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atomics: Provide atomic_add_negative() variants

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atomic_add_negative() does not provide the relaxed/acquire/release
variants.

Provide them in preparation for a new scalable reference count algorithm.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20230323102800.101763813@linutronix.de
This commit is contained in:
Thomas Gleixner 2023-03-23 21:55:30 +01:00 committed by Peter Zijlstra
parent fe15c26ee2
commit e5ab9eff46
5 changed files with 309 additions and 18 deletions
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208
include/linux/atomic/atomic-arch-fallback.h
View File

@ -1208,15 +1208,21 @@ arch_atomic_inc_and_test(atomic_t *v)
#define arch_atomic_inc_and_test arch_atomic_inc_and_test
#endif
#ifndef arch_atomic_add_negative_relaxed
#ifdef arch_atomic_add_negative
#define arch_atomic_add_negative_acquire arch_atomic_add_negative
#define arch_atomic_add_negative_release arch_atomic_add_negative
#define arch_atomic_add_negative_relaxed arch_atomic_add_negative
#endif /* arch_atomic_add_negative */
#ifndef arch_atomic_add_negative
/**
* arch_atomic_add_negative - add and test if negative
* arch_atomic_add_negative - Add and test if negative
* @i: integer value to add
* @v: pointer of type atomic_t
*
* Atomically adds @i to @v and returns true
* if the result is negative, or false when
* result is greater than or equal to zero.
* Atomically adds @i to @v and returns true if the result is negative,
* or false when the result is greater than or equal to zero.
*/
static __always_inline bool
arch_atomic_add_negative(int i, atomic_t *v)
@ -1226,6 +1232,95 @@ arch_atomic_add_negative(int i, atomic_t *v)
#define arch_atomic_add_negative arch_atomic_add_negative
#endif
#ifndef arch_atomic_add_negative_acquire
/**
* arch_atomic_add_negative_acquire - Add and test if negative
* @i: integer value to add
* @v: pointer of type atomic_t
*
* Atomically adds @i to @v and returns true if the result is negative,
* or false when the result is greater than or equal to zero.
*/
static __always_inline bool
arch_atomic_add_negative_acquire(int i, atomic_t *v)
{
return arch_atomic_add_return_acquire(i, v) < 0;
}
#define arch_atomic_add_negative_acquire arch_atomic_add_negative_acquire
#endif
#ifndef arch_atomic_add_negative_release
/**
* arch_atomic_add_negative_release - Add and test if negative
* @i: integer value to add
* @v: pointer of type atomic_t
*
* Atomically adds @i to @v and returns true if the result is negative,
* or false when the result is greater than or equal to zero.
*/
static __always_inline bool
arch_atomic_add_negative_release(int i, atomic_t *v)
{
return arch_atomic_add_return_release(i, v) < 0;
}
#define arch_atomic_add_negative_release arch_atomic_add_negative_release
#endif
#ifndef arch_atomic_add_negative_relaxed
/**
* arch_atomic_add_negative_relaxed - Add and test if negative
* @i: integer value to add
* @v: pointer of type atomic_t
*
* Atomically adds @i to @v and returns true if the result is negative,
* or false when the result is greater than or equal to zero.
*/
static __always_inline bool
arch_atomic_add_negative_relaxed(int i, atomic_t *v)
{
return arch_atomic_add_return_relaxed(i, v) < 0;
}
#define arch_atomic_add_negative_relaxed arch_atomic_add_negative_relaxed
#endif
#else /* arch_atomic_add_negative_relaxed */
#ifndef arch_atomic_add_negative_acquire
static __always_inline bool
arch_atomic_add_negative_acquire(int i, atomic_t *v)
{
bool ret = arch_atomic_add_negative_relaxed(i, v);
__atomic_acquire_fence();
return ret;
}
#define arch_atomic_add_negative_acquire arch_atomic_add_negative_acquire
#endif
#ifndef arch_atomic_add_negative_release
static __always_inline bool
arch_atomic_add_negative_release(int i, atomic_t *v)
{
__atomic_release_fence();
return arch_atomic_add_negative_relaxed(i, v);
}
#define arch_atomic_add_negative_release arch_atomic_add_negative_release
#endif
#ifndef arch_atomic_add_negative
static __always_inline bool
arch_atomic_add_negative(int i, atomic_t *v)
{
bool ret;
__atomic_pre_full_fence();
ret = arch_atomic_add_negative_relaxed(i, v);
__atomic_post_full_fence();
return ret;
}
#define arch_atomic_add_negative arch_atomic_add_negative
