CA-150812: Xentop doesn't display VBD3 data

Modified metrics struct to keep a version control for the vbd3 metrics. This is
required by xentop to check the correctness of the metrics file.

Signed-off-by: Jorge Martin <[email protected]>

Author: martinjorge

drivers/tapdisk-metrics.c

@@ -216,6 +216,7 @@ td_metrics_vbd_start(int domain, int id, stats_t *vbd_stats)
         goto out;
    }
     vbd_stats->stats = vbd_stats->shm.mem;
+    vbd_stats->stats->version = 1;
 out:
     return err;
 

drivers/tapdisk-metrics.h

@@ -21,7 +21,7 @@
 
 #define TAPDISK_METRICS_PATHF        "/dev/shm/td3-%d"
 #define TAPDISK_METRICS_VDI_PATHF    "%s/vdi-%hu"
-#define TAPDISK_METRICS_VBD_PATHF    "%s/vbd-%d-%d"
+#define TAPDISK_METRICS_VBD_PATHF    "%s/vbd3-%d-%d"
 #define TAPDISK_METRICS_BLKTAP_PATHF "%s/blktap-%d"
 #define TAPDISK_METRICS_NBD_PATHF "%s/nbd-%d"
 
@@ -31,6 +31,7 @@
 #include "tapdisk.h"
 
 struct stats {
+    uint32_t version; //Used to check version of this struct in xentop.
     unsigned long long read_reqs_submitted;
     unsigned long long read_reqs_completed;
     unsigned long long read_sectors;