Message ID | 20110107183518.13483.52633.stgit@s20.home |
---|---|
State | New |
Headers | show |
Am 07.01.2011 19:39, Alex Williamson wrote: > The no_migrate save state flag is currently only checked in the > last phase of migration. This means that we potentially waste > a lot of time and bandwidth with the live state handlers before > we ever check the no_migrate flags. The error message printed > when we catch a non-migratable device doesn't get printed for > a detached migration. And, no_migrate does nothing to prevent > an incoming migration to a target that includes a non-migratable > device. This attempts to fix all of these. > > One notable difference in behavior is that an outgoing migration > now checks for non-migratable devices before ever connecting to > the target system. This means the target will remain listening > rather than exit from failure. > > Signed-off-by: Alex Williamson <alex.williamson@redhat.com> > --- > > Daniel, adding you to see if libvirt cares about the difference in > whether the target exits on migration failure as noted above. > > Also adding Michael as he's complained about the no_migrate check > happening so late in the process. > > migration.c | 4 ++++ > savevm.c | 39 +++++++++++++++++++++++++-------------- > sysemu.h | 1 + > 3 files changed, 30 insertions(+), 14 deletions(-) > > diff --git a/migration.c b/migration.c > index e5ba51c..d593b1d 100644 > --- a/migration.c > +++ b/migration.c > @@ -88,6 +88,10 @@ int do_migrate(Monitor *mon, const QDict *qdict, QObject **ret_data) > return -1; > } > > + if (qemu_savevm_state_blocked(mon)) { > + return -1; > + } > + > if (strstart(uri, "tcp:", &p)) { > s = tcp_start_outgoing_migration(mon, p, max_throttle, detach, > blk, inc); > diff --git a/savevm.c b/savevm.c > index 90aa237..6675c33 100644 > --- a/savevm.c > +++ b/savevm.c > @@ -1401,19 +1401,13 @@ static int vmstate_load(QEMUFile *f, SaveStateEntry *se, int version_id) > return vmstate_load_state(f, se->vmsd, se->opaque, version_id); > } > > -static int vmstate_save(QEMUFile *f, SaveStateEntry *se) > +static void vmstate_save(QEMUFile *f, SaveStateEntry *se) > { > - if (se->no_migrate) { > - return -1; > - } > - > if (!se->vmsd) { /* Old style */ > se->save_state(f, se->opaque); > - return 0; > + return; > } > vmstate_save_state(f,se->vmsd, se->opaque); > - > - return 0; > } > > #define QEMU_VM_FILE_MAGIC 0x5145564d > @@ -1427,6 +1421,20 @@ static int vmstate_save(QEMUFile *f, SaveStateEntry *se) > #define QEMU_VM_SECTION_FULL 0x04 > #define QEMU_VM_SUBSECTION 0x05 > > +int qemu_savevm_state_blocked(Monitor *mon) > +{ > + SaveStateEntry *se; > + > + QTAILQ_FOREACH(se, &savevm_handlers, entry) { > + if (se->no_migrate) { > + monitor_printf(mon, "state blocked by non-migratable device '%s'\n", > + se->idstr); > + return -EINVAL; > + } > + } > + return 0; > +} > + > int qemu_savevm_state_begin(Monitor *mon, QEMUFile *f, int blk_enable, > int shared) > { > @@ -1508,7 +1516,6 @@ int qemu_savevm_state_iterate(Monitor *mon, QEMUFile *f) > int qemu_savevm_state_complete(Monitor *mon, QEMUFile *f) > { > SaveStateEntry *se; > - int r; > > cpu_synchronize_all_states(); > > @@ -1541,11 +1548,7 @@ int qemu_savevm_state_complete(Monitor *mon, QEMUFile *f) > qemu_put_be32(f, se->instance_id); > qemu_put_be32(f, se->version_id); > > - r = vmstate_save(f, se); > - if (r < 0) { > - monitor_printf(mon, "cannot migrate with device '%s'\n", se->idstr); > - return r; > - } > + vmstate_save(f, se); > } > > qemu_put_byte(f, QEMU_VM_EOF); > @@ -1575,6 +1578,10 @@ static int qemu_savevm_state(Monitor *mon, QEMUFile *f) > saved_vm_running = vm_running; > vm_stop(0); > > + ret = qemu_savevm_state_blocked(mon); > + if (ret < 0) > + goto out; > + { } :) (Is there really no one bored out there and wants to write a check-patch script?) > ret = qemu_savevm_state_begin(mon, f, 0, 0); > if (ret < 0) > goto out; > @@ -1692,6 +1699,10 @@ int qemu_loadvm_state(QEMUFile *f) > unsigned int v; > int ret; > > + if (qemu_savevm_state_blocked(default_mon)) { > + return -EINVAL; > + } > + > v = qemu_get_be32(f); > if (v != QEMU_VM_FILE_MAGIC) > return -EINVAL; > diff --git a/sysemu.h b/sysemu.h > index e728ea1..eefaba5 100644 > --- a/sysemu.h > +++ b/sysemu.h > @@ -75,6 +75,7 @@ void qemu_announce_self(void); > > void main_loop_wait(int nonblocking); > > +int qemu_savevm_state_blocked(Monitor *mon); > int qemu_savevm_state_begin(Monitor *mon, QEMUFile *f, int blk_enable, > int shared); > int qemu_savevm_state_iterate(Monitor *mon, QEMUFile *f); > Much nicer! Jan
On Fri, Jan 07, 2011 at 07:47:34PM +0100, Jan Kiszka wrote: > (Is there really no one bored out there and wants to write a check-patch > script?) Might be better to use an existing tool: http://www.kernel.org/pub/linux/kernel/people/apw/checkpatch/
On Sun, Jan 9, 2011 at 9:57 AM, Michael S. Tsirkin <mst@redhat.com> wrote: > On Fri, Jan 07, 2011 at 07:47:34PM +0100, Jan Kiszka wrote: >> (Is there really no one bored out there and wants to write a check-patch >> script?) > > Might be better to use an existing tool: > http://www.kernel.org/pub/linux/kernel/people/apw/checkpatch/ Thanks for the link, I had previously tried to use something else. I'll send patches to add checkpatch.pl for QEMU.
