Oleg Nesterov 9cd80bbb07 do_wait() optimization: do not place sub-threads on task_struct->children list ...

Thanks to Roland who pointed out de_thread() issues.

Currently we add sub-threads to ->real_parent->children list.  This buys
nothing but slows down do_wait().

With this patch ->children contains only main threads (group leaders).
The only complication is that forget_original_parent() should iterate over
sub-threads by hand, and de_thread() needs another list_replace() when it
changes ->group_leader.

Henceforth do_wait_thread() can never see task_detached() && !EXIT_DEAD
tasks, we can remove this check (and we can unify do_wait_thread() and
ptrace_do_wait()).

This change can confuse the optimistic search in mm_update_next_owner(),
but this is fixable and minor.

Perhaps badness() and oom_kill_process() should be updated, but they
should be fixed in any case.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ratan Nalumasu <rnalumasu@gmail.com>
Cc: Vitaly Mayatskikh <vmayatsk@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2009-12-17 15:45:31 -08:00

..

9p

9p: fix build breakage introduced by FS-Cache

2009-12-01 07:35:11 -08:00

adfs

adfs: remove redundant test on unsigned

2009-09-24 07:21:05 -07:00

affs

affs: add ->sync_fs

2009-06-11 21:36:14 -04:00

afs

afs: remove manual O_SYNC handling

2009-12-10 15:02:50 +01:00

autofs

trivial: remove unnecessary semicolons

2009-09-21 15:14:58 +02:00

autofs4

autofs4: always use lookup for lookup

2009-12-16 07:19:58 -08:00

befs

fs: Make unload_nls() NULL pointer safe

2009-09-24 07:47:42 -04:00

bfs

headers: smp_lock.h redux

2009-07-12 12:22:34 -07:00

btrfs

Revert "task_struct: make journal_info conditional"

2009-12-17 13:23:24 -08:00

cachefiles

Untangling ima mess, part 2: deal with counters

2009-12-16 12:16:47 -05:00

cifs

Merge branch 'for-2.6.33' of git://linux-nfs.org/~bfields/linux

2009-12-16 10:43:34 -08:00

coda

sysctl: Drop & in front of every proc_handler.

2009-11-18 08:37:40 -08:00

configfs

writeback: add name to backing_dev_info

2009-09-11 09:20:26 +02:00

cramfs

fs/cramfs: return f_fsid for statfs(2)

2009-04-02 19:05:08 -07:00

debugfs

debugfs: fix create mutex racy fops and private data

2009-12-11 11:24:53 -08:00

devpts

devpts_get_tty() should validate inode

2009-12-11 15:18:05 -08:00

dlm

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm

2009-12-10 09:33:59 -08:00

ecryptfs

fsstack/ecryptfs: remove unused get_nlinks param to fsstack_copy_attr_all

2009-12-17 10:57:30 -05:00

efs

get rid of BKL in fs/efs

2009-06-17 00:36:36 -04:00

exofs

exofs: Multi-device mirror support

2009-12-10 09:59:23 +02:00

exportfs

nfs: new subdir Documentation/filesystems/nfs

2009-10-27 19:34:04 -04:00

ext2

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6

2009-12-16 12:04:02 -08:00

ext3

sanitize xattr handler prototypes

2009-12-16 12:16:49 -05:00

ext4

Revert "task_struct: make journal_info conditional"

2009-12-17 13:23:24 -08:00

fat

Merge git://git.kernel.org/pub/scm/linux/kernel/git/hirofumi/fatfs-2.6

2009-12-16 10:29:26 -08:00

freevxfs

headers: smp_lock.h redux

2009-07-12 12:22:34 -07:00

fscache

FS-Cache: Avoid maybe-used-uninitialised warning on variable

2009-12-16 07:20:13 -08:00

fuse

fuse: reject O_DIRECT flag also in fuse_create

2009-11-27 16:37:13 +01:00

gfs2

Revert "task_struct: make journal_info conditional"

2009-12-17 13:23:24 -08:00

hfs

hfs: fix a potential buffer overflow

2009-12-15 08:53:10 -08:00

hfsplus

hfsplus: refuse to mount volumes larger than 2TB

2009-10-29 07:39:27 -07:00

hostfs

hostfs: set maximum filesize in superblock for proper LFS support

2009-06-30 18:56:03 -07:00

hpfs

hpfs: use bitmap_weight()

2009-12-16 07:20:06 -08:00

hppfs

hppfs: hppfs_read_file() may return -ERROR

2009-04-02 19:04:53 -07:00

hugetlbfs

Untangling ima mess, part 1: alloc_file()

2009-12-16 12:16:47 -05:00

isofs

Merge branch 'for-2.6.33' of git://linux-nfs.org/~bfields/linux

2009-12-16 10:43:34 -08:00

jbd

Revert "task_struct: make journal_info conditional"

2009-12-17 13:23:24 -08:00

jbd2

Revert "task_struct: make journal_info conditional"

