Commit ee25e96f authored by Oleg Nesterov's avatar Oleg Nesterov Committed by Linus Torvalds
Browse files

[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: default avatarOleg Nesterov <oleg@tv-sign.ru>
Acked-by: default avatarIngo Molnar <mingo@elte.hu>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent eb8782ef

kernel/spinlock.c

+4 −5
Original line number Diff line number Diff line
@@ -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_irqsave(locktype##_t *lock) \ 
{									\

	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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