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Enable pop_off and push_off in spinlocks

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This commit is contained in:
Imbus 2025-09-02 04:30:00 +02:00
parent 595ae0a8e2
commit e15b705eda
1 changed files with 9 additions and 8 deletions
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17
kern/libkern/spinlock.c
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@ -67,7 +67,7 @@ uint32_t pop_off(void) {
PANIC("pop_off - interruptible"); PANIC("pop_off - interruptible");
if (cpu->noff < 1) if (cpu->noff < 1)
PANIC("pop_off"); PANIC("pop_off when cpu->noff < 1");
cpu->noff -= 1; cpu->noff -= 1;
@ -89,8 +89,8 @@ __attribute__((warn_unused_result)) bool spin_trylock(spinlock_t *l) {
} }
void spin_unlock(spinlock_t *l) { void spin_unlock(spinlock_t *l) {
// if (!spin_is_holding(l)) if (!spin_is_holding(l))
// panic("spin_unlock"); PANIC("Unlocking a spinlock that is not held by the locking cpu!");
l->cpu = 0; l->cpu = 0;
@ -98,10 +98,10 @@ void spin_unlock(spinlock_t *l) {
uint32_t dummy; uint32_t dummy;
__asm__ volatile("amoswap.w.rl %0, %2, (%1)\n" : "=&r"(dummy) : "r"(&l->v), "r"(0u) : "memory"); __asm__ volatile("amoswap.w.rl %0, %2, (%1)\n" : "=&r"(dummy) : "r"(&l->v), "r"(0u) : "memory");
// __sync_synchronize(); // No loads/stores after this point __sync_synchronize(); // No loads/stores after this point
// __sync_lock_release(&lk->locked); // Essentially lk->locked = 0 // __sync_lock_release(&lk->locked); // Essentially lk->locked = 0
// pop_off(); pop_off();
} }
/** /**
@ -110,8 +110,11 @@ void spin_unlock(spinlock_t *l) {
void spin_lock(spinlock_t *l) { void spin_lock(spinlock_t *l) {
uint32_t backoff = 1; uint32_t backoff = 1;
for (;;) { for (;;) {
if (spin_trylock(l)) if (spin_trylock(l)) {
l->cpu = mycpu();
push_off();
return; return;
}
while (__atomic_load_n(&l->v, __ATOMIC_RELAXED) != 0) { while (__atomic_load_n(&l->v, __ATOMIC_RELAXED) != 0) {
for (uint32_t i = 0; i < backoff; ++i) for (uint32_t i = 0; i < backoff; ++i)
@ -120,8 +123,6 @@ void spin_lock(spinlock_t *l) {
backoff <<= 1; backoff <<= 1;
} }
} }
l->cpu = mycpu();
} }
/** /**