)
treeaa0345e480b796623fc5a20de6e519a4fce0395b /kernel
parente36b9514b79c3f67c42c41fada2e46a5ecc3fa05 (diff)
No used mutex queue
Diffstat (limited to 'kernel')
-rw-r--r--kernel/sys/schedule.c2
-rw-r--r--kernel/util/mutex.c68
2 files changed, 20 insertions, 50 deletions
diff --git a/kernel/sys/schedule.c b/kernel/sys/schedule.c
index 3157c5d..142ffaf 100644
--- a/kernel/sys/schedule.c
+++ b/kernel/sys/schedule.c
@@ -21,6 +21,7 @@ void init_scheduler(void)
usrloopthread.old_priority = -1;
usrloopthread.status = THREAD_READY;
usrloopthread.offset = -1;
+ usrloopthread.highest_mutex = 0;
scheduler.rthread = &usrloopthread;
// Initialize Scheduling Queues
@@ -56,6 +57,7 @@ void init_scheduler(void)
struct Thread* t = &threads[i];
t->offset = i;
t->sp_base = 0x20000000 - STACK_SIZE*i;
+ t->highest_mutex = 0;
thread_entries[i].value = t;
thread_entries[i].next = &thread_entries[(i+1)];
thread_entries[i].entry_type = VALUE_ENTRY;
diff --git a/kernel/util/mutex.c b/kernel/util/mutex.c
index 8e85f8f..997d85d 100644
--- a/kernel/util/mutex.c
+++ b/kernel/util/mutex.c
@@ -21,13 +21,6 @@ void mutex_init(void)
mutex_manager.free.end.next = &mutex_entries[MAX_MUTEXS-1];
mutex_entries[MAX_MUTEXS-1].next = &mutex_manager.free.end;
mutex_manager.free.end.entry_type = END_ENTRY;
- // Initialize In-use Mutexs
- mutex_manager.used.start.value = 0;
- mutex_manager.used.start.next = &mutex_manager.used.end;
- mutex_manager.used.start.entry_type = START_ENTRY;
- mutex_manager.used.end.value = 0;
- mutex_manager.used.end.next = &mutex_manager.used.start;
- mutex_manager.used.end.entry_type = END_ENTRY;
}
struct Mutex* create_mutex(void* addr)
@@ -38,70 +31,45 @@ struct Mutex* create_mutex(void* addr)
struct Mutex* m = e->value;
m->pid = 0;
m->addr = addr;
- push_to_queue(e, &mutex_manager.used);
+ mutex_manager.used_mutexes++;
return e->value;
}
unsigned char delete_mutex(struct Mutex* m)
{
- struct Entry* entry = find_value(m, &mutex_manager.used);
- if (entry == 0)
+ unsigned long spacing = (unsigned long)&mutexs[1] - (unsigned long)&mutexs[0];
+ unsigned long difference = (unsigned long)m - (unsigned long)&mutexs[0];
+ unsigned long index = difference/spacing;
+ if (index >= MAX_MUTEXS)
return 1;
- // Remove it from the queue
- struct Entry* theentry = remove_next_from_queue(entry);
+ struct Entry* entry = &mutex_entries[index];
// Add it to the free queue
- prepend_to_queue(theentry, &mutex_manager.free);
+ prepend_to_queue(entry, &mutex_manager.free);
return 0;
}
void uart_mutexes(void)
{
- struct Entry* entry = mutex_manager.used.start.next;
- while (entry->entry_type == VALUE_ENTRY)
- {
- struct Mutex* m = entry->value;
- uart_hex((unsigned long)m);
- uart_char(' ');
- uart_hex(m->pid);
- uart_char(' ');
- uart_hexn((unsigned long)m->addr);
- entry = entry->next;
- }
- unsigned long count = 0;
- entry = mutex_manager.free.start.next;
- while (entry->entry_type == VALUE_ENTRY) {
- count++;
- entry = entry->next;
- }
- uart_hexn(count);
+ uart_hexn(mutex_manager.used_mutexes);
}
-void lock_mutex(struct Mutex* m)
+unsigned char lock_mutex(struct Mutex* m)
{
struct Thread* rthread = scheduler.rthread;
- unsigned long rpid = rthread->pid;
unsigned long mode = getmode() & 0x1F;
if (mode == 0x10) {
- // Find this mutex
- struct Entry* mentry = find_value(m, &mutex_manager.used);
+ unsigned long spacing = (unsigned long)&mutexs[1] - (unsigned long)&mutexs[0];
+ unsigned long difference = (unsigned long)m - (unsigned long)&mutexs[0];
+ unsigned long index = difference/spacing;
// If it is not a managed mutex, break away
- if (mentry == 0)
- return;
- struct Entry* entry = mutex_manager.used.start.next;
- // Ensure this thread locks all mutexs sequentially
- // To avoid a deadlock
- while (entry->entry_type == VALUE_ENTRY) {
- struct Mutex* vmutex = entry->value;
- // If this thread had locked it
- // Toggle the lock to prevent deadlock
- if (vmutex->pid == rpid) {
- sys1(SYS_UNLOCK, vmutex);
- sys1(SYS_LOCK, vmutex);
- }
- entry = entry->next;
- }
+ if (index >= MAX_MUTEXS)
+ return 1;
+ if ((unsigned char) index > rthread->highest_mutex)
+ return 2;
sys1(SYS_LOCK, m);
+ return 0;
}
+ return 3;
}
void unlock_mutex(struct Mutex* m)