LU-9771 flr: randomize mirror pick

[fs/lustre-release.git] / lustre / lov / lov_object.c

diff --git a/lustre/lov/lov_object.c b/lustre/lov/lov_object.c
index 15d5c3c..94b98af 100644 (file)
--- a/lustre/lov/lov_object.c
+++ b/lustre/lov/lov_object.c
@@ -776,6 +776,25 @@ static int lov_init_composite(const struct lu_env *env, struct lov_device *dev,
                GOTO(out, result = -EINVAL);
        }
 
+       if (OBD_FAIL_CHECK(OBD_FAIL_FLR_RANDOM_PICK_MIRROR)) {
+               unsigned int seq;
+
+               get_random_bytes(&seq, sizeof(seq));
+               seq %= mirror_count;
+
+               i = 0;
+               lov_foreach_mirror_entry(lov, lre) {
+                       i++;
+                       if (lre->lre_stale)
+                               continue;
+
+                       if (!seq--) {
+                               comp->lo_preferred_mirror = i - 1;
+                               break;
+                       }
+               }
+       }
+
        LASSERT(comp->lo_preferred_mirror >= 0);
 
        EXIT;