linux-stable/fs
David Howells 4fe6a94682 afs: Try to avoid taking RCU read lock when checking vnode validity
Try to avoid taking the RCU read lock when checking the validity of a
vnode's callback state.  The only thing it's needed for is to pin the
parent volume's server list whilst we search it to find the record of the
server we're currently using to see if it has been reinitialised (ie. it
sent us a CB.InitCallBackState* RPC).

Do this by the following means:

 (1) Keep an additional per-cell counter (fs_s_break) that's incremented
     each time any of the fileservers in the cell reinitialises.

     Since the new counter can be accessed without RCU from the vnode, we
     can check that first - and only if it differs, get the RCU read lock
     and check the volume's server list.

 (2) Replace afs_get_s_break_rcu() with afs_check_server_good() which now
     indicates whether the callback promise is still expected to be present
     on the server.  This does the checks as described in (1).

 (3) Restructure afs_check_validity() to take account of the change in (2).

     We can also get rid of the valid variable and just use the need_clear
     variable with the addition of the afs_cb_break_no_promise reason.

 (4) afs_check_validity() probably shouldn't be altering vnode->cb_v_break
     and vnode->cb_s_break when it doesn't have cb_lock exclusively locked.

     Move the change to vnode->cb_v_break to __afs_break_callback().

     Delegate the change to vnode->cb_s_break to afs_select_fileserver()
     and set vnode->cb_fs_s_break there also.

