Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 5fd7a09c authored by Frederic Weisbecker's avatar Frederic Weisbecker
Browse files

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: default avatarChris 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: default avatarFrederic Weisbecker <fweisbec@gmail.com>
parent 36f90b0a

include/linux/atomic.h

+21 −0
Original line number Diff line number Diff line
@@ -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

kernel/sched/core.c

+0 −14
Original line number Diff line number Diff line
@@ -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,