On Sun, Nov 05, 2023 at 07:54:16PM +0000, Al Viro wrote: > * have shrink_dcache_for_umount() mark the superblock (either in > ->s_flags or inside the ->s_dentry_lru itself) and have the logics > in retain_dentry() that does insertion into LRU list check ->d_sb for that > mark, treating its presence as "do not retain". BTW, no barriers, etc. are needed for those - once we are into shrink_dentry_for_umount() there must be no dput() calls anywhere on that filesystem.
