[PATCH] alpha: Select ARCH_SUPPORTS_ATOMIC_RMW
Matt Turner <[email protected]>
| Newsgroups | org.kernel.vger.linux-alpha,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
Alpha has native LL/SC instructions (LDL_L/STL_C, LDQ_L/STQ_C) that provide atomic read-modify-write capability, and already selects ARCH_HAVE_NMI_SAFE_CMPXCHG. 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 <[email protected]> --- 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