diff options
Diffstat (limited to 'migration.c')
| -rw-r--r-- | migration.c | 337 |
1 files changed, 337 insertions, 0 deletions
diff --git a/migration.c b/migration.c new file mode 100644 index 0000000..190b37e --- /dev/null +++ b/migration.c @@ -0,0 +1,337 @@ +/* + * QEMU live migration + * + * Copyright IBM, Corp. 2008 + * + * Authors: + * Anthony Liguori <aliguori@us.ibm.com> + * + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + * + */ + +#include "qemu-common.h" +#include "migration.h" +#include "monitor.h" +#include "buffered_file.h" +#include "sysemu.h" +#include "block.h" +#include "qemu_socket.h" + +//#define DEBUG_MIGRATION + +#ifdef DEBUG_MIGRATION +#define dprintf(fmt, ...) \ + do { printf("migration: " fmt, ## __VA_ARGS__); } while (0) +#else +#define dprintf(fmt, ...) \ + do { } while (0) +#endif + +/* Migration speed throttling */ +static uint32_t max_throttle = (32 << 20); + +static MigrationState *current_migration; + +void qemu_start_incoming_migration(const char *uri) +{ + const char *p; + + if (strstart(uri, "tcp:", &p)) + tcp_start_incoming_migration(p); +#if !defined(WIN32) + else if (strstart(uri, "exec:", &p)) + exec_start_incoming_migration(p); +#endif + else + fprintf(stderr, "unknown migration protocol: %s\n", uri); +} + +void do_migrate(Monitor *mon, int detach, const char *uri) +{ + MigrationState *s = NULL; + const char *p; + + if (strstart(uri, "tcp:", &p)) + s = tcp_start_outgoing_migration(p, max_throttle, detach); +#if !defined(WIN32) + else if (strstart(uri, "exec:", &p)) + s = exec_start_outgoing_migration(p, max_throttle, detach); +#endif + else + monitor_printf(mon, "unknown migration protocol: %s\n", uri); + + if (s == NULL) + monitor_printf(mon, "migration failed\n"); + else { + if (current_migration) + current_migration->release(current_migration); + + current_migration = s; + } +} + +void do_migrate_cancel(Monitor *mon) +{ + MigrationState *s = current_migration; + + if (s) + s->cancel(s); +} + +void do_migrate_set_speed(Monitor *mon, const char *value) +{ + double d; + char *ptr; + FdMigrationState *s; + + d = strtod(value, &ptr); + switch (*ptr) { + case 'G': case 'g': + d *= 1024; + case 'M': case 'm': + d *= 1024; + case 'K': case 'k': + d *= 1024; + default: + break; + } + + max_throttle = (uint32_t)d; + s = migrate_to_fms(current_migration); + + if (s) { + qemu_file_set_rate_limit(s->file, max_throttle); + } + +} + +/* amount of nanoseconds we are willing to wait for migration to be down. + * the choice of nanoseconds is because it is the maximum resolution that + * get_clock() can achieve. It is an internal measure. All user-visible + * units must be in seconds */ +static uint64_t max_downtime = 30000000; + +uint64_t migrate_max_downtime(void) +{ + return max_downtime; +} + +void do_migrate_set_downtime(Monitor *mon, const char *value) +{ + char *ptr; + double d; + + d = strtod(value, &ptr); + if (!strcmp(ptr,"ms")) { + d *= 1000000; + } else if (!strcmp(ptr,"us")) { + d *= 1000; + } else if (!strcmp(ptr,"ns")) { + } else { + /* all else considered to be seconds */ + d *= 1000000000; + } + + max_downtime = (uint64_t)d; +} + +void do_info_migrate(Monitor *mon) +{ + MigrationState *s = current_migration; + + if (s) { + monitor_printf(mon, "Migration status: "); + switch (s->get_status(s)) { + case MIG_STATE_ACTIVE: + monitor_printf(mon, "active\n"); + monitor_printf(mon, "transferred ram: %" PRIu64 " kbytes\n", ram_bytes_transferred() >> 10); + monitor_printf(mon, "remaining ram: %" PRIu64 " kbytes\n", ram_bytes_remaining() >> 10); + monitor_printf(mon, "total ram: %" PRIu64 " kbytes\n", ram_bytes_total() >> 10); + break; + case MIG_STATE_COMPLETED: + monitor_printf(mon, "completed\n"); + break; + case MIG_STATE_ERROR: + monitor_printf(mon, "failed\n"); + break; + case MIG_STATE_CANCELLED: + monitor_printf(mon, "cancelled\n"); + break; + } + } +} + +/* shared migration helpers */ + +void migrate_fd_monitor_suspend(FdMigrationState *s) +{ + s->mon_resume = cur_mon; + if (monitor_suspend(cur_mon) == 0) + dprintf("suspending monitor\n"); + else + monitor_printf(cur_mon, "terminal does not allow synchronous " + "migration, continuing detached\n"); +} + +void migrate_fd_error(FdMigrationState *s) +{ + dprintf("setting error state\n"); + s->state = MIG_STATE_ERROR; + migrate_fd_cleanup(s); +} + +void migrate_fd_cleanup(FdMigrationState *s) +{ + qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL); + + if (s->file) { + dprintf("closing file\n"); + qemu_fclose(s->file); + } + + if (s->fd != -1) + close(s->fd); + + /* Don't resume monitor until we've flushed all of the buffers */ + if (s->mon_resume) + monitor_resume(s->mon_resume); + + s->fd = -1; +} + +void migrate_fd_put_notify(void *opaque) +{ + FdMigrationState *s = opaque; + + qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL); + qemu_file_put_notify(s->file); +} + +ssize_t migrate_fd_put_buffer(void *opaque, const void *data, size_t size) +{ + FdMigrationState *s = opaque; + ssize_t ret; + + do { + ret = s->write(s, data, size); + } while (ret == -1 && ((s->get_error(s)) == EINTR)); + + if (ret == -1) + ret = -(s->get_error(s)); + + if (ret == -EAGAIN) + qemu_set_fd_handler2(s->fd, NULL, NULL, migrate_fd_put_notify, s); + + return ret; +} + +void migrate_fd_connect(FdMigrationState *s) +{ + int ret; + + s->file = qemu_fopen_ops_buffered(s, + s->bandwidth_limit, + migrate_fd_put_buffer, + migrate_fd_put_ready, + migrate_fd_wait_for_unfreeze, + migrate_fd_close); + + dprintf("beginning savevm\n"); + ret = qemu_savevm_state_begin(s->file); + if (ret < 0) { + dprintf("failed, %d\n", ret); + migrate_fd_error(s); + return; + } + + migrate_fd_put_ready(s); +} + +void migrate_fd_put_ready(void *opaque) +{ + FdMigrationState *s = opaque; + + if (s->state != MIG_STATE_ACTIVE) { + dprintf("put_ready returning because of non-active state\n"); + return; + } + + dprintf("iterate\n"); + if (qemu_savevm_state_iterate(s->file) == 1) { + int state; + dprintf("done iterating\n"); + vm_stop(0); + + bdrv_flush_all(); + if ((qemu_savevm_state_complete(s->file)) < 0) { + vm_start(); + state = MIG_STATE_ERROR; + } else { + state = MIG_STATE_COMPLETED; + } + migrate_fd_cleanup(s); + s->state = state; + } +} + +int migrate_fd_get_status(MigrationState *mig_state) +{ + FdMigrationState *s = migrate_to_fms(mig_state); + return s->state; +} + +void migrate_fd_cancel(MigrationState *mig_state) +{ + FdMigrationState *s = migrate_to_fms(mig_state); + + if (s->state != MIG_STATE_ACTIVE) + return; + + dprintf("cancelling migration\n"); + + s->state = MIG_STATE_CANCELLED; + + migrate_fd_cleanup(s); +} + +void migrate_fd_release(MigrationState *mig_state) +{ + FdMigrationState *s = migrate_to_fms(mig_state); + + dprintf("releasing state\n"); + + if (s->state == MIG_STATE_ACTIVE) { + s->state = MIG_STATE_CANCELLED; + migrate_fd_cleanup(s); + } + free(s); +} + +void migrate_fd_wait_for_unfreeze(void *opaque) +{ + FdMigrationState *s = opaque; + int ret; + + dprintf("wait for unfreeze\n"); + if (s->state != MIG_STATE_ACTIVE) + return; + + do { + fd_set wfds; + + FD_ZERO(&wfds); + FD_SET(s->fd, &wfds); + + ret = select(s->fd + 1, NULL, &wfds, NULL, NULL); + } while (ret == -1 && (s->get_error(s)) == EINTR); +} + +int migrate_fd_close(void *opaque) +{ + FdMigrationState *s = opaque; + + qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL); + return s->close(s); +} |