@@ -109,7 +109,9 @@ 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;
@@ -672,6 +672,8 @@ static void *multifd_send_thread(void *opaque)
p->flags |= MULTIFD_FLAG_SYNC;
p->sync_needed = false;
}
+ qemu_mutex_unlock(&p->mutex);
+
p->normal_num = 0;
if (use_zero_copy_send) {
@@ -688,16 +690,10 @@ static void *multifd_send_thread(void *opaque)
if (p->normal_num) {
ret = multifd_send_state->ops->send_prepare(p, &local_err);
if (ret != 0) {
- qemu_mutex_unlock(&p->mutex);
break;
}
}
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);
@@ -722,6 +718,10 @@ 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 | 12 ++++++------ 2 files changed, 8 insertions(+), 6 deletions(-)