vnc: recycle empty vs->output buffer
If the vs->output buffer is empty it will be dropped
by the next qio_buffer_move_empty in vnc_jobs_consume_buffer
anyway. So reuse the allocated buffer from this buffer
in the worker thread where we otherwise would start with
an empty (unallocated buffer).
Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 1446203414-4013-17-git-send-email-kraxel@redhat.com
[ added a comment describing the non-obvious optimization ]
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
diff --git a/ui/vnc-jobs.c b/ui/vnc-jobs.c
index 12389cc..08f0163 100644
--- a/ui/vnc-jobs.c
+++ b/ui/vnc-jobs.c
@@ -235,6 +235,14 @@
vnc_unlock_output(job->vs);
goto disconnected;
}
+ if (buffer_empty(&job->vs->output)) {
+ /*
+ * Looks like a NOP as it obviously moves no data. But it
+ * moves the empty buffer, so we don't have to malloc a new
+ * one for vs.output
+ */
+ buffer_move_empty(&vs.output, &job->vs->output);
+ }
vnc_unlock_output(job->vs);
/* Make a local copy of vs and switch output buffers */
