linux_dsm_epyc7002/fs
David Howells 00e907127e rxrpc: Preallocate peers, conns and calls for incoming service requests
Make it possible for the data_ready handler called from the UDP transport
socket to completely instantiate an rxrpc_call structure and make it
immediately live by preallocating all the memory it might need.  The idea
is to cut out the background thread usage as much as possible.

[Note that the preallocated structs are not actually used in this patch -
 that will be done in a future patch.]

If insufficient resources are available in the preallocation buffers, it
will be possible to discard the DATA packet in the data_ready handler or
schedule a BUSY packet without the need to schedule an attempt at
allocation in a background thread.

To this end:

 (1) Preallocate rxrpc_peer, rxrpc_connection and rxrpc_call structs to a
     maximum number each of the listen backlog size.  The backlog size is
     limited to a maxmimum of 32.  Only this many of each can be in the
     preallocation buffer.

 (2) For userspace sockets, the preallocation is charged initially by
     listen() and will be recharged by accepting or rejecting pending
     new incoming calls.

 (3) For kernel services {,re,dis}charging of the preallocation buffers is
     handled manually.  Two notifier callbacks have to be provided before
     kernel_listen() is invoked:

     (a) An indication that a new call has been instantiated.  This can be
     	 used to trigger background recharging.

     (b) An indication that a call is being discarded.  This is used when
     	 the socket is being released.

     A function, rxrpc_kernel_charge_accept() is called by the kernel
     service to preallocate a single call.  It should be passed the user ID
     to be used for that call and a callback to associate the rxrpc call
     with the kernel service's side of the ID.

 (4) Discard the preallocation when the socket is closed.

 (5) Temporarily bump the refcount on the call allocated in
     rxrpc_incoming_call() so that rxrpc_release_call() can ditch the
     preallocation ref on service calls unconditionally.  This will no
     longer be necessary once the preallocation is used.

Note that this does not yet control the number of active service calls on a
client - that will come in a later patch.

A future development would be to provide a setsockopt() call that allows a
userspace server to manually charge the preallocation buffer.  This would
allow user call IDs to be provided in advance and the awkward manual accept
stage to be bypassed.

Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 11:10:12 +01:00
..
9p 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
adfs 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
affs get rid of 'parent' argument of ->d_compare() 2016-07-31 16:37:25 -04:00
afs rxrpc: Preallocate peers, conns and calls for incoming service requests 2016-09-08 11:10:12 +01:00
autofs4 Merge branch 'work.const-qstr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-08-06 09:49:02 -04:00
befs fs/befs/io.c:befs_bread(): remove unneeded initialization to NULL 2016-05-23 17:04:14 -07:00
bfs more trivial ->iterate_shared conversions 2016-05-09 11:41:14 -04:00
btrfs Merge branch 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2016-08-26 20:22:01 -07:00
cachefiles cachefiles: Fix race between inactivating and culling a cache object 2016-08-03 13:33:26 -04:00
ceph ceph: initialize pathbase in the !dentry case in encode_caps_cb() 2016-08-09 17:26:56 +02:00
cifs get rid of 'parent' argument of ->d_compare() 2016-07-31 16:37:25 -04:00
coda drop redundant ->owner initializations 2016-05-29 19:08:00 -04:00
configfs configfs: don't set buffer_needs_fill to zero if show() returns error 2016-07-10 21:02:18 +09:00
cramfs more trivial ->iterate_shared conversions 2016-05-09 11:41:14 -04:00
crypto block, fs, mm, drivers: use bio set/get op accessors 2016-06-07 13:41:38 -06:00
debugfs Merge branch 'd_real' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs into work.misc 2016-06-30 23:34:49 -04:00
devpts userns: Remove the now unnecessary FS_USERNS_DEV_MOUNT flag 2016-06-23 15:47:31 -05:00
dlm dlm: fix malfunction of dlm_tool caused by debugfs changes 2016-08-26 13:22:14 -05:00
ecryptfs ecryptfs: don't allow mmap when the lower fs doesn't support it 2016-07-08 10:35:28 -05:00
efivarfs get rid of 'parent' argument of ->d_compare() 2016-07-31 16:37:25 -04:00
efs fs/efs/super.c: fix return value 2016-05-20 17:58:30 -07:00
exofs block, fs, mm, drivers: use bio set/get op accessors 2016-06-07 13:41:38 -06:00
exportfs introduce a parallel variant of ->iterate() 2016-05-02 19:49:29 -04:00
ext2 Merge branch 'work.const-qstr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-08-06 09:49:02 -04:00
ext4 Fix bugs that could cause kernel deadlocks or file system corruption 2016-08-29 12:37:11 -07:00
f2fs f2fs: avoid potential deadlock in f2fs_move_file_range 2016-08-19 11:15:08 +09:00
fat 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
freevxfs freevxfs: update Kconfig information 2016-06-13 10:20:39 +02:00
fscache Merge branch 'd_real' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs into work.misc 2016-06-30 23:34:49 -04:00
fuse Merge branch 'work.const-qstr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-08-06 09:49:02 -04:00
gfs2 fs: return EPERM on immutable inode 2016-08-07 10:03:31 -04:00
hfs 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
hfsplus 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
hostfs hostfs: Freeing an ERR_PTR in hostfs_fill_sb_common() 2016-08-04 00:18:10 +02:00
hpfs get rid of 'parent' argument of ->d_compare() 2016-07-31 16:37:25 -04:00
hugetlbfs mm, fs: remove remaining PAGE_CACHE_* and page_cache_{get,release} usage 2016-04-04 10:41:08 -07:00
isofs get rid of 'parent' argument of ->d_compare() 2016-07-31 16:37:25 -04:00
jbd2 The major change this cycle is deleting ext4's copy of the file system 2016-07-26 18:35:55 -07:00
jffs2 vfs: make the string hashes salt the hash 2016-06-10 20:21:46 -07:00
jfs get rid of 'parent' argument of ->d_compare() 2016-07-31 16:37:25 -04:00
kernfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2016-07-29 15:54:19 -07:00
lockd Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-07-28 12:59:05 -07:00
logfs Merge branch 'work.const-qstr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-08-06 09:49:02 -04:00
minix simple local filesystems: switch to ->iterate_shared() 2016-05-02 19:49:32 -04:00
ncpfs get rid of 'parent' argument of ->d_compare() 2016-07-31 16:37:25 -04:00
nfs NFS client bugfixes for Linux 4.8 2016-08-12 12:32:24 -07:00
nfs_common
nfsd nfsd: don't return an unhashed lock stateid after taking mutex 2016-08-12 16:10:25 -04:00
nilfs2 nilfs2: move ioctl interface and disk layout to uapi separately 2016-08-02 19:35:21 -04:00
nls
notify fsnotify: avoid spurious EMFILE errors from inotify_init() 2016-05-19 19:12:14 -07:00
ntfs Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-07-28 12:59:05 -07:00
ocfs2 Merge branch 'work.const-qstr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-08-06 09:49:02 -04:00
omfs more trivial ->iterate_shared conversions 2016-05-09 11:41:14 -04:00
openpromfs more trivial ->iterate_shared conversions 2016-05-09 11:41:14 -04:00
orangefs orangefs: Account for jiffies wraparound. 2016-08-02 15:39:13 -04:00
overlayfs ovl: simplify empty checking 2016-07-29 12:05:25 +02:00
proc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-08-18 01:17:32 -04:00
pstore ramoops: use persistent_ram_free() instead of kfree() for freeing prz 2016-08-05 11:21:46 -07:00
qnx4 more trivial ->iterate_shared conversions 2016-05-09 11:41:14 -04:00
qnx6 more trivial ->iterate_shared conversions 2016-05-09 11:41:14 -04:00
quota Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2016-07-29 15:54:19 -07:00
