Comment 12 for bug 1839521

Fix Change Details
------------------

(Compare with comment #3)

The xattr dir/child inodes are evicted/disposed
immediately on file removal, not on shrinker.

$ touch /zfs/file
           <...>-23940 [006] d... 10808.746798: p_zfs_mknode_0: (zfs_mknode+0x0/0xe00 [zfs]) flag=0x0 dzp=0xffff88011aa94400
           <...>-23940 [006] d... 10808.746925: p_zfs_znode_alloc_0: (zfs_znode_alloc+0x0/0x520 [zfs]) obj=0xa
           <...>-23940 [006] d... 10808.746938: r_zfs_znode_alloc_0: (zfs_mknode+0x8a3/0xe00 [zfs] <- zfs_znode_alloc) zpp=0xffff88011aa90880

$ setfattr -n user.debug -v 1 /zfs/file
           <...>-23941 [006] d... 10818.945733: p_zfs_mknode_0: (zfs_mknode+0x0/0xe00 [zfs]) flag=0x2 dzp=0xffff88011aa90880
           <...>-23941 [006] d... 10818.945892: p_zfs_znode_alloc_0: (zfs_znode_alloc+0x0/0x520 [zfs]) obj=0xb
           <...>-23941 [006] d... 10818.945905: r_zfs_znode_alloc_0: (zfs_mknode+0x8a3/0xe00 [zfs] <- zfs_znode_alloc) zpp=0xffff88011aa961c0
           <...>-23941 [006] d... 10818.945925: p_zfs_zget_0: (zfs_zget+0x0/0x230 [zfs]) zsb=0xffff880016f00000 obj=0xa
        setfattr-23941 [006] d... 10818.945929: r_zfs_zget_0: (zfs_zaccess+0x12b/0x220 [zfs] <- zfs_zget)
        setfattr-23941 [006] d... 10818.945933: p_zfs_zget_0: (zfs_zget+0x0/0x230 [zfs]) zsb=0xffff880016f00000 obj=0xa
        setfattr-23941 [006] d... 10818.945936: r_zfs_zget_0: (zfs_zaccess+0x12b/0x220 [zfs] <- zfs_zget)
        setfattr-23941 [006] d... 10818.945948: p_zfs_zget_0: (zfs_zget+0x0/0x230 [zfs]) zsb=0xffff880016f00000 obj=0xa
        setfattr-23941 [006] d... 10818.945951: r_zfs_zget_0: (zfs_zaccess+0x12b/0x220 [zfs] <- zfs_zget)
        setfattr-23941 [006] d... 10818.945966: p_zfs_mknode_0: (zfs_mknode+0x0/0xe00 [zfs]) flag=0x0 dzp=0xffff88011aa961c0
        setfattr-23941 [006] d... 10818.945990: p_zfs_znode_alloc_0: (zfs_znode_alloc+0x0/0x520 [zfs]) obj=0xc
        setfattr-23941 [006] d... 10818.945996: r_zfs_znode_alloc_0: (zfs_mknode+0x8a3/0xe00 [zfs] <- zfs_znode_alloc) zpp=0xffff88011aa90440

