Am 21.11.2022 um 16:52 hat Emanuele Giuseppe Esposito geschrieben: > Am 21/11/2022 um 16:30 schrieb Kevin Wolf: > > Am 16.11.2022 um 13:22 hat Emanuele Giuseppe Esposito geschrieben: > >> Basically BdrvPollCo->bs is only used by bdrv_poll_co(), and the > >> functions that it uses are both using bdrv_get_aio_context, that > >> defaults to qemu_get_aio_context() if bs is NULL. > >> > >> Therefore pass NULL to BdrvPollCo to automatically generate a function > >> that create and runs a coroutine in the main loop. > >> > >> Signed-off-by: Emanuele Giuseppe Esposito <eespo...@redhat.com> > > > > It happens to work, but it's kind of ugly to call bdrv_coroutine_enter() > > and BDRV_POLL_WHILE() with a NULL bs. > > > > How hard would it be to generate code that doesn't use these functions, > > but directly aio_co_enter() and AIO_WAIT_WHILE() for wrappers that are > > not related to a BDS? > > > > At this point, I would get rid of s->poll_state.bs and instead use > s->poll_state.aio_context. Then call directly aio_co_enter and > AIO_WAIT_WHILE, as you suggested but just everywhere, without > differentiating the cases.
Oh, yes, that's better. > Then we would have something similar to what it is currently done with bs: > > if t == 'BlockDriverState *': > bs = 'bdrv_get_aio_context(bs)' > elif t == 'BdrvChild *': > bs = 'bdrv_get_aio_context(child->bs)' > elif t == 'BlockBackend *': > bs = 'bdrv_get_aio_context(blk_bs(blk))' blk_get_aio_context(blk) seems more correct. > else: > bs = 'qemu_get_aio_context()' > > I haven't tried it yet, but it should work. Kevin
