OpenE2K/qemu-e2k
13
4
Fork 0
Code Issues 4 Pull Requests Projects 2 Releases Activity

migration/multifd: Forbid spurious wakeups

Browse Source 
Now multifd's logic is designed to have no spurious wakeup.  I still
remember a talk to Juan and he seems to agree we should drop it now, and if
my memory was right it was there because multifd used to hit that when
still debugging.

Let's drop it and see what can explode; as long as it's not reaching
soft-freeze.

Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-15-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
This commit is contained in:
Peter Xu 2024-02-02 18:28:48 +08:00
parent 25a1f87875
commit 859ebaf346
1 changed files with 3 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
migration/multifd.c
View File

@ -756,7 +756,9 @@ static void *multifd_send_thread(void *opaque)
p->next_packet_size = 0;
qatomic_set(&p->pending_job, false);
qemu_mutex_unlock(&p->mutex);
} else if (qatomic_read(&p->pending_sync)) {
} else {
/* If not a normal job, must be a sync request */
assert(qatomic_read(&p->pending_sync));
p->flags = MULTIFD_FLAG_SYNC;
multifd_send_fill_packet(p);
ret = qio_channel_write_all(p->c, (void *)p->packet,
@ -771,9 +773,6 @@ static void *multifd_send_thread(void *opaque)
qatomic_set(&p->pending_sync, false);
qemu_mutex_unlock(&p->mutex);
qemu_sem_post(&p->sem_sync);
} else {
qemu_mutex_unlock(&p->mutex);
/* sometimes there are spurious wakeups */
}
}