* zhanghailiang (zhang.zhanghaili...@huawei.com) wrote:
> Hi Dave,
>
> On 2015/8/27 18:40, Dr. David Alan Gilbert wrote:
> >* 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
> >
> Fixed, i have converted this to QAPI, and some names has been changed too.
>
> Besides, we have decided to respin this series which only including the basic
> periodic checkpoint (Just like MicroCheckpointing, and this periodic mode is
> also what we want to support in COLO.)
> it will be based on Yong Hongyang's netfilter/netbuffer to buffer/release
> net packets.
>
> We have decided to realize the proxy in qemu,
> and there will be a long time for proxy to be ready for merging. So extracting
> the basic periodic checkpoint that not depend on proxy maybe a good idea,
> it will be more easy for test and review, and also can be merged before proxy
> is ready.
OK, yes; do you have a rough feeling for when the version with the proxy in qemu
will arrive?
Dave
>
> >>+ /*
> >>+ * 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?
> >
>
> Fixed, thanks
>
> >>+ }
> >>+
> >>+ *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.
>
> Yes, we should not call exit() in COLO's common path, it will break
> failover. i have fixed it.
>
> >>+
> >>+ trace_colo_ctl_get(COLOCommand_lookup[require]);
> >>+ return ret;
> >
> >That's always 0 ?
> >
>
> I have fixed this helper function.
>
> >>+}
> >>+
> >>+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
> >
> >.
> >
>
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
