On Fri, Sep 06, 2019 at 11:52:10AM +0100, Stefan Hajnoczi wrote: > On Thu, Sep 05, 2019 at 03:48:49PM -0400, Vivek Goyal wrote: > > +static void virtio_fs_drain_queue(struct virtio_fs_vq *fsvq) > > +{ > > + WARN_ON(fsvq->in_flight < 0); > > + > > + /* Wait for in flight requests to finish.*/ > > + while (1) { > > + spin_lock(&fsvq->lock); > > + if (!fsvq->in_flight) { > > + spin_unlock(&fsvq->lock); > > + break; > > + } > > + spin_unlock(&fsvq->lock); > > + usleep_range(1000, 2000); > > + } > > I think all contexts that call this allow sleeping so we could avoid > usleep here. usleep_range() is supposed to be used from non-atomic context. https://github.com/torvalds/linux/blob/master/Documentation/timers/timers-howto.rst What construct you are thinking of? Vivek