#endif
#endif /* arch_atomic_add_negative_relaxed */
#ifndef arch_atomic_fetch_add_unless
/**
* arch_atomic_fetch_add_unless - add unless the number is already a given value
@ -2329,15 +2424,21 @@ arch_atomic64_inc_and_test(atomic64_t *v)
#define arch_atomic64_inc_and_test arch_atomic64_inc_and_test
#endif
#ifndef arch_atomic64_add_negative_relaxed
#ifdef arch_atomic64_add_negative
#define arch_atomic64_add_negative_acquire arch_atomic64_add_negative
#define arch_atomic64_add_negative_release arch_atomic64_add_negative
#define arch_atomic64_add_negative_relaxed arch_atomic64_add_negative
#endif /* arch_atomic64_add_negative */
#ifndef arch_atomic64_add_negative
/**
* arch_atomic64_add_negative - add and test if negative
* arch_atomic64_add_negative - Add and test if negative
* @i: integer value to add
* @v: pointer of type atomic64_t
*
* Atomically adds @i to @v and returns true
* if the result is negative, or false when
* result is greater than or equal to zero.
* Atomically adds @i to @v and returns true if the result is negative,
* or false when the result is greater than or equal to zero.
*/
static __always_inline bool
arch_atomic64_add_negative(s64 i, atomic64_t *v)
@ -2347,6 +2448,95 @@ arch_atomic64_add_negative(s64 i, atomic64_t *v)
#define arch_atomic64_add_negative arch_atomic64_add_negative
#endif
#ifndef arch_atomic64_add_negative_acquire
/**
* arch_atomic64_add_negative_acquire - Add and test if negative
* @i: integer value to add
* @v: pointer of type atomic64_t
*
* Atomically adds @i to @v and returns true if the result is negative,
* or false when the result is greater than or equal to zero.
*/
static __always_inline bool
arch_atomic64_add_negative_acquire(s64 i, atomic64_t *v)
{
return arch_atomic64_add_return_acquire(i, v) < 0;
}
#define arch_atomic64_add_negative_acquire arch_atomic64_add_negative_acquire
#endif
#ifndef arch_atomic64_add_negative_release
/**
* arch_atomic64_add_negative_release - Add and test if negative
* @i: integer value to add
* @v: pointer of type atomic64_t
*
* Atomically adds @i to @v and returns true if the result is negative,
* or false when the result is greater than or equal to zero.
*/
static __always_inline bool
arch_atomic64_add_negative_release(s64 i, atomic64_t *v)
{
return arch_atomic64_add_return_release(i, v) < 0;
}
#define arch_atomic64_add_negative_release arch_atomic64_add_negative_release
#endif
#ifndef arch_atomic64_add_negative_relaxed
/**
* arch_atomic64_add_negative_relaxed - Add and test if negative
* @i: integer value to add
* @v: pointer of type atomic64_t
*
* Atomically adds @i to @v and returns true if the result is negative,
* or false when the result is greater than or equal to zero.
*/
static __always_inline bool
arch_atomic64_add_negative_relaxed(s64 i, atomic64_t *v)
{
return arch_atomic64_add_return_relaxed(i, v) < 0;
}
#define arch_atomic64_add_negative_relaxed arch_atomic64_add_negative_relaxed
#endif
#else /* arch_atomic64_add_negative_relaxed */
#ifndef arch_atomic64_add_negative_acquire
static __always_inline bool
arch_atomic64_add_negative_acquire(s64 i, atomic64_t *v)
{
bool ret = arch_atomic64_add_negative_relaxed(i, v);
__atomic_acquire_fence();
return ret;
}
#define arch_atomic64_add_negative_acquire arch_atomic64_add_negative_acquire
#endif
#ifndef arch_atomic64_add_negative_release
static __always_inline bool
arch_atomic64_add_negative_release(s64 i, atomic64_t *v)
{
__atomic_release_fence();
return arch_atomic64_add_negative_relaxed(i, v);
}
#define arch_atomic64_add_negative_release arch_atomic64_add_negative_release
#endif
#ifndef arch_atomic64_add_negative
static __always_inline bool
arch_atomic64_add_negative(s64 i, atomic64_t *v)
{
bool ret;
__atomic_pre_full_fence();
ret = arch_atomic64_add_negative_relaxed(i, v);
__atomic_post_full_fence();
return ret;
}
#define arch_atomic64_add_negative arch_atomic64_add_negative
#endif
#endif /* arch_atomic64_add_negative_relaxed */
#ifndef arch_atomic64_fetch_add_unless
/**
* arch_atomic64_fetch_add_unless - add unless the number is already a given value
@ -2456,4 +2646,4 @@ arch_atomic64_dec_if_positive(atomic64_t *v)
#endif
#endif /* _LINUX_ATOMIC_FALLBACK_H */
// b5e87bdd5ede61470c29f7a7e4de781af3770f09
// 00071fffa021cec66f6290d706d69c91df87bade

