[ARM] 5067/1: _raw_write_can_lock macro bugfix

srplsnh · Russell King · commit 1e5c59460777 · 2008-06-02T13:44:17.000+01:00
The current __raw_write_can_lock macro tests whether the lock can be
locked by checking if it is equal to 0x80000000, whereas the lock
should be lockable if its value is 0 i.e. unlocked state is
represented by 0. Hence the macro should test the value of lock
against 0 and not 0x80000000.

Signed-off-by: Surinder Pal Singh &lt;srplsnh@gmail.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
diff --git a/include/asm-arm/spinlock.h b/include/asm-arm/spinlock.h
@@ -142,7 +142,7 @@ static inline void __raw_write_unlock(raw_rwlock_t *rw)
 }
 
 /* write_can_lock - would write_trylock() succeed? */
-#define __raw_write_can_lock(x)		((x)->lock == 0x80000000)
+#define __raw_write_can_lock(x)		((x)->lock == 0)
 
 /*
  * Read locks are a bit more hairy:

Original file line number	Diff line number	Diff line change
`@@ -142,7 +142,7 @@ static inline void __raw_write_unlock(raw_rwlock_t *rw)`
`142`	`142`	`}`
`143`	`143`
`144`	`144`	`/* write_can_lock - would write_trylock() succeed? */`
`145`		`-#define __raw_write_can_lock(x) ((x)->lock == 0x80000000)`
	`145`	`+#define __raw_write_can_lock(x) ((x)->lock == 0)`
`146`	`146`
`147`	`147`	`/*`
`148`	`148`	`* Read locks are a bit more hairy:`