aboutsummaryrefslogtreecommitdiff
path: root/lib
AgeCommit message (Collapse)Author
2012-10-31genalloc: stop crashing the system when destroying a poolThadeu Lima de Souza Cascardo
commit eedce141cd2dad8d0cefc5468ef41898949a7031 upstream. The genalloc code uses the bitmap API from include/linux/bitmap.h and lib/bitmap.c, which is based on long values. Both bitmap_set from lib/bitmap.c and bitmap_set_ll, which is the lockless version from genalloc.c, use BITMAP_LAST_WORD_MASK to set the first bits in a long in the bitmap. That one uses (1 << bits) - 1, 0b111, if you are setting the first three bits. This means that the API counts from the least significant bits (LSB from now on) to the MSB. The LSB in the first long is bit 0, then. The same works for the lookup functions. The genalloc code uses longs for the bitmap, as it should. In include/linux/genalloc.h, struct gen_pool_chunk has unsigned long bits[0] as its last member. When allocating the struct, genalloc should reserve enough space for the bitmap. This should be a proper number of longs that can fit the amount of bits in the bitmap. However, genalloc allocates an integer number of bytes that fit the amount of bits, but may not be an integer amount of longs. 9 bytes, for example, could be allocated for 70 bits. This is a problem in itself if the Least Significat Bit in a long is in the byte with the largest address, which happens in Big Endian machines. This means genalloc is not allocating the byte in which it will try to set or check for a bit. This may end up in memory corruption, where genalloc will try to set the bits it has not allocated. In fact, genalloc may not set these bits because it may find them already set, because they were not zeroed since they were not allocated. And that's what causes a BUG when gen_pool_destroy is called and check for any set bits. What really happens is that genalloc uses kmalloc_node with __GFP_ZERO on gen_pool_add_virt. With SLAB and SLUB, this means the whole slab will be cleared, not only the requested bytes. Since struct gen_pool_chunk has a size that is a multiple of 8, and slab sizes are multiples of 8, we get lucky and allocate and clear the right amount of bytes. Hower, this is not the case with SLOB or with older code that did memset after allocating instead of using __GFP_ZERO. So, a simple module as this (running 3.6.0), will cause a crash when rmmod'ed. [root@phantom-lp2 foo]# cat foo.c #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <linux/genalloc.h> MODULE_LICENSE("GPL"); MODULE_VERSION("0.1"); static struct gen_pool *foo_pool; static __init int foo_init(void) { int ret; foo_pool = gen_pool_create(10, -1); if (!foo_pool) return -ENOMEM; ret = gen_pool_add(foo_pool, 0xa0000000, 32 << 10, -1); if (ret) { gen_pool_destroy(foo_pool); return ret; } return 0; } static __exit void foo_exit(void) { gen_pool_destroy(foo_pool); } module_init(foo_init); module_exit(foo_exit); [root@phantom-lp2 foo]# zcat /proc/config.gz | grep SLOB CONFIG_SLOB=y [root@phantom-lp2 foo]# insmod ./foo.ko [root@phantom-lp2 foo]# rmmod foo ------------[ cut here ]------------ kernel BUG at lib/genalloc.c:243! cpu 0x4: Vector: 700 (Program Check) at [c0000000bb0e7960] pc: c0000000003cb50c: .gen_pool_destroy+0xac/0x110 lr: c0000000003cb4fc: .gen_pool_destroy+0x9c/0x110 sp: c0000000bb0e7be0 msr: 8000000000029032 current = 0xc0000000bb0e0000 paca = 0xc000000006d30e00 softe: 0 irq_happened: 0x01 pid = 13044, comm = rmmod kernel BUG at lib/genalloc.c:243! [c0000000bb0e7ca0] d000000004b00020 .foo_exit+0x20/0x38 [foo] [c0000000bb0e7d20] c0000000000dff98 .SyS_delete_module+0x1a8/0x290 [c0000000bb0e7e30] c0000000000097d4 syscall_exit+0x0/0x94 --- Exception: c00 (System Call) at 000000800753d1a0 SP (fffd0b0e640) is in userspace Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Benjamin Gaignard <benjamin.gaignard@stericsson.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-13lib/gcd.c: prevent possible div by 0Davidlohr Bueso
commit e96875677fb2b7cb739c5d7769824dff7260d31d upstream. Account for all properties when a and/or b are 0: gcd(0, 0) = 0 gcd(a, 0) = a gcd(0, b) = b Fixes no known problems in current kernels. Signed-off-by: Davidlohr Bueso <dave@gnu.org> Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-02digsig: add hash size comparision on signature verificationDmitry Kasatkin
