Add a comment explaining that every other entry in the list is unmapped to intentionally create fragmentation with locked pages before invoking check_compaction(). Fixes: bd67d5c15cc1 ("Test compaction of mlocked memory") Signed-off-by: Sayali Patil --- tools/testing/selftests/mm/compaction_test.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/tools/testing/selftests/mm/compaction_test.c b/tools/testing/selftests/mm/compaction_test.c index 30209c40b697..e1610e2fbdf6 100644 --- a/tools/testing/selftests/mm/compaction_test.c +++ b/tools/testing/selftests/mm/compaction_test.c @@ -261,6 +261,9 @@ int main(int argc, char **argv) mem_fragmentable_MB -= MAP_SIZE_MB; } + /* Unmap every other entry in the list to create fragmentation with + * locked pages before invoking check_compaction(). + */ for (entry = list; entry != NULL; entry = entry->next) { munmap(entry->map, MAP_SIZE); if (!entry->next) -- 2.52.0