android_kernel_samsung_msm8976/lib
David Howells b34df792b4 FS-Cache: Use radix tree preload correctly in tracking of pages to be stored
__fscache_write_page() attempts to load the radix tree preallocation pool for
the CPU it is on before calling radix_tree_insert(), as the insertion must be
done inside a pair of spinlocks.

Use of the preallocation pool, however, is contingent on the radix tree being
initialised without __GFP_WAIT specified.  __fscache_acquire_cookie() was
passing GFP_NOFS to INIT_RADIX_TREE() - but that includes __GFP_WAIT.

The solution is to AND out __GFP_WAIT.

Additionally, the banner comment to radix_tree_preload() is altered to make
note of this prerequisite.  Possibly there should be a WARN_ON() too.

Without this fix, I have seen the following recursive deadlock caused by
radix_tree_insert() attempting to allocate memory inside the spinlocked
region, which resulted in FS-Cache being called back into to release memory -
which required the spinlock already held.

=============================================
[ INFO: possible recursive locking detected ]
2.6.32-rc6-cachefs #24
---------------------------------------------
nfsiod/7916 is trying to acquire lock:
 (&cookie->lock){+.+.-.}, at: [<ffffffffa0076872>] __fscache_uncache_page+0xdb/0x160 [fscache]

but task is already holding lock:
 (&cookie->lock){+.+.-.}, at: [<ffffffffa0076acc>] __fscache_write_page+0x15c/0x3f3 [fscache]

other info that might help us debug this:
5 locks held by nfsiod/7916:
 #0:  (nfsiod){+.+.+.}, at: [<ffffffff81048290>] worker_thread+0x19a/0x2e2
 #1:  (&task->u.tk_work#2){+.+.+.}, at: [<ffffffff81048290>] worker_thread+0x19a/0x2e2
 #2:  (&cookie->lock){+.+.-.}, at: [<ffffffffa0076acc>] __fscache_write_page+0x15c/0x3f3 [fscache]
 #3:  (&object->lock#2){+.+.-.}, at: [<ffffffffa0076b07>] __fscache_write_page+0x197/0x3f3 [fscache]
 #4:  (&cookie->stores_lock){+.+...}, at: [<ffffffffa0076b0f>] __fscache_write_page+0x19f/0x3f3 [fscache]

stack backtrace:
Pid: 7916, comm: nfsiod Not tainted 2.6.32-rc6-cachefs #24
Call Trace:
 [<ffffffff8105ac7f>] __lock_acquire+0x1649/0x16e3
 [<ffffffff81059ded>] ? __lock_acquire+0x7b7/0x16e3
 [<ffffffff8100e27d>] ? dump_trace+0x248/0x257
 [<ffffffff8105ad70>] lock_acquire+0x57/0x6d
 [<ffffffffa0076872>] ? __fscache_uncache_page+0xdb/0x160 [fscache]
 [<ffffffff8135467c>] _spin_lock+0x2c/0x3b
 [<ffffffffa0076872>] ? __fscache_uncache_page+0xdb/0x160 [fscache]
 [<ffffffffa0076872>] __fscache_uncache_page+0xdb/0x160 [fscache]
 [<ffffffffa0077eb7>] ? __fscache_check_page_write+0x0/0x71 [fscache]
 [<ffffffffa00b4755>] nfs_fscache_release_page+0x86/0xc4 [nfs]
 [<ffffffffa00907f0>] nfs_release_page+0x3c/0x41 [nfs]
 [<ffffffff81087ffb>] try_to_release_page+0x32/0x3b
 [<ffffffff81092c2b>] shrink_page_list+0x316/0x4ac
 [<ffffffff81058a9b>] ? mark_held_locks+0x52/0x70
 [<ffffffff8135451b>] ? _spin_unlock_irq+0x2b/0x31
 [<ffffffff81093153>] shrink_inactive_list+0x392/0x67c
 [<ffffffff81058a9b>] ? mark_held_locks+0x52/0x70
 [<ffffffff810934ca>] shrink_list+0x8d/0x8f
 [<ffffffff81093744>] shrink_zone+0x278/0x33c
 [<ffffffff81052c70>] ? ktime_get_ts+0xad/0xba
 [<ffffffff8109453b>] try_to_free_pages+0x22e/0x392
 [<ffffffff8109184c>] ? isolate_pages_global+0x0/0x212
 [<ffffffff8108e16b>] __alloc_pages_nodemask+0x3dc/0x5cf
 [<ffffffff810ae24a>] cache_alloc_refill+0x34d/0x6c1
 [<ffffffff811bcf74>] ? radix_tree_node_alloc+0x52/0x5c
 [<ffffffff810ae929>] kmem_cache_alloc+0xb2/0x118
 [<ffffffff811bcf74>] radix_tree_node_alloc+0x52/0x5c
 [<ffffffff811bcfd5>] radix_tree_insert+0x57/0x19c
 [<ffffffffa0076b53>] __fscache_write_page+0x1e3/0x3f3 [fscache]
 [<ffffffffa00b4248>] __nfs_readpage_to_fscache+0x58/0x11e [nfs]
 [<ffffffffa009bb77>] nfs_readpage_release+0x34/0x9b [nfs]
 [<ffffffffa009c0d9>] nfs_readpage_release_full+0x32/0x4b [nfs]
 [<ffffffffa0006cff>] rpc_release_calldata+0x12/0x14 [sunrpc]
 [<ffffffffa0006e2d>] rpc_free_task+0x59/0x61 [sunrpc]
 [<ffffffffa0006f03>] rpc_async_release+0x10/0x12 [sunrpc]
 [<ffffffff810482e5>] worker_thread+0x1ef/0x2e2
 [<ffffffff81048290>] ? worker_thread+0x19a/0x2e2
 [<ffffffff81352433>] ? thread_return+0x3e/0x101
 [<ffffffffa0006ef3>] ? rpc_async_release+0x0/0x12 [sunrpc]
 [<ffffffff8104bff5>] ? autoremove_wake_function+0x0/0x34
 [<ffffffff81058d25>] ? trace_hardirqs_on+0xd/0xf
 [<ffffffff810480f6>] ? worker_thread+0x0/0x2e2
 [<ffffffff8104bd21>] kthread+0x7a/0x82
 [<ffffffff8100beda>] child_rip+0xa/0x20
 [<ffffffff8100b87c>] ? restore_args+0x0/0x30
 [<ffffffff8104c2b9>] ? add_wait_queue+0x15/0x44
 [<ffffffff8104bca7>] ? kthread+0x0/0x82
 [<ffffffff8100bed0>] ? child_rip+0x0/0x20

