Commit 5e0eb679 authored by Uros Bizjak's avatar Uros Bizjak Committed by Ingo Molnar
Browse files

locking/local, arch: Rewrite local_add_unless() as a static inline function 



Rewrite local_add_unless() as a static inline function with boolean
return value, similar to the arch_atomic_add_unless() arch fallbacks.

The function is currently unused.

Signed-off-by: default avatarUros Bizjak <ubizjak@gmail.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230731084458.28096-1-ubizjak@gmail.com
parent 8788c6c2

arch/alpha/include/asm/local.h

+16 −17
Original line number Diff line number Diff line
@@ -65,28 +65,27 @@ static __inline__ bool local_try_cmpxchg(local_t *l, long *old, long new) 
#define local_xchg(l, n) (xchg_local(&((l)->a.counter), (n)))



/**

 * local_add_unless - add unless the number is a given value

 * local_add_unless - add unless the number is already a given value

 * @l: pointer of type local_t

 * @a: the amount to add to l...

 * @u: ...unless l is equal to u.

 *

 * Atomically adds @a to @l, so long as it was not @u.

 * Returns non-zero if @l was not @u, and zero otherwise.

 * Atomically adds @a to @l, if @v was not already @u.

 * Returns true if the addition was done.

 */

#define local_add_unless(l, a, u)				\

({								\

	long c, old;						\

	c = local_read(l);					\

	for (;;) {						\

		if (unlikely(c == (u)))				\

			break;					\

		old = local_cmpxchg((l), c, c + (a));	\

		if (likely(old == c))				\

			break;					\

		c = old;					\

	}							\

	c != (u);						\

})

static __inline__ bool

local_add_unless(local_t *l, long a, long u)

{

	long c = local_read(l);



	do {

		if (unlikely(c == u))

			return false;

	} while (!local_try_cmpxchg(l, &c, c + a));



	return true;

}



#define local_inc_not_zero(l) local_add_unless((l), 1, 0)



#define local_add_negative(a, l) (local_add_return((a), (l)) < 0)

arch/loongarch/include/asm/local.h

+16 −11
Original line number Diff line number Diff line
@@ -70,22 +70,27 @@ static inline bool local_try_cmpxchg(local_t *l, long *old, long new) 
#define local_xchg(l, n) (atomic_long_xchg((&(l)->a), (n)))



/**

 * local_add_unless - add unless the number is a given value

 * local_add_unless - add unless the number is already a given value

 * @l: pointer of type local_t

 * @a: the amount to add to l...

 * @u: ...unless l is equal to u.

 *

 * Atomically adds @a to @l, so long as it was not @u.

 * Returns non-zero if @l was not @u, and zero otherwise.

 * Atomically adds @a to @l, if @v was not already @u.

 * Returns true if the addition was done.

 */

#define local_add_unless(l, a, u)				\

({								\

	long c, old;						\

	c = local_read(l);					\

	while (c != (u) && (old = local_cmpxchg((l), c, c + (a))) != c) \

		c = old;					\

	c != (u);						\

})

static inline bool

local_add_unless(local_t *l, long a, long u)

{

	long c = local_read(l);



	do {

		if (unlikely(c == u))

			return false;

	} while (!local_try_cmpxchg(l, &c, c + a));



	return true;

}



#define local_inc_not_zero(l) local_add_unless((l), 1, 0)



#define local_dec_return(l) local_sub_return(1, (l))

arch/mips/include/asm/local.h

+16 −11
Original line number Diff line number Diff line
@@ -108,22 +108,27 @@ static __inline__ bool local_try_cmpxchg(local_t *l, long *old, long new) 
#define local_xchg(l, n) (atomic_long_xchg((&(l)->a), (n)))



/**

 * local_add_unless - add unless the number is a given value

 * local_add_unless - add unless the number is already a given value

 * @l: pointer of type local_t

 * @a: the amount to add to l...

 * @u: ...unless l is equal to u.

 *

 * Atomically adds @a to @l, so long as it was not @u.

 * Returns non-zero if @l was not @u, and zero otherwise.

 * Atomically adds @a to @l, if @v was not already @u.

 * Returns true if the addition was done.

 */

#define local_add_unless(l, a, u)				\

({								\

	long c, old;						\

	c = local_read(l);					\

	while (c != (u) && (old = local_cmpxchg((l), c, c + (a))) != c) \

		c = old;					\

	c != (u);						\

})

static __inline__ bool

local_add_unless(local_t *l, long a, long u)

{

	long c = local_read(l);



	do {

		if (unlikely(c == u))

			return false;

	} while (!local_try_cmpxchg(l, &c, c + a));



	return true;

}



#define local_inc_not_zero(l) local_add_unless((l), 1, 0)



#define local_dec_return(l) local_sub_return(1, (l))

arch/powerpc/include/asm/local.h

+6 −6
Original line number Diff line number Diff line
@@ -115,23 +115,23 @@ static __inline__ long local_xchg(local_t *l, long n) 
}



/**

 * local_add_unless - add unless the number is a given value

 * local_add_unless - add unless the number is already a given value

 * @l: pointer of type local_t

 * @a: the amount to add to v...

 * @u: ...unless v is equal to u.

 *

 * Atomically adds @a to @l, so long as it was not @u.

 * Returns non-zero if @l was not @u, and zero otherwise.

 * Atomically adds @a to @l, if @v was not already @u.

 * Returns true if the addition was done.

 */

static __inline__ int local_add_unless(local_t *l, long a, long u)

static __inline__ bool local_add_unless(local_t *l, long a, long u)

{

	unsigned long flags;

	int ret = 0;

	bool ret = false;



	powerpc_local_irq_pmu_save(flags);

	if (l->v != u) {

		l->v += a;

		ret = 1;

		ret = true;

	}

	powerpc_local_irq_pmu_restore(flags);

arch/x86/include/asm/local.h

+16 −17
Original line number Diff line number Diff line
@@ -135,28 +135,27 @@ static inline bool local_try_cmpxchg(local_t *l, long *old, long new) 
#define local_xchg(l, n) (xchg(&((l)->a.counter), (n)))



/**

 * local_add_unless - add unless the number is a given value

 * local_add_unless - add unless the number is already a given value

 * @l: pointer of type local_t

 * @a: the amount to add to l...

 * @u: ...unless l is equal to u.

 *

 * Atomically adds @a to @l, so long as it was not @u.

 * Returns non-zero if @l was not @u, and zero otherwise.

 * Atomically adds @a to @l, if @v was not already @u.

 * Returns true if the addition was done.

 */

#define local_add_unless(l, a, u)				\

({								\

	long c, old;						\

	c = local_read((l));					\

	for (;;) {						\

		if (unlikely(c == (u)))				\

			break;					\

		old = local_cmpxchg((l), c, c + (a));		\

		if (likely(old == c))				\

			break;					\

		c = old;					\

	}							\

	c != (u);						\

})

static __always_inline bool

local_add_unless(local_t *l, long a, long u)

{

	long c = local_read(l);



	do {

		if (unlikely(c == u))

			return false;

	} while (!local_try_cmpxchg(l, &c, c + a));



	return true;

}



#define local_inc_not_zero(l) local_add_unless((l), 1, 0)



/* On x86_32, these are no better than the atomic variants.