locking: Allow obtaining result of arch_mcs_spin_lock_contended

To support upcoming changes that require inspecting the return value
once the conditional waiting loop in arch_mcs_spin_lock_contended
terminates, modify the macro to preserve the result of
smp_cond_load_acquire. This enables checking the return value as needed,
which will help disambiguate the MCS node’s locked state in future
patches.

Reviewed-by: Barret Rhoden <brho@google.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20250316040541.108729-4-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Kumar Kartikeya Dwivedi 2025-03-15 21:05:19 -07:00 committed by Alexei Starovoitov
parent ac08f68f1f
commit c0149a0345
1 changed files with 1 additions and 3 deletions

View File

@ -24,9 +24,7 @@
* spinning, and smp_cond_load_acquire() provides that behavior.
*/
#define arch_mcs_spin_lock_contended(l) \
do { \
smp_cond_load_acquire(l, VAL); \
} while (0)
smp_cond_load_acquire(l, VAL)
#endif
#ifndef arch_mcs_spin_unlock_contended