From 5e0eb67974e88dbaded765278a3ffe7af33e3b22 Mon Sep 17 00:00:00 2001 From: Uros Bizjak Date: Mon, 31 Jul 2023 10:42:23 +0200 Subject: 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: Uros Bizjak Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20230731084458.28096-1-ubizjak@gmail.com --- arch/alpha/include/asm/local.h | 33 ++++++++++++++++----------------- arch/loongarch/include/asm/local.h | 27 ++++++++++++++++----------- arch/mips/include/asm/local.h | 27 ++++++++++++++++----------- arch/powerpc/include/asm/local.h | 12 ++++++------ arch/x86/include/asm/local.h | 33 ++++++++++++++++----------------- 5 files changed, 70 insertions(+), 62 deletions(-) diff --git a/arch/alpha/include/asm/local.h b/arch/alpha/include/asm/local.h index 0fcaad642cc3..88eb398947a5 100644 --- a/arch/alpha/include/asm/local.h +++ b/arch/alpha/include/asm/local.h @@ -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) diff --git a/arch/loongarch/include/asm/local.h b/arch/loongarch/include/asm/local.h index c49675852bdc..f53ea653af76 100644 --- a/arch/loongarch/include/asm/local.h +++ b/arch/loongarch/include/asm/local.h @@ -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)) diff --git a/arch/mips/include/asm/local.h b/arch/mips/include/asm/local.h index e6ae3df0349d..86fc24022242 100644 --- a/arch/mips/include/asm/local.h +++ b/arch/mips/include/asm/local.h @@ -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)) diff --git a/arch/powerpc/include/asm/local.h b/arch/powerpc/include/asm/local.h index 45492fb5bf22..ec6ced6d7ced 100644 --- a/arch/powerpc/include/asm/local.h +++ b/arch/powerpc/include/asm/local.h @@ -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); diff --git a/arch/x86/include/asm/local.h b/arch/x86/include/asm/local.h index 635132a12778..73dba8b94443 100644 --- a/arch/x86/include/asm/local.h +++ b/arch/x86/include/asm/local.h @@ -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. -- cgit