* zhanghailiang (zhang.zhanghaili...@huawei.com) wrote:
> We need communications protocol of user-defined to control the checkpoint
> process.
>
> The new checkpoint request is started by Primary VM, and the interactive
> process
> like below:
> Checkpoint synchronizing points,
>
> Primary Secondary
> NEW @
> Suspend
> SUSPENDED @
> Suspend&Save state
> SEND @
> Send state Receive state
> RECEIVED @
> Flush network Load state
> LOADED @
> Resume Resume
>
> Start Comparing
> NOTE:
> 1) '@' who sends the message
> 2) Every sync-point is synchronized by two sides with only
> one handshake(single direction) for low-latency.
> If more strict synchronization is required, a opposite direction
> sync-point should be added.
> 3) Since sync-points are single direction, the remote side may
> go forward a lot when this side just receives the sync-point.
>
> Signed-off-by: Yang Hongyang <yan...@cn.fujitsu.com>
> Signed-off-by: zhanghailiang <zhang.zhanghaili...@huawei.com>
> Signed-off-by: Li Zhijian <lizhij...@cn.fujitsu.com>
> Signed-off-by: Gonglei <arei.gong...@huawei.com>
> ---
> migration/colo.c | 248
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++-
> trace-events | 3 +-
> 2 files changed, 248 insertions(+), 3 deletions(-)
>
> diff --git a/migration/colo.c b/migration/colo.c
> index 364e0dd..4ba6f65 100644
> --- a/migration/colo.c
> +++ b/migration/colo.c
> @@ -14,6 +14,55 @@
> #include "migration/colo.h"
> #include "trace.h"
> #include "qemu/error-report.h"
> +#include "qemu/sockets.h"
> +
> +/* Fix me: Convert to use QAPI */
> +typedef enum COLOCommand {
> + COLO_CHECPOINT_READY = 0x46,
Typo: CHEC*K*POINT
> + /*
> + * Checkpoint synchronizing points.
> + *
> + * Primary Secondary
> + * NEW @
> + * Suspend
> + * SUSPENDED @
> + * Suspend&Save state
> + * SEND @
> + * Send state Receive state
> + * RECEIVED @
> + * Flush network Load state
> + * LOADED @
> + * Resume Resume
> + *
> + * Start Comparing
> + * NOTE:
> + * 1) '@' who sends the message
> + * 2) Every sync-point is synchronized by two sides with only
> + * one handshake(single direction) for low-latency.
> + * If more strict synchronization is required, a opposite direction
> + * sync-point should be added.
> + * 3) Since sync-points are single direction, the remote side may
> + * go forward a lot when this side just receives the sync-point.
> + */
> + COLO_CHECKPOINT_NEW,
> + COLO_CHECKPOINT_SUSPENDED,
> + COLO_CHECKPOINT_SEND,
> + COLO_CHECKPOINT_RECEIVED,
> + COLO_CHECKPOINT_LOADED,
> +
> + COLO_CHECKPOINT_MAX
> +} COLOCommand;
> +
> +const char * const COLOCommand_lookup[] = {
Unneeded ' ' after the *.
> + [COLO_CHECPOINT_READY] = "checkpoint-ready",
> + [COLO_CHECKPOINT_NEW] = "checkpoint-new",
> + [COLO_CHECKPOINT_SUSPENDED] = "checkpoint-suspend",
> + [COLO_CHECKPOINT_SEND] = "checheckpoint-send",
> + [COLO_CHECKPOINT_RECEIVED] = "checkpoint-received",
> + [COLO_CHECKPOINT_LOADED] = "checkpoint-loaded",
> + [COLO_CHECKPOINT_MAX] = NULL,
> +};
>
> static QEMUBH *colo_bh;
>
> @@ -36,20 +85,137 @@ bool migration_incoming_in_colo_state(void)
> return (mis && (mis->state == MIGRATION_STATUS_COLO));
> }
>
> +/* colo checkpoint control helper */
> +static int colo_ctl_put(QEMUFile *f, uint64_t request)
> +{
> + int ret = 0;
> +
> + qemu_put_be64(f, request);
> + qemu_fflush(f);
> +
> + ret = qemu_file_get_error(f);
> + if (request < COLO_CHECKPOINT_MAX) {
> + trace_colo_ctl_put(COLOCommand_lookup[request]);
> + }
> + return ret;
> +}
> +
> +static int colo_ctl_get_value(QEMUFile *f, uint64_t *value)
> +{
> + int ret = 0;
> + uint64_t temp;
> +
> + temp = qemu_get_be64(f);
> +
> + ret = qemu_file_get_error(f);
> + if (ret < 0) {
> + return -1;
Why not just return ret rather than -1?
> + }
> +
> + *value = temp;
> + return 0;
> +}
> +
> +static int colo_ctl_get(QEMUFile *f, uint64_t require)
> +{
> + int ret;
> + uint64_t value;
> +
> + ret = colo_ctl_get_value(f, &value);
> + if (ret < 0) {
> + return ret;
> + }
> +
> + if (value != require) {
> + error_report("unexpected state! expected: %"PRIu64
> + ", received: %"PRIu64, require, value);
> + exit(1);
> + }
Do you really want to exit? If you change that to something like
return -EINVAL;
then if it happens on the primary side, the primary side would
survive.
> +
> + trace_colo_ctl_get(COLOCommand_lookup[require]);
> + return ret;
That's always 0 ?
