On 02/20/2014 08:59 PM, Tejun Heo wrote:
Hello,
On Thu, Feb 20, 2014 at 08:44:46PM -0500, Peter Hurley wrote:
+static void fw_device_workfn(struct work_struct *work)
+{
+ struct fw_device *device = container_of(to_delayed_work(work),
+ struct fw_device, work);
I think this needs an smp_rmb() here.
The patch is equivalent transformation and the whole thing is
guaranteed to have gone through pool->lock. No explicit rmb
necessary.
The spin_unlock_irq(&pool->lock) only guarantees completion of
memory operations _before_ the unlock; memory operations which occur
_after_ the unlock may be speculated before the unlock.
IOW, unlock is not a memory barrier for operations that occur after.
IOW, the beginning of the work function should act like a barrier in
the same way that queue_work_on() (et. al.) already does.
workqueue already has enough barriers; otherwise, the whole kernel
would have crumbled long time ago.
See above.
Regards,
Peter Hurley
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
