Oleg Nesterov 967cc53711 kernel: is_current_single_threaded: don't use ->mmap_sem ...

is_current_single_threaded() can safely miss a freshly forked CLONE_VM
task, but in this case it must not miss its parent. That is why we take
mm->mmap_sem for writing to make sure a thread/task with the same ->mm
can't pass exit_mm() and disappear.

However we can avoid ->mmap_sem and rely on rcu/barriers:

	- if we do not see the exiting parent on thread/process list
	  we see the result of list_del_rcu(), in this case we must
	  also see the result of list_add_rcu() which does wmb().

	- if we do see the parent but its ->mm == NULL, we need rmb()
	  to make sure we can't miss the child.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>

2009-07-17 09:11:31 +10:00

..

lzo

lzo: use get/put_unaligned_* helpers

2008-07-25 10:53:26 -07:00

reed_solomon

lib: Remove unnecessary inclusions of asm/semaphore.h

2008-04-18 22:17:17 -04:00

zlib_deflate

lib/: Spelling fixes

2008-02-03 17:48:52 +02:00

zlib_inflate

bzip2/lzma: library support for gzip, bzip2 and lzma decompression

2009-01-04 15:53:34 -08:00

.gitignore

…

argv_split.c

LIB: Replace inappropriate include of <linux/bug.h>

2007-10-20 00:26:10 +02:00

atomic64.c

lib: Provide generic atomic64_t implementation

2009-06-15 13:27:38 +10:00

audit.c

[PATCH] audit signal recipients

2007-05-11 05:38:25 -04:00

bcd.c

rtc: BCD codeshrink

2008-07-24 10:47:33 -07:00

bitmap.c

bitmap: fix end condition in bitmap_find_free_region

2009-03-12 19:32:51 -07:00

bitrev.c

lib: export bitrev16

2008-06-06 11:29:10 -07:00

bug.c

allow bug table entries to use relative pointers (and use it on x86-64)

2008-12-16 18:40:32 +01:00

bust_spinlocks.c

oops handling: ensure that any oops is flushed to the mtdoops console

2009-01-06 15:59:11 -08:00

check_signature.c

uninline check_signature()

2007-07-16 09:05:50 -07:00

checksum.c

lib/checksum.c: fix endianess bug

2009-06-19 14:58:13 +02:00

cmdline.c

generic, memparse(): constify argument

2008-07-28 15:05:23 +02:00

cpumask.c

x86: remove some alloc_bootmem_cpumask_var calling

2009-06-11 19:27:07 +03:00

crc7.c

CRC7 support

2007-07-17 10:23:04 -07:00

crc16.c

…

crc32.c

lib/: Spelling fixes

2008-02-03 17:48:52 +02:00

crc32defs.h

…

crc-ccitt.c

…

crc-itu-t.c

CRC ITU-T V.41

2007-05-10 18:24:13 +02:00

crc-t10dif.c

[SCSI] lib: Add support for the T10 (SCSI) Data Integrity Field CRC

2008-07-12 08:22:32 -05:00

ctype.c

…

debug_locks.c

lockdep: warn about lockdep disabling after kernel taint

2009-04-12 16:10:51 +02:00

debugobjects.c

debugobjects: delay free of internal objects

2009-03-17 12:28:30 +01:00

dec_and_lock.c

atomic: only take lock when the counter drops to zero on UP as well

2009-06-16 19:47:47 -07:00

decompress_bunzip2.c

kmemtrace, kbuild: fix slab.h dependency problem in lib/decompress_bunzip2.c

2009-04-03 12:22:45 +02:00

decompress_inflate.c

kmemtrace, kbuild: fix slab.h dependency problem in lib/decompress_inflate.c

2009-04-03 12:21:36 +02:00

decompress_unlzma.c

kmemtrace, kbuild: fix slab.h dependency problem in lib/decompress_unlzma.c

2009-04-03 12:22:59 +02:00

decompress.c

bzip2/lzma: don't stop search at first unconfigured compression

2009-02-19 13:36:55 -08:00

devres.c

[POWERPC] devres: Add devm_ioremap_prot()

2008-05-05 16:47:14 +10:00

div64.c

add an inlined version of iter_div_u64_rem

2008-06-12 10:47:58 +02:00

dma-debug.c

dma-debug: Fix the overlap() function to be correct and readable

2009-07-10 22:18:45 +02:00

dump_stack.c

…

dynamic_debug.c

Dynamic debug: allow simple quoting of words

2009-03-24 16:38:27 -07:00

extable.c

module: trim exception table on init free.

2009-06-12 21:47:04 +09:30

fault-inject.c

Remove remaining unwinder code

2009-01-06 15:59:11 -08:00

find_last_bit.c

bitmap: find_last_bit()

2009-01-01 10:12:19 +10:30

find_next_bit.c

bitops: remove "optimizations"

2008-04-29 08:11:16 -07:00

gcd.c

lib: add lib/gcd.c

2009-06-18 13:04:05 -07:00

gen_crc32table.c

…

genalloc.c

lib/genalloc.c: remove unmatched write_lock() in gen_pool_destroy

2009-06-16 19:47:53 -07:00

halfmd4.c

…

hexdump.c

hexdump: remove the trailing space

2009-06-16 19:47:51 -07:00

hweight.c

remove asm/bitops.h includes

2007-10-19 11:53:41 -07:00

idr.c

cgroup: CSS ID support

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

inflate.c

inflate: refactor inflate malloc code

2008-07-25 10:53:28 -07:00

int_sqrt.c

…

iomap_copy.c

…

iomap.c

Use WARN() in lib/

2008-07-26 12:00:07 -07:00

iommu-helper.c

introduce generic iommu_num_pages function

2008-10-16 11:21:33 -07:00

ioremap.c

lib/ioremap.c should #include <linux/io.h>

2007-10-17 08:42:50 -07:00

irq_regs.c

…

is_single_threaded.c

kernel: is_current_single_threaded: don't use ->mmap_sem

2009-07-17 09:11:31 +10:00

kasprintf.c

lib: move kasprintf to a separate file

2007-07-31 15:39:39 -07:00

Kconfig

lib: Provide generic atomic64_t implementation

2009-06-15 13:27:38 +10:00

Kconfig.debug

kmemleak: Allow the early log buffer to be configurable.

