Re: [PATCH 4/5] xen/events: unmask a fifo event channel only if it was masked

2020-10-22 Thread Jürgen Groß
On 22.10.20 09:55, Jan Beulich wrote: On 22.10.2020 09:42, Juergen Gross wrote: --- a/drivers/xen/events/events_fifo.c +++ b/drivers/xen/events/events_fifo.c @@ -236,6 +236,9 @@ static bool clear_masked_cond(volatile event_word_t *word) w = *word; + if (!(w & (1 <<

Re: [PATCH 4/5] xen/events: unmask a fifo event channel only if it was masked

2020-10-22 Thread Jan Beulich
On 22.10.2020 09:42, Juergen Gross wrote: > --- a/drivers/xen/events/events_fifo.c > +++ b/drivers/xen/events/events_fifo.c > @@ -236,6 +236,9 @@ static bool clear_masked_cond(volatile event_word_t *word) > > w = *word; > > + if (!(w & (1 << EVTCHN_FIFO_MASKED))) > +

[PATCH 4/5] xen/events: unmask a fifo event channel only if it was masked

2020-10-22 Thread Juergen Gross
Unmasking an event channel with fifo events channels being used can require a hypercall to be made, so try to avoid that by checking whether the event channel was really masked. Suggested-by: Jan Beulich Signed-off-by: Juergen Gross --- drivers/xen/events/events_fifo.c | 3 +++ 1 file changed,