Huang Ying f49f23abf3 lib, Add lock-less NULL terminated single list ... Cmpxchg is used to implement adding new entry to the list, deleting all entries from the list, deleting first entry of the list and some other operations. Because this is a single list, so the tail can not be accessed in O(1). If there are multiple producers and multiple consumers, llist_add can be used in producers and llist_del_all can be used in consumers. They can work simultaneously without lock. But llist_del_first can not be used here. Because llist_del_first depends on list->first->next does not changed if list->first is not changed during its operation, but llist_del_first, llist_add, llist_add (or llist_del_all, llist_add, llist_add) sequence in another consumer may violate that. If there are multiple producers and one consumer, llist_add can be used in producers and llist_del_all or llist_del_first can be used in the consumer. This can be summarized as follow: | add | del_first | del_all add | - | - | - del_first | | L | L del_all | | | - Where "-" stands for no lock is needed, while "L" stands for lock is needed. The list entries deleted via llist_del_all can be traversed with traversing function such as llist_for_each etc. But the list entries can not be traversed safely before deleted from the list. The order of deleted entries is from the newest to the oldest added one. If you want to traverse from the oldest to the newest, you must reverse the order by yourself before traversing. The basic atomic operation of this list is cmpxchg on long. On architectures that don't have NMI-safe cmpxchg implementation, the list can NOT be used in NMI handler. So code uses the list in NMI handler should depend on CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG. Signed-off-by: Huang Ying <ying.huang@intel.com> Reviewed-by: Andi Kleen <ak@linux.intel.com> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>		2011-08-03 11:15:56 -04:00
..
lzo	lib: add support for LZO-compressed kernels	2010-01-11 09:34:04 -08:00
raid6	Move .gitignore from drivers/md to lib/raid6	2010-08-30 17:35:52 +10:00
reed_solomon
xz	XZ decompressor: Fix decoding of empty LZMA2 streams	2011-05-02 08:46:12 -07:00
zlib_deflate	zlib: slim down zlib_deflate() workspace when possible	2011-03-22 17:44:17 -07:00
zlib_inflate	inflate_fast: sout is already a short so ptr arith was off by one.	2010-03-12 15:52:44 -08:00
.gitignore
argv_split.c	tree-wide: convert open calls to remove spaces to skip_spaces() lib function	2009-12-15 08:53:32 -08:00
atomic64.c	lib: Fix atomic64_add_unless return value convention	2010-03-01 11:38:46 -08:00
atomic64_test.c	ARM: 6213/1: atomic64_test: add ARM as supported architecture	2010-07-27 10:43:46 +01:00
audit.c	audit: support the "standard" <asm-generic/unistd.h>	2011-05-04 14:41:28 -04:00
average.c	lib: Improve EWMA efficiency by using bitshifts	2010-12-06 15:58:43 -05:00
bcd.c
bch.c	lib: add shared BCH ECC library	2011-03-11 14:25:50 +00:00
bitmap.c	lib/bitmap.c: fix kernel-doc notation	2011-06-15 20:03:59 -07:00
bitrev.c
bsearch.c	lib: Add generic binary search function to the kernel.	2011-05-19 16:55:27 +09:30
btree.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
bug.c	modules: Fix module_bug_list list corruption race	2010-10-05 11:29:27 -07:00
bust_spinlocks.c
check_signature.c
checksum.c
cmdline.c
cpu-notifier-error-inject.c	fault-injection: add CPU notifier error injection module	2010-05-27 09:12:48 -07:00
cpu_rmap.c	lib: cpu_rmap: CPU affinity reverse-mapping	2011-01-24 14:51:56 -08:00
cpumask.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
crc-ccitt.c
crc-itu-t.c
crc-t10dif.c
crc7.c
crc16.c
crc32.c	revert "crc32: use __BYTE_ORDER macro for endian detection"	2010-05-26 08:19:23 -07:00
crc32defs.h
ctype.c	ctype: constify read-only _ctype string	2009-12-15 08:53:32 -08:00
debug_locks.c	Revert "debug_locks: set oops_in_progress if we will log messages."	2010-11-29 15:18:28 -08:00
debugobjects.c	debugobjects: Fix boot crash when kmemleak and debugobjects enabled	2011-06-20 14:38:43 +02:00
dec_and_lock.c
decompress.c	decompressors: add boot-time XZ support	2011-01-13 08:03:25 -08:00
decompress_bunzip2.c	Decompressors: include <linux/slab.h> in <linux/decompress/mm.h>	2011-01-13 08:03:23 -08:00
decompress_inflate.c	decompressors: check input size in decompress_inflate.c	2011-01-13 08:03:25 -08:00
decompress_unlzma.c	Decompressors: validate match distance in decompress_unlzma.c	2011-01-13 08:03:24 -08:00
decompress_unlzo.c	Decompressors: fix callback-to-callback mode in decompress_unlzo.c	2011-01-13 08:03:24 -08:00
decompress_unxz.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
devres.c	lib/devres.c: fix comment typo	2010-07-11 22:16:32 +02:00
