Re: [Qemu-devel] [PATCH 09/36] migration: don't write when migration is not active

2011-10-17 Thread Anthony Liguori 

On 10/11/2011 05:00 AM, Juan Quintela wrote:

If migration is not active, just ignore writes.

Signed-off-by: Juan Quintelaquint...@redhat.com
---
  migration.c |4 
  1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/migration.c b/migration.c
index 7ac1fc2..090c925 100644
--- a/migration.c
+++ b/migration.c
@@ -323,6 +323,10 @@ ssize_t migrate_fd_put_buffer(void *opaque, const void 
*data, size_t size)
  FdMigrationState *s = opaque;
  ssize_t ret;

+if (s-state != MIG_STATE_ACTIVE) {
+return -EIO;
+}
+


Buffered file is buffered.  The migration may complete before the buffer is 
completely drained.  That means additional put_buffer calls may come after the 
migration state has moved to complete.


Regards,

Anthony Liguori


  do {
  ret = s-write(s, data, size);
  } while (ret == -1  ((s-get_error(s)) == EINTR));

Re: [Qemu-devel] [PATCH 09/36] migration: don't write when migration is not active

2011-10-17 Thread Juan Quintela 
Anthony Liguori anth...@codemonkey.ws wrote:
 On 10/11/2011 05:00 AM, Juan Quintela wrote:
 If migration is not active, just ignore writes.

 Signed-off-by: Juan Quintelaquint...@redhat.com
 ---
   migration.c |4 
   1 files changed, 4 insertions(+), 0 deletions(-)

 diff --git a/migration.c b/migration.c
 index 7ac1fc2..090c925 100644
 --- a/migration.c
 +++ b/migration.c
 @@ -323,6 +323,10 @@ ssize_t migrate_fd_put_buffer(void *opaque, const void 
 *data, size_t size)
   FdMigrationState *s = opaque;
   ssize_t ret;

 +if (s-state != MIG_STATE_ACTIVE) {
 +return -EIO;
 +}
 +

 Buffered file is buffered.  The migration may complete before the
 buffer is completely drained.  That means additional put_buffer calls
 may come after the migration state has moved to complete.

static void migrate_fd_completed(MigrationState *s)
{
DPRINTF(setting completed state\n);
if (migrate_fd_cleanup(s)  0) {
s-state = MIG_STATE_ERROR;
} else {
s-state = MIG_STATE_COMPLETED;
runstate_set(RUN_STATE_POSTMIGRATE);
}
notifier_list_notify(migration_state_notifiers, s);
}

After all the changes in this thread, that is the only place that can
change s-state to MIG_STATE_COMPLETED, as you can see, we do that
after doing a migrate_fd_cleanup(), and that just flush + close the fd.

So, I still think that everything is done as expected. (testing confirms
that both migrate_cancel after one error don't hang and migration
without errors ends as expected.

Later, Juan.

 Regards,
 Anthony Liguori

   do {
   ret = s-write(s, data, size);
   } while (ret == -1  ((s-get_error(s)) == EINTR));

[Qemu-devel] [PATCH 09/36] migration: don't write when migration is not active

2011-10-11 Thread Juan Quintela 
If migration is not active, just ignore writes.

Signed-off-by: Juan Quintela quint...@redhat.com
---
 migration.c |4 
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/migration.c b/migration.c
index 7ac1fc2..090c925 100644
--- a/migration.c
+++ b/migration.c
@@ -323,6 +323,10 @@ ssize_t migrate_fd_put_buffer(void *opaque, const void 
*data, size_t size)
 FdMigrationState *s = opaque;
 ssize_t ret;

+if (s-state != MIG_STATE_ACTIVE) {
+return -EIO;
+}
+
 do {
 ret = s-write(s, data, size);
 } while (ret == -1  ((s-get_error(s)) == EINTR));
-- 
1.7.6.4