On Mon, Sep 04, 2017 at 03:21:08PM +, Bart Van Assche wrote:
> On Sat, 2017-09-02 at 21:08 +0800, Ming Lei wrote:
> > --- a/include/linux/blkdev.h
> > +++ b/include/linux/blkdev.h
> > @@ -565,6 +565,10 @@ struct request_queue {
> >
> > int bypass_depth;
> >
On Sat, 2017-09-02 at 21:08 +0800, Ming Lei wrote:
> --- a/include/linux/blkdev.h
> +++ b/include/linux/blkdev.h
> @@ -565,6 +565,10 @@ struct request_queue {
>
> int bypass_depth;
> atomic_tmq_freeze_depth;
> + spinlock_t
The two APIs are required to allow request allocation of
RQF_PREEMPT when queue is preempt frozen.
The following two points have to be guaranteed for one queue:
1) preempt freezing can be started only after all in-progress
normal & preempt freezings are completed
2) normal freezing can be
