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spinlock: rename parameter lock -> lk

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This commit is contained in:
Russ Cox 2009-07-11 19:26:51 -07:00
parent b8912d999f
commit b121486c3f
1 changed files with 15 additions and 15 deletions
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30
spinlock.c
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@ -9,11 +9,11 @@
#include "spinlock.h"
void
initlock(struct spinlock *lock, char *name)
initlock(struct spinlock *lk, char *name)
{
lock->name = name;
lock->locked = 0;
lock->cpu = 0xffffffff;
lk->name = name;
lk->locked = 0;
lk->cpu = 0xffffffff;
}
// Acquire the lock.
@ -21,35 +21,35 @@ initlock(struct spinlock *lock, char *name)
// Holding a lock for a long time may cause
// other CPUs to waste time spinning to acquire it.
void
acquire(struct spinlock *lock)
acquire(struct spinlock *lk)
{
pushcli();
if(holding(lock))
if(holding(lk))
panic("acquire");
// The xchg is atomic.
// It also serializes, so that reads after acquire are not
// reordered before it.
while(xchg(&lock->locked, 1) == 1)
// reordered before it.
while(xchg(&lk->locked, 1) != 0)
;
// Record info about lock acquisition for debugging.
// The +10 is only so that we can tell the difference
// between forgetting to initialize lock->cpu
// and holding a lock on cpu 0.
lock->cpu = cpu() + 10;
getcallerpcs(&lock, lock->pcs);
lk->cpu = cpu() + 10;
getcallerpcs(&lk, lk->pcs);
}
// Release the lock.
void
release(struct spinlock *lock)
release(struct spinlock *lk)
{
if(!holding(lock))
if(!holding(lk))
panic("release");
lock->pcs[0] = 0;
lock->cpu = 0xffffffff;
lk->pcs[0] = 0;
lk->cpu = 0xffffffff;
// The xchg serializes, so that reads before release are
// not reordered after it. The 1996 PentiumPro manual (Volume 3,
@ -60,7 +60,7 @@ release(struct spinlock *lock)
// after a store. So lock->locked = 0 would work here.
// The xchg being asm volatile ensures gcc emits it after
// the above assignments (and after the critical section).
xchg(&lock->locked, 0);
xchg(&lk->locked, 0);
popcli();
}