commit 1d58872a910cdfe8df79be5ffb4c4c6c13768f40
author Xiao Guangrong <xiaoguangrong@tencent.com> Tue Aug 21 16:10:20 2018 +0800
committer Juan Quintela <quintela@redhat.com> Wed Aug 22 12:34:11 2018 +0200
tree e9512fe2fb45ad8555dcda61f2ee40314889e790
parent 923709896b1b01fb982c93492ad01b233e6b6023

migration: do not wait for free thread

Instead of putting the main thread to sleep state to wait for
free compression thread, we can directly post it out as normal
page that reduces the latency and uses CPUs more efficiently

A parameter, compress-wait-thread, is introduced, it can be
enabled if the user really wants the old behavior

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>

hmp.c

diff --git a/hmp.c b/hmp.c
index c38e8b1..9147037 100644
--- a/hmp.c
+++ b/hmp.c
@@ -327,6 +327,10 @@
         monitor_printf(mon, "%s: %u\n",
             MigrationParameter_str(MIGRATION_PARAMETER_COMPRESS_THREADS),
             params->compress_threads);
+        assert(params->has_compress_wait_thread);
+        monitor_printf(mon, "%s: %s\n",
+            MigrationParameter_str(MIGRATION_PARAMETER_COMPRESS_WAIT_THREAD),
+            params->compress_wait_thread ? "on" : "off");
         assert(params->has_decompress_threads);
         monitor_printf(mon, "%s: %u\n",
             MigrationParameter_str(MIGRATION_PARAMETER_DECOMPRESS_THREADS),
@@ -1627,6 +1631,10 @@
         p->has_compress_threads = true;
         visit_type_int(v, param, &p->compress_threads, &err);
         break;
+    case MIGRATION_PARAMETER_COMPRESS_WAIT_THREAD:
+        p->has_compress_wait_thread = true;
+        visit_type_bool(v, param, &p->compress_wait_thread, &err);
+        break;
     case MIGRATION_PARAMETER_DECOMPRESS_THREADS:
         p->has_decompress_threads = true;
         visit_type_int(v, param, &p->decompress_threads, &err);