2011-07-27 03:09:08 +04:00
|
|
|
/* Atomic operations usable in machine independent code */
|
2010-11-12 01:05:08 +03:00
|
|
|
#ifndef _LINUX_ATOMIC_H
|
|
|
|
#define _LINUX_ATOMIC_H
|
|
|
|
#include <asm/atomic.h>
|
locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
Whilst porting the generic qrwlock code over to arm64, it became
apparent that any portable locking code needs finer-grained control of
the memory-ordering guarantees provided by our atomic routines.
In particular: xchg, cmpxchg, {add,sub}_return are often used in
situations where full barrier semantics (currently the only option
available) are not required. For example, when a reader increments a
reader count to obtain a lock, checking the old value to see if a writer
was present, only acquire semantics are strictly needed.
This patch introduces three new ordering semantics for these operations:
- *_relaxed: No ordering guarantees. This is similar to what we have
already for the non-return atomics (e.g. atomic_add).
- *_acquire: ACQUIRE semantics, similar to smp_load_acquire.
- *_release: RELEASE semantics, similar to smp_store_release.
In memory-ordering speak, this means that the acquire/release semantics
are RCpc as opposed to RCsc. Consequently a RELEASE followed by an
ACQUIRE does not imply a full barrier, as already documented in
memory-barriers.txt.
Currently, all the new macros are conditionally mapped to the full-mb
variants, however if the *_relaxed version is provided by the
architecture, then the acquire/release variants are constructed by
supplementing the relaxed routine with an explicit barrier.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman.Long@hp.com
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1438880084-18856-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-06 19:54:37 +03:00
|
|
|
#include <asm/barrier.h>
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Relaxed variants of xchg, cmpxchg and some atomic operations.
|
|
|
|
*
|
|
|
|
* We support four variants:
|
|
|
|
*
|
|
|
|
* - Fully ordered: The default implementation, no suffix required.
|
|
|
|
* - Acquire: Provides ACQUIRE semantics, _acquire suffix.
|
|
|
|
* - Release: Provides RELEASE semantics, _release suffix.
|
|
|
|
* - Relaxed: No ordering guarantees, _relaxed suffix.
|
|
|
|
*
|
|
|
|
* For compound atomics performing both a load and a store, ACQUIRE
|
|
|
|
* semantics apply only to the load and RELEASE semantics only to the
|
|
|
|
* store portion of the operation. Note that a failed cmpxchg_acquire
|
|
|
|
* does -not- imply any memory ordering constraints.
|
|
|
|
*
|
|
|
|
* See Documentation/memory-barriers.txt for ACQUIRE/RELEASE definitions.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#ifndef atomic_read_acquire
|
|
|
|
#define atomic_read_acquire(v) smp_load_acquire(&(v)->counter)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_set_release
|
|
|
|
#define atomic_set_release(v, i) smp_store_release(&(v)->counter, (i))
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/*
|
|
|
|
* The idea here is to build acquire/release variants by adding explicit
|
|
|
|
* barriers on top of the relaxed variant. In the case where the relaxed
|
|
|
|
* variant is already fully ordered, no additional barriers are needed.
|
2015-12-15 17:24:14 +03:00
|
|
|
*
|
|
|
|
* Besides, if an arch has a special barrier for acquire/release, it could
|
|
|
|
* implement its own __atomic_op_* and use the same framework for building
|
|
|
|
* variants
|
locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
Whilst porting the generic qrwlock code over to arm64, it became
apparent that any portable locking code needs finer-grained control of
the memory-ordering guarantees provided by our atomic routines.
In particular: xchg, cmpxchg, {add,sub}_return are often used in
situations where full barrier semantics (currently the only option
available) are not required. For example, when a reader increments a
reader count to obtain a lock, checking the old value to see if a writer
was present, only acquire semantics are strictly needed.
This patch introduces three new ordering semantics for these operations:
- *_relaxed: No ordering guarantees. This is similar to what we have
already for the non-return atomics (e.g. atomic_add).
- *_acquire: ACQUIRE semantics, similar to smp_load_acquire.
- *_release: RELEASE semantics, similar to smp_store_release.
In memory-ordering speak, this means that the acquire/release semantics
are RCpc as opposed to RCsc. Consequently a RELEASE followed by an
ACQUIRE does not imply a full barrier, as already documented in
memory-barriers.txt.
Currently, all the new macros are conditionally mapped to the full-mb
variants, however if the *_relaxed version is provided by the
architecture, then the acquire/release variants are constructed by
supplementing the relaxed routine with an explicit barrier.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman.Long@hp.com
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1438880084-18856-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-06 19:54:37 +03:00
|
|
|
*/
|
2015-12-15 17:24:14 +03:00
|
|
|
#ifndef __atomic_op_acquire
|
locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
Whilst porting the generic qrwlock code over to arm64, it became
apparent that any portable locking code needs finer-grained control of
the memory-ordering guarantees provided by our atomic routines.
In particular: xchg, cmpxchg, {add,sub}_return are often used in
situations where full barrier semantics (currently the only option
available) are not required. For example, when a reader increments a
reader count to obtain a lock, checking the old value to see if a writer
was present, only acquire semantics are strictly needed.
This patch introduces three new ordering semantics for these operations:
- *_relaxed: No ordering guarantees. This is similar to what we have
already for the non-return atomics (e.g. atomic_add).
- *_acquire: ACQUIRE semantics, similar to smp_load_acquire.
- *_release: RELEASE semantics, similar to smp_store_release.
In memory-ordering speak, this means that the acquire/release semantics
are RCpc as opposed to RCsc. Consequently a RELEASE followed by an
ACQUIRE does not imply a full barrier, as already documented in
memory-barriers.txt.
Currently, all the new macros are conditionally mapped to the full-mb
variants, however if the *_relaxed version is provided by the
architecture, then the acquire/release variants are constructed by
supplementing the relaxed routine with an explicit barrier.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman.Long@hp.com
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1438880084-18856-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-06 19:54:37 +03:00
|
|
|
#define __atomic_op_acquire(op, args...) \
|
|
|
|
({ \
|
|
|
|
typeof(op##_relaxed(args)) __ret = op##_relaxed(args); \
|
|
|
|
smp_mb__after_atomic(); \
|
|
|
|
__ret; \
|
|
|
|
})
|
2015-12-15 17:24:14 +03:00
|
|
|
#endif
|
locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
Whilst porting the generic qrwlock code over to arm64, it became
apparent that any portable locking code needs finer-grained control of
the memory-ordering guarantees provided by our atomic routines.
In particular: xchg, cmpxchg, {add,sub}_return are often used in
situations where full barrier semantics (currently the only option
available) are not required. For example, when a reader increments a
reader count to obtain a lock, checking the old value to see if a writer
was present, only acquire semantics are strictly needed.
This patch introduces three new ordering semantics for these operations:
- *_relaxed: No ordering guarantees. This is similar to what we have
already for the non-return atomics (e.g. atomic_add).
- *_acquire: ACQUIRE semantics, similar to smp_load_acquire.
- *_release: RELEASE semantics, similar to smp_store_release.
In memory-ordering speak, this means that the acquire/release semantics
are RCpc as opposed to RCsc. Consequently a RELEASE followed by an
ACQUIRE does not imply a full barrier, as already documented in
memory-barriers.txt.
Currently, all the new macros are conditionally mapped to the full-mb
variants, however if the *_relaxed version is provided by the
architecture, then the acquire/release variants are constructed by
supplementing the relaxed routine with an explicit barrier.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman.Long@hp.com
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1438880084-18856-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-06 19:54:37 +03:00
|
|
|
|
2015-12-15 17:24:14 +03:00
|
|
|
#ifndef __atomic_op_release
|
locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
Whilst porting the generic qrwlock code over to arm64, it became
apparent that any portable locking code needs finer-grained control of
the memory-ordering guarantees provided by our atomic routines.
In particular: xchg, cmpxchg, {add,sub}_return are often used in
situations where full barrier semantics (currently the only option
available) are not required. For example, when a reader increments a
reader count to obtain a lock, checking the old value to see if a writer
was present, only acquire semantics are strictly needed.