commit bc01637a80f5b670bd70a0279d3f93fa8de1c96d upstream. When pkcs_1_v1_5_decode_emsa() returns without error and hash sizes do not match, hash comparision is not done and digsig_verify_rsa() returns no error. This is a bug and this patch fixes it. The bug was introduced in v3.3 by commit b35e286a640f ("lib/digsig: pkcs_1_v1_5_decode_emsa cleanup"). Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16bql: Avoid possible inconsistent calculation.Hiroaki SHIMODA
[ Upstream commit 914bec1011a25f65cdc94988a6f974bfb9a3c10d ] dql->num_queued could change while processing dql_completed(). To provide consistent calculation, added an on stack variable. Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com> Cc: Tom Herbert <therbert@google.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Denys Fedoryshchenko <denys@visp.net.lb> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16bql: Avoid unneeded limit decrement.Hiroaki SHIMODA
[ Upstream commit 25426b794efdc70dde7fd3134dc56fac3e7d562d ] When below pattern is observed, TIME dql_queued() dql_completed() | a) initial state | | b) X bytes queued V c) Y bytes queued d) X bytes completed e) Z bytes queued f) Y bytes completed a) dql->limit has already some value and there is no in-flight packet. b) X bytes queued. c) Y bytes queued and excess limit. d) X bytes completed and dql->prev_ovlimit is set and also dql->prev_num_queued is set Y. e) Z bytes queued. f) Y bytes completed. inprogress and prev_inprogress are true. At f), according to the comment, all_prev_completed becomes true and limit should be increased. But POSDIFF() ignores (completed == dql->prev_num_queued) case, so limit is decreased. Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com> Cc: Tom Herbert <therbert@google.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Denys Fedoryshchenko <denys@visp.net.lb> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16bql: Fix POSDIFF() to integer overflow aware.Hiroaki SHIMODA
[ Upstream commit 0cfd32b736ae0c36b42697584811042726c07cba ] POSDIFF() fails to take into account integer overflow case. Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com> Cc: Tom Herbert <therbert@google.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Denys Fedoryshchenko <denys@visp.net.lb> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-17btree: fix tree corruption in btree_get_prev()Roland Dreier
commit cbf8ae32f66a9ceb8907ad9e16663c2a29e48990 upstream. The memory the parameter __key points to is used as an iterator in btree_get_prev(), so if we save off a bkey() pointer in retry_key and then assign that to __key, we'll end up corrupting the btree internals when we do eg longcpy(__key, bkey(geo, node, i), geo->keylen); to return the key value. What we should do instead is use longcpy() to copy the key value that retry_key points to __key. This can cause a btree to get corrupted by seemingly read-only operations such as btree_for_each_safe. [akpm@linux-foundation.org: avoid the double longcpy()] Signed-off-by: Roland Dreier <roland@purestorage.com> Acked-by: Joern Engel <joern@logfs.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-10radix-tree: fix contiguous iteratorKonstantin Khlebnikov
commit fffaee365fded09f9ebf2db19066065fa54323c3 upstream. This patch fixes bug in macro radix_tree_for_each_contig(). If radix_tree_next_slot() sees NULL in next slot it returns NULL, but following radix_tree_next_chunk() switches iterating into next chunk. As result iterating becomes non-contiguous and breaks vfs "splice" and all its users. Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Reported-and-bisected-by: Hans de Bruin <jmdebruin@xmsnet.nl> Reported-and-bisected-by: Ondrej Zary <linux@rainbow-software.org> Reported-bisected-and-tested-by: Toralf Förster <toralf.foerster@gmx.de> Link: https://lkml.org/lkml/2012/6/5/64 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-18mpi: Avoid using freed pointer in mpi_lshift_limbs()Jesper Juhl
