Hi,
On 1/12/2023 12:06 AM, David Howells wrote:
> Hou Tao <[email protected]> wrote:
>
>> clear_bit(FSCACHE_VOLUME_ACQUIRE_PENDING,
>> &cursor->flags);
>> + /*
>> + * Paired with barrier in wait_on_bit(). Check
>> + * wake_up_bit() and waitqueue_active() for details.
>> + */
>> + smp_mb__after_atomic();
>> wake_up_bit(&cursor->flags,
>> FSCACHE_VOLUME_ACQUIRE_PENDING);
> What two values are you applying a partial ordering to?
cursor->flags and wq->head. fscache_wake_pending_volume() will write
cursor->flags and read wq->head through waitqueue_active(), and the wait will
write wq->head then read cursor->flags.
>
> David
>