This patch introduces three new ordering semantics for these operations:
- *_relaxed: No ordering guarantees. This is similar to what we have
already for the non-return atomics (e.g. atomic_add).
- *_acquire: ACQUIRE semantics, similar to smp_load_acquire.
- *_release: RELEASE semantics, similar to smp_store_release.
In memory-ordering speak, this means that the acquire/release semantics
are RCpc as opposed to RCsc. Consequently a RELEASE followed by an
ACQUIRE does not imply a full barrier, as already documented in
memory-barriers.txt.
Currently, all the new macros are conditionally mapped to the full-mb
variants, however if the *_relaxed version is provided by the
architecture, then the acquire/release variants are constructed by
supplementing the relaxed routine with an explicit barrier.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman.Long@hp.com
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1438880084-18856-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-06 19:54:37 +03:00
|
|
|
#define __atomic_op_release(op, args...) \
|
|
|
|
({ \
|
|
|
|
smp_mb__before_atomic(); \
|
|
|
|
op##_relaxed(args); \
|
|
|
|
})
|
2015-12-15 17:24:14 +03:00
|
|
|
#endif
|
locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
Whilst porting the generic qrwlock code over to arm64, it became
apparent that any portable locking code needs finer-grained control of
the memory-ordering guarantees provided by our atomic routines.
In particular: xchg, cmpxchg, {add,sub}_return are often used in
situations where full barrier semantics (currently the only option
available) are not required. For example, when a reader increments a
reader count to obtain a lock, checking the old value to see if a writer
was present, only acquire semantics are strictly needed.
This patch introduces three new ordering semantics for these operations:
- *_relaxed: No ordering guarantees. This is similar to what we have
already for the non-return atomics (e.g. atomic_add).
- *_acquire: ACQUIRE semantics, similar to smp_load_acquire.
- *_release: RELEASE semantics, similar to smp_store_release.
In memory-ordering speak, this means that the acquire/release semantics
are RCpc as opposed to RCsc. Consequently a RELEASE followed by an
ACQUIRE does not imply a full barrier, as already documented in
memory-barriers.txt.
Currently, all the new macros are conditionally mapped to the full-mb
variants, however if the *_relaxed version is provided by the
architecture, then the acquire/release variants are constructed by
supplementing the relaxed routine with an explicit barrier.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman.Long@hp.com
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1438880084-18856-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-06 19:54:37 +03:00
|
|
|
|
2015-12-15 17:24:14 +03:00
|
|
|
#ifndef __atomic_op_fence
|
locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
Whilst porting the generic qrwlock code over to arm64, it became
apparent that any portable locking code needs finer-grained control of
the memory-ordering guarantees provided by our atomic routines.
In particular: xchg, cmpxchg, {add,sub}_return are often used in
situations where full barrier semantics (currently the only option
available) are not required. For example, when a reader increments a
reader count to obtain a lock, checking the old value to see if a writer
was present, only acquire semantics are strictly needed.
This patch introduces three new ordering semantics for these operations:
- *_relaxed: No ordering guarantees. This is similar to what we have
already for the non-return atomics (e.g. atomic_add).
- *_acquire: ACQUIRE semantics, similar to smp_load_acquire.
- *_release: RELEASE semantics, similar to smp_store_release.
In memory-ordering speak, this means that the acquire/release semantics
are RCpc as opposed to RCsc. Consequently a RELEASE followed by an
ACQUIRE does not imply a full barrier, as already documented in
memory-barriers.txt.
Currently, all the new macros are conditionally mapped to the full-mb
variants, however if the *_relaxed version is provided by the
architecture, then the acquire/release variants are constructed by
supplementing the relaxed routine with an explicit barrier.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman.Long@hp.com
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1438880084-18856-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-06 19:54:37 +03:00
|
|
|
#define __atomic_op_fence(op, args...) \
|
|
|
|
({ \
|
|
|
|
typeof(op##_relaxed(args)) __ret; \
|
|
|
|
smp_mb__before_atomic(); \
|
|
|
|
__ret = op##_relaxed(args); \
|
|
|
|
smp_mb__after_atomic(); \
|
|
|
|
__ret; \
|
|
|
|
})
|
2015-12-15 17:24:14 +03:00
|
|
|
#endif
|
locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
Whilst porting the generic qrwlock code over to arm64, it became
apparent that any portable locking code needs finer-grained control of
the memory-ordering guarantees provided by our atomic routines.
In particular: xchg, cmpxchg, {add,sub}_return are often used in
situations where full barrier semantics (currently the only option
available) are not required. For example, when a reader increments a
reader count to obtain a lock, checking the old value to see if a writer
was present, only acquire semantics are strictly needed.
This patch introduces three new ordering semantics for these operations:
- *_relaxed: No ordering guarantees. This is similar to what we have
already for the non-return atomics (e.g. atomic_add).
- *_acquire: ACQUIRE semantics, similar to smp_load_acquire.
- *_release: RELEASE semantics, similar to smp_store_release.
In memory-ordering speak, this means that the acquire/release semantics
are RCpc as opposed to RCsc. Consequently a RELEASE followed by an
ACQUIRE does not imply a full barrier, as already documented in
memory-barriers.txt.
Currently, all the new macros are conditionally mapped to the full-mb
variants, however if the *_relaxed version is provided by the
architecture, then the acquire/release variants are constructed by
supplementing the relaxed routine with an explicit barrier.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman.Long@hp.com
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1438880084-18856-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-06 19:54:37 +03:00
|
|
|
|
|
|
|
/* atomic_add_return_relaxed */
|
|
|
|
#ifndef atomic_add_return_relaxed
|
|
|
|
#define atomic_add_return_relaxed atomic_add_return
|
|
|
|
#define atomic_add_return_acquire atomic_add_return
|
|
|
|
#define atomic_add_return_release atomic_add_return
|
|
|
|
|
|
|
|
#else /* atomic_add_return_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic_add_return_acquire
|
|
|
|
#define atomic_add_return_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic_add_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_add_return_release
|
|
|
|
#define atomic_add_return_release(...) \
|
|
|
|
__atomic_op_release(atomic_add_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_add_return
|
|
|
|
#define atomic_add_return(...) \
|
|
|
|
__atomic_op_fence(atomic_add_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic_add_return_relaxed */
|
|
|
|
|
2015-09-30 23:03:11 +03:00
|
|
|
/* atomic_inc_return_relaxed */
|
|
|
|
#ifndef atomic_inc_return_relaxed
|
|
|
|
#define atomic_inc_return_relaxed atomic_inc_return
|
|
|
|
#define atomic_inc_return_acquire atomic_inc_return
|
|
|
|
#define atomic_inc_return_release atomic_inc_return
|
|
|
|
|
|
|
|
#else /* atomic_inc_return_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic_inc_return_acquire
|
|
|
|
#define atomic_inc_return_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic_inc_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_inc_return_release
|
|
|
|
#define atomic_inc_return_release(...) \
|
|
|
|
__atomic_op_release(atomic_inc_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_inc_return
|
|
|
|
#define atomic_inc_return(...) \
|
|
|
|
__atomic_op_fence(atomic_inc_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic_inc_return_relaxed */
|
|
|
|
|
locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
Whilst porting the generic qrwlock code over to arm64, it became
apparent that any portable locking code needs finer-grained control of
the memory-ordering guarantees provided by our atomic routines.
In particular: xchg, cmpxchg, {add,sub}_return are often used in
situations where full barrier semantics (currently the only option
available) are not required. For example, when a reader increments a
reader count to obtain a lock, checking the old value to see if a writer
was present, only acquire semantics are strictly needed.
This patch introduces three new ordering semantics for these operations:
- *_relaxed: No ordering guarantees. This is similar to what we have
already for the non-return atomics (e.g. atomic_add).
- *_acquire: ACQUIRE semantics, similar to smp_load_acquire.
- *_release: RELEASE semantics, similar to smp_store_release.
