Hi,
I tried and executed this exciting patches named colo. However this
patch causes abnormal termination in my environment. Although I
think it's a known issue, the details and a presumed origin is
described below:
On 2014/09/23 18:23, Yang Hongyang wrote:
> implement colo save
>
> Signed-off-by: Yang Hongyang
> ---
> migration-colo.c | 60
> +---
> 1 file changed, 53 insertions(+), 7 deletions(-)
>
> diff --git a/migration-colo.c b/migration-colo.c
> index 2e478e9..d99342a 100644
> --- a/migration-colo.c
> +++ b/migration-colo.c
> @@ -13,6 +13,7 @@
> #include "block/coroutine.h"
> #include "hw/qdev-core.h"
> #include "qemu/timer.h"
> +#include "sysemu/sysemu.h"
> #include "migration/migration-colo.h"
> #include
> #include "qemu/error-report.h"
> @@ -106,12 +107,12 @@ static int colo_compare(void)
> return ioctl(comp_fd, COMP_IOCTWAIT, 250);
> }
>
> -static __attribute__((unused)) int colo_compare_flush(void)
> +static int colo_compare_flush(void)
> {
> return ioctl(comp_fd, COMP_IOCTFLUSH, 1);
> }
>
> -static __attribute__((unused)) int colo_compare_resume(void)
> +static int colo_compare_resume(void)
> {
> return ioctl(comp_fd, COMP_IOCTRESUME, 1);
> }
> @@ -200,6 +201,9 @@ static bool colo_is_master(void)
> static int do_colo_transaction(MigrationState *s, QEMUFile *control)
> {
> int ret;
> +uint8_t *buf;
> +size_t size;
> +QEMUFile *trans = NULL;
>
> ret = colo_ctl_put(s->file, COLO_CHECKPOINT_NEW);
> if (ret) {
> @@ -211,30 +215,73 @@ static int do_colo_transaction(MigrationState *s,
> QEMUFile *control)
> goto out;
> }
>
> -/* TODO: suspend and save vm state to colo buffer */
> +/* open colo buffer for write */
> +trans = qemu_bufopen("w", NULL);
> +if (!trans) {
> +error_report("Open colo buffer for write failed");
> +goto out;
> +}
> +
> +/* suspend and save vm state to colo buffer */
> +qemu_mutex_lock_iothread();
> +vm_stop_force_state(RUN_STATE_COLO);
> +qemu_mutex_unlock_iothread();
> +/* Disable block migration */
> +s->params.blk = 0;
> +s->params.shared = 0;
> +qemu_savevm_state_begin(trans, &s->params);
> +qemu_savevm_state_complete(trans);
This line causes aborting Qemu immediately after starting a colo's
migration process. If I'm not mistaken, the cause of aborting is not
getting mutex lock when calling qemu_savevm_state_complete(). The
aborting was resolved by getting mutex lock chen calling
qemu_save_state_complete().
Thanks,
Shunsuke
> +
> +qemu_fflush(trans);
>
> ret = colo_ctl_put(s->file, COLO_CHECKPOINT_SEND);
> if (ret) {
> goto out;
> }
>
> -/* TODO: send vmstate to slave */
> +/* send vmstate to slave */
> +
> +/* we send the total size of the vmstate first */
> +size = qsb_get_length(qemu_buf_get(trans));
> +ret = colo_ctl_put(s->file, size);
> +if (ret) {
> +goto out;
> +}
> +
> +buf = g_malloc(size);
> +qsb_get_buffer(qemu_buf_get(trans), 0, size, &buf);
> +qemu_put_buffer(s->file, buf, size);
> +g_free(buf);
> +ret = qemu_file_get_error(s->file);
> +if (ret < 0) {
> +goto out;
> +}
> +qemu_fflush(s->file);
>
> ret = colo_ctl_get(control, COLO_CHECKPOINT_RECEIVED);
> if (ret) {
> goto out;
> }
>
> -/* TODO: Flush network etc. */
> +/* Flush network etc. */
> +colo_compare_flush();
>
> ret = colo_ctl_get(control, COLO_CHECKPOINT_LOADED);
> if (ret) {
> goto out;
> }
>
> -/* TODO: resume master */
> +colo_compare_resume();
> +ret = 0;
>
> out:
> +if (trans)
> +qemu_fclose(trans);
> +/* resume master */
> +qemu_mutex_lock_iothread();
> +vm_start();
> +qemu_mutex_unlock_iothread();
> +
> return ret;
> }
>
> @@ -289,7 +336,6 @@ static void *colo_thread(void *opaque)
> }
>
> /* start a colo checkpoint */
> -
> if (do_colo_transaction(s, colo_control)) {
> goto out;
> }
>
