On Tue, Dec 14, 2021 at 8:40 AM Durrant, Paul <xadimgnik@gmail.com> wrote:
On 10/12/2021 11:34, Jason Andryuk wrote:
commit f37f29d31488 "xen: slightly simplify bufioreq handling" hard
coded setting req.count = 1 during initial field setup before the main
loop. This missed a subtlety that an early exit from the loop when
there are no ioreqs to process, would have req.count == 0 for the return
value. handle_buffered_io() would then remove state->buffered_io_timer.
Instead handle_buffered_iopage() is basically always returning true and
handle_buffered_io() always re-setting the timer.
Restore the disabling of the timer by introducing a new handled_ioreq
boolean and use as the return value. The named variable will more
clearly show the intent of the code.
Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Thanks, Paul.
What is the next step for getting this into QEMU?
To re-state more plainly, this patch fixes a bug to let QEMU go idle
for longer stretches of time. Without it, buffer_io_timer continues
to re-arm and fire every 100ms even if there is nothing to do.
Regards,
Jason