On 09/03, Peter Zijlstra wrote: > > On Wed, Sep 03, 2014 at 03:36:40PM +0200, Oleg Nesterov wrote: > > > > // Ensure that the previous __set_current_state(RUNNING) can't > > // leak after spin_unlock_wait() > > smp_mb(); > > spin_unlock_wait(); > > // Another mb to ensure this too can't be reordered with unlock_wait > > set_current_state(TASK_DEAD); > > > > What do you think looks better? > > spin_unlock_wait() would be a control dependency right? Therefore that > store could not creep up anyhow.
Hmm. indeed, thanks! This probably means that task_work_run() can use rmb() instead of mb(). What I can't understand is do we still need a compiler barrier or not. Probably "in theory yes" ? Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
