rgw/rados: fix list_objects_ordered() detection of "forward progress"

for multiple versions of the same object name, ListObjectVersions is
supposed to return versions "in the order that they were stored,
returning the most recently stored object first"

this sort order is preserved by the bucket index in cls_rgw, so
list_objects_ordered() should not expect the version ids to be sorted
lexicographically. replace the not-less-than comparison with equality

Signed-off-by: Casey Bodley <[email protected]>

Author: cbodley

src/rgw/driver/rados/rgw_rados.cc

@@ -1862,7 +1862,7 @@ int RGWRados::Bucket::List::list_objects_ordered(
     ldpp_dout(dpp, 20) << __func__ <<
       ": starting attempt " << attempt << dendl;
 
-    if (attempt > 1 && !(prev_marker < cur_marker)) {
+    if (attempt > 1 && prev_marker == cur_marker) {
       // we've failed to make forward progress
       ldpp_dout(dpp, 0) << "ERROR: " << __func__ <<
 	" marker failed to make forward progress; attempt=" << attempt <<