| Message ID | 40805800eed9ed08f44b088e8a50f71c69e6cac4.1358920534.git.hutao@cn.fujitsu.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jan 23, 2013 at 03:19:22PM +0800, Hu Tao wrote: > This patch enables preservation of cpu runstate during save/load vm. > So when a vm is restored from snapshot, the cpu runstate is restored, > too. > > See following example: > > # save two vms: one is running, the other is paused > (qemu) info status > VM status: running > (qemu) savevm running > (qemu) stop > (qemu) info status > VM status: paused > (qemu) savevm paused > > # restore the one running > (qemu) info status > VM status: paused > (qemu) loadvm running > (qemu) info status > VM status: running > > # restore the one paused > (qemu) loadvm paused > (qemu) info status > VM status: paused > (qemu) cont > (qemu)info status > VM status: running > > > Signed-off-by: Hu Tao <hutao@cn.fujitsu.com> Lack of pause state on guest images is annoying. Fail to see why the panic feature depends on preservation of cpu runstate. > include/sysemu/sysemu.h | 2 ++ > migration.c | 6 +----- > monitor.c | 5 ++--- > savevm.c | 1 + > vl.c | 34 ++++++++++++++++++++++++++++++++++ > 5 files changed, 40 insertions(+), 8 deletions(-) > > diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h > index 337ce7d..7a69fde 100644 > --- a/include/sysemu/sysemu.h > +++ b/include/sysemu/sysemu.h > @@ -19,6 +19,8 @@ extern uint8_t qemu_uuid[]; > int qemu_uuid_parse(const char *str, uint8_t *uuid); > #define UUID_FMT "%02hhx%02hhx%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx" > > +void save_run_state(void); > +void load_run_state(void); > bool runstate_check(RunState state); > void runstate_set(RunState new_state); > int runstate_is_running(void); > diff --git a/migration.c b/migration.c > index 77c1971..f96cfd6 100644 > --- a/migration.c > +++ b/migration.c > @@ -108,11 +108,7 @@ static void process_incoming_migration_co(void *opaque) > /* Make sure all file formats flush their mutable metadata */ > bdrv_invalidate_cache_all(); > > - if (autostart) { > - vm_start(); > - } else { > - runstate_set(RUN_STATE_PAUSED); > - } > + load_run_state(); > } > > static void enter_migration_coroutine(void *opaque) > diff --git a/monitor.c b/monitor.c > index 20bd19b..9381ed0 100644 > --- a/monitor.c > +++ b/monitor.c > @@ -2059,13 +2059,12 @@ void qmp_closefd(const char *fdname, Error **errp) > > static void do_loadvm(Monitor *mon, const QDict *qdict) > { > - int saved_vm_running = runstate_is_running(); > const char *name = qdict_get_str(qdict, "name"); > > vm_stop(RUN_STATE_RESTORE_VM); > > - if (load_vmstate(name) == 0 && saved_vm_running) { > - vm_start(); > + if (load_vmstate(name) == 0) { > + load_run_state(); > } > } > > diff --git a/savevm.c b/savevm.c > index 304d1ef..10f1d56 100644 > --- a/savevm.c > +++ b/savevm.c > @@ -2112,6 +2112,7 @@ void do_savevm(Monitor *mon, const QDict *qdict) > } > > saved_vm_running = runstate_is_running(); > + save_run_state(); > vm_stop(RUN_STATE_SAVE_VM); > > memset(sn, 0, sizeof(*sn)); > diff --git a/vl.c b/vl.c > index 4ee1302..b0bcf1e 100644 > --- a/vl.c > +++ b/vl.c > @@ -520,6 +520,7 @@ static int default_driver_check(QemuOpts *opts, void *opaque) > /* QEMU state */ > > static RunState current_run_state = RUN_STATE_PRELAUNCH; > +static RunState saved_run_state = RUN_STATE_PRELAUNCH; > > typedef struct { > RunState from; > @@ -543,6 +544,7 @@ static const RunStateTransition runstate_transitions_def[] = { > { RUN_STATE_PAUSED, RUN_STATE_FINISH_MIGRATE }, > > { RUN_STATE_POSTMIGRATE, RUN_STATE_RUNNING }, > + { RUN_STATE_POSTMIGRATE, RUN_STATE_PAUSED }, > { RUN_STATE_POSTMIGRATE, RUN_STATE_FINISH_MIGRATE }, > > { RUN_STATE_PRELAUNCH, RUN_STATE_RUNNING }, > @@ -553,6 +555,7 @@ static const RunStateTransition runstate_transitions_def[] = { > { RUN_STATE_FINISH_MIGRATE, RUN_STATE_POSTMIGRATE }, > > { RUN_STATE_RESTORE_VM, RUN_STATE_RUNNING }, > + { RUN_STATE_RESTORE_VM, RUN_STATE_PAUSED }, > > { RUN_STATE_RUNNING, RUN_STATE_DEBUG }, > { RUN_STATE_RUNNING, RUN_STATE_INTERNAL_ERROR }, > @@ -582,11 +585,39 @@ static const RunStateTransition runstate_transitions_def[] = { > > static bool runstate_valid_transitions[RUN_STATE_MAX][RUN_STATE_MAX]; > > +void save_run_state(void) > +{ > + saved_run_state = current_run_state; > +} > + > +void load_run_state(void) > +{ > + if (saved_run_state == RUN_STATE_RUNNING) { > + vm_start(); > + } else if (!runstate_check(saved_run_state)) { > + runstate_set(saved_run_state); > + } else { > + ; /* leave unchanged */ > + } > +} > + > bool runstate_check(RunState state) > { > return current_run_state == state; > } > > +static void runstate_save(QEMUFile *f, void *opaque) > +{ > + qemu_put_byte(f, saved_run_state); > +} > + > +static int runstate_load(QEMUFile *f, void *opaque, int version_id) > +{ > + saved_run_state = qemu_get_byte(f); > + > + return 0; > +} This breaks loading images without support for runstate information. Is it possible to overcome this limitation? Would be happier if this patch could be debated on QEMU list. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Feb 07, 2013 at 11:45:34PM -0200, Marcelo Tosatti wrote: > On Wed, Jan 23, 2013 at 03:19:22PM +0800, Hu Tao wrote: > > This patch enables preservation of cpu runstate during save/load vm. > > So when a vm is restored from snapshot, the cpu runstate is restored, > > too. > > > > See following example: > > > > # save two vms: one is running, the other is paused > > (qemu) info status > > VM status: running > > (qemu) savevm running > > (qemu) stop > > (qemu) info status > > VM status: paused > > (qemu) savevm paused > > > > # restore the one running > > (qemu) info status > > VM status: paused > > (qemu) loadvm running > > (qemu) info status > > VM status: running > > > > # restore the one paused > > (qemu) loadvm paused > > (qemu) info status > > VM status: paused > > (qemu) cont > > (qemu)info status > > VM status: running > > > > > > Signed-off-by: Hu Tao <hutao@cn.fujitsu.com> > > Lack of pause state on guest images is annoying. > > Fail to see why the panic feature depends on preservation of cpu > runstate. To preserve the panic state if guest panic happens in the midway of migration. > > > include/sysemu/sysemu.h | 2 ++ > > migration.c | 6 +----- > > monitor.c | 5 ++--- > > savevm.c | 1 + > > vl.c | 34 ++++++++++++++++++++++++++++++++++ > > 5 files changed, 40 insertions(+), 8 deletions(-) > > > > diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h > > index 337ce7d..7a69fde 100644 > > --- a/include/sysemu/sysemu.h > > +++ b/include/sysemu/sysemu.h > > @@ -19,6 +19,8 @@ extern uint8_t qemu_uuid[]; > > int qemu_uuid_parse(const char *str, uint8_t *uuid); > > #define UUID_FMT "%02hhx%02hhx%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx" > > > > +void save_run_state(void); > > +void load_run_state(void); > > bool runstate_check(RunState state); > > void runstate_set(RunState new_state); > > int runstate_is_running(void); > > diff --git a/migration.c b/migration.c > > index 77c1971..f96cfd6 100644 > > --- a/migration.c > > +++ b/migration.c > > @@ -108,11 +108,7 @@ static void process_incoming_migration_co(void *opaque) > > /* Make sure all file formats flush their mutable metadata */ > > bdrv_invalidate_cache_all(); > > > > - if (autostart) { > > - vm_start(); > > - } else { > > - runstate_set(RUN_STATE_PAUSED); > > - } > > + load_run_state(); > > } > > > > static void enter_migration_coroutine(void *opaque) > > diff --git a/monitor.c b/monitor.c > > index 20bd19b..9381ed0 100644 > > --- a/monitor.c > > +++ b/monitor.c > > @@ -2059,13 +2059,12 @@ void qmp_closefd(const char *fdname, Error **errp) > > > > static void do_loadvm(Monitor *mon, const