1995/0109/port/taslock.c (diff list | history)

port/taslock.c on 1992/0222
1992/0222		#include "u.h"
1992/0321		#include "../port/lib.h"
1992/0222		#include "mem.h" #include "dat.h" #include "fns.h" #include "../port/error.h" void lock(Lock *l) {
1995/0108		int n; if(up) { n = up->inlock+2; up->inlock = n; if(tas(&l->key) == 0) return; for(;;){ while(l->key) if(conf.nproc == 1) { up->yield = 1; sched(); } up->inlock = n; if(tas(&l->key) == 0) return; } }
1993/1204		if(tas(&l->key) == 0) return;
1993/0830		for(;;){
1994/0808		while(l->key) ;
1993/0830		if(tas(&l->key) == 0)
1992/0222		return; } }
1995/0109		int canlock(Lock *l)
1994/0322		{
1995/0109		int n;
1994/0323
1995/0109		if(up) { n = up->inlock; up->inlock = n+2; if(tas(&l->key)) { up->inlock = n; return 0;
1994/0323		}
1995/0109		return 1;
1994/0322		}
1992/0222		if(tas(&l->key)) return 0; return 1; } void unlock(Lock *l) {
1995/0108		int n; if(up) { n = up->inlock-2; if(n < 0) n = 0; up->inlock = n; }
1995/0109		l->key = 0;
1994/0322		} void
1995/0109		ilock(Lock *l) { ulong sr; sr = splhi(); lock(l); l->sr = sr; } void
1994/0322		iunlock(Lock *l) { ulong sr; sr = l->sr;
1995/0109		unlock(l);
1994/0322		splx(sr);
1992/0222		}