In memory-ordering speak, this means that the acquire/release semantics
are RCpc as opposed to RCsc. Consequently a RELEASE followed by an
ACQUIRE does not imply a full barrier, as already documented in
memory-barriers.txt.
Currently, all the new macros are conditionally mapped to the full-mb
variants, however if the *_relaxed version is provided by the
architecture, then the acquire/release variants are constructed by
supplementing the relaxed routine with an explicit barrier.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman.Long@hp.com
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1438880084-18856-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-06 19:54:37 +03:00
|
|
|
/* atomic_sub_return_relaxed */
|
|
|
|
#ifndef atomic_sub_return_relaxed
|
|
|
|
#define atomic_sub_return_relaxed atomic_sub_return
|
|
|
|
#define atomic_sub_return_acquire atomic_sub_return
|
|
|
|
#define atomic_sub_return_release atomic_sub_return
|
|
|
|
|
|
|
|
#else /* atomic_sub_return_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic_sub_return_acquire
|
|
|
|
#define atomic_sub_return_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic_sub_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_sub_return_release
|
|
|
|
#define atomic_sub_return_release(...) \
|
|
|
|
__atomic_op_release(atomic_sub_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_sub_return
|
|
|
|
#define atomic_sub_return(...) \
|
|
|
|
__atomic_op_fence(atomic_sub_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic_sub_return_relaxed */
|
|
|
|
|
2015-09-30 23:03:11 +03:00
|
|
|
/* atomic_dec_return_relaxed */
|
|
|
|
#ifndef atomic_dec_return_relaxed
|
|
|
|
#define atomic_dec_return_relaxed atomic_dec_return
|
|
|
|
#define atomic_dec_return_acquire atomic_dec_return
|
|
|
|
#define atomic_dec_return_release atomic_dec_return
|
|
|
|
|
|
|
|
#else /* atomic_dec_return_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic_dec_return_acquire
|
|
|
|
#define atomic_dec_return_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic_dec_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_dec_return_release
|
|
|
|
#define atomic_dec_return_release(...) \
|
|
|
|
__atomic_op_release(atomic_dec_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_dec_return
|
|
|
|
#define atomic_dec_return(...) \
|
|
|
|
__atomic_op_fence(atomic_dec_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic_dec_return_relaxed */
|
|
|
|
|
locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
Now that all the architectures have implemented support for these new
atomic primitives add on the generic infrastructure to expose and use
it.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-18 01:54:38 +03:00
|
|
|
|
|
|
|
/* atomic_fetch_add_relaxed */
|
|
|
|
#ifndef atomic_fetch_add_relaxed
|
|
|
|
#define atomic_fetch_add_relaxed atomic_fetch_add
|
|
|
|
#define atomic_fetch_add_acquire atomic_fetch_add
|
|
|
|
#define atomic_fetch_add_release atomic_fetch_add
|
|
|
|
|
|
|
|
#else /* atomic_fetch_add_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_add_acquire
|
|
|
|
#define atomic_fetch_add_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic_fetch_add, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_add_release
|
|
|
|
#define atomic_fetch_add_release(...) \
|
|
|
|
__atomic_op_release(atomic_fetch_add, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_add
|
|
|
|
#define atomic_fetch_add(...) \
|
|
|
|
__atomic_op_fence(atomic_fetch_add, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic_fetch_add_relaxed */
|
|
|
|
|
2016-06-29 00:56:51 +03:00
|
|
|
/* atomic_fetch_inc_relaxed */
|
|
|
|
#ifndef atomic_fetch_inc_relaxed
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_inc
|
|
|
|
#define atomic_fetch_inc(v) atomic_fetch_add(1, (v))
|
|
|
|
#define atomic_fetch_inc_relaxed(v) atomic_fetch_add_relaxed(1, (v))
|
|
|
|
#define atomic_fetch_inc_acquire(v) atomic_fetch_add_acquire(1, (v))
|
|
|
|
#define atomic_fetch_inc_release(v) atomic_fetch_add_release(1, (v))
|
|
|
|
#else /* atomic_fetch_inc */
|
|
|
|
#define atomic_fetch_inc_relaxed atomic_fetch_inc
|
|
|
|
#define atomic_fetch_inc_acquire atomic_fetch_inc
|
|
|
|
#define atomic_fetch_inc_release atomic_fetch_inc
|
|
|
|
#endif /* atomic_fetch_inc */
|
|
|
|
|
|
|
|
#else /* atomic_fetch_inc_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_inc_acquire
|
|
|
|
#define atomic_fetch_inc_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic_fetch_inc, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_inc_release
|
|
|
|
#define atomic_fetch_inc_release(...) \
|
|
|
|
__atomic_op_release(atomic_fetch_inc, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_inc
|
|
|
|
#define atomic_fetch_inc(...) \
|
|
|
|
__atomic_op_fence(atomic_fetch_inc, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic_fetch_inc_relaxed */
|
|
|
|
|
locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
Now that all the architectures have implemented support for these new
atomic primitives add on the generic infrastructure to expose and use
it.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-18 01:54:38 +03:00
|
|
|
/* atomic_fetch_sub_relaxed */
|
|
|
|
#ifndef atomic_fetch_sub_relaxed
|
|
|
|
#define atomic_fetch_sub_relaxed atomic_fetch_sub
|
|
|
|
#define atomic_fetch_sub_acquire atomic_fetch_sub
|
|
|
|
#define atomic_fetch_sub_release atomic_fetch_sub
|
|
|
|
|
|
|
|
#else /* atomic_fetch_sub_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_sub_acquire
|
|
|
|
#define atomic_fetch_sub_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic_fetch_sub, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_sub_release
|
|
|
|
#define atomic_fetch_sub_release(...) \
|
|
|
|
__atomic_op_release(atomic_fetch_sub, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_sub
|
|
|
|
#define atomic_fetch_sub(...) \
|
|
|
|
__atomic_op_fence(atomic_fetch_sub, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic_fetch_sub_relaxed */
|
|
|
|
|
2016-06-29 00:56:51 +03:00
|
|
|
/* atomic_fetch_dec_relaxed */
|
|
|
|
#ifndef atomic_fetch_dec_relaxed
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_dec
|
|
|
|
#define atomic_fetch_dec(v) atomic_fetch_sub(1, (v))
|
|
|
|
#define atomic_fetch_dec_relaxed(v) atomic_fetch_sub_relaxed(1, (v))
|
|
|
|
#define atomic_fetch_dec_acquire(v) atomic_fetch_sub_acquire(1, (v))
|
|
|
|
#define atomic_fetch_dec_release(v) atomic_fetch_sub_release(1, (v))
|
|
|
|
#else /* atomic_fetch_dec */
|
|
|
|
#define atomic_fetch_dec_relaxed atomic_fetch_dec
|
|
|
|
#define atomic_fetch_dec_acquire atomic_fetch_dec
|
|
|
|
#define atomic_fetch_dec_release atomic_fetch_dec
|
|
|
|
#endif /* atomic_fetch_dec */
|
|
|
|
|
|
|
|
#else /* atomic_fetch_dec_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_dec_acquire
|
|
|
|
#define atomic_fetch_dec_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic_fetch_dec, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_dec_release
|
|
|
|
#define atomic_fetch_dec_release(...) \
|
|
|
|
__atomic_op_release(atomic_fetch_dec, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_dec
|
|
|
|
#define atomic_fetch_dec(...) \
|
|
|
|
__atomic_op_fence(atomic_fetch_dec, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic_fetch_dec_relaxed */
|
|
|
|
|
locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
Now that all the architectures have implemented support for these new
atomic primitives add on the generic infrastructure to expose and use
it.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-18 01:54:38 +03:00
|
|
|
/* atomic_fetch_or_relaxed */
|
|
|
|
#ifndef atomic_fetch_or_relaxed
|
|
|
|
#define atomic_fetch_or_relaxed atomic_fetch_or
|
|
|
|
#define atomic_fetch_or_acquire atomic_fetch_or
|
|
|
|
#define atomic_fetch_or_release atomic_fetch_or