QDict *qdict) > > { > > - int saved_vm_running = runstate_is_running(); > > const char *name = qdict_get_str(qdict, "name"); > > > > vm_stop(RUN_STATE_RESTORE_VM); > > > > - if (load_vmstate(name) == 0 && saved_vm_running) { > > - vm_start(); > > + if (load_vmstate(name) == 0) { > > + load_run_state(); > > } > > } > > > > diff --git a/savevm.c b/savevm.c > > index 304d1ef..10f1d56 100644 > > --- a/savevm.c > > +++ b/savevm.c > > @@ -2112,6 +2112,7 @@ void do_savevm(Monitor *mon, const QDict *qdict) > > } > > > > saved_vm_running = runstate_is_running(); > > + save_run_state(); > > vm_stop(RUN_STATE_SAVE_VM); > > > > memset(sn, 0, sizeof(*sn)); > > diff --git a/vl.c b/vl.c > > index 4ee1302..b0bcf1e 100644 > > --- a/vl.c > > +++ b/vl.c > > @@ -520,6 +520,7 @@ static int default_driver_check(QemuOpts *opts, void *opaque) > > /* QEMU state */ > > > > static RunState current_run_state = RUN_STATE_PRELAUNCH; > > +static RunState saved_run_state = RUN_STATE_PRELAUNCH; > > > > typedef struct { > > RunState from; > > @@ -543,6 +544,7 @@ static const RunStateTransition runstate_transitions_def[] = { > > { RUN_STATE_PAUSED, RUN_STATE_FINISH_MIGRATE }, > > > > { RUN_STATE_POSTMIGRATE, RUN_STATE_RUNNING }, > > + { RUN_STATE_POSTMIGRATE, RUN_STATE_PAUSED }, > > { RUN_STATE_POSTMIGRATE, RUN_STATE_FINISH_MIGRATE }, > > > > { RUN_STATE_PRELAUNCH, RUN_STATE_RUNNING }, > > @@ -553,6 +555,7 @@ static const RunStateTransition runstate_transitions_def[] = { > > { RUN_STATE_FINISH_MIGRATE, RUN_STATE_POSTMIGRATE }, > > > > { RUN_STATE_RESTORE_VM, RUN_STATE_RUNNING }, > > + { RUN_STATE_RESTORE_VM, RUN_STATE_PAUSED }, > > > > { RUN_STATE_RUNNING, RUN_STATE_DEBUG }, > > { RUN_STATE_RUNNING, RUN_STATE_INTERNAL_ERROR }, > > @@ -582,11 +585,39 @@ static const RunStateTransition runstate_transitions_def[] = { > > > > static bool runstate_valid_transitions[RUN_STATE_MAX][RUN_STATE_MAX]; > > > > +void save_run_state(void) > > +{ > > + saved_run_state = current_run_state; > > +} > > + > > +void load_run_state(void) > > +{ > > + if (saved_run_state == RUN_STATE_RUNNING) { > > + vm_start(); > > + } else if (!runstate_check(saved_run_state)) { > > + runstate_set(saved_run_state); > > + } else { > > + ; /* leave unchanged */ > > + } > > +} > > + > > bool runstate_check(RunState state) > > { > > return current_run_state == state; > > } > > > > +static void runstate_save(QEMUFile *f, void *opaque) > > +{ > > + qemu_put_byte(f, saved_run_state); > > +} > > + > > +static int runstate_load(QEMUFile *f, void *opaque, int version_id) > > +{ > > + saved_run_state = qemu_get_byte(f); > > + > > + return 0; > > +} > > This breaks loading images without support for runstate information. > Is it possible to overcome this limitation? It's successful to load images without support for runstate information, but trying to set run state to RUN_STATE_PRELAUNCH(the default value of saved_run_state), which is invalid. The problem can be solved by setting the default value of saved_run_state to RUN_STATE_RUNNING. > > Would be happier if this patch could be debated on QEMU list.
diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h index 337ce7d..7a69fde 100644 --- a/include/sysemu/sysemu.h +++ b/include/sysemu/sysemu.h @@ -19,6 +19,8 @@ extern uint8_t qemu_uuid[]; int qemu_uuid_parse(const char *str, uint8_t *uuid); #define UUID_FMT "%02hhx%02hhx%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx" +void save_run_state(void); +void load_run_state(void); bool runstate_check(RunState state); void runstate_set(RunState new_state); int runstate_is_running(void); diff --git a/migration.c b/migration.c index 77c1971..f96cfd6 100644 --- a/migration.c +++ b/migration.c @@ -108,11 +108,7 @@ static void process_incoming_migration_co(void *opaque) /* Make sure all file formats flush their mutable metadata */ bdrv_invalidate_cache_all(); - if (autostart) { - vm_start(); - } else { - runstate_set(RUN_STATE_PAUSED); - } + load_run_state(); } static void enter_migration_coroutine(void *opaque) diff --git a/monitor.c b/monitor.c index 20bd19b..9381ed0 100644 --- a/monitor.c +++ b/monitor.c @@ -2059,13 +2059,12 @@ void qmp_closefd(const char *fdname, Error **errp) static void do_loadvm(Monitor *mon, const QDict *qdict) { - int saved_vm_running = runstate_is_running(); const char *name = qdict_get_str(qdict, "name"); vm_stop(RUN_STATE_RESTORE_VM); - if (load_vmstate(name) == 0 && saved_vm_running) { - vm_start(); + if (load_vmstate(name) == 0) { + load_run_state(); } } diff --git a/savevm.c b/savevm.c index 304d1ef..10f1d56 100644 --- a/savevm.c +++ b/savevm.c @@ -2112,6 +2112,7 @@ void do_savevm(Monitor *mon, const QDict *qdict) } saved_vm_running = runstate_is_running(); + save_run_state(); vm_stop(RUN_STATE_SAVE_VM); memset(sn, 0, sizeof(*sn)); diff --git a/vl.c b/vl.c index 4ee1302..b0bcf1e 100644 --- a/vl.c +++ b/vl.c @@ -520,6 +520,7 @@ static int default_driver_check(QemuOpts *opts, void *opaque) /* QEMU state */ static RunState current_run_state = RUN_STATE_PRELAUNCH; +static RunState saved_run_state = RUN_STATE_PRELAUNCH; typedef struct { RunState from; @@ -543,6 +544,7 @@ static const RunStateTransition runstate_transitions_def[] = { { RUN_STATE_PAUSED, RUN_STATE_FINISH_MIGRATE }, { RUN_STATE_POSTMIGRATE, RUN_STATE_RUNNING }, + { RUN_STATE_POSTMIGRATE, RUN_STATE_PAUSED }, { RUN_STATE_POSTMIGRATE, RUN_STATE_FINISH_MIGRATE }, { RUN_STATE_PRELAUNCH, RUN_STATE_RUNNING }, @@ -553,6 +555,7 @@ static const RunStateTransition runstate_transitions_def[] = { { RUN_STATE_FINISH_MIGRATE, RUN_STATE_POSTMIGRATE }, { RUN_STATE_RESTORE_VM, RUN_STATE_RUNNING }, + { RUN_STATE_RESTORE_VM, RUN_STATE_PAUSED }, { RUN_STATE_RUNNING, RUN_STATE_DEBUG }, { RUN_STATE_RUNNING, RUN_STATE_INTERNAL_ERROR }, @@ -582,11 +585,39 @@ static const RunStateTransition runstate_transitions_def[] = { static bool runstate_valid_transitions[RUN_STATE_MAX][RUN_STATE_MAX]; +void save_run_state(void) +{ + saved_run_state = current_run_state; +} + +void load_run_state(void) +{ + if (saved_run_state == RUN_STATE_RUNNING) { + vm_start(); + } else if (!runstate_check(saved_run_state)) { + runstate_set(saved_run_state); + } else { + ; /* leave unchanged */ + } +} + bool runstate_check(RunState state) { return current_run_state == state; } +static void runstate_save(QEMUFile *f, void *opaque) +{ + qemu_put_byte(f, saved_run_state); +} + +static int runstate_load(QEMUFile *f, void *opaque, int version_id) +{ + saved_run_state = qemu_get_byte(f); + + return 0; +} + static void runstate_init(void) { const RunStateTransition *p; @@ -596,6 +627,9 @@ static void runstate_init(void) for (p = &runstate_transitions_def[0]; p->from != RUN_STATE_MAX; p++) { runstate_valid_transitions[p->from][p->to] = true; } + + register_savevm(NULL, "runstate", 0, 1, + runstate_save, runstate_load, NULL); } /* This function will abort() on invalid state transitions */
This patch enables preservation of cpu runstate during save/load vm. So when a vm is restored from snapshot, the cpu runstate is restored, too. See following example: # save two vms: one is running, the other is paused (qemu) info status VM status: running (qemu) savevm running (qemu) stop (qemu) info status VM status: paused (qemu) savevm paused # restore the one running (qemu) info status VM status: paused (qemu) loadvm running (qemu) info status VM status: running # restore the one paused (qemu) loadvm paused (qemu) info status VM status: paused (qemu) cont (qemu)info status VM status: running Signed-off-by: Hu Tao <hutao@cn.fujitsu.com> --- include/sysemu/sysemu.h | 2 ++ migration.c | 6 +----- monitor.c | 5 ++--- savevm.c | 1 + vl.c | 34 ++++++++++++++++++++++++++++++++++ 5 files changed, 40 insertions(+), 8 deletions(-)