[PATCH -v2 2/6] locking: Introduce cmpwait()

Provide the cmpwait() primitive, which will 'spin' wait for a variable to change and use it to implement smp_cond_load_acquire(). This primitive can be implemented with hardware assist on some platforms (ARM64, x86). Suggested-by: Will Deacon Signed-off-by: Peter Zijlstra

[PATCH -v2 2/6] locking: Introduce cmpwait()

Provide the cmpwait() primitive, which will 'spin' wait for a variable to change and use it to implement smp_cond_load_acquire(). This primitive can be implemented with hardware assist on some platforms (ARM64, x86). Suggested-by: Will Deacon Signed-off-by: Peter Zijlstra (Intel) ---