f148ae7d36
When switching between AIO contexts we need to me make sure that both recv_coroutine and send_coroutine are not scheduled to run. Otherwise, QEMU may crash while attaching the new context with an error like this one: aio_co_schedule: Co-routine was already scheduled in 'aio_co_schedule' To achieve this we need a local implementation of 'qio_channel_readv_all_eof' named 'nbd_read_eof' (a trick already done by 'nbd/client.c') that allows us to interrupt the operation and to know when recv_coroutine is yielding. With this in place, we delegate detaching the AIO context to the owning context with a BH ('nbd_aio_detach_bh') scheduled using 'aio_wait_bh_oneshot'. This BH signals that we need to quiesce the channel by setting 'client->quiescing' to 'true', and either waits for the coroutine to finish using AIO_WAIT_WHILE or, if it's yielding in 'nbd_read_eof', actively enters the coroutine to interrupt it. RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=1900326 Signed-off-by: Sergio Lopez <slp@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20201214170519.223781-4-slp@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com> |
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client.c | ||
common.c | ||
meson.build | ||
nbd-internal.h | ||
server.c | ||
trace-events | ||
trace.h |