Tejun Heo e2852ae825 percpu_counter: add debugobj support ... All percpu counters are linked to a global list on initialization and removed from it on destruction. The list is walked during CPU up/down. If a percpu counter is freed without being properly destroyed, the system will oops only on the next CPU up/down making it pretty nasty to track down. This patch adds debugobj support for percpu counters so that such problems can be found easily. As percpu counters don't make sense on stack and can't be statically initialized, debugobj support is pretty simple. It's initialized and activated on counter initialization, and deactivatd and destroyed on counter destruction. With this patch applied, the bug fixed by commit 602586a83b (shmem: put_super must percpu_counter_destroy) triggers the following warning on tmpfs unmount and the system won't oops on the next cpu up/down operation. ------------[ cut here ]------------ WARNING: at lib/debugobjects.c:259 debug_print_object+0x5c/0x70() Hardware name: Bochs ODEBUG: free active (active state 0) object type: percpu_counter Modules linked in: Pid: 3999, comm: umount Not tainted 2.6.36-rc2-work+ #5 Call Trace: [<ffffffff81083f7f>] warn_slowpath_common+0x7f/0xc0 [<ffffffff81084076>] warn_slowpath_fmt+0x46/0x50 [<ffffffff813b45cc>] debug_print_object+0x5c/0x70 [<ffffffff813b50e5>] debug_check_no_obj_freed+0x125/0x210 [<ffffffff811577d3>] kfree+0xb3/0x2f0 [<ffffffff81132edd>] shmem_put_super+0x1d/0x30 [<ffffffff81162e96>] generic_shutdown_super+0x56/0xe0 [<ffffffff81162f86>] kill_anon_super+0x16/0x60 [<ffffffff81162ff7>] kill_litter_super+0x27/0x30 [<ffffffff81163295>] deactivate_locked_super+0x45/0x60 [<ffffffff81163cfa>] deactivate_super+0x4a/0x70 [<ffffffff8117d446>] mntput_no_expire+0x86/0xe0 [<ffffffff8117df7f>] sys_umount+0x6f/0x360 [<ffffffff8103f01b>] system_call_fastpath+0x16/0x1b ---[ end trace cce2a341ba3611a7 ]--- Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Thomas Gleixner <tglxlinutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2010-10-26 16:52:18 -07:00
..
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
zlib_deflate	trivial: fix typo "to to" in multiple files	2009-09-21 15:14:55 +02:00
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_test.c	ARM: 6213/1: atomic64_test: add ARM as supported architecture	2010-07-27 10:43:46 +01:00
atomic64.c	lib: Fix atomic64_add_unless return value convention	2010-03-01 11:38:46 -08:00
audit.c
bcd.c	rtc: BCD codeshrink	2008-07-24 10:47:33 -07:00
bitmap.c	lib/bitmap.c: use hex_to_bin()	2010-10-26 16:52:18 -07:00
bitrev.c
btree.c	lib/btree: fix possible NULL pointer dereference	2010-05-15 12:48:10 -07:00
bug.c	modules: Fix module_bug_list list corruption race	2010-10-05 11:29:27 -07:00
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
checksum.c	lib/checksum: fix one more thinko	2009-11-03 16:06:53 +01:00
cmdline.c	generic, memparse(): constify argument	2008-07-28 15:05:23 +02:00
cpu-notifier-error-inject.c	fault-injection: add CPU notifier error injection module	2010-05-27 09:12:48 -07:00
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
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
crc-ccitt.c
crc-itu-t.c
crc-t10dif.c
ctype.c	ctype: constify read-only _ctype string	2009-12-15 08:53:32 -08:00
debug_locks.c	rcu: Introduce lockdep-based checking to RCU read-side primitives	2010-02-25 09:40:59 +01:00
debugobjects.c	Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2010-05-18 08:17:58 -07:00
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	lib/decompress_bunzip2.c: fix checkstack warning	2010-08-11 08:59:23 -07:00
decompress_inflate.c	lzma/gzip: fix potential oops when input data is truncated	2009-09-24 07:21:05 -07:00
decompress_unlzma.c	lzma/gzip: fix potential oops when input data is truncated	2009-09-24 07:21:05 -07:00
decompress_unlzo.c	lib: fix the use of LZO to decompress initramfs images	2010-04-24 11:31:25 -07:00
decompress.c	Add LZO compression support for initramfs and old-style initrd	2010-01-11 09:34:05 -08:00
devres.c	lib/devres.c: fix comment typo	2010-07-11 22:16:32 +02:00
div64.c
