forked from mit-pdos/xv6-public
/
sleeplock.c
45 lines (39 loc) · 807 Bytes
/
sleeplock.c
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// Sleeping locks
#include "types.h"
#include "defs.h"
#include "param.h"
#include "x86.h"
#include "memlayout.h"
#include "mmu.h"
#include "proc.h"
#include "spinlock.h"
#include "sleeplock.h"
void initsleeplock(struct sleeplock *lk, char *name) {
initlock(&lk->lk, "sleep lock");
lk->name = name;
lk->locked = 0;
lk->pid = 0;
}
void acquiresleep(struct sleeplock *lk) {
acquire(&lk->lk);
while (lk->locked) {
sleep(lk, &lk->lk);
}
lk->locked = 1;
lk->pid = myproc()->pid;
release(&lk->lk);
}
void releasesleep(struct sleeplock *lk) {
acquire(&lk->lk);
lk->locked = 0;
lk->pid = 0;
wakeup(lk);
release(&lk->lk);
}
int holdingsleep(struct sleeplock *lk) {
int r;
acquire(&lk->lk);
r = lk->locked && (lk->pid == myproc()->pid);
release(&lk->lk);
return r;
}