| Message ID | 20210120104411.3084801-3-berrange@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | migration: bring improved savevm/loadvm/delvm to QMP | expand |
On 1/20/21 4:44 AM, Daniel P. Berrangé wrote: > From: Philippe Mathieu-Daudé <philmd@redhat.com> > > Just for consistency, following the example documented since > commit e3fe3988d7 ("error: Document Error API usage rules"), > return a boolean value indicating an error is set or not. > > Acked-by: Pavel Dovgalyuk <pavel.dovgalyuk@ispras.ru> > Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com> > --- > include/migration/snapshot.h | 9 ++++++++- > migration/savevm.c | 16 ++++++++-------- > replay/replay-debugging.c | 2 +- > replay/replay-snapshot.c | 2 +- > 4 files changed, 18 insertions(+), 11 deletions(-) > +++ b/migration/savevm.c > @@ -2729,7 +2729,7 @@ int qemu_load_device_state(QEMUFile *f) > return 0; > } > > -int save_snapshot(const char *name, Error **errp) > +bool save_snapshot(const char *name, Error **errp) > { Missing a 'return -1' that must be changed to 'return false' (see patch 11; if not fixed here, you have a window where you are inadvertently returning true on failure).
On 1/20/21 12:46 PM, Eric Blake wrote: > On 1/20/21 4:44 AM, Daniel P. Berrangé wrote: >> From: Philippe Mathieu-Daudé <philmd@redhat.com> >> >> Just for consistency, following the example documented since >> commit e3fe3988d7 ("error: Document Error API usage rules"), >> return a boolean value indicating an error is set or not. >> >> Acked-by: Pavel Dovgalyuk <pavel.dovgalyuk@ispras.ru> >> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com> >> --- >> include/migration/snapshot.h | 9 ++++++++- >> migration/savevm.c | 16 ++++++++-------- >> replay/replay-debugging.c | 2 +- >> replay/replay-snapshot.c | 2 +- >> 4 files changed, 18 insertions(+), 11 deletions(-) > > >> +++ b/migration/savevm.c >> @@ -2729,7 +2729,7 @@ int qemu_load_device_state(QEMUFile *f) >> return 0; >> } >> >> -int save_snapshot(const char *name, Error **errp) >> +bool save_snapshot(const char *name, Error **errp) >> { > > Missing a 'return -1' that must be changed to 'return false' (see patch > 11; if not fixed here, you have a window where you are inadvertently > returning true on failure). > Correction, it was patch 6/11 that introduced the 'return -1' that then got fixed in 11/11; patch 2/11 by itself is okay.
* Daniel P. Berrangé (berrange@redhat.com) wrote: > From: Philippe Mathieu-Daudé <philmd@redhat.com> > > Just for consistency, following the example documented since > commit e3fe3988d7 ("error: Document Error API usage rules"), > return a boolean value indicating an error is set or not. > > Acked-by: Pavel Dovgalyuk <pavel.dovgalyuk@ispras.ru> > Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> > --- > include/migration/snapshot.h | 9 ++++++++- > migration/savevm.c | 16 ++++++++-------- > replay/replay-debugging.c | 2 +- > replay/replay-snapshot.c | 2 +- > 4 files changed, 18 insertions(+), 11 deletions(-) > > diff --git a/include/migration/snapshot.h b/include/migration/snapshot.h > index c85b6ec75b..0eaf1ba0b1 100644 > --- a/include/migration/snapshot.h > +++ b/include/migration/snapshot.h > @@ -15,7 +15,14 @@ > #ifndef QEMU_MIGRATION_SNAPSHOT_H > #define QEMU_MIGRATION_SNAPSHOT_H > > -int save_snapshot(const char *name, Error **errp); > +/** > + * save_snapshot: Save an internal snapshot. > + * @name: name of internal snapshot > + * @errp: pointer to error object > + * On success, return %true. > + * On failure, store an error through @errp and return %false. > + */ > +bool save_snapshot(const char *name, Error **errp); > int load_snapshot(const char *name, Error **errp); > > #endif > diff --git a/migration/savevm.c b/migration/savevm.c > index 4a7237337e..ef7963f6c9 100644 > --- a/migration/savevm.c > +++ b/migration/savevm.c > @@ -2729,7 +2729,7 @@ int qemu_load_device_state(QEMUFile *f) > return 0; > } > > -int save_snapshot(const char *name, Error **errp) > +bool save_snapshot(const char *name, Error **errp) > { > BlockDriverState *bs; > QEMUSnapshotInfo sn1, *sn = &sn1; > @@ -2742,29 +2742,29 @@ int save_snapshot(const char *name, Error **errp) > AioContext *aio_context; > > if (migration_is_blocked(errp)) { > - return ret; > + return false; > } > > if (!replay_can_snapshot()) { > error_setg(errp, "Record/replay does not allow making snapshot " > "right now. Try once more later."); > - return ret; > + return false; > } > > if (!bdrv_all_can_snapshot(errp)) { > - return ret; > + return false; > } > > /* Delete old snapshots of the same name */ > if (name) { > if (bdrv_all_delete_snapshot(name, errp) < 0) { > - return ret; > + return