 (5) afs_validate() no longer needs to get the RCU read lock around its
     call to afs_check_validity() - and can skip the call entirely if we
     don't have a promise.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Markus Suvanto <markus.suvanto@gmail.com>
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/163111669583.283156.1397603105683094563.stgit@warthog.procyon.org.uk/
2021-09-13 09:10:39 +01:00
..
9p fs: remove mandatory file locking support 2021-08-23 06:15:36 -04:00
adfs mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
affs mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
afs afs: Try to avoid taking RCU read lock when checking vnode validity 2021-09-13 09:10:39 +01:00
autofs autofs: should_expire() argument is guaranteed to be positive 2021-03-24 14:14:27 -04:00
befs fs/befs: Delete obsolete TODO file 2021-03-30 16:54:49 -07:00
bfs mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
btrfs for-5.14-rc7-tag 2021-08-26 11:05:11 -07:00
cachefiles fscache, cachefiles: Add alternate API to use kiocb for read/write to cache 2021-04-23 10:14:32 +01:00
ceph File locking changes for v5.15. 2021-08-30 12:38:13 -07:00
cifs \n 2021-08-30 10:24:50 -07:00
coda coda: fix reference counting in coda_file_mmap error path 2021-04-23 14:42:39 -07:00
configfs configfs: restore the kernel v5.13 text attribute write behavior 2021-08-09 16:56:00 +02:00
cramfs
crypto fscrypt: fix derivation of SipHash keys on big endian CPUs 2021-06-05 00:52:52 -07:00
debugfs Linux 5.13-rc6 2021-06-14 09:07:45 +02:00
devpts
dlm fs: dlm: invalid buffer access in lookup error 2021-06-11 12:44:47 -05:00
ecryptfs mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
efivarfs efivars: convert to fileattr 2021-04-12 15:04:29 +02:00
efs
erofs erofs: clean up file headers & footers 2021-06-08 00:41:24 +08:00
exfat Description for this pull request: 2021-07-06 11:06:04 -07:00
exportfs
ext2 \n 2021-08-30 10:24:50 -07:00
ext4 \n 2021-08-30 10:24:50 -07:00
f2fs for-5.15/block-2021-08-30 2021-08-30 18:52:11 -07:00
fat block: move the bdi from the request_queue to the gendisk 2021-08-09 11:53:23 -06:00
freevxfs
fscache fscache, cachefiles: Add alternate API to use kiocb for read/write to cache 2021-04-23 10:14:32 +01:00
fuse \n 2021-08-30 10:24:50 -07:00
gfs2 fs: remove mandatory file locking support 2021-08-23 06:15:36 -04:00
hfs hfs: add lock nesting notation to hfs_find_init 2021-07-15 10:13:49 -07:00
hfsplus hfsplus: report create_date to kstat.btime 2021-07-01 11:06:06 -07:00
hostfs Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-05-02 09:14:01 -07:00
hpfs hpfs: use iomap_fiemap to implement ->fiemap 2021-07-27 11:00:36 +02:00
hugetlbfs hugetlbfs: fix mount mode command line processing 2021-07-23 17:43:28 -07:00
iomap iomap: Don't create iomap_page objects in iomap_page_mkwrite_actor 2021-07-15 09:58:06 -07:00
isofs isofs: joliet: Fix iocharset=utf8 mount option 2021-08-12 16:07:14 +02:00
jbd2 ext4: inline jbd2_journal_[un]register_shrinker() 2021-07-08 08:37:31 -04:00
jffs2 This pull request contains changes for JFFS2, UBI and UBIFS 2021-05-04 18:08:40 -07:00
jfs JFS fixes for 5.14 2021-07-02 14:25:17 -07:00
kernfs Driver core changes for 5.14-rc1 2021-07-05 13:51:41 -07:00
lockd lockd: Update the NLMv4 SHARE results encoder to use struct xdr_stream 2021-07-06 20:14:44 -04:00
minix mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
netfs netfs: fix test for whether we can skip read when writing beyond EOF 2021-06-21 21:24:07 +01:00
nfs fs: remove mandatory file locking support 2021-08-23 06:15:36 -04:00
nfs_common nfs_common: fix doc warning 2021-07-06 20:14:41 -04:00
nfsd fs: remove mandatory file locking support 2021-08-23 06:15:36 -04:00
nilfs2 block: remove the bd_bdi in struct block_device 2021-08-09 11:53:26 -06:00
nls
notify \n 2021-08-30 10:04:31 -07:00
ntfs Merge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-07-03 11:30:04 -07:00
ocfs2 fs: remove mandatory file locking support 2021-08-23 06:15:36 -04:00
omfs mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
openpromfs openpromfs: don't do unlock_new_inode() until the new inode is set up 2021-03-12 22:15:22 -05:00
orangefs orangefs: fix orangefs df output. 2021-06-28 08:40:08 -04:00
overlayfs ovl: fix uninitialized pointer read in ovl_lookup_real_one() 2021-08-10 10:21:30 +02:00
proc Merge branch 'work.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-07-03 11:41:14 -07:00
pstore for-5.14/drivers-2021-06-29 2021-06-30 12:21:16 -07:00
qnx4
qnx6
quota quota: remove unnecessary oom message 2021-06-22 10:40:52 +02:00
ramfs fs: move ramfs_aops to libfs 2021-06-29 10:53:48 -07:00
reiserfs reiserfs: check directory items on read from disk 2021-07-16 12:36:51 +02:00
romfs
squashfs squashfs: use bvec_virt 2021-08-16 10:50:32 -06:00
sysfs
sysv mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
tracefs tracing: Fix various typos in comments 2021-03-23 14:08:18 -04:00
ubifs ubifs: Set/Clear I_LINKABLE under i_lock for whiteout inode 2021-06-22 09:21:39 +02:00
udf udf_get_extendedattr() had no boundary checks. 2021-08-23 13:35:19 +02:00
