kernel/linux.git/arch/s390/include/asm/atomic.h, branch linux-7.0.y

s390/atomic: Provide arch_atomic_*_and_test() implementations

2024-12-15T15:19:03+00:00

Provide arch_atomic_*_and_test() implementations which make use of flag output constraints, and allow the compiler to generate slightly better code. Reviewed-by: Juergen Christ Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev

s390/atomic: Consistent layering between atomic.h and atomic_ops.h

2024-12-15T14:13:43+00:00

With commit c8a91c285d8c ("s390/atomic: move remaining inline assemblies to atomic_ops.h") all remaining atomic inline assemblies have been moved to atomic_ops.h. However the result is inconsistent: the functions in atomic_ops.h are supposed to be used with integral types like int and long pointers, while the functions in atomic.h work with atomic types. This layering got violated with the named commit. Therefore adjust this now, and also use consistent variable names in atomic_ops.h. Reviewed-by: Alexander Gordeev Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev

s390/atomic: Implement arch_atomic_inc() / arch_atomic_dec()

2024-12-15T14:13:42+00:00

Implement arch_atomic_inc() / arch_atomic_dec() functions which result in a single instruction if compiled for z196 or newer architectures. Reduces the kernel image size by ~6K (defconfig): bloat-o-meter: add/remove: 0/0 grow/shrink: 12/1005 up/down: 106/-6404 (-6298) Reviewed-by: Alexander Gordeev Signed-off-by: Heiko Carstens Signed-off-by: Alexander Gordeev

s390/atomic: Provide arch_atomic_try_cmpxchg()

2024-11-12T13:01:29+00:00

Since gcc 14 flag output operands are supported also for s390. Provide an arch_atomic try_cmpxchg() implementation so that all existing atomic_try_cmpxchg() usages generate slightly better code, if compiled with gcc 14 or newer. Reviewed-by: Juergen Christ Signed-off-by: Heiko Carstens

s390/cmpxchg: Use arch_cmpxchg() instead of __atomic_cmpxchg()

2024-11-12T13:01:28+00:00

Use arch_cmpxchg() instead of __atomic_cmpxchg() for the arch_atomic_cmpxchg() implementations. arch_cmpxchg() generates the same code and doesn't need a cast like it is required for arch_atomic64_cmpxchg(). Reviewed-by: Juergen Christ Signed-off-by: Heiko Carstens

s390/atomic: Convert arch_atomic_xchg() to C function

2024-11-12T13:01:28+00:00

Convert the arch_atomic_xchg define to a C function so that proper type checking is provided. Reviewed-by: Juergen Christ Signed-off-by: Heiko Carstens

s390/atomic: mark all functions __always_inline

2024-04-03T13:00:19+00:00

Atomic functions are quite ubiquitous and may be called by noinstr ones, introducing unwanted instrumentation. They are very small, so there are no significant downsides to force-inlining them. Signed-off-by: Ilya Leoshkevich Link: https://lore.kernel.org/r/20240320230007.4782-2-iii@linux.ibm.com Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik

locking/atomic: make ARCH_ATOMIC a Kconfig symbol

2021-05-26T11:20:49+00:00

Subsequent patches will move architectures over to the ARCH_ATOMIC API, after preparing the asm-generic atomic implementations to function with or without ARCH_ATOMIC. As some architectures use the asm-generic implementations exclusively (and don't have a local atomic.h), and to avoid the risk that ARCH_ATOMIC isn't defined in some cases we expect, let's make the ARCH_ATOMIC macro a Kconfig symbol instead, so that we can guarantee it is consistently available where needed. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland Cc: Boqun Feng Cc: Peter Zijlstra Cc: Will Deacon Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20210525140232.53872-2-mark.rutland@arm.com

s390/atomic,cmpxchg: switch to use atomic-instrumented.h

2021-04-12T10:46:43+00:00

Add arch_ prefix to all atomic operations, and define ARCH_ATOMIC. This enables KASAN instrumentation for all atomic operations on s390. This is the s390 variant of commit 8bf705d13039 ("locking/atomic/x86: Switch atomic.h to use atomic-instrumented.h"). Signed-off-by: Heiko Carstens

s390/atomic: move remaining inline assemblies to atomic_ops.h

2021-04-12T10:46:42+00:00

Move all remaining inline assemblies from atomic.h to atomic_ops.h. That way all atomic inline assemblies are contained within only a single header file. Signed-off-by: Heiko Carstens