hashmap: introduce hash_ops to make struct Hashmap smaller

It is redundant to store 'hash' and 'compare' function pointers in
struct Hashmap separately. The functions always comprise a pair.
Store a single pointer to struct hash_ops instead.

systemd keeps hundreds of hashmaps, so this saves a little bit of
memory.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/core/mount-setup.c b/src/core/mount-setup.c
index cc2633e3b..23a66d2e9 100644
--- a/src/core/mount-setup.c
+++ b/src/core/mount-setup.c
@@ -235,7 +235,7 @@ int mount_cgroup_controllers(char ***join_controllers) {
                 return 0;
         }
 
-        controllers = set_new(string_hash_func, string_compare_func);
+        controllers = set_new(&string_hash_ops);
         if (!controllers)
                 return log_oom();