atomic: Export fetch_or()

Export fetch_or() that's implemented and used internally by the
scheduler. We are going to use it for NO_HZ so make it generally
available.

Reviewed-by: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
This commit is contained in:
Frederic Weisbecker 2015-08-11 18:03:23 +02:00
parent 36f90b0a2d
commit 5fd7a09cfb
2 changed files with 21 additions and 14 deletions

View file

@ -548,6 +548,27 @@ static inline int atomic_dec_if_positive(atomic_t *v)
}
#endif
/**
* fetch_or - perform *ptr |= mask and return old value of *ptr
* @ptr: pointer to value
* @mask: mask to OR on the value
*
* cmpxchg based fetch_or, macro so it works for different integer types
*/
#ifndef fetch_or
#define fetch_or(ptr, mask) \
({ typeof(*(ptr)) __old, __val = *(ptr); \
for (;;) { \
__old = cmpxchg((ptr), __val, __val | (mask)); \
if (__old == __val) \
break; \
__val = __old; \
} \
__old; \
})
#endif
#ifdef CONFIG_GENERIC_ATOMIC64
#include <asm-generic/atomic64.h>
#endif

View file

@ -453,20 +453,6 @@ static inline void init_hrtick(void)
}
#endif /* CONFIG_SCHED_HRTICK */
/*
* cmpxchg based fetch_or, macro so it works for different integer types
*/
#define fetch_or(ptr, val) \
({ typeof(*(ptr)) __old, __val = *(ptr); \
for (;;) { \
__old = cmpxchg((ptr), __val, __val | (val)); \
if (__old == __val) \
break; \
__val = __old; \
} \
__old; \
})
#if defined(CONFIG_SMP) && defined(TIF_POLLING_NRFLAG)
/*
* Atomically set TIF_NEED_RESCHED and test for TIF_POLLING_NRFLAG,