resctrl: Set MBA defaults properly

Similarly to CAT, when you set some values in an group, remove the group and
recreate it, the previous values will be kept there.  In order to not get values
from a previous setting (a previous VM, for example), we need to set them to
sensible defaults.  The same way we do that for CAT, just set the same values as
the default group has.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

src/util/virresctrl.c

@@ -2143,6 +2143,42 @@ virResctrlAllocMemoryBandwidth(virResctrlInfoPtr resctrl,
 }
 
 
+static int
+virResctrlAllocCopyMemBW(virResctrlAllocPtr dst,
+                         virResctrlAllocPtr src)
+{
+    size_t i = 0;
+    virResctrlAllocMemBWPtr dst_bw = NULL;
+    virResctrlAllocMemBWPtr src_bw = src->mem_bw;
+
+    if (!src->mem_bw)
+        return 0;
+
+    if (!dst->mem_bw &&
+        VIR_ALLOC(dst->mem_bw) < 0)
+        return -1;
+
+    dst_bw = dst->mem_bw;
+
+    if (src_bw->nbandwidths > dst_bw->nbandwidths &&
+        VIR_EXPAND_N(dst_bw->bandwidths, dst_bw->nbandwidths,
+                     src_bw->nbandwidths - dst_bw->nbandwidths) < 0)
+        return -1;
+
+    for (i = 0; i < src_bw->nbandwidths; i++) {
+        if (dst_bw->bandwidths[i]) {
+            *dst_bw->bandwidths[i] = 123;
+            continue;
+        }
+        if (VIR_ALLOC(dst_bw->bandwidths[i]) < 0)
+            return -1;
+        *dst_bw->bandwidths[i] = *src_bw->bandwidths[i];
+    }
+
+    return 0;
+}
+
+
 static int
 virResctrlAllocCopyMasks(virResctrlAllocPtr dst,
                          virResctrlAllocPtr src)
@@ -2210,6 +2246,9 @@ virResctrlAllocAssign(virResctrlInfoPtr resctrl,
     if (virResctrlAllocCopyMasks(alloc, alloc_default) < 0)
         goto cleanup;
 
+    if (virResctrlAllocCopyMemBW(alloc, alloc_default) < 0)
+        goto cleanup;
+
     for (level = 0; level < alloc->nlevels; level++) {
         virResctrlAllocPerLevelPtr a_level = alloc->levels[level];
         virResctrlAllocPerLevelPtr f_level = NULL;