linux/fs
Matthew Wilcox 148deab223 radix-tree: improve multiorder iterators
This fixes several interlinked problems with the iterators in the
presence of multiorder entries.

1. radix_tree_iter_next() would only advance by one slot, which would
   result in the iterators returning the same entry more than once if
   there were sibling entries.

2. radix_tree_next_slot() could return an internal pointer instead of
   a user pointer if a tagged multiorder entry was immediately followed by
   an entry of lower order.

3. radix_tree_next_slot() expanded to a lot more code than it used to
   when multiorder support was compiled in.  And I wasn't comfortable with
   entry_to_node() being in a header file.

Fixing radix_tree_iter_next() for the presence of sibling entries
necessarily involves examining the contents of the radix tree, so we now
need to pass 'slot' to radix_tree_iter_next(), and we need to change the
calling convention so it is called *before* dropping the lock which
protects the tree.  Also rename it to radix_tree_iter_resume(), as some
people thought it was necessary to call radix_tree_iter_next() each time
around the loop.

radix_tree_next_slot() becomes closer to how it looked before multiorder
support was introduced.  It only checks to see if the next entry in the
chunk is a sibling entry or a pointer to a node; this should be rare
enough that handling this case out of line is not a performance impact
(and such impact is amortised by the fact that the entry we just
processed was a multiorder entry).  Also, radix_tree_next_slot() used to
force a new chunk lookup for untagged entries, which is more expensive
than the out of line sibling entry skipping.

