Peter Xu <pet...@redhat.com> writes:
> This almost reverts commit 923709896b1b01fb982c93492ad01b233e6b6023.
>
> It was needed because the RDMA iochannel on dest QEMU used to only yield
> without monitoring the fd. Now it should be monitored by the same poll()
> similarly on the src QEMU in qemu_rdma_wait_comp_channel(). So even
> without the fd handler, dest QEMU should be able to receive the events.
>
> I tested this by initiating an RDMA migration, then do two things:
>
> - Either does migrate_cancel on src, or,
> - Directly kill destination QEMU
>
> In both cases, the other side of QEMU will be able to receive the
> disconnect event in qemu_rdma_wait_comp_channel() and properly cancel or
> fail the migration.
>
> Signed-off-by: Peter Xu <pet...@redhat.com>
> ---
> migration/rdma.c | 29 +----------------------------
> 1 file changed, 1 insertion(+), 28 deletions(-)
>
> diff --git a/migration/rdma.c b/migration/rdma.c
> index 7751262460..da7fd48bf3 100644
> --- a/migration/rdma.c
> +++ b/migration/rdma.c
> @@ -3045,32 +3045,6 @@ int rdma_control_save_page(QEMUFile *f, ram_addr_t
> block_offset,
>
> static void rdma_accept_incoming_migration(void *opaque);
>
> -static void rdma_cm_poll_handler(void *opaque)
> -{
> - RDMAContext *rdma = opaque;
> - struct rdma_cm_event *cm_event;
> -
> - if (rdma_get_cm_event(rdma->channel, &cm_event) < 0) {
> - error_report("get_cm_event failed %d", errno);
> - return;
> - }
> -
> - if (cm_event->event == RDMA_CM_EVENT_DISCONNECTED ||
> - cm_event->event == RDMA_CM_EVENT_DEVICE_REMOVAL) {
> - if (!rdma->errored &&
> - migration_incoming_get_current()->state !=
> - MIGRATION_STATUS_COMPLETED) {
> - error_report("receive cm event, cm event is %d",
> cm_event->event);
> - rdma->errored = true;
> - if (rdma->return_path) {
> - rdma->return_path->errored = true;
> - }
> - }
> - rdma_ack_cm_event(cm_event);
> - }
> - rdma_ack_cm_event(cm_event);
> -}
> -
> static int qemu_rdma_accept(RDMAContext *rdma)
> {
> Error *err = NULL;
> @@ -3188,8 +3162,7 @@ static int qemu_rdma_accept(RDMAContext *rdma)
> NULL,
> (void *)(intptr_t)rdma->return_path);
> } else {
> - qemu_set_fd_handler(rdma->channel->fd, rdma_cm_poll_handler,
> - NULL, rdma);
> + qemu_set_fd_handler(rdma->channel->fd, NULL, NULL, NULL);
I'm not familiar with this code, but is this left here to remove the
handler? Can't we remove this line altogether?
> }
>
> ret = rdma_accept(rdma->cm_id, &conn_param);