ufs mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
unicode .gitignore: prefix local generated files with a slash 2021-05-02 00:43:35 +09:00
vboxsf vboxsf: Add support for the atomic_open directory-inode op 2021-06-23 14:36:52 +02:00
verity fsverity: relax build time dependency on CRYPTO_SHA256 2021-04-22 17:31:32 +10:00
xfs for-5.15/block-2021-08-30 2021-08-30 18:52:11 -07:00
zonefs \n 2021-08-30 10:24:50 -07:00
aio.c eventfd: Make signal recursion protection a task bit 2021-08-28 01:33:02 +02:00
anon_inodes.c
attr.c
bad_inode.c
binfmt_aout.c binfmt: remove in-tree usage of MAP_EXECUTABLE 2021-06-29 10:53:50 -07:00
binfmt_elf.c Merge branch 'akpm' (patches from Andrew) 2021-06-29 17:29:11 -07:00
binfmt_elf_fdpic.c Merge branch 'akpm' (patches from Andrew) 2021-06-29 17:29:11 -07:00
binfmt_flat.c binfmt: remove in-tree usage of MAP_EXECUTABLE 2021-06-29 10:53:50 -07:00
binfmt_misc.c binfmt_misc: fix possible deadlock in bm_register_write 2021-03-13 11:27:30 -08:00
binfmt_script.c
block_dev.c io_uring-bio-cache.5-2021-08-30 2021-08-30 19:30:30 -07:00
buffer.c mm/writeback: move __set_page_dirty() to core mm 2021-06-29 10:53:48 -07:00
char_dev.c
compat_binfmt_elf.c
coredump.c Merge branch 'work.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-07-03 11:41:14 -07:00
d_path.c getcwd(2): clean up error handling 2021-05-18 20:15:58 -04:00
dax.c Merge branch 'for-5.14/dax' into libnvdimm-fixes 2021-08-11 12:04:43 -07:00
dcache.c useful constants: struct qstr for ".." 2021-04-15 22:36:45 -04:00
direct-io.c fs: direct-io: fix missing sdio->boundary 2021-04-09 14:54:23 -07:00
drop_caches.c
eventfd.c eventfd: Make signal recursion protection a task bit 2021-08-28 01:33:02 +02:00
eventpoll.c fs/epoll: restore waking from ep_done_scan() 2021-05-06 19:24:13 -07:00
exec.c namei: add getname_uflags() 2021-08-23 13:41:26 -06:00
fcntl.c fcntl: fix potential deadlock for &fasync_struct.fa_lock 2021-08-21 16:20:27 -04:00
fhandle.c switch file_open_root() to struct path 2021-04-07 13:56:43 -04:00
file.c Merge branch 'work.file' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-05-03 11:05:28 -07:00
file_table.c
filesystems.c
fs-writeback.c writeback, cgroup: do not reparent dax inodes 2021-07-23 17:43:28 -07:00
fs_context.c fs: add vfs_parse_fs_param_source() helper 2021-07-14 09:19:06 -07:00
fs_parser.c vfs: fs_parser: clean up kernel-doc warnings 2021-04-30 11:20:35 -07:00
fs_pin.c
fs_struct.c
fs_types.c
fsopen.c
init.c
inode.c mm: Protect operations adding pages to page cache with invalidate_lock 2021-07-13 13:14:27 +02:00
internal.h io_uring: add support for IORING_OP_LINKAT 2021-08-23 13:48:52 -06:00
io-wq.c io-wq: fix wakeup race when adding new work 2021-08-30 07:45:47 -06:00
io-wq.h io-wq: provide a way to limit max number of workers 2021-08-29 07:55:55 -06:00
io_uring.c for-5.15/io_uring-vfs-2021-08-30 2021-08-30 19:39:59 -07:00
ioctl.c fs: remove generic_block_fiemap 2021-07-27 11:00:36 +02:00
Kconfig fs: remove mandatory file locking support 2021-08-23 06:15:36 -04:00
Kconfig.binfmt binfmt: remove support for em86 (alpha only) 2021-07-25 22:33:03 -07:00
kernel_read_file.c switch file_open_root() to struct path 2021-04-07 13:56:43 -04:00
libfs.c fs: remove noop_set_page_dirty() 2021-06-29 10:53:48 -07:00
locks.c fs: remove mandatory file locking support 2021-08-23 06:15:36 -04:00
Makefile binfmt: remove support for em86 (alpha only) 2021-07-25 22:33:03 -07:00
mbcache.c
mount.h
mpage.c block: rename BIO_MAX_PAGES to BIO_MAX_VECS 2021-03-11 07:47:48 -07:00
namei.c for-5.15/io_uring-vfs-2021-08-30 2021-08-30 19:39:59 -07:00
namespace.c fs: remove mandatory file locking support 2021-08-23 06:15:36 -04:00
no-block.c
nsfs.c
open.c fs: remove mandatory file locking support 2021-08-23 06:15:36 -04:00
pipe.c pipe: do FASYNC notifications for every pipe IO, not just state changes 2021-08-25 10:27:16 -07:00
pnode.c
pnode.h mount: fix mounting of detached mounts onto targets that reside on shared mounts 2021-03-08 15:18:43 +01:00
posix_acl.c
proc_namespace.c
read_write.c fs: clean up after mandatory file locking support removal 2021-08-24 07:52:45 -04:00
readdir.c readdir: make sure to verify directory entry for legacy interfaces too 2021-04-17 11:39:49 -07:00
remap_range.c fs: remove mandatory file locking support 2021-08-23 06:15:36 -04:00
select.c kernel, fs: Introduce and use set_restart_fn() and arch_set_restart_data() 2021-03-16 22:13:10 +01:00
seq_file.c seq_file: disallow extremely large seq buffer allocations 2021-07-19 17:18:48 -07:00
signalfd.c signalfd: Remove SIL_PERF_EVENT fields from signalfd_siginfo 2021-05-18 16:20:54 -05:00
splice.c
stack.c
stat.c fs: fix reporting supported extra file attributes for statx() 2021-04-17 23:03:50 -04:00
statfs.c
super.c block: remove the bd_bdi in struct block_device 2021-08-09 11:53:26 -06:00
sync.c
timerfd.c timerfd: Provide timerfd_resume() 2021-08-10 17:57:22 +02:00
userfaultfd.c userfaultfd: do not untag user pointers 2021-07-23 17:43:28 -07:00
utimes.c
xattr.c xattr: fix kernel-doc for mnt_userns and vfs xattr helpers 2021-03-23 11:20:26 +01:00