Link: http://lkml.kernel.org/r/1480369871-5271-55-git-send-email-mawilcox@linuxonhyperv.com
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-14 16:04:10 -08:00
..
9p block,fs: untangle fs.h and blk_types.h 2016-11-01 09:43:26 -06:00
adfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
affs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
afs afs: call->operation_ID sometimes used as __be32 sometimes as u32 2016-10-13 17:03:52 +01:00
autofs4 autofs: refactor ioctl fn vector in iookup_dev_ioctl() 2016-10-11 15:06:31 -07:00
befs befs fixes for 4.9-rc1 2016-10-15 12:09:13 -07:00
bfs Merge remote-tracking branch 'ovl/rename2' into for-linus 2016-10-10 23:02:51 -04:00
btrfs radix-tree: improve multiorder iterators 2016-12-14 16:04:10 -08:00
cachefiles Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
ceph ceph: don't set req->r_locked_dir in ceph_d_revalidate 2016-12-08 14:32:16 +01:00
cifs Merge branch 'for-4.10/block' of git://git.kernel.dk/linux-block 2016-12-13 10:19:16 -08:00
coda Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
configfs Merge remote-tracking branch 'ovl/rename2' into for-linus 2016-10-10 23:02:51 -04:00
cramfs
crypto fscrypt: Rename FS_WRITE_PATH_FL to FS_CTX_HAS_BOUNCE_BUFFER_FL 2016-12-11 16:33:18 -05:00
debugfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
devpts Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
dlm dlm for 4.10 2016-12-14 08:31:37 -08:00
ecryptfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
efivarfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
efs
exofs fs: exofs: print a hex number after a 0x prefix 2016-10-27 18:43:43 -07:00
exportfs exportfs: be careful to only return expected errors. 2016-10-06 09:07:44 -04:00
ext2 ext2: use iomap_zero_range() for zeroing truncated page in DAX path 2016-11-20 20:47:07 -05:00
ext4 This merge request includes the dax-4.0-iomap-pmd branch which is 2016-12-14 09:17:42 -08:00
f2fs This merge request includes the dax-4.0-iomap-pmd branch which is 2016-12-14 09:17:42 -08:00
fat Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
freevxfs
fscache
fuse fuse: fix clearing suid, sgid for chown() 2016-12-06 16:18:45 +01:00
gfs2 writeback: add wbc_to_write_flags() 2016-11-02 10:24:03 -06:00
hfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
hfsplus block,fs: use REQ_* flags directly 2016-11-01 09:43:26 -06:00
hostfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
hpfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
hugetlbfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
isofs Merge branch 'for-4.10/block' of git://git.kernel.dk/linux-block 2016-12-13 10:19:16 -08:00
jbd2 Merge branch 'for-4.10/block' of git://git.kernel.dk/linux-block 2016-12-13 10:19:16 -08:00
jffs2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
jfs The jfs piece of the current_time() series. 2016-12-14 08:30:08 -08:00
kernfs kernfs: Declare two local data structures static 2016-11-29 20:58:31 +01:00
lockd netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
logfs fs: logfs: remove unnecesary check 2016-11-22 08:57:55 -07:00
minix Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
ncpfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
nfs Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-11-26 23:42:21 -05:00
nfs_common netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
nfsd netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
nilfs2 block,fs: use REQ_* flags directly 2016-11-01 09:43:26 -06:00
nls
notify fsnotify: clean up spinlock assertions 2016-10-07 18:46:26 -07:00
ntfs Merge branch 'for-4.10/block' of git://git.kernel.dk/linux-block 2016-12-13 10:19:16 -08:00
ocfs2 Merge branch 'for-4.10/block' of git://git.kernel.dk/linux-block 2016-12-13 10:19:16 -08:00
omfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
openpromfs fs: Replace CURRENT_TIME with current_time() for inode timestamps 2016-09-27 21:06:21 -04:00
orangefs Merge branch 'for-4.10/block' of git://git.kernel.dk/linux-block 2016-12-13 10:19:16 -08:00
overlayfs ovl: fix d_real() for stacked fs 2016-11-29 10:20:24 +01:00
proc xen: features and fixes for 4.10 rc0 2016-12-13 16:07:55 -08:00
pstore Improvements and fixes to pstore subsystem: 2016-12-13 09:16:11 -08:00
qnx4
qnx6
quota genetlink: mark families as __ro_after_init 2016-10-27 16:16:09 -04:00
ramfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
reiserfs mm: only include blk_types in swap.h if CONFIG_SWAP is enabled 2016-11-01 09:43:26 -06:00
romfs
squashfs block,fs: untangle fs.h and blk_types.h 2016-11-01 09:43:26 -06:00
sysfs Merge branch 'for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 2016-10-14 12:18:50 -07:00
sysv Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