diff --git a/migration.c b/migration.c index e5ba51c..d593b1d 100644 --- a/migration.c +++ b/migration.c @@ -88,6 +88,10 @@ int do_migrate(Monitor *mon, const QDict *qdict, QObject **ret_data) return -1; } + if (qemu_savevm_state_blocked(mon)) { + return -1; + } + if (strstart(uri, "tcp:", &p)) { s = tcp_start_outgoing_migration(mon, p, max_throttle, detach, blk, inc); diff --git a/savevm.c b/savevm.c index 90aa237..6675c33 100644 --- a/savevm.c +++ b/savevm.c @@ -1401,19 +1401,13 @@ static int vmstate_load(QEMUFile *f, SaveStateEntry *se, int version_id) return vmstate_load_state(f, se->vmsd, se->opaque, version_id); } -static int vmstate_save(QEMUFile *f, SaveStateEntry *se) +static void vmstate_save(QEMUFile *f, SaveStateEntry *se) { - if (se->no_migrate) { - return -1; - } - if (!se->vmsd) { /* Old style */ se->save_state(f, se->opaque); - return 0; + return; } vmstate_save_state(f,se->vmsd, se->opaque); - - return 0; } #define QEMU_VM_FILE_MAGIC 0x5145564d @@ -1427,6 +1421,20 @@ static int vmstate_save(QEMUFile *f, SaveStateEntry *se) #define QEMU_VM_SECTION_FULL 0x04 #define QEMU_VM_SUBSECTION 0x05 +int qemu_savevm_state_blocked(Monitor *mon) +{ + SaveStateEntry *se; + + QTAILQ_FOREACH(se, &savevm_handlers, entry) { + if (se->no_migrate) { + monitor_printf(mon, "state blocked by non-migratable device '%s'\n", + se->idstr); + return -EINVAL; + } + } + return 0; +} + int qemu_savevm_state_begin(Monitor *mon, QEMUFile *f, int blk_enable, int shared) { @@ -1508,7 +1516,6 @@ int qemu_savevm_state_iterate(Monitor *mon, QEMUFile *f) int qemu_savevm_state_complete(Monitor *mon, QEMUFile *f) { SaveStateEntry *se; - int r; cpu_synchronize_all_states(); @@ -1541,11 +1548,7 @@ int qemu_savevm_state_complete(Monitor *mon, QEMUFile *f) qemu_put_be32(f, se->instance_id); qemu_put_be32(f, se->version_id); - r = vmstate_save(f, se); - if (r < 0) { - monitor_printf(mon, "cannot migrate with device '%s'\n", se->idstr); - return r; - } + vmstate_save(f, se); } qemu_put_byte(f, QEMU_VM_EOF); @@ -1575,6 +1578,10 @@ static int qemu_savevm_state(Monitor *mon, QEMUFile *f) saved_vm_running = vm_running; vm_stop(0); + ret = qemu_savevm_state_blocked(mon); + if (ret < 0) + goto out; + ret = qemu_savevm_state_begin(mon, f, 0, 0); if (ret < 0) goto out; @@ -1692,6 +1699,10 @@ int qemu_loadvm_state(QEMUFile *f) unsigned int v; int ret; + if (qemu_savevm_state_blocked(default_mon)) { + return -EINVAL; + } + v = qemu_get_be32(f); if (v != QEMU_VM_FILE_MAGIC) return -EINVAL; diff --git a/sysemu.h b/sysemu.h index e728ea1..eefaba5 100644 --- a/sysemu.h +++ b/sysemu.h @@ -75,6 +75,7 @@ void qemu_announce_self(void); void main_loop_wait(int nonblocking); +int qemu_savevm_state_blocked(Monitor *mon); int qemu_savevm_state_begin(Monitor *mon, QEMUFile *f, int blk_enable, int shared); int qemu_savevm_state_iterate(Monitor *mon, QEMUFile *f);
The no_migrate save state flag is currently only checked in the last phase of migration. This means that we potentially waste a lot of time and bandwidth with the live state handlers before we ever check the no_migrate flags. The error message printed when we catch a non-migratable device doesn't get printed for a detached migration. And, no_migrate does nothing to prevent an incoming migration to a target that includes a non-migratable device. This attempts to fix all of these. One notable difference in behavior is that an outgoing migration now checks for non-migratable devices before ever connecting to the target system. This means the target will remain listening rather than exit from failure. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> --- Daniel, adding you to see if libvirt cares about the difference in whether the target exits on migration failure as noted above. Also adding Michael as he's complained about the no_migrate check happening so late in the process. migration.c | 4 ++++ savevm.c | 39 +++++++++++++++++++++++++-------------- sysemu.h | 1 + 3 files changed, 30 insertions(+), 14 deletions(-)