|
|
|
|
|
|
|
|
#else /* atomic_fetch_or_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_or_acquire
|
|
|
|
#define atomic_fetch_or_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic_fetch_or, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_or_release
|
|
|
|
#define atomic_fetch_or_release(...) \
|
|
|
|
__atomic_op_release(atomic_fetch_or, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_or
|
|
|
|
#define atomic_fetch_or(...) \
|
|
|
|
__atomic_op_fence(atomic_fetch_or, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic_fetch_or_relaxed */
|
|
|
|
|
|
|
|
/* atomic_fetch_and_relaxed */
|
|
|
|
#ifndef atomic_fetch_and_relaxed
|
|
|
|
#define atomic_fetch_and_relaxed atomic_fetch_and
|
|
|
|
#define atomic_fetch_and_acquire atomic_fetch_and
|
|
|
|
#define atomic_fetch_and_release atomic_fetch_and
|
|
|
|
|
|
|
|
#else /* atomic_fetch_and_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_and_acquire
|
|
|
|
#define atomic_fetch_and_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic_fetch_and, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_and_release
|
|
|
|
#define atomic_fetch_and_release(...) \
|
|
|
|
__atomic_op_release(atomic_fetch_and, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_and
|
|
|
|
#define atomic_fetch_and(...) \
|
|
|
|
__atomic_op_fence(atomic_fetch_and, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic_fetch_and_relaxed */
|
|
|
|
|
|
|
|
#ifdef atomic_andnot
|
|
|
|
/* atomic_fetch_andnot_relaxed */
|
|
|
|
#ifndef atomic_fetch_andnot_relaxed
|
|
|
|
#define atomic_fetch_andnot_relaxed atomic_fetch_andnot
|
|
|
|
#define atomic_fetch_andnot_acquire atomic_fetch_andnot
|
|
|
|
#define atomic_fetch_andnot_release atomic_fetch_andnot
|
|
|
|
|
|
|
|
#else /* atomic_fetch_andnot_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_andnot_acquire
|
|
|
|
#define atomic_fetch_andnot_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic_fetch_andnot, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_andnot_release
|
|
|
|
#define atomic_fetch_andnot_release(...) \
|
|
|
|
__atomic_op_release(atomic_fetch_andnot, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_andnot
|
|
|
|
#define atomic_fetch_andnot(...) \
|
|
|
|
__atomic_op_fence(atomic_fetch_andnot, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic_fetch_andnot_relaxed */
|
|
|
|
#endif /* atomic_andnot */
|
|
|
|
|
|
|
|
/* atomic_fetch_xor_relaxed */
|
|
|
|
#ifndef atomic_fetch_xor_relaxed
|
|
|
|
#define atomic_fetch_xor_relaxed atomic_fetch_xor
|
|
|
|
#define atomic_fetch_xor_acquire atomic_fetch_xor
|
|
|
|
#define atomic_fetch_xor_release atomic_fetch_xor
|
|
|
|
|
|
|
|
#else /* atomic_fetch_xor_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_xor_acquire
|
|
|
|
#define atomic_fetch_xor_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic_fetch_xor, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_xor_release
|
|
|
|
#define atomic_fetch_xor_release(...) \
|
|
|
|
__atomic_op_release(atomic_fetch_xor, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_fetch_xor
|
|
|
|
#define atomic_fetch_xor(...) \
|
|
|
|
__atomic_op_fence(atomic_fetch_xor, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic_fetch_xor_relaxed */
|
|
|
|
|
|
|
|
|
locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
Whilst porting the generic qrwlock code over to arm64, it became
apparent that any portable locking code needs finer-grained control of
the memory-ordering guarantees provided by our atomic routines.
In particular: xchg, cmpxchg, {add,sub}_return are often used in
situations where full barrier semantics (currently the only option
available) are not required. For example, when a reader increments a
reader count to obtain a lock, checking the old value to see if a writer
was present, only acquire semantics are strictly needed.
This patch introduces three new ordering semantics for these operations:
- *_relaxed: No ordering guarantees. This is similar to what we have
already for the non-return atomics (e.g. atomic_add).
- *_acquire: ACQUIRE semantics, similar to smp_load_acquire.
- *_release: RELEASE semantics, similar to smp_store_release.
In memory-ordering speak, this means that the acquire/release semantics
are RCpc as opposed to RCsc. Consequently a RELEASE followed by an
ACQUIRE does not imply a full barrier, as already documented in
memory-barriers.txt.
Currently, all the new macros are conditionally mapped to the full-mb
variants, however if the *_relaxed version is provided by the
architecture, then the acquire/release variants are constructed by
supplementing the relaxed routine with an explicit barrier.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman.Long@hp.com
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1438880084-18856-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-06 19:54:37 +03:00
|
|
|
/* atomic_xchg_relaxed */
|
|
|
|
#ifndef atomic_xchg_relaxed
|
|
|
|
#define atomic_xchg_relaxed atomic_xchg
|
|
|
|
#define atomic_xchg_acquire atomic_xchg
|
|
|
|
#define atomic_xchg_release atomic_xchg
|
|
|
|
|
|
|
|
#else /* atomic_xchg_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic_xchg_acquire
|
|
|
|
#define atomic_xchg_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic_xchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_xchg_release
|
|
|
|
#define atomic_xchg_release(...) \
|
|
|
|
__atomic_op_release(atomic_xchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_xchg
|
|
|
|
#define atomic_xchg(...) \
|
|
|
|
__atomic_op_fence(atomic_xchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic_xchg_relaxed */
|
|
|
|
|
|
|
|
/* atomic_cmpxchg_relaxed */
|
|
|
|
#ifndef atomic_cmpxchg_relaxed
|
|
|
|
#define atomic_cmpxchg_relaxed atomic_cmpxchg
|
|
|
|
#define atomic_cmpxchg_acquire atomic_cmpxchg
|
|
|
|
#define atomic_cmpxchg_release atomic_cmpxchg
|
|
|
|
|
|
|
|
#else /* atomic_cmpxchg_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic_cmpxchg_acquire
|
|
|
|
#define atomic_cmpxchg_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic_cmpxchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_cmpxchg_release
|
|
|
|
#define atomic_cmpxchg_release(...) \
|
|
|
|
__atomic_op_release(atomic_cmpxchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_cmpxchg
|
|
|
|
#define atomic_cmpxchg(...) \
|
|
|
|
__atomic_op_fence(atomic_cmpxchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic_cmpxchg_relaxed */
|
|
|
|
|
locking/atomic: Introduce atomic_try_cmpxchg()
Add a new cmpxchg interface:
bool try_cmpxchg(u{8,16,32,64} *ptr, u{8,16,32,64} *val, u{8,16,32,64} new);
Where the boolean returns the result of the compare; and thus if the
exchange happened; and in case of failure, the new value of *ptr is
returned in *val.
This allows simplification/improvement of loops like:
for (;;) {
new = val $op $imm;
old = cmpxchg(ptr, val, new);
if (old == val)
break;
val = old;
}
into:
do {
} while (!try_cmpxchg(ptr, &val, val $op $imm));
while also generating better code (GCC6 and onwards).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-01 18:39:38 +03:00
|
|
|
#ifndef atomic_try_cmpxchg
|
|
|
|
|
|
|
|
#define __atomic_try_cmpxchg(type, _p, _po, _n) \
|
|
|
|
({ \
|
|
|
|
typeof(_po) __po = (_po); \
|
2017-03-27 14:54:38 +03:00
|
|
|
typeof(*(_po)) __r, __o = *__po; \
|
|
|
|
__r = atomic_cmpxchg##type((_p), __o, (_n)); \
|
|
|
|
if (unlikely(__r != __o)) \
|
|
|
|
*__po = __r; \
|
|
|
|
likely(__r == __o); \
|
locking/atomic: Introduce atomic_try_cmpxchg()
Add a new cmpxchg interface:
bool try_cmpxchg(u{8,16,32,64} *ptr, u{8,16,32,64} *val, u{8,16,32,64} new);
Where the boolean returns the result of the compare; and thus if the
exchange happened; and in case of failure, the new value of *ptr is
returned in *val.
