[PATCH] BUILD_LOCK_OPS: cleanup preempt_disable() usage

This patch changes the code from:

preempt_disable();
for (;;) {
...
preempt_disable();
}
to:
for (;;) {
preempt_disable();
...
}

which seems more clean to me and saves a couple of bytes for
each function.

Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>

--- 2.6.15/kernel/spinlock.c~ 2005-09-17 18:57:30.000000000 +0400
+++ 2.6.15/kernel/spinlock.c 2006-01-19 19:57:42.000000000 +0300
@@ -179,16 +179,16 @@ EXPORT_SYMBOL(_write_lock);
#define BUILD_LOCK_OPS(op, locktype) \
void __lockfunc _##op##_lock(locktype##_t *lock) \
{ \
- preempt_disable(); \
for (;;) { \
+ preempt_disable(); \
if (likely(_raw_##op##_trylock(lock))) \
break; \
preempt_enable(); \
+ \
if (!(lock)->break_lock) \
(lock)->break_lock = 1; \
while (!op##_can_lock(lock) && (lock)->break_lock) \
cpu_relax(); \
- preempt_disable(); \
} \
(lock)->break_lock = 0; \
} \
@@ -199,19 +199,18 @@ unsigned long __lockfunc _##op##_lock_ir
{ \
unsigned long flags; \
\
- preempt_disable(); \
for (;;) { \
+ preempt_disable(); \
local_irq_save(flags); \
if (likely(_raw_##op##_trylock(lock))) \
break; \
local_irq_restore(flags); \
- \
preempt_enable(); \
+ \
if (!(lock)->break_lock) \
(lock)->break_lock = 1; \
while (!op##_can_lock(lock) && (lock)->break_lock) \
cpu_relax(); \
- preempt_disable(); \
} \
(lock)->break_lock = 0; \
return flags; \
-
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