dma-debug.c	llseek: automatically add .llseek fop	2010-10-15 15:53:27 +02:00
dump_stack.c
dynamic_debug.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6	2010-10-22 19:36:42 -07:00
extable.c	module: trim exception table on init free.	2009-06-12 21:47:04 +09:30
fault-inject.c	headers: remove sched.h from interrupt.h	2009-10-11 11:20:58 -07:00
find_last_bit.c	bitmap: find_last_bit()	2009-01-01 10:12:19 +10:30
find_next_bit.c
flex_array.c	flex_array: add helpers to get and put to make pointers easy to use	2010-08-09 20:45:09 -07:00
gcd.c	lib: add lib/gcd.c	2009-06-18 13:04:05 -07:00
gen_crc32table.c	crc32: major optimization	2010-05-25 08:07:06 -07:00
genalloc.c	genalloc: fix allocation from end of pool	2010-06-29 15:29:30 -07:00
halfmd4.c
hexdump.c	lib: introduce common method to convert hex digits	2010-05-25 08:07:05 -07:00
hweight.c	x86: Add optimized popcnt variants	2010-04-06 15:52:11 -07:00
idr.c	idr: fix idr_pre_get() locking description	2010-10-26 16:52:18 -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_copy.c
iomap.c	Use WARN() in lib/	2008-07-26 12:00:07 -07:00
iommu-helper.c	iommu: inline iommu_num_pages	2010-08-09 20:45:05 -07:00
ioremap.c	x86, ioremap: Fix incorrect physical address handling in PAE mode	2010-07-09 11:42:03 -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	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	Merge branch 'async' of macbook:git/btrfs-unstable	2010-08-09 10:36:44 +01:00
Kconfig.debug	percpu_counter: add debugobj support	2010-10-26 16:52:18 -07:00
Kconfig.kgdb	mips,kgdb: kdb low level trap catch and stack trace	2010-05-20 21:04:26 -05:00
Kconfig.kmemcheck	kmemcheck: depend on HAVE_ARCH_KMEMCHECK	2009-07-01 22:28:44 +02:00
kernel_lock.c	bkl: Fixup core_lock fallout	2009-12-14 23:55:33 +01:00
klist.c	driver core: Remove completion from struct klist_node	2009-01-06 10:44:30 -08:00
kobject_uevent.c	kobject_uevent: fix typo in comments	2010-08-23 18:12:46 -07:00
kobject.c	kobject: Introduce kset_find_obj_hinted.	2010-10-22 10:16:44 -07:00
kref.c	kref: remove kref_set	2010-05-21 09:37:29 -07:00
lcm.c	block: Fix overrun in lcm() and move it to lib	2010-03-15 12:47:59 +01:00
libcrc32c.c	libcrc32c: Fix "crc32c undefined" compilation error	2008-12-25 11:01:42 +11:00
list_debug.c	list debugging: warn when deleting a deleted entry	2010-08-09 20:45:08 -07:00
list_sort.c	lib/list_sort: do not pass bad pointers to cmp callback	2010-10-01 10:50:58 -07:00
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
lru_cache.c	The DRBD driver	2009-10-01 21:17:49 +02:00
Makefile	Merge branch 'async' of macbook:git/btrfs-unstable	2010-08-09 10:36:44 +01:00
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	parser: remove unnecessary strlen()	2009-12-15 08:53:33 -08:00
percpu_counter.c	percpu_counter: add debugobj support	2010-10-26 16:52:18 -07:00
plist.c	plist: Make plist debugging raw_spinlock aware	2009-12-14 23:55:33 +01:00
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	Merge branch 'rcu/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-2.6-rcu into core/rcu	2010-10-07 09:43:11 +02:00
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	rbtree: Undo augmented trees performance damage and regression	2010-07-05 14:43:50 +02:00
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: smaller wrappers around rwsem_down_failed_common	2010-08-09 20:45:11 -07:00
scatterlist.c	scatterlist: prevent invalid free when alloc fails	2010-08-30 19:55:09 +02:00
sha1.c
show_mem.c	mm: use the same log level for show_mem()	2010-03-06 11:26:27 -08:00
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	locking: Further name space cleanups	2009-12-14 23:55:33 +01:00
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	lib/string.c: simplify strnstr()	2010-03-06 11:26:35 -08:00
swiotlb.c	swiotlb: Use page alignment for early buffer allocation	2010-10-11 17:08:36 -04:00
syscall.c	task_current_syscall	2008-07-26 12:00:10 -07:00
textsearch.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
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	lib: fix scnprintf() if @size is == 0	2010-10-26 16:52:16 -07:00