proc: smaller RCU section in ->getattr()

struct kstat is thread local.

Link: http://lkml.kernel.org/r/20180423213626.GB9043@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 3954f50..97af285 100644 (file)
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1755,9 +1755,9 @@ int pid_getattr(const struct path *path, struct kstat *stat,
 
        generic_fillattr(inode, stat);
 
-       rcu_read_lock();
        stat->uid = GLOBAL_ROOT_UID;
        stat->gid = GLOBAL_ROOT_GID;
+       rcu_read_lock();
        task = pid_task(proc_pid(inode), PIDTYPE_PID);
        if (task) {
                if (!has_pid_permissions(pid, task, HIDEPID_INVISIBLE)) {