@@ -107,7 +107,9 @@ typedef struct {
/* array of pages to sent.
* The owner of 'pages' depends of 'pending_job' value:
* pending_job == 0 -> migration_thread can use it.
+ * No need for mutex lock.
* pending_job != 0 -> multifd_channel can use it.
+ * No need for mutex lock.
*/
MultiFDPages_t *pages;
@@ -632,6 +632,8 @@ static void *multifd_send_thread(void *opaque)
p->flags |= MULTIFD_FLAG_SYNC;
p->sync_needed = false;
}
+ qemu_mutex_unlock(&p->mutex);
+
p->iovs_num = 1;
p->normal_num = 0;
@@ -648,11 +650,6 @@ static void *multifd_send_thread(void *opaque)
}
}
multifd_send_fill_packet(p);
- p->num_packets++;
- p->total_normal_pages += p->normal_num;
- p->pages->num = 0;
- p->pages->block = NULL;
- qemu_mutex_unlock(&p->mutex);
trace_multifd_send(p->id, packet_num, p->normal_num, p->flags,
p->next_packet_size);
@@ -667,6 +664,10 @@ static void *multifd_send_thread(void *opaque)
}
qemu_mutex_lock(&p->mutex);
+ p->num_packets++;
+ p->total_normal_pages += p->normal_num;
+ p->pages->num = 0;
+ p->pages->block = NULL;
p->sent_bytes += p->packet_len;;
p->sent_bytes += p->next_packet_size;
p->pending_job--;
We do the send_prepare() and the fill of the head packet without the mutex held. It will help a lot for compression and later in the series for zero pages. Notice that we can use p->pages without holding p->mutex because p->pending_job == 1. Signed-off-by: Juan Quintela <quintela@redhat.com> --- migration/multifd.h | 2 ++ migration/multifd.c | 11 ++++++----- 2 files changed, 8 insertions(+), 5 deletions(-)