$ rm /zfs/file
           <...>-23942 [006] d... 10822.453456: p_zfs_zget_0: (zfs_zget+0x0/0x230 [zfs]) zsb=0xffff880016f00000 obj=0xa
           <...>-23942 [006] d... 10822.453469: r_zfs_zget_0: (zfs_dirent_lock+0x56c/0x6c0 [zfs] <- zfs_zget)
              rm-23942 [006] d... 10822.453494: p_zfs_zget_0: (zfs_zget+0x0/0x230 [zfs]) zsb=0xffff880016f00000 obj=0xb
              rm-23942 [006] d... 10822.453498: r_zfs_zget_0: (zfs_remove+0x22b/0x4c0 [zfs] <- zfs_zget)
              rm-23942 [006] d... 10822.453597: p_zpl_evict_inode_0: (zpl_evict_inode+0x0/0x60 [zfs]) inode=0xffff88011aa90a90
              rm-23942 [006] d... 10822.453602: p_zfs_inactive_0: (zfs_inactive+0x0/0x270 [zfs]) inode=0xffff88011aa90a90
              rm-23942 [006] d... 10822.453603: p_zfs_zinactive_0: (zfs_zinactive+0x0/0xe0 [zfs]) znode=0xffff88011aa90880 obj=0xa
              rm-23942 [006] d... 10822.453607: p_zfs_rmnode_0: (zfs_rmnode+0x0/0x360 [zfs]) znode=0xffff88011aa90880
              rm-23942 [006] d... 10822.453619: p_zfs_zget_0: (zfs_zget+0x0/0x230 [zfs]) zsb=0xffff880016f00000 obj=0xb
              rm-23942 [006] d... 10822.453623: r_zfs_zget_0: (zfs_rmnode+0x25b/0x360 [zfs] <- zfs_zget)
              rm-23942 [006] d... 10822.453656: p_zfs_iput_async_0: (zfs_iput_async+0x0/0x60 [zfs]) inode=0xffff88011aa963d0 obj=0x0
          z_iput-23904 [006] d... 10822.453675: p_zpl_evict_inode_0: (zpl_evict_inode+0x0/0x60 [zfs]) inode=0xffff88011aa963d0
          z_iput-23904 [006] d... 10822.453676: p_zfs_inactive_0: (zfs_inactive+0x0/0x270 [zfs]) inode=0xffff88011aa963d0
          z_iput-23904 [006] d... 10822.453677: p_zfs_zinactive_0: (zfs_zinactive+0x0/0xe0 [zfs]) znode=0xffff88011aa961c0 obj=0xb
          z_iput-23904 [006] d... 10822.453679: p_zfs_rmnode_0: (zfs_rmnode+0x0/0x360 [zfs]) znode=0xffff88011aa961c0
          z_iput-23904 [006] d... 10822.453681: p_zfs_purgedir_0: (zfs_purgedir+0x0/0x230 [zfs]) znode=0xffff88011aa961c0
          z_iput-23904 [006] d... 10822.453686: p_zfs_zget_0: (zfs_zget+0x0/0x230 [zfs]) zsb=0xffff880016f00000 obj=0xc
          z_iput-23904 [006] d... 10822.453690: r_zfs_zget_0: (zfs_purgedir+0xb4/0x230 [zfs] <- zfs_zget)
          z_iput-23904 [006] d... 10822.453713: p_zfs_iput_async_0: (zfs_iput_async+0x0/0x60 [zfs]) inode=0xffff88011aa90650 obj=0x0
          z_iput-23904 [006] d... 10822.453719: r_zfs_purgedir_0: (zfs_rmnode+0x272/0x360 [zfs] <- zfs_purgedir)
          z_iput-23904 [006] d... 10822.453755: p_zpl_evict_inode_0: (zpl_evict_inode+0x0/0x60 [zfs]) inode=0xffff88011aa90650
          z_iput-23904 [006] d... 10822.453756: p_zfs_inactive_0: (zfs_inactive+0x0/0x270 [zfs]) inode=0xffff88011aa90650
          z_iput-23904 [006] d... 10822.453757: p_zfs_zinactive_0: (zfs_zinactive+0x0/0xe0 [zfs]) znode=0xffff88011aa90440 obj=0xc
          z_iput-23904 [006] d... 10822.453759: p_zfs_rmnode_0: (zfs_rmnode+0x0/0x360 [zfs]) znode=0xffff88011aa90440

$ echo 2 | sudo tee /proc/sys/vm/drop_caches
2
           <...>-23945 [005] d... 10836.555639: p_dispose_list_0: (dispose_list+0x0/0x50)
           <...>-23945 [005] d... 10836.555775: p_dispose_list_0: (dispose_list+0x0/0x50)
           <...>-23945 [005] d... 10836.560865: p_dispose_list_0: (dispose_list+0x0/0x50)
           <...>-23945 [005] d... 10836.560993: p_dispose_list_0: (dispose_list+0x0/0x50)
           <...>-23945 [005] d... 10836.567297: p_dispose_list_0: (dispose_list+0x0/0x50)
           <...>-23945 [005] d... 10836.567371: p_dispose_list_0: (dispose_list+0x0/0x50)