ramfs tmpfs/ramfs: fix VM_MAYSHARE mappings for NOMMU 2016-05-20 17:58:30 -07:00
reiserfs reiserfs: fix "new_insert_key may be used uninitialized ..." 2016-08-02 19:35:22 -04:00
romfs romfs, squashfs: switch to ->iterate_shared() 2016-05-09 11:41:15 -04:00
squashfs fs: have ll_rw_block users pass in op and flags separately 2016-06-07 13:41:38 -06:00
sysfs kernfs: The cgroup filesystem also benefits from SB_I_NOEXEC 2016-06-23 15:41:56 -05:00
sysv vfs: make the string hashes salt the hash 2016-06-10 20:21:46 -07:00
tracefs tracefs: ->d_parent is never NULL or negative... 2016-05-29 16:22:07 -04:00
ubifs ubifs: Fix xattr generic handler usage 2016-08-23 23:02:52 +02:00
udf Merge branch 'for-4.8/drivers' of git://git.kernel.dk/linux-block 2016-07-26 15:37:51 -07:00
ufs Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-07-28 12:59:05 -07:00
xfs Merge branch 'iomap-fixes-4.8-rc3' into for-next 2016-08-17 11:13:37 +10:00
aio.c aio: make aio_setup_ring killable 2016-05-23 17:04:14 -07:00
anon_inodes.c
attr.c vfs: Don't modify inodes with a uid or gid unknown to the vfs 2016-07-05 15:06:46 -05:00
bad_inode.c switch ->setxattr() to passing dentry and inode separately 2016-05-27 20:09:16 -04:00
binfmt_aout.c fs: fix binfmt_aout.c build error 2016-05-28 16:34:59 -07:00
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: fix calculations for bss padding 2016-08-02 19:35:14 -04:00
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 binfmt_misc for-linus on 20160727 2016-08-07 10:13:14 -04:00
binfmt_script.c
block_dev.c fs/block_dev: fix potential NULL ptr deref in freeze_bdev() 2016-08-25 08:38:26 -06:00
buffer.c xfs: update for 4.8-rc1 2016-07-27 09:53:35 -07:00
char_dev.c chardev: add missing line break in pr_warn 2016-07-14 16:21:53 +09:00
compat_binfmt_elf.c
compat_ioctl.c [media] cec: add compat32 ioctl support 2016-06-28 10:00:13 -03:00
compat.c Fix a number of bugs, most notably a potential stale data exposure 2016-05-24 12:55:26 -07:00
coredump.c coredump: fix dumping through pipes 2016-06-07 22:07:09 -04:00
dax.c libnvdimm for 4.8 2016-07-28 17:38:16 -07:00
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 direct-io: use bio set/get op accessors 2016-06-07 13:41:38 -06:00
drop_caches.c
eventfd.c eventfd: document lockless access in eventfd_poll 2016-03-22 15:36:02 -07:00
eventpoll.c fs: poll/select/recvmmsg: use timespec64 for timeout events 2016-05-19 19:12:14 -07:00
exec.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu 2016-08-04 18:04:44 -04:00
fcntl.c
fhandle.c fs/coredump: prevent fsuid=0 dumps into user-controlled directories 2016-03-22 15:36:02 -07:00
file_table.c
file.c give readdir(2)/getdents(2)/etc. uniform exclusion with lseek() 2016-05-02 19:49:28 -04:00
filesystems.c
fs_pin.c
fs_struct.c
fs-writeback.c mm, writeback: flush plugged IO in wakeup_flusher_threads() 2016-08-09 19:58:06 -06:00
inode.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
internal.h binfmt_misc for-linus on 20160727 2016-08-07 10:13:14 -04:00
ioctl.c vfs: ioctl: prevent double-fetch in dedupe ioctl 2016-07-28 15:23:12 -07:00
iomap.c iomap: mark ->iomap_end as optional 2016-08-17 08:42:34 +10:00
Kconfig Highlights: 2016-08-04 19:59:06 -04:00
Kconfig.binfmt m68k: enable binfmt_flat on systems with an MMU 2016-07-28 13:29:13 +10:00
libfs.c lockless next_positive() 2016-06-20 17:11:29 -04:00
locks.c locks: use file_inode() 2016-07-01 10:24:18 -04:00
Makefile fs: introduce iomap infrastructure 2016-06-21 09:23:11 +10:00
mbcache.c mbcache: add reusable flag to cache entries 2016-02-22 22:44:04 -05:00
mount.h
mpage.c block/mm: make bdev_ops->rw_page() take a bool for read/write 2016-08-07 14:41:02 -06:00
namei.c fs: return EPERM on immutable inode 2016-08-07 10:03:31 -04:00
namespace.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2016-07-29 15:54:19 -07:00
no-block.c
nsfs.c
open.c binfmt_misc for-linus on 20160727 2016-08-07 10:13:14 -04:00
pipe.c mm: memcontrol: only mark charged pages with PageKmemcg 2016-08-09 10:14:10 -07:00
pnode.c propogate_mnt: Handle the first propogated copy being a slave 2016-05-05 09:54:45 -05:00
pnode.h
posix_acl.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2016-07-29 15:54:19 -07:00
proc_namespace.c vfs: show_vfsstat: do not ignore errors from show_devname method 2016-03-16 13:09:08 -04:00
read_write.c x86/syscalls: Add compat_sys_preadv64v2/compat_sys_pwritev64v2 2016-07-15 10:30:26 +02:00
readdir.c restore killability of old mutex_lock_killable(&inode->i_mutex) users 2016-05-26 00:13:25 -04:00
select.c fs: poll/select/recvmmsg: use timespec64 for timeout events 2016-05-19 19:12:14 -07:00
seq_file.c fs/seq_file: fix out-of-bounds read 2016-08-26 17:39:35 -07:00
signalfd.c
splice.c Merge branch 'ovl-fixes' into for-linus 2016-05-11 00:00:29 -04:00
stack.c
stat.c
statfs.c
super.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2016-07-29 15:54:19 -07:00
sync.c mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros 2016-04-04 10:41:08 -07:00
timerfd.c timerfd: Reject ALARM timerfds without CAP_WAKE_ALARM 2016-06-09 23:42:38 +02:00
userfaultfd.c mm: introduce fault_env 2016-07-26 16:19:19 -07:00
utimes.c fs: return EPERM on immutable inode 2016-08-07 10:03:31 -04:00
xattr.c vfs: Don't modify inodes with a uid or gid unknown to the vfs 2016-07-05 15:06:46 -05:00