tracefs fs: Replace CURRENT_TIME with current_time() for inode timestamps 2016-09-27 21:06:21 -04:00
ubifs ubifs: Fix regression in ubifs_readdir() 2016-10-28 14:48:31 +02:00
udf block,fs: untangle fs.h and blk_types.h 2016-11-01 09:43:26 -06:00
ufs block,fs: untangle fs.h and blk_types.h 2016-11-01 09:43:26 -06:00
xfs This merge request includes the dax-4.0-iomap-pmd branch which is 2016-12-14 09:17:42 -08:00
aio.c aio: fix freeze protection of aio writes 2016-10-30 13:09:42 -04:00
anon_inodes.c
attr.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
bad_inode.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
binfmt_aout.c
binfmt_elf_fdpic.c elf_fdpic_transfer_args_to_stack(): make it generic 2016-07-25 16:51:49 +10:00
binfmt_elf.c binfmt_elf: use vmalloc() for allocation of vma_filesz 2016-12-12 18:55:10 -08:00
binfmt_em86.c fs/binfmt_em86.c: fix incompatible pointer type 2016-08-02 19:35:15 -04:00
binfmt_flat.c binfmt_flat: allow compressed flat binary format to work on MMU systems 2016-07-28 13:29:12 +10:00
binfmt_misc.c fs: Replace current_fs_time() with current_time() 2016-09-27 21:06:22 -04:00
binfmt_script.c
block_dev.c block: protect iterate_bdevs() against concurrent close 2016-12-01 08:26:39 -07:00
buffer.c Merge branch 'for-4.10/block' of git://git.kernel.dk/linux-block 2016-12-13 10:19:16 -08:00
char_dev.c dax: define a unified inode/address_space for device-dax mappings 2016-08-23 22:58:51 -07:00
compat_binfmt_elf.c
compat_ioctl.c fs: compat_ioctl: add pretimeout functions for watchdogs 2016-09-24 09:27:18 +02:00
compat.c compat: remove compat_printk() 2016-09-27 21:20:53 -04:00
coredump.c coredump: fix unfreezable coredumping task 2016-11-11 08:12:37 -08:00
dax.c dax: clear dirty entry tags on cache flush 2016-12-14 16:04:09 -08:00
dcache.c Merge branch 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-08-07 10:01:14 -04:00
dcookies.c
direct-io.c block: move poll code to blk-mq 2016-11-11 13:40:25 -07:00
drop_caches.c
eventfd.c
eventpoll.c
exec.c mm: add locked parameter to get_user_pages_remote() 2016-12-14 16:04:08 -08:00
fcntl.c
fhandle.c
file_table.c
file.c fs/file: more unsigned file descriptors 2016-09-27 18:47:38 -04:00
filesystems.c
fs_pin.c
fs_struct.c
fs-writeback.c fs/fs-writeback.c: remove redundant if check 2016-12-12 18:55:08 -08:00
inode.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
internal.h Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 13:04:49 -07:00
ioctl.c vfs: cap dedupe request structure size at PAGE_SIZE 2016-09-15 13:29:52 -07:00
iomap.c Merge branch 'dax-4.10-iomap-pmd' into origin 2016-11-13 22:02:15 -05:00
Kconfig dax: remove "depends on BROKEN" from FS_DAX_PMD 2016-11-08 11:35:16 +11:00
Kconfig.binfmt docs: fix locations of several documents that got moved 2016-10-24 08:12:35 -02:00
libfs.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
locks.c locking, fs/locks: Add missing file_sem locks 2016-10-18 12:21:28 +02:00
Makefile
mbcache.c mbcache: document that "find" functions only return reusable entries 2016-12-03 15:55:01 -05:00
mount.h mnt: Add a per mount namespace limit on the number of mounts 2016-09-30 12:46:48 -05:00
mpage.c writeback: add wbc_to_write_flags() 2016-11-02 10:24:03 -06:00
namei.c Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2016-10-14 17:23:33 -07:00
namespace.c This adds a new gcc plugin named "latent_entropy". It is designed to 2016-10-15 10:03:15 -07:00
no-block.c
nsfs.c net: add an ioctl to get a socket network namespace 2016-10-31 10:56:36 -04:00
open.c xfs: reflink update for 4.9-rc1 2016-10-13 20:28:22 -07:00
pipe.c pipe: cap initial pipe capacity according to pipe-max-size limit 2016-10-11 15:06:32 -07:00
pnode.c mnt: Add a per mount namespace limit on the number of mounts 2016-09-30 12:46:48 -05:00
pnode.h mnt: Add a per mount namespace limit on the number of mounts 2016-09-30 12:46:48 -05:00
posix_acl.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
proc_namespace.c
read_write.c iov_iter: kernel-doc import_iovec() and rw_copy_check_uvector() 2016-10-14 20:00:34 -04:00
readdir.c
select.c fs/select: add vmalloc fallback for select(2) 2016-10-11 15:06:30 -07:00
seq_file.c seq/proc: modify seq_put_decimal_[u]ll to take a const char *, not char 2016-10-07 18:46:30 -07:00
signalfd.c
splice.c Merge branch 'for-4.10/block' of git://git.kernel.dk/linux-block 2016-12-13 10:19:16 -08:00
stack.c
stat.c
statfs.c
super.c fs/super.c: don't fool lockdep in freeze_super() and thaw_super() paths 2016-10-14 20:41:59 -04:00
sync.c
timerfd.c
userfaultfd.c mm: join struct fault_env and vm_fault 2016-12-14 16:04:09 -08:00
utimes.c Merge remote-tracking branch 'jk/vfs' into work.misc 2016-10-08 11:06:08 -04:00
xattr.c xattr: Fix setting security xattrs on sockfs 2016-11-17 00:00:23 -05:00