migration/dirtyrate: add DirtyRateStatus to denote calculation status

add DirtyRateStatus to denote calculating status.

Signed-off-by: Chuan Zheng <zhengchuan@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Li Qiang <liq3ea@gmail.com>
Message-Id: <1600237327-33618-3-git-send-email-zhengchuan@huawei.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  atomic name fixup

1 files changed, 26 insertions, 0 deletions

diff --git a/migration/dirtyrate.c b/migration/dirtyrate.c
index bf7fd24..3edf000 100644
--- a/migration/dirtyrate.c
+++ b/migration/dirtyrate.c
@@ -22,6 +22,19 @@
 #include "migration.h"
 #include "dirtyrate.h"
 
+static int CalculatingState = DIRTY_RATE_STATUS_UNSTARTED;
+
+static int dirtyrate_set_state(int *state, int old_state, int new_state)
+{
+    assert(new_state < DIRTY_RATE_STATUS__MAX);
+    if (qatomic_cmpxchg(state, old_state, new_state) == old_state) {
+        return 0;
+    } else {
+        return -1;
+    }
+}
+
+
 static void calculate_dirtyrate(struct DirtyRateConfig config)
 {
     /* todo */
@@ -31,8 +44,21 @@ static void calculate_dirtyrate(struct DirtyRateConfig config)
 void *get_dirtyrate_thread(void *arg)
 {
     struct DirtyRateConfig config = *(struct DirtyRateConfig *)arg;
+    int ret;
+
+    ret = dirtyrate_set_state(&CalculatingState, DIRTY_RATE_STATUS_UNSTARTED,
+                              DIRTY_RATE_STATUS_MEASURING);
+    if (ret == -1) {
+        error_report("change dirtyrate state failed.");
+        return NULL;
+    }
 
     calculate_dirtyrate(config);
 
+    ret = dirtyrate_set_state(&CalculatingState, DIRTY_RATE_STATUS_MEASURING,
+                              DIRTY_RATE_STATUS_MEASURED);
+    if (ret == -1) {
+        error_report("change dirtyrate state failed.");
+    }
     return NULL;
 }