This allows simplification/improvement of loops like:
for (;;) {
new = val $op $imm;
old = cmpxchg(ptr, val, new);
if (old == val)
break;
val = old;
}
into:
do {
} while (!try_cmpxchg(ptr, &val, val $op $imm));
while also generating better code (GCC6 and onwards).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-01 18:39:38 +03:00
|
|
|
})
|
|
|
|
|
|
|
|
#define atomic_try_cmpxchg(_p, _po, _n) __atomic_try_cmpxchg(, _p, _po, _n)
|
|
|
|
#define atomic_try_cmpxchg_relaxed(_p, _po, _n) __atomic_try_cmpxchg(_relaxed, _p, _po, _n)
|
|
|
|
#define atomic_try_cmpxchg_acquire(_p, _po, _n) __atomic_try_cmpxchg(_acquire, _p, _po, _n)
|
|
|
|
#define atomic_try_cmpxchg_release(_p, _po, _n) __atomic_try_cmpxchg(_release, _p, _po, _n)
|
|
|
|
|
|
|
|
#else /* atomic_try_cmpxchg */
|
|
|
|
#define atomic_try_cmpxchg_relaxed atomic_try_cmpxchg
|
|
|
|
#define atomic_try_cmpxchg_acquire atomic_try_cmpxchg
|
|
|
|
#define atomic_try_cmpxchg_release atomic_try_cmpxchg
|
|
|
|
#endif /* atomic_try_cmpxchg */
|
|
|
|
|
locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
Whilst porting the generic qrwlock code over to arm64, it became
apparent that any portable locking code needs finer-grained control of
the memory-ordering guarantees provided by our atomic routines.
In particular: xchg, cmpxchg, {add,sub}_return are often used in
situations where full barrier semantics (currently the only option
available) are not required. For example, when a reader increments a
reader count to obtain a lock, checking the old value to see if a writer
was present, only acquire semantics are strictly needed.
This patch introduces three new ordering semantics for these operations:
- *_relaxed: No ordering guarantees. This is similar to what we have
already for the non-return atomics (e.g. atomic_add).
- *_acquire: ACQUIRE semantics, similar to smp_load_acquire.
- *_release: RELEASE semantics, similar to smp_store_release.
In memory-ordering speak, this means that the acquire/release semantics
are RCpc as opposed to RCsc. Consequently a RELEASE followed by an
ACQUIRE does not imply a full barrier, as already documented in
memory-barriers.txt.
Currently, all the new macros are conditionally mapped to the full-mb
variants, however if the *_relaxed version is provided by the
architecture, then the acquire/release variants are constructed by
supplementing the relaxed routine with an explicit barrier.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman.Long@hp.com
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1438880084-18856-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-06 19:54:37 +03:00
|
|
|
/* cmpxchg_relaxed */
|
|
|
|
#ifndef cmpxchg_relaxed
|
|
|
|
#define cmpxchg_relaxed cmpxchg
|
|
|
|
#define cmpxchg_acquire cmpxchg
|
|
|
|
#define cmpxchg_release cmpxchg
|
|
|
|
|
|
|
|
#else /* cmpxchg_relaxed */
|
|
|
|
|
|
|
|
#ifndef cmpxchg_acquire
|
|
|
|
#define cmpxchg_acquire(...) \
|
|
|
|
__atomic_op_acquire(cmpxchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef cmpxchg_release
|
|
|
|
#define cmpxchg_release(...) \
|
|
|
|
__atomic_op_release(cmpxchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef cmpxchg
|
|
|
|
#define cmpxchg(...) \
|
|
|
|
__atomic_op_fence(cmpxchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* cmpxchg_relaxed */
|
|
|
|
|
|
|
|
/* cmpxchg64_relaxed */
|
|
|
|
#ifndef cmpxchg64_relaxed
|
|
|
|
#define cmpxchg64_relaxed cmpxchg64
|
|
|
|
#define cmpxchg64_acquire cmpxchg64
|
|
|
|
#define cmpxchg64_release cmpxchg64
|
|
|
|
|
|
|
|
#else /* cmpxchg64_relaxed */
|
|
|
|
|
|
|
|
#ifndef cmpxchg64_acquire
|
|
|
|
#define cmpxchg64_acquire(...) \
|
|
|
|
__atomic_op_acquire(cmpxchg64, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef cmpxchg64_release
|
|
|
|
#define cmpxchg64_release(...) \
|
|
|
|
__atomic_op_release(cmpxchg64, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef cmpxchg64
|
|
|
|
#define cmpxchg64(...) \
|
|
|
|
__atomic_op_fence(cmpxchg64, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* cmpxchg64_relaxed */
|
|
|
|
|
|
|
|
/* xchg_relaxed */
|
|
|
|
#ifndef xchg_relaxed
|
|
|
|
#define xchg_relaxed xchg
|
|
|
|
#define xchg_acquire xchg
|
|
|
|
#define xchg_release xchg
|
|
|
|
|
|
|
|
#else /* xchg_relaxed */
|
|
|
|
|
|
|
|
#ifndef xchg_acquire
|
|
|
|
#define xchg_acquire(...) __atomic_op_acquire(xchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef xchg_release
|
|
|
|
#define xchg_release(...) __atomic_op_release(xchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef xchg
|
|
|
|
#define xchg(...) __atomic_op_fence(xchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* xchg_relaxed */
|
2010-11-12 01:05:08 +03:00
|
|
|
|
2011-07-27 03:09:07 +04:00
|
|
|
/**
|
|
|
|
* atomic_add_unless - add unless the number is already a given value
|
|
|
|
* @v: pointer of type atomic_t
|
|
|
|
* @a: the amount to add to v...
|
|
|
|
* @u: ...unless v is equal to u.
|
|
|
|
*
|
|
|
|
* Atomically adds @a to @v, so long as @v was not already @u.
|
|
|
|
* Returns non-zero if @v was not @u, and zero otherwise.
|
|
|
|
*/
|
|
|
|
static inline int atomic_add_unless(atomic_t *v, int a, int u)
|
|
|
|
{
|
|
|
|
return __atomic_add_unless(v, a, u) != u;
|
|
|
|
}
|
|
|
|
|
2011-07-27 03:09:06 +04:00
|
|
|
/**
|
|
|
|
* atomic_inc_not_zero - increment unless the number is zero
|
|
|
|
* @v: pointer of type atomic_t
|
|
|
|
*
|
|
|
|
* Atomically increments @v by 1, so long as @v is non-zero.
|
|
|
|
* Returns non-zero if @v was non-zero, and zero otherwise.
|
|
|
|
*/
|
2012-03-01 01:09:53 +04:00
|
|
|
#ifndef atomic_inc_not_zero
|
2011-07-27 03:09:06 +04:00
|
|
|
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
|
2012-03-01 01:09:53 +04:00
|
|
|
#endif
|
2011-07-27 03:09:06 +04:00
|
|
|
|
2015-04-24 02:12:32 +03:00
|
|
|
#ifndef atomic_andnot
|
|
|
|
static inline void atomic_andnot(int i, atomic_t *v)
|
|
|
|
{
|
|
|
|
atomic_and(~i, v);
|
|
|
|
}
|
locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
Now that all the architectures have implemented support for these new
atomic primitives add on the generic infrastructure to expose and use
it.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-18 01:54:38 +03:00
|
|
|
|
|
|
|
static inline int atomic_fetch_andnot(int i, atomic_t *v)
|
|
|
|
{
|
|
|
|
return atomic_fetch_and(~i, v);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int atomic_fetch_andnot_relaxed(int i, atomic_t *v)
|
|
|
|
{
|
|
|
|
return atomic_fetch_and_relaxed(~i, v);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int atomic_fetch_andnot_acquire(int i, atomic_t *v)
|
|
|
|
{
|
|
|
|
return atomic_fetch_and_acquire(~i, v);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int atomic_fetch_andnot_release(int i, atomic_t *v)
|
|
|
|
{
|
|
|
|
return atomic_fetch_and_release(~i, v);
|
|
|
|
}
|
2015-04-24 02:12:32 +03:00
|
|
|
#endif
|
|
|
|
|
2010-11-12 01:05:08 +03:00
|
|
|
/**
|
|
|
|
* atomic_inc_not_zero_hint - increment if not null
|
|
|
|
* @v: pointer of type atomic_t
|
|
|
|
* @hint: probable value of the atomic before the increment
|
|
|
|
*
|
|
|
|
* This version of atomic_inc_not_zero() gives a hint of probable
|
|
|
|
* value of the atomic. This helps processor to not read the memory
|
|
|
|
* before doing the atomic read/modify/write cycle, lowering
|
|
|
|
* number of bus transactions on some arches.