2009-12-17 13:23:24 -08:00

jffs2

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6

2009-12-16 12:04:02 -08:00

jfs

kill I_LOCK

2009-12-17 11:03:25 -05:00

lockd

Merge branch 'for-2.6.33' of git://linux-nfs.org/~bfields/linux

2009-12-16 10:43:34 -08:00

minix

V3 minixfs: add missing directory type checking

2009-09-23 07:39:57 -07:00

ncpfs

tree-wide: fix assorted typos all over the place

2009-12-04 15:39:55 +01:00

nfs

Revert "fix mismerge with Trond's stuff (create_mnt_ns() export is gone now)"

2009-12-17 12:51:05 -08:00

nfs_common

SUNRPC: nfsacl_encode/nfsacl_decode should be exported as GPL-only

2008-12-23 15:21:32 -05:00

nfsd

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6

2009-12-16 12:04:02 -08:00

nilfs2

Revert "task_struct: make journal_info conditional"

2009-12-17 13:23:24 -08:00

nls

Merge git://git.kernel.org/pub/scm/linux/kernel/git/hirofumi/fatfs-2.6

2009-09-30 09:31:14 -07:00

notify

switch alloc_file() to passing struct path

2009-12-16 12:16:42 -05:00

ntfs

kill I_LOCK

2009-12-17 11:03:25 -05:00

ocfs2

ocfs: stop using do_sync_mapping_range

2009-12-16 12:16:49 -05:00

omfs

tree-wide: fix assorted typos all over the place

2009-12-04 15:39:55 +01:00

openpromfs

zero i_uid/i_gid on inode allocation

2009-01-05 11:54:28 -05:00

partitions

partitions: read whole sector with EFI GPT header

2009-11-23 09:29:58 +01:00

proc

Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6

2009-12-16 12:36:49 -08:00

qnx4

qnx4: use hweight8

2009-12-16 07:20:18 -08:00

quota

quota: Implement quota format with 64-bit space and inode limits

2009-12-10 15:02:54 +01:00

ramfs

nommu: ramfs: remove unused local var

2009-12-17 15:45:31 -08:00

reiserfs

reiserfs: truncate blocks not used by a write

2009-12-17 15:45:30 -08:00

romfs

ROMFS: fix length used with romfs_dev_strnlen() function

2009-10-11 11:33:56 -07:00

smbfs

fs: Make unload_nls() NULL pointer safe

2009-09-24 07:47:42 -04:00

squashfs

const: mark remaining super_operations const

2009-09-22 07:17:24 -07:00

sysfs

sysfs: sysfs_setattr remove unnecessary permission check.

2009-12-11 11:24:54 -08:00

sysv

get rid of BKL in fs/sysv

2009-06-17 00:36:37 -04:00

ubifs

kill I_LOCK

2009-12-17 11:03:25 -05:00

udf

udf: Avoid IO in udf_clear_inode

2009-12-14 21:40:04 +01:00

ufs

ufs: NFS support

2009-12-16 07:20:06 -08:00

xfs

kill I_LOCK

2009-12-17 11:03:25 -05:00

aio.c

aio: remove unused field

2009-12-16 07:20:13 -08:00

anon_inodes.c

fs: no games with DCACHE_UNHASHED

2009-12-17 10:51:40 -05:00

attr.c

truncate: new helpers

2009-09-24 08:41:47 -04:00

bad_inode.c

kill ->dir_notify()

2008-12-31 18:07:43 -05:00

binfmt_aout.c

sanitize ifdefs in binfmt_aout

2009-01-03 11:45:54 -08:00

binfmt_elf_fdpic.c

elf: kill USE_ELF_CORE_DUMP

2009-12-16 07:20:12 -08:00

binfmt_elf.c

elf: kill USE_ELF_CORE_DUMP

2009-12-16 07:20:12 -08:00

binfmt_em86.c

…

binfmt_flat.c

flat: use IS_ERR_VALUE() helper macro

2009-09-24 07:21:03 -07:00

binfmt_misc.c

fs/binfmt_misc.c: add terminating newline to /proc/sys/fs/binfmt_misc/status

2009-01-06 15:59:19 -08:00

binfmt_script.c

…

binfmt_som.c

Don't crap into descriptor table in binfmt_som

2009-03-31 23:00:28 -04:00

bio-integrity.c

block: Create bip slabs with embedded integrity vectors

2009-07-01 10:56:25 +02:00

bio.c

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial

2009-12-09 19:43:33 -08:00

block_dev.c

Merge branch 'for-linus' into for-2.6.33

2009-11-03 21:14:39 +01:00

buffer.c

Merge branch 'writeback' of git://git.kernel.dk/linux-2.6-block

2009-09-25 09:27:30 -07:00

char_dev.c

fs/char_dev.c: remove useless loop

2009-09-24 07:21:03 -07:00

compat_binfmt_elf.c

…

compat_ioctl.c

md: move compat_ioctl handling into md.c

2009-12-14 12:51:41 +11:00

compat.c

compat.c: Remove dependence on nfsd private headers

2009-12-14 18:12:10 -05:00

dcache.c

libfs: move EXPORT_SYMBOL for d_alloc_name

2009-12-16 12:16:48 -05:00

dcookies.c

[CVE-2009-0029] System call wrapper special cases

2009-01-14 14:15:18 +01:00

direct-io.c

dio: fix use-after-free

2009-12-17 04:52:13 -05:00

drop_caches.c

sysctl: remove "struct file *" argument of ->proc_handler

2009-09-24 07:21:04 -07:00

eventfd.c

anonfd: split interface into file creation and install

2009-09-23 07:39:29 -07:00

eventpoll.c

sysctl: Drop & in front of every proc_handler.