68
include/linux/atomic/atomic-instrumented.h
View File

@ -592,6 +592,28 @@ atomic_add_negative(int i, atomic_t *v)
return arch_atomic_add_negative(i, v);
}
static __always_inline bool
atomic_add_negative_acquire(int i, atomic_t *v)
{
instrument_atomic_read_write(v, sizeof(*v));
return arch_atomic_add_negative_acquire(i, v);
}
static __always_inline bool
atomic_add_negative_release(int i, atomic_t *v)
{
kcsan_release();
instrument_atomic_read_write(v, sizeof(*v));
return arch_atomic_add_negative_release(i, v);
}
static __always_inline bool
atomic_add_negative_relaxed(int i, atomic_t *v)
{
instrument_atomic_read_write(v, sizeof(*v));
return arch_atomic_add_negative_relaxed(i, v);
}
static __always_inline int
atomic_fetch_add_unless(atomic_t *v, int a, int u)
{
@ -1211,6 +1233,28 @@ atomic64_add_negative(s64 i, atomic64_t *v)
return arch_atomic64_add_negative(i, v);
}
static __always_inline bool
atomic64_add_negative_acquire(s64 i, atomic64_t *v)
{
instrument_atomic_read_write(v, sizeof(*v));
return arch_atomic64_add_negative_acquire(i, v);
}
static __always_inline bool
atomic64_add_negative_release(s64 i, atomic64_t *v)
{
kcsan_release();
instrument_atomic_read_write(v, sizeof(*v));
return arch_atomic64_add_negative_release(i, v);
}
static __always_inline bool
atomic64_add_negative_relaxed(s64 i, atomic64_t *v)
{
instrument_atomic_read_write(v, sizeof(*v));
return arch_atomic64_add_negative_relaxed(i, v);
}
static __always_inline s64
atomic64_fetch_add_unless(atomic64_t *v, s64 a, s64 u)
{
@ -1830,6 +1874,28 @@ atomic_long_add_negative(long i, atomic_long_t *v)
return arch_atomic_long_add_negative(i, v);
}
static __always_inline bool
atomic_long_add_negative_acquire(long i, atomic_long_t *v)
{
instrument_atomic_read_write(v, sizeof(*v));
return arch_atomic_long_add_negative_acquire(i, v);
}
static __always_inline bool
atomic_long_add_negative_release(long i, atomic_long_t *v)
{
kcsan_release();
instrument_atomic_read_write(v, sizeof(*v));
return arch_atomic_long_add_negative_release(i, v);
}
static __always_inline bool
atomic_long_add_negative_relaxed(long i, atomic_long_t *v)
{
instrument_atomic_read_write(v, sizeof(*v));
return arch_atomic_long_add_negative_relaxed(i, v);
}
static __always_inline long
atomic_long_fetch_add_unless(atomic_long_t *v, long a, long u)
{
@ -2083,4 +2149,4 @@ atomic_long_dec_if_positive(atomic_long_t *v)
})
#endif /* _LINUX_ATOMIC_INSTRUMENTED_H */
// 764f741eb77a7ad565dc8d99ce2837d5542e8aee
// 1b485de9cbaa4900de59e14ee2084357eaeb1c3a

