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![]() Currently each ordering variant has several potential definitions, with a mixture of preprocessor and C definitions, including several copies of its C prototype, e.g. | #if defined(arch_atomic_fetch_andnot_acquire) | #define raw_atomic_fetch_andnot_acquire arch_atomic_fetch_andnot_acquire | #elif defined(arch_atomic_fetch_andnot_relaxed) | static __always_inline int | raw_atomic_fetch_andnot_acquire(int i, atomic_t *v) | { | int ret = arch_atomic_fetch_andnot_relaxed(i, v); | __atomic_acquire_fence(); | return ret; | } | #elif defined(arch_atomic_fetch_andnot) | #define raw_atomic_fetch_andnot_acquire arch_atomic_fetch_andnot | #else | static __always_inline int | raw_atomic_fetch_andnot_acquire(int i, atomic_t *v) | { | return raw_atomic_fetch_and_acquire(~i, v); | } | #endif Make this a bit simpler by defining the C prototype once, and writing the various potential definitions as plain C code guarded by ifdeffery. For example, the above becomes: | static __always_inline int | raw_atomic_fetch_andnot_acquire(int i, atomic_t *v) | { | #if defined(arch_atomic_fetch_andnot_acquire) | return arch_atomic_fetch_andnot_acquire(i, v); | #elif defined(arch_atomic_fetch_andnot_relaxed) | int ret = arch_atomic_fetch_andnot_relaxed(i, v); | __atomic_acquire_fence(); | return ret; | #elif defined(arch_atomic_fetch_andnot) | return arch_atomic_fetch_andnot(i, v); | #else | return raw_atomic_fetch_and_acquire(~i, v); | #endif | } Which is far easier to read. As we now always have a single copy of the C prototype wrapping all the potential definitions, we now have an obvious single location for kerneldoc comments. At the same time, the fallbacks for raw_atomic*_xhcg() are made to use 'new' rather than 'i' as the name of the new value. This is what the existing fallback template used, and is more consistent with the raw_atomic{_try,}cmpxchg() fallbacks. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20230605070124.3741859-24-mark.rutland@arm.com |
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acquire | ||
add_negative | ||
add_unless | ||
andnot | ||
cmpxchg | ||
dec | ||
dec_and_test | ||
dec_if_positive | ||
dec_unless_positive | ||
fence | ||
fetch_add_unless | ||
inc | ||
inc_and_test | ||
inc_not_zero | ||
inc_unless_negative | ||
read_acquire | ||
release | ||
set_release | ||
sub_and_test | ||
try_cmpxchg | ||
xchg |