tests: avoid rare FP failure in new du test

* tests/du/move-dir-while-traversing: Create an even larger tree
to avoid a false-positive failure due to du terminating before
the rename is triggered.

diff --git a/tests/du/move-dir-while-traversing b/tests/du/move-dir-while-traversing
index 9605831..c711e02 100755 (executable)
--- a/tests/du/move-dir-while-traversing
+++ b/tests/du/move-dir-while-traversing
@@ -63,9 +63,11 @@ mkdir d2 || framework_failure
 long=d/e/f/g/h/i/j/k/l/m/n/o/p/q/r/s/t/u/v/w/x/y/z
 # One iteration of this loop creates a tree with which
 # du sometimes completes its traversal before the above rename.
-# Even 5 iterations was not enough in 2 of 7 "make -j20 check" runs on a
+# Five iterations was not enough in 2 of 7 "make -j20 check" runs on a
 # 6/12-core system.  However, using "10", I saw no failure in 20 trials.
-for i in $(seq 10); do
+# Using 10 iterations was not enough, either.
+# Using 30, I saw no failure in 200 trials.
+for i in $(seq 30); do
   mkdir -p $t/3/a/b/c/$i/$long || framework_failure
 done
 timeout 6 ./inotify-watch-for-dir-access.py $t/3/a/b > start-msg &