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#include "types.h"
#include "defs.h"
#include "x86.h"
#include "mmu.h"
#include "param.h"
#include "proc.h"
#include "spinlock.h"
#define DEBUG 0
extern int use_console_lock;
int getcallerpc(void *v) {
return ((int*)v)[-1];
}
void
acquire1(struct spinlock * lock, struct proc *cp)
{
if(DEBUG) cprintf("cpu%d: acquiring at %x\n", cpu(), getcallerpc(&lock));
cli();
while ( cmpxchg(0, 1, &lock->locked) == 1 ) { ; }
lock->locker_pc = getcallerpc(&lock);
if(cp)
cp->locks += 1;
if(DEBUG) cprintf("cpu%d: acquired at %x\n", cpu(), getcallerpc(&lock));
}
void
release1(struct spinlock * lock, struct proc *cp)
{
if(DEBUG) cprintf ("cpu%d: releasing at %x\n", cpu(), getcallerpc(&lock));
if(lock->locked != 1)
panic("release");
if(cp)
cp->locks -= 1;
cmpxchg(1, 0, &lock->locked);
sti();
}
void
acquire(struct spinlock *lock)
{
acquire1(lock, curproc[cpu()]);
}
void
release(struct spinlock *lock)
{
release1(lock, curproc[cpu()]);
}
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