Signed-off-by: David Howells <dhowells@redhat.com>
2009-11-19 18:11:14 +00:00
..
lzo lzo: use get/put_unaligned_* helpers 2008-07-25 10:53:26 -07:00
reed_solomon
zlib_deflate trivial: fix typo "to to" in multiple files 2009-09-21 15:14:55 +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
atomic64.c lib: export generic atomic64_t functions 2009-07-29 19:10:35 -07:00
audit.c
bcd.c rtc: BCD codeshrink 2008-07-24 10:47:33 -07:00
bitmap.c Make bitmask 'and' operators return a result code 2009-08-21 09:26:15 -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
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
crc-ccitt.c
crc-itu-t.c
crc-t10dif.c [SCSI] lib: Add support for the T10 (SCSI) Data Integrity Field CRC 2008-07-12 08:22:32 -05:00
crc7.c
crc16.c
crc32.c
crc32defs.h
ctype.c
debug_locks.c lockdep: warn about lockdep disabling after kernel taint 2009-04-12 16:10:51 +02:00
debugobjects.c headers: remove sched.h from interrupt.h 2009-10-11 11:20:58 -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.c bzip2/lzma: don't stop search at first unconfigured compression 2009-02-19 13:36:55 -08:00
decompress_bunzip2.c lib/decompress_*: only include <linux/slab.h> if STATIC is not defined 2009-08-07 10:39:56 -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
devres.c
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 compile warning with PAE enabled 2009-10-29 16:25:50 +01:00
dump_stack.c
dynamic_debug.c Dynamic debug: fix typo: -/-> 2009-07-28 13:45:22 -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 missing kerneldoc annotations 2009-09-22 07:17:47 -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
idr.c cgroup: CSS ID support 2009-04-02 19:04:53 -07:00
inflate.c Nicolas Pitre has a new email address 2009-09-15 09:37:12 -07:00
int_sqrt.c
iomap.c Use WARN() in lib/ 2008-07-26 12:00:07 -07:00
iomap_copy.c
iommu-helper.c introduce generic iommu_num_pages function 2008-10-16 11:21:33 -07:00
ioremap.c
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
Kconfig lib: Provide generic atomic64_t implementation 2009-06-15 13:27:38 +10:00
Kconfig.debug powerpc: Minor cleanup to lib/Kconfig.debug 2009-10-27 16:42:42 +11:00
Kconfig.kgdb kgdb: remove the requirement for CONFIG_FRAME_POINTER 2008-08-01 08:39:34 -05:00
Kconfig.kmemcheck kmemcheck: depend on HAVE_ARCH_KMEMCHECK 2009-07-01 22:28:44 +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.c kobject: make kset_create check kobject_set_name return value 2009-06-15 21:30:24 -07:00
kobject_uevent.c driver core: allow non-root users to listen to uevents 2009-04-16 16:17:09 -07:00
kref.c
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: Remove __init from lmb_end_of_DRAM() 2009-08-27 12:25:26 -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
Makefile lib: flexible array implementation 2009-07-29 19:10:36 -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 FS-Cache: Use radix tree preload correctly in tracking of pages to be stored 2009-11-19 18:11:14 +00:00
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
rwsem.c
scatterlist.c lib/scatterlist: add a flags to signalize mapping direction 2009-07-31 12:28:45 +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
string.c strcmp: fix overflow and possibly signedness error 2009-11-18 17:18:13 -08:00
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
swiotlb.c lib/swiotlb.c: Fix strange panic message selection logic when swiotlb fills up 2009-08-21 10:36:03 +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 sscanf(): fix %*s%n 2009-10-01 16:11:16 -07:00