div64.c	div64_u64(): improve precision on 32bit platforms	2010-10-26 16:52:19 -07:00
dma-debug.c	dma-debug: print information about leaked entry	2011-04-07 16:31:19 +02:00
dump_stack.c
dynamic_debug.c	dynamic_debug: add #include <linux/sched.h>	2011-02-03 15:59:58 -08:00
extable.c
fault-inject.c
find_last_bit.c	bitops: add #ifndef for each of find bitops	2011-05-26 17:12:38 -07:00
find_next_bit.c	arch: remove CONFIG_GENERIC_FIND_{NEXT_BIT,BIT_LE,LAST_BIT}	2011-05-26 17:12:38 -07:00
flex_array.c	flex_array: avoid divisions when accessing elements	2011-05-26 17:12:33 -07:00
gcd.c
gen_crc32table.c	crc32: major optimization	2010-05-25 08:07:06 -07:00
genalloc.c	lib/genalloc.c: add support for specifying the physical address	2011-05-25 08:39:54 -07:00
halfmd4.c
hexdump.c	include/linux/printk.h lib/hexdump.c: neatening and add CONFIG_PRINTK guard	2011-01-13 08:03:10 -08:00
hweight.c	x86: Add optimized popcnt variants	2010-04-06 15:52:11 -07:00
idr.c	docbook: add idr/ida to kernel-api docbook	2010-10-26 17:40:56 -07:00
inflate.c	MN10300: Don't try and #include <linux/slab.h> in lib/inflate.c from bootloader	2010-08-12 09:51:35 -07:00
int_sqrt.c
iomap.c
iomap_copy.c
iommu-helper.c	iommu: inline iommu_num_pages	2010-08-09 20:45:05 -07:00
ioremap.c	ACPI, APEI, Generic Hardware Error Source POLL/IRQ/NMI notification type support	2011-01-12 03:06:19 -05:00
irq_regs.c
is_single_threaded.c
kasprintf.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
Kconfig	lib, Add lock-less NULL terminated single list	2011-08-03 11:15:56 -04:00
Kconfig.debug	tile: enable CONFIG_BUGVERBOSE	2011-06-01 16:06:04 -04:00
Kconfig.kgdb	mips,kgdb: kdb low level trap catch and stack trace	2010-05-20 21:04:26 -05:00
Kconfig.kmemcheck
klist.c
kobject.c	Delay struct net freeing while there's a sysfs instance refering to it	2011-06-12 17:45:41 -04:00
kobject_uevent.c	kobject_uevent: fix typo in comments	2010-08-23 18:12:46 -07:00
kref.c	kref: Add a kref_sub function	2010-11-22 13:25:13 +10:00
kstrtox.c	lib: add kstrto*_from_user()	2011-05-25 08:39:52 -07:00
lcm.c	block: Fix overrun in lcm() and move it to lib	2010-03-15 12:47:59 +01:00
libcrc32c.c
list_debug.c	Expand CONFIG_DEBUG_LIST to several other list operations	2011-02-18 11:32:28 -08:00
list_sort.c	lib/list_sort: test: check element addresses	2010-10-26 16:52:19 -07:00
llist.c	lib, Add lock-less NULL terminated single list	2011-08-03 11:15:56 -04:00
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	rcu: Fix unpaired rcu_irq_enter() from locking selftests	2011-05-26 09:42:19 -07:00
lru_cache.c	lru_cache: use correct type in sizeof for allocation	2011-05-25 08:39:52 -07:00
Makefile	lib, Add lock-less NULL terminated single list	2011-08-03 11:15:56 -04:00
nlattr.c	net: fix nla_policy_len to actually _iterate_ over the policy	2011-02-28 12:38:25 -08:00
parser.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
percpu_counter.c	percpucounter: Optimize __percpu_counter_add a bit through the use of this_cpu() options.	2010-12-17 15:07:18 +01:00
plist.c	plist: Add priority list test	2011-03-11 15:14:48 -05:00
prio_heap.c
prio_tree.c
proportions.c
radix-tree.c	radix_tree: radix_tree_gang_lookup_tag_slot() may never return	2011-01-26 10:50:04 +10:00
random32.c	Merge branch 'master' into for-next	2010-06-16 18:08:13 +02:00
ratelimit.c	ratelimit: fix the return value when __ratelimit() fails to acquire the lock	2010-04-07 08:38:04 -07:00
rational.c	lib/rational.c needs module.h	2010-01-11 09:34:05 -08:00
rbtree.c	Export the augmented rbtree helper functions	2011-01-28 12:16:59 +10:00
reciprocal_div.c
rwsem-spinlock.c	rwsem generic spinlock: use IRQ save/restore spinlocks	2010-04-07 16:15:05 -07:00
rwsem.c	rwsem: Remove redundant asmregparm annotation	2011-01-27 12:30:40 +01:00
scatterlist.c	scatterlist: prevent invalid free when alloc fails	2010-08-30 19:55:09 +02:00
sha1.c
show_mem.c	arch, mm: filter disallowed nodes from arch specific show_mem functions	2011-05-25 08:39:03 -07:00
smp_processor_id.c
sort.c
spinlock_debug.c	locking: Further name space cleanups	2009-12-14 23:55:33 +01:00
string.c	Add a strtobool function matching semantics of existing in kernel equivalents	2011-05-19 16:55:28 +09:30
string_helpers.c
swiotlb.c	swiotlb: Export swioltb_nr_tbl and utilize it as appropiate.	2011-06-06 15:41:16 -04:00
syscall.c
test-kstrtox.c	kstrtox: fix compile warnings in test	2011-04-14 16:06:54 -07:00
textsearch.c	textsearch: doc - fix spelling in lib/textsearch.c.	2011-01-24 23:33:30 -08:00
timerqueue.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
ts_bm.c
ts_fsm.c
ts_kmp.c
uuid.c	Unified UUID/GUID definition	2010-05-19 22:40:47 -04:00
vsprintf.c	vsprintf: Update %pI6c to not compress a single 0	2011-06-09 12:51:15 -07:00