At the start of the function we assign 'a->d' to 'ap'. Then we use the RESIZE_IF_NEEDED macro on 'a' - this may free 'a->d' and replace it with newly allocaetd storage. In that case, we'll be operating on freed memory further down in the function when we index into 'ap[]'. Since we don't actually need 'ap' until after the use of the RESIZE_IF_NEEDED macro we can just delay the assignment to it until after we've potentially resized, thus avoiding the issue. While I was there anyway I also changed the integer variable 'n' to be const. It might as well be since we only assign to it once and use it as a constant, and then the compiler will tell us if we ever assign to it in the future. Signed-off-by: Jesper Juhl <jj@chaosbits.net> Acked-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-04-10kobject: provide more diagnostic info for kobject_add_internal() failuresDan Williams
1/ convert open-coded KERN_ERR+dump_stack() to WARN(), so that automated tools pick up this warning. 2/ include the 'child' and 'parent' kobject names. This information was useful for tracking down the case where scsi invoked device_del() on a parent object and subsequently invoked device_add() on a child. Now the warning looks like: kobject_add_internal failed for target8:0:16 (error: -2 parent: end_device-8:0:24) Pid: 2942, comm: scsi_scan_8 Not tainted 3.3.0-rc7-isci+ #2 Call Trace: [<ffffffff8125e551>] kobject_add_internal+0x1c1/0x1f3 [<ffffffff81075149>] ? trace_hardirqs_on+0xd/0xf [<ffffffff8125e659>] kobject_add_varg+0x41/0x50 [<ffffffff8125e723>] kobject_add+0x64/0x66 [<ffffffff8131124b>] device_add+0x12d/0x63a [<ffffffff8125e0ef>] ? kobject_put+0x4c/0x50 [<ffffffff8132f370>] scsi_sysfs_add_sdev+0x4e/0x28a [<ffffffff8132dce3>] do_scan_async+0x9c/0x145 Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: James Bottomley <JBottomley@parallels.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-29Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 updates from Ingo Molnar. This touches some non-x86 files due to the sanitized INLINE_SPIN_UNLOCK config usage. Fixed up trivial conflicts due to just header include changes (removing headers due to cpu_idle() merge clashing with the <asm/system.h> split). * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic/amd: Be more verbose about LVT offset assignments x86, tls: Off by one limit check x86/ioapic: Add io_apic_ops driver layer to allow interception x86/olpc: Add debugfs interface for EC commands x86: Merge the x86_32 and x86_64 cpu_idle() functions x86/kconfig: Remove CONFIG_TR=y from the defconfigs x86: Stop recursive fault in print_context_stack after stack overflow x86/io_apic: Move and reenable irq only when CONFIG_GENERIC_PENDING_IRQ=y x86/apic: Add separate apic_id_valid() functions for selected apic drivers locking/kconfig: Simplify INLINE_SPIN_UNLOCK usage x86/kconfig: Update defconfigs x86: Fix excessive MSR print out when show_msr is not specified
2012-03-28Merge branch 'akpm' (Andrew's patch-bomb)Linus Torvalds
Merge third batch of patches from Andrew Morton: - Some MM stragglers - core SMP library cleanups (on_each_cpu_mask) - Some IPI optimisations - kexec - kdump - IPMI - the radix-tree iterator work - various other misc bits. "That'll do for -rc1. I still have ~10 patches for 3.4, will send those along when they've baked a little more." * emailed from Andrew Morton <akpm@linux-foundation.org>: (35 commits) backlight: fix typo in tosa_lcd.c crc32: add help text for the algorithm select option mm: move hugepage test examples to tools/testing/selftests/vm mm: move slabinfo.c to tools/vm mm: move page-types.c from Documentation to tools/vm selftests/Makefile: make `run_tests' depend on `all' selftests: launch individual selftests from the main Makefile radix-tree: use iterators in find_get_pages* functions radix-tree: rewrite gang lookup using iterator radix-tree: introduce bit-optimized iterator fs/proc/namespaces.c: prevent crash when ns_entries[] is empty nbd: rename the nbd_device variable from lo to nbd pidns: add reboot_pid_ns() to handle the reboot syscall sysctl: use bitmap library functions ipmi: use locks on watchdog timeout set on reboot ipmi: simplify locking ipmi: fix message handling during panics ipmi: use a tasklet for handling received messages ipmi: increase KCS timeouts ipmi: decrease the IPMI message transaction time in interrupt mode ...
