@@ -13,7 +13,16 @@
#include "block/coroutine.h"
#include "qemu/error-report.h"
#include "hw/qdev-core.h"
+#include "qemu/timer.h"
#include "migration/migration-colo.h"
+#include <sys/ioctl.h>
+
+/*
+ * checkpoint timer: unit ms
+ * this is large because COLO checkpoint will mostly depend on
+ * COLO compare module.
+ */
+#define CHKPOINT_TIMER 10000
static QEMUBH *colo_bh;
@@ -22,6 +31,56 @@ bool colo_supported(void)
return true;
}
+/* colo compare */
+#define COMP_IOC_MAGIC 'k'
+#define COMP_IOCTWAIT _IO(COMP_IOC_MAGIC, 0)
+#define COMP_IOCTFLUSH _IO(COMP_IOC_MAGIC, 1)
+#define COMP_IOCTRESUME _IO(COMP_IOC_MAGIC, 2)
+
+#define COMPARE_DEV "/dev/HA_compare"
+/* COLO compare module FD */
+static int comp_fd = -1;
+
+static int colo_compare_init(void)
+{
+ comp_fd = open(COMPARE_DEV, O_RDONLY);
+ if (comp_fd < 0) {
+ return -1;
+ }
+
+ return 0;
+}
+
+static void colo_compare_destroy(void)
+{
+ if (comp_fd >= 0) {
+ close(comp_fd);
+ comp_fd = -1;
+ }
+}
+
+/*
+ * Communicate with COLO Agent through ioctl.
+ * return:
+ * 0: start a checkpoint
+ * other: errno == ETIME or ERESTART, try again
+ * errno == other, error, quit colo save
+ */
+static int colo_compare(void)
+{
+ return ioctl(comp_fd, COMP_IOCTWAIT, 250);
+}
+
+static __attribute__((unused)) int colo_compare_flush(void)
+{
+ return ioctl(comp_fd, COMP_IOCTFLUSH, 1);
+}
+
+static __attribute__((unused)) int colo_compare_resume(void)
+{
+ return ioctl(comp_fd, COMP_IOCTRESUME, 1);
+}
+
/* colo buffer */
#define COLO_BUFFER_BASE_SIZE (1000*1000*4ULL)
@@ -131,15 +190,48 @@ static const QEMUFileOps colo_read_ops = {
static void *colo_thread(void *opaque)
{
MigrationState *s = opaque;
- int dev_hotplug = qdev_hotplug;
+ int dev_hotplug = qdev_hotplug, wait_cp = 0;
+ int64_t start_time = qemu_clock_get_ms(QEMU_CLOCK_HOST);
+ int64_t current_time;
+
+ if (colo_compare_init() < 0) {
+ error_report("Init colo compare error\n");
+ goto out;
+ }
qdev_hotplug = 0;
colo_buffer_init();
- /*TODO: COLO checkpointed save loop*/
+ while (s->state == MIG_STATE_COLO) {
+ /* wait for a colo checkpoint */
+ wait_cp = colo_compare();
+ if (wait_cp) {
+ if (errno != ETIME && errno != ERESTART) {
+ error_report("compare module failed(%s)", strerror(errno));
+ goto out;
+ }
+ /*
+ * no checkpoint is needed, wait for 1ms and then
+ * check if we need checkpoint
+ */
+ current_time = qemu_clock_get_ms(QEMU_CLOCK_HOST);
+ if (current_time - start_time < CHKPOINT_TIMER) {
+ usleep(1000);
+ continue;
+ }
+ }
+
+ /* start a colo checkpoint */
+
+ /*TODO: COLO save */
+ start_time = qemu_clock_get_ms(QEMU_CLOCK_HOST);
+ }
+
+out:
colo_buffer_destroy();
+ colo_compare_destroy();
if (s->state != MIG_STATE_ERROR) {
migrate_set_state(s, MIG_STATE_COLO, MIG_STATE_COMPLETED);
@@ -183,6 +275,17 @@ void colo_init_checkpointer(MigrationState *s)
static Coroutine *colo;
+/*
+ * return:
+ * 0: start a checkpoint
+ * 1: some error happend, exit colo restore
+ */
+static int slave_wait_new_checkpoint(QEMUFile *f)
+{
+ /* TODO: wait checkpoint start command from master */
+ return 1;
+}
+
void colo_process_incoming_checkpoints(QEMUFile *f)
{
int dev_hotplug = qdev_hotplug;
@@ -198,7 +301,13 @@ void colo_process_incoming_checkpoints(QEMUFile *f)
colo_buffer_init();
- /* TODO: COLO checkpointed restore loop */
+ while (true) {
+ if (slave_wait_new_checkpoint(f)) {
+ break;
+ }
+
+ /* TODO: COLO restore */
+ }
colo_buffer_destroy();
colo = NULL;
We use COLO agent to compare the packets returned by Primary VM and Secondary VM, and decide whether to start a checkpoint according to some rules. It is a linux kernel module for host. COLO controller communicate with the agent through ioctl(). Signed-off-by: Yang Hongyang <yanghy@cn.fujitsu.com> --- migration-colo.c | 115 +++++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 112 insertions(+), 3 deletions(-)