[PATCH v3] MCS spinlock: Use smp_cond_load_acquire() in spin loop

This patch applies on top of: git://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git locking/rfc --- For qspinlocks on ARM64, we would like to use WFE instead of purely spinning. Qspinlocks internally have lock contenders spin on an MCS lock. Update arch_mcs_spin_lock_contended() such

[PATCH v3] MCS spinlock: Use smp_cond_load_acquire() in spin loop

This patch applies on top of: git://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git locking/rfc --- For qspinlocks on ARM64, we would like to use WFE instead of purely spinning. Qspinlocks internally have lock contenders spin on an MCS lock. Update arch_mcs_spin_lock_contended() such