2012-03-28crc32: add help text for the algorithm select optionDarrick J. Wong
Add help text to the crc32 algorithm selection option in Kconfig. Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Reported-by: Stefan Richter <stefanr@s5r6.in-berlin.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-28radix-tree: rewrite gang lookup using iteratorKonstantin Khlebnikov
Rewrite radix_tree_gang_lookup_* functions using the new radix-tree iterator. Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Tested-by: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-28radix-tree: introduce bit-optimized iteratorKonstantin Khlebnikov
A series of radix tree cleanups, and usage of them in the core pagecache code. Micro-benchmark: lookup 14 slots (typical page-vector size) in radix-tree there earch <step> slot filled and tagged before/after - nsec per full scan through tree * Intel Sandy Bridge i7-2620M 4Mb L3 New code always faster * AMD Athlon 6000+ 2x1Mb L2, without L3 New code generally faster, Minor degradation (marked with "*") for huge sparse trees * i386 on Sandy Bridge New code faster for common cases: tagged and dense trees. Some degradations for non-tagged lookup on sparse trees. Ideally, there might help __ffs() analog for searching first non-zero long element in array, gcc sometimes cannot optimize this loop corretly. Numbers: CPU: Intel Sandy Bridge i7-2620M 4Mb L3 radix-tree with 1024 slots: tagged lookup step 1 before 7156 after 3613 step 2 before 5399 after 2696 step 3 before 4779 after 1928 step 4 before 4456 after 1429 step 5 before 4292 after 1213 step 6 before 4183 after 1052 step 7 before 4157 after 951 step 8 before 4016 after 812 step 9 before 3952 after 851 step 10 before 3937 after 732 step 11 before 4023 after 709 step 12 before 3872 after 657 step 13 before 3892 after 633 step 14 before 3720 after 591 step 15 before 3879 after 578 step 16 before 3561 after 513 normal lookup step 1 before 4266 after 3301 step 2 before 2695 after 2129 step 3 before 2083 after 1712 step 4 before 1801 after 1534 step 5 before 1628 after 1313 step 6 before 1551 after 1263 step 7 before 1475 after 1185 step 8 before 1432 after 1167 step 9 before 1373 after 1092 step 10 before 1339 after 1134 step 11 before 1292 after 1056 step 12 before 1319 after 1030 step 13 before 1276 after 1004 step 14 before 1256 after 987 step 15 before 1228 after 992 step 16 before 1247 after 999 radix-tree with 1024*1024*128 slots: tagged lookup step 1 before 1086102841 after 674196409 step 2 before 816839155 after 498138306 step 7 before 599728907 after 240676762 step 15 before 555729253 after 185219677 step 63 before 606637748 after 128585664 step 64 before 608384432 after 102945089 step 65 before 596987114 after 123996019 step 128 before 304459225 after 56783056 step 256 before 158846855 after 31232481 step 512 before 86085652 after 18950595 step 12345 before 6517189 after 1674057 normal lookup step 1 before 626064869 after 544418266 step 2 before 418809975 after 336321473 step 7 before 242303598 after 207755560 step 15 before 208380563 after 176496355 step 63 before 186854206 after 167283638 step 64 before 176188060 after 170143976 step 65 before 185139608 after 167487116 step 128 before 88181865 after 86913490 step 256 before 45733628 after 45143534 step 512 before 24506038 after 23859036 step 12345 before 2177425 after 2018662 * AMD Athlon 6000+ 2x1Mb L2, without L3 radix-tree with 1024 slots: tag-lookup step 1 before 8164 after 5379 step 2 before 5818 after 5581 step 3 before 4959 after 4213 step 4 before 4371 after 3386 step 5 before 4204 after 2997 step 6 before 4950 after 2744 step 7 before 4598 after 2480 step 8 before 4251 after 2288 step 9 before 4262 after 2243 step 10 before 4175 after 2131 step 11 before 3999 after 2024 step 12 before 3979 after 1994 step 13 before 3842 after 1929 step 14 before 3750 after 1810 step 15 before 3735 after 1810 step 16 before 3532 after 1660 normal-lookup step 1 before 7875 after 5847 step 2 before 4808 after 4071 step 3 before 4073 after 3462 step 4 before 3677 after 3074 step 5 before 4308 after 2978 step 6 before 3911 after 3807 step 7 before 3635 after 3522 step 8 before 3313 after 3202 step 9 before 3280 after 3257 step 10 before 3166 after 3083 step 11 before 3066 after 3026 step 12 before 2985 after 2982 step 13 before 2925 after 2924 step 14 before 2834 after 2808 step 15 before 2805 after 2803 step 16 before 2647 after 2622 radix-tree with 1024*1024*128 slots: tag-lookup step 1 before 1288059720 after 