2009-11-18 08:37:40 -08:00

exec.c

do_wait() optimization: do not place sub-threads on task_struct->children list

2009-12-17 15:45:31 -08:00

fcntl.c

fcntl: rename F_OWNER_GID to F_OWNER_PGRP

2009-11-17 17:40:33 -08:00

fifo.c

…

file_table.c

re-export alloc_file()

2009-12-16 13:29:19 -08:00

file.c

headers: remove sched.h from interrupt.h

2009-10-11 11:20:58 -07:00

filesystems.c

fs: Mark get_filesystem_list() as __init function.

2009-04-20 23:02:52 -04:00

fs_struct.c

Get rid of indirect include of fs_struct.h

2009-03-31 23:00:27 -04:00

fs-writeback.c

writeback: remove unused nonblocking and congestion checks

2009-12-03 13:54:25 +01:00

generic_acl.c

make generic_acl slightly more generic

2009-12-16 12:16:49 -05:00

inode.c

kill I_LOCK

2009-12-17 11:03:25 -05:00

internal.h

fs: move get_empty_filp() deffinition to internal.h

2009-12-16 12:16:45 -05:00

ioctl.c

__generic_block_fiemap(): fix for files bigger than 4GB

2009-11-12 07:26:01 -08:00

ioprio.c

[CVE-2009-0029] System call wrappers part 28

2009-01-14 14:15:30 +01:00

Kconfig

Revert "task_struct: make journal_info conditional"

2009-12-17 13:23:24 -08:00

Kconfig.binfmt

CORE_DUMP_DEFAULT_ELF_HEADERS depends on ELF_CORE

2009-01-09 16:54:41 -08:00

libfs.c

libfs: move EXPORT_SYMBOL for d_alloc_name

2009-12-16 12:16:48 -05:00

locks.c

const: make lock_manager_operations const

2009-09-22 07:17:25 -07:00

Makefile

nilfs2: update makefile and Kconfig

2009-04-07 08:31:16 -07:00

mbcache.c

…

mpage.c

ext4: Properly initialize the buffer_head state

2009-05-13 15:13:42 -04:00

namei.c

vfs: remove extraneous NULL d_inode check from do_filp_open

2009-12-17 10:52:34 -05:00

namespace.c

Revert "fix mismerge with Trond's stuff (create_mnt_ns() export is gone now)"

2009-12-17 12:51:05 -08:00

nfsctl.c

vfs: nfsctl.c un-used nfsd #includes

2009-12-14 18:12:11 -05:00

no-block.c

…

open.c

Untangling ima mess, part 2: deal with counters

2009-12-16 12:16:47 -05:00

pipe.c

fs: no games with DCACHE_UNHASHED

2009-12-17 10:51:40 -05:00

pnode.c

…

pnode.h

…

posix_acl.c

…

read_write.c

sendfile(): check f_op.splice_write() rather than f_op.sendpage()

2009-11-04 09:09:52 +01:00

read_write.h

…

readdir.c

[CVE-2009-0029] System call wrappers part 32

2009-01-14 14:15:31 +01:00

select.c

headers: remove sched.h from poll.h

2009-10-04 15:05:10 -07:00

seq_file.c

vfs: seq_file: add helpers for data filling

2009-09-24 07:47:35 -04:00

signalfd.c

[CVE-2009-0029] System call wrappers part 31

2009-01-14 14:15:31 +01:00

splice.c

sendfile(): check f_op.splice_write() rather than f_op.sendpage()

2009-11-04 09:09:52 +01:00

stack.c

VFS/fsstack: handle 32-bit smp + preempt + large files in fsstack_copy_inode_size

2009-12-17 10:58:17 -05:00

stat.c

kill vfs_stat_fd / vfs_lstat_fd

2009-04-20 23:02:52 -04:00

super.c

freeze_bdev: grab active reference to frozen superblocks

2009-09-24 07:47:41 -04:00

sync.c

fold do_sync_file_range into sys_sync_file_range

2009-12-17 11:03:25 -05:00

timerfd.c

timerfd: add flags check

2009-02-18 15:37:53 -08:00

utimes.c

[CVE-2009-0029] System call wrappers part 30

2009-01-14 14:15:30 +01:00

xattr_acl.c

VFS: Use GFP_NOFS in posix_acl_from_xattr()

2009-12-03 11:48:07 +00:00

xattr.c

sanitize xattr handler prototypes

2009-12-16 12:16:49 -05:00