locking/atomic/x86: Introduce arch_atomic64_read_nonatomic() to x86_32

Browse source

Introduce arch_atomic64_read_nonatomic() for 32-bit targets to load
the value from atomic64_t location in a non-atomic way. This
function is intended to be used in cases where a subsequent atomic
operation will handle the torn value, and can be used to prime the
first iteration of unconditional try_cmpxchg() loops.

Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20240410062957.322614-2-ubizjak@gmail.com

...

This commit is contained in:

Uros Bizjak 2024-04-10 08:29:34 +02:00 • committed by Ingo Molnar

parent 276b893049

commit e73c4e34a0

1 changed files with 26 additions and 0 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

26

arch/x86/include/asm/atomic64_32.h

View file