|
|
|
|
*
|
|
|
|
* Returns: 0 if increment was not done, 1 otherwise.
|
|
|
|
*/
|
|
|
|
#ifndef atomic_inc_not_zero_hint
|
|
|
|
static inline int atomic_inc_not_zero_hint(atomic_t *v, int hint)
|
|
|
|
{
|
|
|
|
int val, c = hint;
|
|
|
|
|
|
|
|
/* sanity test, should be removed by compiler if hint is a constant */
|
|
|
|
if (!hint)
|
|
|
|
return atomic_inc_not_zero(v);
|
|
|
|
|
|
|
|
do {
|
|
|
|
val = atomic_cmpxchg(v, c, c + 1);
|
|
|
|
if (val == c)
|
|
|
|
return 1;
|
|
|
|
c = val;
|
|
|
|
} while (c);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
2011-06-20 18:52:57 +04:00
|
|
|
#ifndef atomic_inc_unless_negative
|
|
|
|
static inline int atomic_inc_unless_negative(atomic_t *p)
|
|
|
|
{
|
|
|
|
int v, v1;
|
|
|
|
for (v = 0; v >= 0; v = v1) {
|
|
|
|
v1 = atomic_cmpxchg(p, v, v + 1);
|
|
|
|
if (likely(v1 == v))
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic_dec_unless_positive
|
|
|
|
static inline int atomic_dec_unless_positive(atomic_t *p)
|
|
|
|
{
|
|
|
|
int v, v1;
|
|
|
|
for (v = 0; v <= 0; v = v1) {
|
|
|
|
v1 = atomic_cmpxchg(p, v, v - 1);
|
|
|
|
if (likely(v1 == v))
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
2012-10-09 03:32:18 +04:00
|
|
|
/*
|
|
|
|
* atomic_dec_if_positive - decrement by 1 if old value positive
|
|
|
|
* @v: pointer of type atomic_t
|
|
|
|
*
|
|
|
|
* The function returns the old value of *v minus 1, even if
|
|
|
|
* the atomic variable, v, was not decremented.
|
|
|
|
*/
|
|
|
|
#ifndef atomic_dec_if_positive
|
|
|
|
static inline int atomic_dec_if_positive(atomic_t *v)
|
|
|
|
{
|
|
|
|
int c, old, dec;
|
|
|
|
c = atomic_read(v);
|
|
|
|
for (;;) {
|
|
|
|
dec = c - 1;
|
|
|
|
if (unlikely(dec < 0))
|
|
|
|
break;
|
|
|
|
old = atomic_cmpxchg((v), c, dec);
|
|
|
|
if (likely(old == c))
|
|
|
|
break;
|
|
|
|
c = old;
|
|
|
|
}
|
|
|
|
return dec;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
2011-07-27 03:09:08 +04:00
|
|
|
#ifdef CONFIG_GENERIC_ATOMIC64
|
|
|
|
#include <asm-generic/atomic64.h>
|
|
|
|
#endif
|
2015-04-24 02:12:32 +03:00
|
|
|
|
2016-04-18 01:52:13 +03:00
|
|
|
#ifndef atomic64_read_acquire
|
|
|
|
#define atomic64_read_acquire(v) smp_load_acquire(&(v)->counter)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_set_release
|
|
|
|
#define atomic64_set_release(v, i) smp_store_release(&(v)->counter, (i))
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/* atomic64_add_return_relaxed */
|
|
|
|
#ifndef atomic64_add_return_relaxed
|
|
|
|
#define atomic64_add_return_relaxed atomic64_add_return
|
|
|
|
#define atomic64_add_return_acquire atomic64_add_return
|
|
|
|
#define atomic64_add_return_release atomic64_add_return
|
|
|
|
|
|
|
|
#else /* atomic64_add_return_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic64_add_return_acquire
|
|
|
|
#define atomic64_add_return_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic64_add_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_add_return_release
|
|
|
|
#define atomic64_add_return_release(...) \
|
|
|
|
__atomic_op_release(atomic64_add_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_add_return
|
|
|
|
#define atomic64_add_return(...) \
|
|
|
|
__atomic_op_fence(atomic64_add_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic64_add_return_relaxed */
|
|
|
|
|
|
|
|
/* atomic64_inc_return_relaxed */
|
|
|
|
#ifndef atomic64_inc_return_relaxed
|
|
|
|
#define atomic64_inc_return_relaxed atomic64_inc_return
|
|
|
|
#define atomic64_inc_return_acquire atomic64_inc_return
|
|
|
|
#define atomic64_inc_return_release atomic64_inc_return
|
|
|
|
|
|
|
|
#else /* atomic64_inc_return_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic64_inc_return_acquire
|
|
|
|
#define atomic64_inc_return_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic64_inc_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_inc_return_release
|
|
|
|
#define atomic64_inc_return_release(...) \
|
|
|
|
__atomic_op_release(atomic64_inc_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_inc_return
|
|
|
|
#define atomic64_inc_return(...) \
|
|
|
|
__atomic_op_fence(atomic64_inc_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic64_inc_return_relaxed */
|
|
|
|
|
|
|
|
|
|
|
|
/* atomic64_sub_return_relaxed */
|
|
|
|
#ifndef atomic64_sub_return_relaxed
|
|
|
|
#define atomic64_sub_return_relaxed atomic64_sub_return
|
|
|
|
#define atomic64_sub_return_acquire atomic64_sub_return
|
|
|
|
#define atomic64_sub_return_release atomic64_sub_return
|
|
|
|
|
|
|
|
#else /* atomic64_sub_return_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic64_sub_return_acquire
|
|
|
|
#define atomic64_sub_return_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic64_sub_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_sub_return_release
|
|
|
|
#define atomic64_sub_return_release(...) \
|
|
|
|
__atomic_op_release(atomic64_sub_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_sub_return
|
|
|
|
#define atomic64_sub_return(...) \
|
|
|
|
__atomic_op_fence(atomic64_sub_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic64_sub_return_relaxed */
|
|
|
|
|
|
|
|
/* atomic64_dec_return_relaxed */
|
|
|
|
#ifndef atomic64_dec_return_relaxed
|
|
|
|
#define atomic64_dec_return_relaxed atomic64_dec_return
|
|
|
|
#define atomic64_dec_return_acquire atomic64_dec_return
|
|
|
|
#define atomic64_dec_return_release atomic64_dec_return
|
|
|
|
|
|
|
|
#else /* atomic64_dec_return_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic64_dec_return_acquire
|
|
|
|
#define atomic64_dec_return_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic64_dec_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_dec_return_release
|
|
|
|
#define atomic64_dec_return_release(...) \
|
|
|
|
__atomic_op_release(atomic64_dec_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_dec_return
|
|
|
|
#define atomic64_dec_return(...) \
|
|
|
|
__atomic_op_fence(atomic64_dec_return, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic64_dec_return_relaxed */
|
|
|
|
|
locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
Now that all the architectures have implemented support for these new
atomic primitives add on the generic infrastructure to expose and use
it.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-18 01:54:38 +03:00
|
|
|
|
|
|
|
/* atomic64_fetch_add_relaxed */
|
|
|
|
#ifndef atomic64_fetch_add_relaxed
|
|
|
|
#define atomic64_fetch_add_relaxed atomic64_fetch_add
|
|
|
|
#define atomic64_fetch_add_acquire atomic64_fetch_add
|
|
|
|
#define atomic64_fetch_add_release atomic64_fetch_add
|
|
|
|
|
|
|
|
#else /* atomic64_fetch_add_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_add_acquire
|
|
|
|
#define atomic64_fetch_add_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic64_fetch_add, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_add_release