38
include/linux/atomic/atomic-long.h
View File

@ -479,6 +479,24 @@ arch_atomic_long_add_negative(long i, atomic_long_t *v)
return arch_atomic64_add_negative(i, v);
}
static __always_inline bool
arch_atomic_long_add_negative_acquire(long i, atomic_long_t *v)
{
return arch_atomic64_add_negative_acquire(i, v);
}
static __always_inline bool
arch_atomic_long_add_negative_release(long i, atomic_long_t *v)
{
return arch_atomic64_add_negative_release(i, v);
}
static __always_inline bool
arch_atomic_long_add_negative_relaxed(long i, atomic_long_t *v)
{
return arch_atomic64_add_negative_relaxed(i, v);
}
static __always_inline long
arch_atomic_long_fetch_add_unless(atomic_long_t *v, long a, long u)
{
@ -973,6 +991,24 @@ arch_atomic_long_add_negative(long i, atomic_long_t *v)
return arch_atomic_add_negative(i, v);
}
static __always_inline bool
arch_atomic_long_add_negative_acquire(long i, atomic_long_t *v)
{
return arch_atomic_add_negative_acquire(i, v);
}
static __always_inline bool
arch_atomic_long_add_negative_release(long i, atomic_long_t *v)
{
return arch_atomic_add_negative_release(i, v);
}
static __always_inline bool
arch_atomic_long_add_negative_relaxed(long i, atomic_long_t *v)
{
return arch_atomic_add_negative_relaxed(i, v);
}
static __always_inline long
arch_atomic_long_fetch_add_unless(atomic_long_t *v, long a, long u)
{
@ -1011,4 +1047,4 @@ arch_atomic_long_dec_if_positive(atomic_long_t *v)
#endif /* CONFIG_64BIT */
#endif /* _LINUX_ATOMIC_LONG_H */
// e8f0e08ff072b74d180eabe2ad001282b38c2c88
// a194c07d7d2f4b0e178d3c118c919775d5d65f50

2
scripts/atomic/atomics.tbl
View File

@ -33,7 +33,7 @@ try_cmpxchg B v p:old i:new
sub_and_test b i v
dec_and_test b v
inc_and_test b v
add_negative b i v
add_negative B i v
add_unless fb v i:a i:u
inc_not_zero b v
inc_unless_negative b v

11
scripts/atomic/fallbacks/add_negative
View File

@ -1,16 +1,15 @@
cat <<EOF
/**
* arch_${atomic}_add_negative - add and test if negative
* arch_${atomic}_add_negative${order} - Add and test if negative
* @i: integer value to add
* @v: pointer of type ${atomic}_t
*
* Atomically adds @i to @v and returns true
* if the result is negative, or false when
* result is greater than or equal to zero.
* Atomically adds @i to @v and returns true if the result is negative,
* or false when the result is greater than or equal to zero.
*/
static __always_inline bool
arch_${atomic}_add_negative(${int} i, ${atomic}_t *v)
arch_${atomic}_add_negative${order}(${int} i, ${atomic}_t *v)
{
return arch_${atomic}_add_return(i, v) < 0;
return arch_${atomic}_add_return${order}(i, v) < 0;
}
EOF