Peter Xu <[email protected]> writes:
> Now after threadified dest VM load during precopy, we will always in a
> thread context rather than within a coroutine. We can remove this path
> now.
>
> With that, migration_started_on_destination can go away too.
>
> Signed-off-by: Peter Xu <[email protected]>
> ---
> migration/rdma.c | 102 +++++++++++++++++++----------------------------
> 1 file changed, 41 insertions(+), 61 deletions(-)
>
> diff --git a/migration/rdma.c b/migration/rdma.c
> index 2b995513aa..7751262460 100644
> --- a/migration/rdma.c
> +++ b/migration/rdma.c
> @@ -29,7 +29,6 @@
> #include "qemu/rcu.h"
> #include "qemu/sockets.h"
> #include "qemu/bitmap.h"
> -#include "qemu/coroutine.h"
> #include "system/memory.h"
> #include <sys/socket.h>
> #include <netdb.h>
> @@ -357,13 +356,6 @@ typedef struct RDMAContext {
> /* Index of the next RAMBlock received during block registration */
> unsigned int next_src_index;
>
> - /*
> - * Migration on *destination* started.
> - * Then use coroutine yield function.
> - * Source runs in a thread, so we don't care.
> - */
> - int migration_started_on_destination;
> -
> int total_registrations;
> int total_writes;
>
> @@ -1353,66 +1345,55 @@ static int qemu_rdma_wait_comp_channel(RDMAContext
> *rdma,
> struct rdma_cm_event *cm_event;
>
> /*
> - * Coroutine doesn't start until migration_fd_process_incoming()
> - * so don't yield unless we know we're running inside of a coroutine.
> + * This is the source or dest side, either during precopy or
> + * postcopy. We're always in a separate thread when reaching here.
> + * Poll the fd. We need to be able to handle 'cancel' or an error
> + * without hanging forever.
> */
> - if (rdma->migration_started_on_destination &&
> - migration_incoming_get_current()->state == MIGRATION_STATUS_ACTIVE &&
> - qemu_in_coroutine()) {
> - yield_until_fd_readable(comp_channel->fd);
> - } else {
> - /* This is the source side, we're in a separate thread
> - * or destination prior to migration_fd_process_incoming()
> - * after postcopy, the destination also in a separate thread.
> - * we can't yield; so we have to poll the fd.
> - * But we need to be able to handle 'cancel' or an error
> - * without hanging forever.
> - */
> - while (!rdma->errored && !rdma->received_error) {
> - GPollFD pfds[2];
> - pfds[0].fd = comp_channel->fd;
> - pfds[0].events = G_IO_IN | G_IO_HUP | G_IO_ERR;
> - pfds[0].revents = 0;
> -
> - pfds[1].fd = rdma->channel->fd;
> - pfds[1].events = G_IO_IN | G_IO_HUP | G_IO_ERR;
> - pfds[1].revents = 0;
> -
> - /* 0.1s timeout, should be fine for a 'cancel' */
> - switch (qemu_poll_ns(pfds, 2, 100 * 1000 * 1000)) {
> - case 2:
> - case 1: /* fd active */
> - if (pfds[0].revents) {
> - return 0;
> - }
> + while (!rdma->errored && !rdma->received_error) {
> + GPollFD pfds[2];
> + pfds[0].fd = comp_channel->fd;
> + pfds[0].events = G_IO_IN | G_IO_HUP | G_IO_ERR;
> + pfds[0].revents = 0;
> +
> + pfds[1].fd = rdma->channel->fd;
> + pfds[1].events = G_IO_IN | G_IO_HUP | G_IO_ERR;
> + pfds[1].revents = 0;
> +
> + /* 0.1s timeout, should be fine for a 'cancel' */
> + switch (qemu_poll_ns(pfds, 2, 100 * 1000 * 1000)) {
Don't glib have facilities for polling? Isn't this what
qio_channel_rdma_create_watch() is for already?
> + case 2:
> + case 1: /* fd active */
> + if (pfds[0].revents) {
> + return 0;
> + }
>
> - if (pfds[1].revents) {
> - if (rdma_get_cm_event(rdma->channel, &cm_event) < 0) {
> - return -1;
> - }
> + if (pfds[1].revents) {
> + if (rdma_get_cm_event(rdma->channel, &cm_event) < 0) {
> + return -1;
> + }
>
> - if (cm_event->event == RDMA_CM_EVENT_DISCONNECTED ||
> - cm_event->event == RDMA_CM_EVENT_DEVICE_REMOVAL) {
> - rdma_ack_cm_event(cm_event);
> - return -1;
> - }
> + if (cm_event->event == RDMA_CM_EVENT_DISCONNECTED ||
> + cm_event->event == RDMA_CM_EVENT_DEVICE_REMOVAL) {
> rdma_ack_cm_event(cm_event);
> + return -1;
> }
> - break;
> + rdma_ack_cm_event(cm_event);
> + }
> + break;
>
> - case 0: /* Timeout, go around again */
> - break;
> + case 0: /* Timeout, go around again */
> + break;
>
> - default: /* Error of some type -
> - * I don't trust errno from qemu_poll_ns
> - */
> - return -1;
> - }
> + default: /* Error of some type -
> + * I don't trust errno from qemu_poll_ns
> + */
> + return -1;
> + }
>
> - if (migrate_get_current()->state == MIGRATION_STATUS_CANCELLING)
> {
> - /* Bail out and let the cancellation happen */
> - return -1;
> - }
> + if (migrate_get_current()->state == MIGRATION_STATUS_CANCELLING) {
> + /* Bail out and let the cancellation happen */
> + return -1;
> }
> }
>
> @@ -3817,7 +3798,6 @@ static void rdma_accept_incoming_migration(void *opaque)
> return;
> }
>
> - rdma->migration_started_on_destination = 1;
> migration_fd_process_incoming(f);
> }