|
|
|
|
#define atomic64_fetch_add_release(...) \
|
|
|
|
__atomic_op_release(atomic64_fetch_add, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_add
|
|
|
|
#define atomic64_fetch_add(...) \
|
|
|
|
__atomic_op_fence(atomic64_fetch_add, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic64_fetch_add_relaxed */
|
|
|
|
|
2016-06-29 00:56:51 +03:00
|
|
|
/* atomic64_fetch_inc_relaxed */
|
|
|
|
#ifndef atomic64_fetch_inc_relaxed
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_inc
|
|
|
|
#define atomic64_fetch_inc(v) atomic64_fetch_add(1, (v))
|
|
|
|
#define atomic64_fetch_inc_relaxed(v) atomic64_fetch_add_relaxed(1, (v))
|
|
|
|
#define atomic64_fetch_inc_acquire(v) atomic64_fetch_add_acquire(1, (v))
|
|
|
|
#define atomic64_fetch_inc_release(v) atomic64_fetch_add_release(1, (v))
|
|
|
|
#else /* atomic64_fetch_inc */
|
|
|
|
#define atomic64_fetch_inc_relaxed atomic64_fetch_inc
|
|
|
|
#define atomic64_fetch_inc_acquire atomic64_fetch_inc
|
|
|
|
#define atomic64_fetch_inc_release atomic64_fetch_inc
|
|
|
|
#endif /* atomic64_fetch_inc */
|
|
|
|
|
|
|
|
#else /* atomic64_fetch_inc_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_inc_acquire
|
|
|
|
#define atomic64_fetch_inc_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic64_fetch_inc, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_inc_release
|
|
|
|
#define atomic64_fetch_inc_release(...) \
|
|
|
|
__atomic_op_release(atomic64_fetch_inc, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_inc
|
|
|
|
#define atomic64_fetch_inc(...) \
|
|
|
|
__atomic_op_fence(atomic64_fetch_inc, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic64_fetch_inc_relaxed */
|
|
|
|
|
locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
Now that all the architectures have implemented support for these new
atomic primitives add on the generic infrastructure to expose and use
it.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-18 01:54:38 +03:00
|
|
|
/* atomic64_fetch_sub_relaxed */
|
|
|
|
#ifndef atomic64_fetch_sub_relaxed
|
|
|
|
#define atomic64_fetch_sub_relaxed atomic64_fetch_sub
|
|
|
|
#define atomic64_fetch_sub_acquire atomic64_fetch_sub
|
|
|
|
#define atomic64_fetch_sub_release atomic64_fetch_sub
|
|
|
|
|
|
|
|
#else /* atomic64_fetch_sub_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_sub_acquire
|
|
|
|
#define atomic64_fetch_sub_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic64_fetch_sub, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_sub_release
|
|
|
|
#define atomic64_fetch_sub_release(...) \
|
|
|
|
__atomic_op_release(atomic64_fetch_sub, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_sub
|
|
|
|
#define atomic64_fetch_sub(...) \
|
|
|
|
__atomic_op_fence(atomic64_fetch_sub, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic64_fetch_sub_relaxed */
|
|
|
|
|
2016-06-29 00:56:51 +03:00
|
|
|
/* atomic64_fetch_dec_relaxed */
|
|
|
|
#ifndef atomic64_fetch_dec_relaxed
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_dec
|
|
|
|
#define atomic64_fetch_dec(v) atomic64_fetch_sub(1, (v))
|
|
|
|
#define atomic64_fetch_dec_relaxed(v) atomic64_fetch_sub_relaxed(1, (v))
|
|
|
|
#define atomic64_fetch_dec_acquire(v) atomic64_fetch_sub_acquire(1, (v))
|
|
|
|
#define atomic64_fetch_dec_release(v) atomic64_fetch_sub_release(1, (v))
|
|
|
|
#else /* atomic64_fetch_dec */
|
|
|
|
#define atomic64_fetch_dec_relaxed atomic64_fetch_dec
|
|
|
|
#define atomic64_fetch_dec_acquire atomic64_fetch_dec
|
|
|
|
#define atomic64_fetch_dec_release atomic64_fetch_dec
|
|
|
|
#endif /* atomic64_fetch_dec */
|
|
|
|
|
|
|
|
#else /* atomic64_fetch_dec_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_dec_acquire
|
|
|
|
#define atomic64_fetch_dec_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic64_fetch_dec, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_dec_release
|
|
|
|
#define atomic64_fetch_dec_release(...) \
|
|
|
|
__atomic_op_release(atomic64_fetch_dec, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_dec
|
|
|
|
#define atomic64_fetch_dec(...) \
|
|
|
|
__atomic_op_fence(atomic64_fetch_dec, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic64_fetch_dec_relaxed */
|
|
|
|
|
locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
Now that all the architectures have implemented support for these new
atomic primitives add on the generic infrastructure to expose and use
it.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-18 01:54:38 +03:00
|
|
|
/* atomic64_fetch_or_relaxed */
|
|
|
|
#ifndef atomic64_fetch_or_relaxed
|
|
|
|
#define atomic64_fetch_or_relaxed atomic64_fetch_or
|
|
|
|
#define atomic64_fetch_or_acquire atomic64_fetch_or
|
|
|
|
#define atomic64_fetch_or_release atomic64_fetch_or
|
|
|
|
|
|
|
|
#else /* atomic64_fetch_or_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_or_acquire
|
|
|
|
#define atomic64_fetch_or_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic64_fetch_or, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_or_release
|
|
|
|
#define atomic64_fetch_or_release(...) \
|
|
|
|
__atomic_op_release(atomic64_fetch_or, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_or
|
|
|
|
#define atomic64_fetch_or(...) \
|
|
|
|
__atomic_op_fence(atomic64_fetch_or, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic64_fetch_or_relaxed */
|
|
|
|
|
|
|
|
/* atomic64_fetch_and_relaxed */
|
|
|
|
#ifndef atomic64_fetch_and_relaxed
|
|
|
|
#define atomic64_fetch_and_relaxed atomic64_fetch_and
|
|
|
|
#define atomic64_fetch_and_acquire atomic64_fetch_and
|
|
|
|
#define atomic64_fetch_and_release atomic64_fetch_and
|
|
|
|
|
|
|
|
#else /* atomic64_fetch_and_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_and_acquire
|
|
|
|
#define atomic64_fetch_and_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic64_fetch_and, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_and_release
|
|
|
|
#define atomic64_fetch_and_release(...) \
|
|
|
|
__atomic_op_release(atomic64_fetch_and, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_and
|
|
|
|
#define atomic64_fetch_and(...) \
|
|
|
|
__atomic_op_fence(atomic64_fetch_and, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic64_fetch_and_relaxed */
|
|
|
|
|
|
|
|
#ifdef atomic64_andnot
|
|
|
|
/* atomic64_fetch_andnot_relaxed */
|
|
|
|
#ifndef atomic64_fetch_andnot_relaxed
|
|
|
|
#define atomic64_fetch_andnot_relaxed atomic64_fetch_andnot
|
|
|
|
#define atomic64_fetch_andnot_acquire atomic64_fetch_andnot
|
|
|
|
#define atomic64_fetch_andnot_release atomic64_fetch_andnot
|
|
|
|
|
|
|
|
#else /* atomic64_fetch_andnot_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_andnot_acquire
|
|
|
|