2009-06-25 10:16:13 +01:00

Kconfig.kgdb

kgdb: remove the requirement for CONFIG_FRAME_POINTER

2008-08-01 08:39:34 -05:00

Kconfig.kmemcheck

kmemcheck: make kconfig accessible for other architectures

2009-06-15 15:49:17 +02:00

kernel_lock.c

sched: TIF_NEED_RESCHED -> need_reshed() cleanup

2009-03-06 12:48:55 +01:00

klist.c

driver core: Remove completion from struct klist_node

2009-01-06 10:44:30 -08:00

kobject_uevent.c

driver core: allow non-root users to listen to uevents

2009-04-16 16:17:09 -07:00

kobject.c

kobject: make kset_create check kobject_set_name return value

2009-06-15 21:30:24 -07:00

kref.c

kref: add kref_set()

2008-01-24 20:40:05 -08:00

libcrc32c.c

libcrc32c: Fix "crc32c undefined" compilation error

2008-12-25 11:01:42 +11:00

list_debug.c

list debugging: use WARN() instead of BUG()

2008-07-25 10:53:29 -07:00

lmb.c

lmb: Rework lmb_dump_all() output

2009-02-11 13:38:00 +11:00

locking-selftest-hardirq.h

…

locking-selftest-mutex.h

…

locking-selftest-rlock-hardirq.h

…

locking-selftest-rlock-softirq.h

…

locking-selftest-rlock.h

…

locking-selftest-rsem.h

…

locking-selftest-softirq.h

…

locking-selftest-spin-hardirq.h

…

locking-selftest-spin-softirq.h

…

locking-selftest-spin.h

…

locking-selftest-wlock-hardirq.h

…

locking-selftest-wlock-softirq.h

…

locking-selftest-wlock.h

…

locking-selftest-wsem.h

…

locking-selftest.c

locking: rename trace_softirq_[enter|exit] => lockdep_softirq_[enter|exit]

2009-03-13 01:32:36 +01:00

Makefile

lib: add lib/gcd.c

2009-06-18 13:04:05 -07:00

nlattr.c

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-next-2.6

2009-03-26 22:45:23 -07:00

parser.c

vfs: Use const for kernel parser table

2008-10-13 10:10:37 -07:00

percpu_counter.c

Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2009-01-06 17:10:04 -08:00

plist.c

Use WARN() in lib/

2008-07-26 12:00:07 -07:00

prio_heap.c

lib: fix sparse shadowed variable warning

2009-01-06 15:59:11 -08:00

prio_tree.c

…

proportions.c

Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2009-01-06 17:10:04 -08:00

radix-tree.c

lib: do code optimization for radix_tree_lookup() and radix_tree_lookup_slot()

2009-06-16 19:47:49 -07:00

random32.c

random32: seeding improvement

2008-07-30 16:29:19 -07:00

ratelimit.c

__ratelimit() cpu flags can't be static

2008-07-28 16:30:20 -07:00

rational.c

lib: isolate rational fractions helper function

2009-06-11 08:51:08 -07:00

rbtree.c

rb_tree: remove redundant if()-condition in rb_erase()

2009-06-16 19:47:56 -07:00

reciprocal_div.c

…

rwsem-spinlock.c

lib: remove fastcall from lib/*

2008-02-08 09:22:31 -08:00

rwsem.c

x86: fix UML and -regparm=3

2008-01-30 13:33:00 +01:00

scatterlist.c

scatterlist: make sure sg_miter_next() doesn't return 0 sized mappings

2009-04-22 08:35:09 +02:00

sha1.c

…

show_mem.c

lib: generic show_mem()

2008-07-26 12:00:10 -07:00

smp_processor_id.c

cpumask: convert lib/smp_processor_id to new cpumask ops

2009-01-30 15:47:34 +01:00

sort.c

generic swap(): lib/sort.c: rename swap to swap_func

2009-01-08 08:31:14 -08:00

spinlock_debug.c

Use helpers to obtain task pid in printks

2007-10-19 11:53:43 -07:00

string_helpers.c

[SCSI] lib: string_get_size(): don't hang on zero; no decimals on exact

2008-10-23 11:42:20 -05:00

string.c

Add a new sysfs_streq() string comparison function

2008-05-01 08:03:59 -07:00

swiotlb.c

swiotlb: change swiotlb_bus_to[phys,virt] prototypes

2009-04-08 16:18:38 +02:00

syscall.c

task_current_syscall

2008-07-26 12:00:10 -07:00

textsearch.c

remove CONFIG_KMOD from lib

2008-07-22 19:24:31 +10:00

ts_bm.c

textsearch: ts_bm: support case insensitive searching in Boyer-Moore algorithm

2008-07-08 02:37:54 -07:00

ts_fsm.c

textsearch: ts_fsm: return error on request for case insensitive search

2008-07-08 02:38:27 -07:00

ts_kmp.c

textsearch: ts_kmp: support case insensitive searching in Knuth-Morris-Pratt algorithm

2008-07-08 02:38:09 -07:00

vsprintf.c

vsprintf: introduce %pf format specifier

2009-04-29 20:55:55 +02:00