don't bother with call_rcu() in put_files_struct()

At that point nobody can see us anyway; everything that
looks at files_fdtable(files) is separated from the
guts of put_files_struct(files) - either since files is
current->files or because we fetched it under task_lock()
and hadn't dropped that yet, or because we'd bumped
files->count while holding task_lock()...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 5 insertions, 9 deletions

diff --git a/fs/file.c b/fs/file.c
index 0be423cadb26..533fa5d56a5f 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -447,18 +447,14 @@ void put_files_struct(struct files_struct *files)
 
         if (atomic_dec_and_test(&files->count)) {
                 close_files(files);
-                /*
-                 * Free the fd and fdset arrays if we expanded them.
-                 * If the fdtable was embedded, pass files for freeing
-                 * at the end of the RCU grace period. Otherwise,
-                 * you can free files immediately.
-                 */
+                /* not really needed, since nobody can see us */
                 rcu_read_lock();
                 fdt = files_fdtable(files);
-                if (fdt != &files->fdtab)
-                        kmem_cache_free(files_cachep, files);
-                free_fdtable(fdt);
                 rcu_read_unlock();
+                /* free the arrays if they are not embedded */
+                if (fdt != &files->fdtab)
+                        __free_fdtable(fdt);
+                kmem_cache_free(files_cachep, files);
         }
 }