#define atomic64_fetch_andnot_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic64_fetch_andnot, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_andnot_release
|
|
|
|
#define atomic64_fetch_andnot_release(...) \
|
|
|
|
__atomic_op_release(atomic64_fetch_andnot, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_andnot
|
|
|
|
#define atomic64_fetch_andnot(...) \
|
|
|
|
__atomic_op_fence(atomic64_fetch_andnot, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic64_fetch_andnot_relaxed */
|
|
|
|
#endif /* atomic64_andnot */
|
|
|
|
|
|
|
|
/* atomic64_fetch_xor_relaxed */
|
|
|
|
#ifndef atomic64_fetch_xor_relaxed
|
|
|
|
#define atomic64_fetch_xor_relaxed atomic64_fetch_xor
|
|
|
|
#define atomic64_fetch_xor_acquire atomic64_fetch_xor
|
|
|
|
#define atomic64_fetch_xor_release atomic64_fetch_xor
|
|
|
|
|
|
|
|
#else /* atomic64_fetch_xor_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_xor_acquire
|
|
|
|
#define atomic64_fetch_xor_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic64_fetch_xor, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_xor_release
|
|
|
|
#define atomic64_fetch_xor_release(...) \
|
|
|
|
__atomic_op_release(atomic64_fetch_xor, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_fetch_xor
|
|
|
|
#define atomic64_fetch_xor(...) \
|
|
|
|
__atomic_op_fence(atomic64_fetch_xor, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic64_fetch_xor_relaxed */
|
|
|
|
|
|
|
|
|
2016-04-18 01:52:13 +03:00
|
|
|
/* atomic64_xchg_relaxed */
|
|
|
|
#ifndef atomic64_xchg_relaxed
|
|
|
|
#define atomic64_xchg_relaxed atomic64_xchg
|
|
|
|
#define atomic64_xchg_acquire atomic64_xchg
|
|
|
|
#define atomic64_xchg_release atomic64_xchg
|
|
|
|
|
|
|
|
#else /* atomic64_xchg_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic64_xchg_acquire
|
|
|
|
#define atomic64_xchg_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic64_xchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_xchg_release
|
|
|
|
#define atomic64_xchg_release(...) \
|
|
|
|
__atomic_op_release(atomic64_xchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_xchg
|
|
|
|
#define atomic64_xchg(...) \
|
|
|
|
__atomic_op_fence(atomic64_xchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic64_xchg_relaxed */
|
|
|
|
|
|
|
|
/* atomic64_cmpxchg_relaxed */
|
|
|
|
#ifndef atomic64_cmpxchg_relaxed
|
|
|
|
#define atomic64_cmpxchg_relaxed atomic64_cmpxchg
|
|
|
|
#define atomic64_cmpxchg_acquire atomic64_cmpxchg
|
|
|
|
#define atomic64_cmpxchg_release atomic64_cmpxchg
|
|
|
|
|
|
|
|
#else /* atomic64_cmpxchg_relaxed */
|
|
|
|
|
|
|
|
#ifndef atomic64_cmpxchg_acquire
|
|
|
|
#define atomic64_cmpxchg_acquire(...) \
|
|
|
|
__atomic_op_acquire(atomic64_cmpxchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_cmpxchg_release
|
|
|
|
#define atomic64_cmpxchg_release(...) \
|
|
|
|
__atomic_op_release(atomic64_cmpxchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifndef atomic64_cmpxchg
|
|
|
|
#define atomic64_cmpxchg(...) \
|
|
|
|
__atomic_op_fence(atomic64_cmpxchg, __VA_ARGS__)
|
|
|
|
#endif
|
|
|
|
#endif /* atomic64_cmpxchg_relaxed */
|
|
|
|
|
locking/atomic: Introduce atomic_try_cmpxchg()
Add a new cmpxchg interface:
bool try_cmpxchg(u{8,16,32,64} *ptr, u{8,16,32,64} *val, u{8,16,32,64} new);
Where the boolean returns the result of the compare; and thus if the
exchange happened; and in case of failure, the new value of *ptr is
returned in *val.
This allows simplification/improvement of loops like:
for (;;) {
new = val $op $imm;
old = cmpxchg(ptr, val, new);
if (old == val)
break;
val = old;
}
into:
do {
} while (!try_cmpxchg(ptr, &val, val $op $imm));
while also generating better code (GCC6 and onwards).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-01 18:39:38 +03:00
|
|
|
#ifndef atomic64_try_cmpxchg
|
|
|
|
|
|
|
|
#define __atomic64_try_cmpxchg(type, _p, _po, _n) \
|
|
|
|
({ \
|
|
|
|
typeof(_po) __po = (_po); \
|
2017-03-27 14:54:38 +03:00
|
|
|
typeof(*(_po)) __r, __o = *__po; \
|
|
|
|
__r = atomic64_cmpxchg##type((_p), __o, (_n)); \
|
|
|
|
if (unlikely(__r != __o)) \
|
|
|
|
*__po = __r; \
|
|
|
|
likely(__r == __o); \
|
locking/atomic: Introduce atomic_try_cmpxchg()
Add a new cmpxchg interface:
bool try_cmpxchg(u{8,16,32,64} *ptr, u{8,16,32,64} *val, u{8,16,32,64} new);
Where the boolean returns the result of the compare; and thus if the
exchange happened; and in case of failure, the new value of *ptr is
returned in *val.
This allows simplification/improvement of loops like:
for (;;) {
new = val $op $imm;
old = cmpxchg(ptr, val, new);
if (old == val)
break;
val = old;
}
into:
do {
} while (!try_cmpxchg(ptr, &val, val $op $imm));
while also generating better code (GCC6 and onwards).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-01 18:39:38 +03:00
|
|
|
})
|
|
|
|
|
|
|
|
#define atomic64_try_cmpxchg(_p, _po, _n) __atomic64_try_cmpxchg(, _p, _po, _n)
|
|
|
|
#define atomic64_try_cmpxchg_relaxed(_p, _po, _n) __atomic64_try_cmpxchg(_relaxed, _p, _po, _n)
|
|
|
|
#define atomic64_try_cmpxchg_acquire(_p, _po, _n) __atomic64_try_cmpxchg(_acquire, _p, _po, _n)
|
|
|
|
#define atomic64_try_cmpxchg_release(_p, _po, _n) __atomic64_try_cmpxchg(_release, _p, _po, _n)
|
|
|
|
|
|
|
|
#else /* atomic64_try_cmpxchg */
|
|
|
|
#define atomic64_try_cmpxchg_relaxed atomic64_try_cmpxchg
|
|
|
|
#define atomic64_try_cmpxchg_acquire atomic64_try_cmpxchg
|
|
|
|
#define atomic64_try_cmpxchg_release atomic64_try_cmpxchg
|
|
|
|
#endif /* atomic64_try_cmpxchg */
|
|
|
|
|
2015-04-24 02:12:32 +03:00
|
|
|
#ifndef atomic64_andnot
|
|
|
|
static inline void atomic64_andnot(long long i, atomic64_t *v)
|
|
|
|
{
|
|
|
|
atomic64_and(~i, v);
|
|
|
|
}
|
locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
Now that all the architectures have implemented support for these new
atomic primitives add on the generic infrastructure to expose and use
it.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-18 01:54:38 +03:00
|
|
|
|
|
|
|
static inline long long atomic64_fetch_andnot(long long i, atomic64_t *v)
|
|
|
|
{
|
|
|
|
return atomic64_fetch_and(~i, v);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline long long atomic64_fetch_andnot_relaxed(long long i, atomic64_t *v)
|
|
|
|
{
|
|
|
|
return atomic64_fetch_and_relaxed(~i, v);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline long long atomic64_fetch_andnot_acquire(long long i, atomic64_t *v)
|
|
|
|
{
|
|
|
|
return atomic64_fetch_and_acquire(~i, v);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline long long atomic64_fetch_andnot_release(long long i, atomic64_t *v)
|
|
|
|
{
|
|
|
|
return atomic64_fetch_and_release(~i, v);
|
|
|
|
}
|
2015-04-24 02:12:32 +03:00
|
|
|
#endif
|
|
|
|
|
2015-09-18 16:04:59 +03:00
|
|
|
#include <asm-generic/atomic-long.h>
|
|
|
|
|
2010-11-12 01:05:08 +03:00
|
|
|
#endif /* _LINUX_ATOMIC_H */
|