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Selecting ARCH_SUPPORTS_ATOMIC_RMW enables MUTEX_SPIN_ON_OWNER and RWSEM_SPIN_ON_OWNER on SMP, allowing optimistic spinning on contended locks rather than immediately sleeping. Assisted-by: Claude:claude-opus-4-6 Signed-off-by: Matt Turner --- arch/alpha/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git ./arch/alpha/Kconfig ./arch/alpha/Kconfig index 4329743757e3..57c91ed67b71 100644 --- ./arch/alpha/Kconfig +++ ./arch/alpha/Kconfig @@ -10,6 +10,7 @@ config ALPHA select ARCH_MODULE_NEEDS_WEAK_PER_CPU if SMP select ARCH_NO_PREEMPT select ARCH_NO_SG_CHAIN + select ARCH_SUPPORTS_ATOMIC_RMW select ARCH_SUPPORTS_PAGE_TABLE_CHECK select ARCH_USE_CMPXCHG_LOCKREF select FORCE_PCI -- 2.52.0