false; > } > } > > bs = bdrv_all_find_vmstate_bs(errp); > if (bs == NULL) { > - return ret; > + return false; > } > aio_context = bdrv_get_aio_context(bs); > > @@ -2773,7 +2773,7 @@ int save_snapshot(const char *name, Error **errp) > ret = global_state_store(); > if (ret) { > error_setg(errp, "Error saving global state"); > - return ret; > + return false; > } > vm_stop(RUN_STATE_SAVE_VM); > > @@ -2845,7 +2845,7 @@ int save_snapshot(const char *name, Error **errp) > if (saved_vm_running) { > vm_start(); > } > - return ret; > + return ret == 0; > } > > void qmp_xen_save_devices_state(const char *filename, bool has_live, bool live, > diff --git a/replay/replay-debugging.c b/replay/replay-debugging.c > index 3a9b609e62..8e0050915d 100644 > --- a/replay/replay-debugging.c > +++ b/replay/replay-debugging.c > @@ -323,7 +323,7 @@ void replay_gdb_attached(void) > */ > if (replay_mode == REPLAY_MODE_PLAY > && !replay_snapshot) { > - if (save_snapshot("start_debugging", NULL) != 0) { > + if (!save_snapshot("start_debugging", NULL)) { > /* Can't create the snapshot. Continue conventional debugging. */ > } > } > diff --git a/replay/replay-snapshot.c b/replay/replay-snapshot.c > index e26fa4c892..4f2560d156 100644 > --- a/replay/replay-snapshot.c > +++ b/replay/replay-snapshot.c > @@ -77,7 +77,7 @@ void replay_vmstate_init(void) > > if (replay_snapshot) { > if (replay_mode == REPLAY_MODE_RECORD) { > - if (save_snapshot(replay_snapshot, &err) != 0) { > + if (!save_snapshot(replay_snapshot, &err)) { > error_report_err(err); > error_report("Could not create snapshot for icount record"); > exit(1); > -- > 2.29.2 >
diff --git a/include/migration/snapshot.h b/include/migration/snapshot.h index c85b6ec75b..0eaf1ba0b1 100644 --- a/include/migration/snapshot.h +++ b/include/migration/snapshot.h @@ -15,7 +15,14 @@ #ifndef QEMU_MIGRATION_SNAPSHOT_H #define QEMU_MIGRATION_SNAPSHOT_H -int save_snapshot(const char *name, Error **errp); +/** + * save_snapshot: Save an internal snapshot. + * @name: name of internal snapshot + * @errp: pointer to error object + * On success, return %true. + * On failure, store an error through @errp and return %false. + */ +bool save_snapshot(const char *name, Error **errp); int load_snapshot(const char *name, Error **errp); #endif diff --git a/migration/savevm.c b/migration/savevm.c index 4a7237337e..ef7963f6c9 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -2729,7 +2729,7 @@ int qemu_load_device_state(QEMUFile *f) return 0; } -int save_snapshot(const char *name, Error **errp) +bool save_snapshot(const char *name, Error **errp) { BlockDriverState *bs; QEMUSnapshotInfo sn1, *sn = &sn1; @@ -2742,29 +2742,29 @@ int save_snapshot(const char *name, Error **errp) AioContext *aio_context; if (migration_is_blocked(errp)) { - return ret; + return false; } if (!replay_can_snapshot()) { error_setg(errp, "Record/replay does not allow making snapshot " "right now. Try once more later."); - return ret; + return false; } if (!bdrv_all_can_snapshot(errp)) { - return ret; + return false; } /* Delete old snapshots of the same name */ if (name) { if (bdrv_all_delete_snapshot(name, errp) < 0) { - return ret; + return false; } } bs = bdrv_all_find_vmstate_bs(errp); if (bs == NULL) { - return ret; + return false; } aio_context = bdrv_get_aio_context(bs); @@ -2773,7 +2773,7 @@ int save_snapshot(const char *name, Error **errp) ret = global_state_store(); if (ret) { error_setg(errp, "Error saving global state"); - return ret; + return false; } vm_stop(RUN_STATE_SAVE_VM); @@ -2845,7 +2845,7 @@ int save_snapshot(const char *name, Error **errp) if (saved_vm_running) { vm_start(); } - return ret; + return ret == 0; } void qmp_xen_save_devices_state(const char *filename, bool has_live, bool live, diff --git a/replay/replay-debugging.c b/replay/replay-debugging.c index 3a9b609e62..8e0050915d 100644 --- a/replay/replay-debugging.c +++ b/replay/replay-debugging.c @@ -323,7 +323,7 @@ void replay_gdb_attached(void) */ if (replay_mode == REPLAY_MODE_PLAY && !replay_snapshot) { - if (save_snapshot("start_debugging", NULL) != 0) { + if (!save_snapshot("start_debugging", NULL)) { /* Can't create the snapshot. Continue conventional debugging. */ } } diff --git a/replay/replay-snapshot.c b/replay/replay-snapshot.c index e26fa4c892..4f2560d156 100644 --- a/replay/replay-snapshot.c +++ b/replay/replay-snapshot.c @@ -77,7 +77,7 @@ void replay_vmstate_init(void) if (replay_snapshot) { if (replay_mode == REPLAY_MODE_RECORD) { - if (save_snapshot(replay_snapshot, &err) != 0) { + if (!save_snapshot(replay_snapshot, &err)) { error_report_err(err); error_report("Could not create snapshot for icount record"); exit(1);