> +}
> +
> +static int colo_do_checkpoint_transaction(MigrationState *s, QEMUFile
> *control)
> +{
> + int ret;
> +
> + ret = colo_ctl_put(s->file, COLO_CHECKPOINT_NEW);
> + if (ret < 0) {
> + goto out;
> + }
> +
> + ret = colo_ctl_get(control, COLO_CHECKPOINT_SUSPENDED);
> + if (ret < 0) {
> + goto out;
> + }
> +
> + /* TODO: suspend and save vm state to colo buffer */
> +
> + ret = colo_ctl_put(s->file, COLO_CHECKPOINT_SEND);
> + if (ret < 0) {
> + goto out;
> + }
> +
> + /* TODO: send vmstate to Secondary */
> +
> + ret = colo_ctl_get(control, COLO_CHECKPOINT_RECEIVED);
> + if (ret < 0) {
> + goto out;
> + }
> +
> + ret = colo_ctl_get(control, COLO_CHECKPOINT_LOADED);
> + if (ret < 0) {
> + goto out;
> + }
> +
> + /* TODO: resume Primary */
> +
> +out:
> + return ret;
> +}
> +
> static void *colo_thread(void *opaque)
> {
> MigrationState *s = opaque;
> + QEMUFile *colo_control = NULL;
> + int ret;
> +
> + colo_control = qemu_fopen_socket(qemu_get_fd(s->file), "rb");
> + if (!colo_control) {
> + error_report("Open colo_control failed!");
> + goto out;
> + }
> +
> + /*
> + * Wait for Secondary finish loading vm states and enter COLO
> + * restore.
> + */
> + ret = colo_ctl_get(colo_control, COLO_CHECPOINT_READY);
> + if (ret < 0) {
> + goto out;
> + }
>
> qemu_mutex_lock_iothread();
> vm_start();
> qemu_mutex_unlock_iothread();
> trace_colo_vm_state_change("stop", "run");
>
> - /*TODO: COLO checkpoint savevm loop*/
> + while (s->state == MIGRATION_STATUS_COLO) {
> + /* start a colo checkpoint */
> + if (colo_do_checkpoint_transaction(s, colo_control)) {
> + goto out;
> + }
> + }
>
> +out:
> migrate_set_state(&s->state, MIGRATION_STATUS_COLO,
> MIGRATION_STATUS_COMPLETED);
>
> + if (colo_control) {
> + qemu_fclose(colo_control);
> + }
> +
> qemu_mutex_lock_iothread();
> qemu_bh_schedule(s->cleanup_bh);
> qemu_mutex_unlock_iothread();
> @@ -83,15 +249,93 @@ void colo_init_checkpointer(MigrationState *s)
> qemu_bh_schedule(colo_bh);
> }
>
> +/*
> + * return:
> + * 0: start a checkpoint
> + * -1: some error happened, exit colo restore
> + */
> +static int colo_wait_handle_cmd(QEMUFile *f, int *checkpoint_request)
> +{
> + int ret;
> + uint64_t cmd;
> +
> + ret = colo_ctl_get_value(f, &cmd);
> + if (ret < 0) {
> + return -1;
return ret ?
> + }
> +
> + switch (cmd) {
> + case COLO_CHECKPOINT_NEW:
> + *checkpoint_request = 1;
> + return 0;
> + default:
> + return -1;
> + }
> +}
> +
> void *colo_process_incoming_checkpoints(void *opaque)
> {
> MigrationIncomingState *mis = opaque;
> + QEMUFile *f = mis->file;
> + int fd = qemu_get_fd(f);
> + QEMUFile *ctl = NULL;
> + int ret;
>
> migrate_set_state(&mis->state, MIGRATION_STATUS_ACTIVE,
> MIGRATION_STATUS_COLO);
>
> - /* TODO: COLO checkpoint restore loop */
> + ctl = qemu_fopen_socket(fd, "wb");
> + if (!ctl) {
> + error_report("Can't open incoming channel!");
> + goto out;
> + }
> + ret = colo_ctl_put(ctl, COLO_CHECPOINT_READY);
> + if (ret < 0) {
> + goto out;
> + }
> + /* TODO: in COLO mode, Secondary is runing, so start the vm */
> + while (mis->state == MIGRATION_STATUS_COLO) {
> + int request = 0;
> + int ret = colo_wait_handle_cmd(f, &request);
> +
> + if (ret < 0) {
> + break;
> + } else {
> + if (!request) {
> + continue;
> + }
> + }
>
> + /* TODO: suspend guest */
> + ret = colo_ctl_put(ctl, COLO_CHECKPOINT_SUSPENDED);
> + if (ret < 0) {
> + goto out;
> + }
> +
> + ret = colo_ctl_get(f, COLO_CHECKPOINT_SEND);
> + if (ret < 0) {
> + goto out;
> + }
> +
> + /* TODO: read migration data into colo buffer */
> +
> + ret = colo_ctl_put(ctl, COLO_CHECKPOINT_RECEIVED);
> + if (ret < 0) {
> + goto out;
> + }
> +
> + /* TODO: load vm state */
> +
> + ret = colo_ctl_put(ctl, COLO_CHECKPOINT_LOADED);
> + if (ret < 0) {
> + goto out;
> + }
> +}
> +
> +out:
> + if (ctl) {
> + qemu_fclose(ctl);
> + }
> migration_incoming_exit_colo();
>
> return NULL;
> diff --git a/trace-events b/trace-events
> index 025d71c..4487633 100644
> --- a/trace-events
> +++ b/trace-events
> @@ -1473,7 +1473,8 @@
> rdma_start_outgoing_migration_after_rdma_source_init(void) ""
>
> # migration/colo.c
> colo_vm_state_change(const char *old, const char *new) "Change '%s' => '%s'"
> -colo_receive_message(const char *msg) "Receive '%s'"
> +colo_ctl_put(const char *msg) "Send '%s'"
> +colo_ctl_get(const char *msg) "Receive '%s'"
>
> # kvm-all.c
> kvm_ioctl(int type, void *arg) "type 0x%x, arg %p"
> --
> 1.8.3.1
>
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