951736580 step 2 before 961292300 after 884212140 step 7 before 768905140 after 547267580 step 15 before 771319480 after 456550640 step 63 before 504847640 after 242704304 step 64 before 392484800 after 177920786 step 65 before 491162160 after 246895264 step 128 before 208084064 after 97348392 step 256 before 112401035 after 51408126 step 512 before 75825834 after 29145070 step 12345 before 5603166 after 2847330 normal-lookup step 1 before 1025677120 after 861375100 step 2 before 647220080 after 572258540 step 7 before 505518960 after 484041813 step 15 before 430483053 after 444815320 * step 63 before 388113453 after 404250546 * step 64 before 374154666 after 396027440 * step 65 before 381423973 after 396704853 * step 128 before 190078700 after 202619384 * step 256 before 100886756 after 102829108 * step 512 before 64074505 after 56158720 step 12345 before 4237289 after 4422299 * * i686 on Sandy bridge radix-tree with 1024 slots: tagged lookup step 1 before 7990 after 4019 step 2 before 5698 after 2897 step 3 before 5013 after 2475 step 4 before 4630 after 1721 step 5 before 4346 after 1759 step 6 before 4299 after 1556 step 7 before 4098 after 1513 step 8 before 4115 after 1222 step 9 before 3983 after 1390 step 10 before 4077 after 1207 step 11 before 3921 after 1231 step 12 before 3894 after 1116 step 13 before 3840 after 1147 step 14 before 3799 after 1090 step 15 before 3797 after 1059 step 16 before 3783 after 745 normal lookup step 1 before 5103 after 3499 step 2 before 3299 after 2550 step 3 before 2489 after 2370 step 4 before 2034 after 2302 * step 5 before 1846 after 2268 * step 6 before 1752 after 2249 * step 7 before 1679 after 2164 * step 8 before 1627 after 2153 * step 9 before 1542 after 2095 * step 10 before 1479 after 2109 * step 11 before 1469 after 2009 * step 12 before 1445 after 2039 * step 13 before 1411 after 2013 * step 14 before 1374 after 2046 * step 15 before 1340 after 1975 * step 16 before 1331 after 2000 * radix-tree with 1024*1024*128 slots: tagged lookup step 1 before 1225865377 after 667153553 step 2 before 842427423 after 471533007 step 7 before 609296153 after 276260116 step 15 before 544232060 after 226859105 step 63 before 519209199 after 141343043 step 64 before 588980279 after 141951339 step 65 before 521099710 after 138282060 step 128 before 298476778 after 83390628 step 256 before 149358342 after 43602609 step 512 before 76994713 after 22911077 step 12345 before 5328666 after 1472111 normal lookup step 1 before 819284564 after 533635310 step 2 before 512421605 after 364956155 step 7 before 271443305 after 305721345 * step 15 before 223591630 after 273960216 * step 63 before 190320247 after 217770207 * step 64 before 178538168 after 267411372 * step 65 before 186400423 after 215347937 * step 128 before 88106045 after 140540612 * step 256 before 44812420 after 70660377 * step 512 before 24435438 after 36328275 * step 12345 before 2123924 after 2148062 * bloat-o-meter delta for this patchset + patchset with related shmem cleanups bloat-o-meter: x86_64 add/remove: 4/3 grow/shrink: 5/6 up/down: 928/-939 (-11) function old new delta radix_tree_next_chunk - 499 +499 shmem_unuse 428 554 +126 shmem_radix_tree_replace 131 227 +96 find_get_pages_tag 354 419 +65 find_get_pages_contig 345 407 +62 find_get_pages 362 396 +34 __kstrtab_radix_tree_next_chunk - 22 +22 __ksymtab_radix_tree_next_chunk - 16 +16 __kcrctab_radix_tree_next_chunk - 8 +8 radix_tree_gang_lookup_slot 204 203 -1 static.shmem_xattr_set 384 381 -3 radix_tree_gang_lookup_tag_slot 208 191 -17 radix_tree_gang_lookup 231 187 -44 radix_tree_gang_lookup_tag 247 199 -48 shmem_unlock_mapping 278 190 -88 __lookup 217 - -217 __lookup_tag 242 - -242 radix_tree_locate_item 279 - -279 bloat-o-meter: i386 add/remove: 3/3 grow/shrink: 8/9 up/down: 1075/-1275 (-200) function old new delta radix_tree_next_chunk - 757 +757 shmem_unuse 352 449 +97 find_get_pages_contig 269 322 +53 shmem_radix_tree_replace 113 154 +41 find_get_pages_tag 277 318 +41 dcache_dir_lseek 426 458 +32 __kstrtab_radix_tree_next_chunk - 22 +22 vc_do_resize 968 977 +9 snd_pcm_lib_read1 725 733 +8 __ksymtab_radix_tree_next_chunk - 8 +8 netlbl_cipsov4_list 1120 1127 +7 find_get_pages 293 291 -2 new_slab 467 459 -8 bitfill_unaligned_rev 425 417 -8 radix_tree_gang_lookup_tag_slot 177 146 -31 blk_dump_cmd 267 229 -38 radix_tree_gang_lookup_slot 212 134 -78 shmem_unlock_mapping 221 128 -93 radix_tree_gang_lookup_tag 275 162 -113 radix_tree_gang_lookup 255 126 -129 __lookup 227 - -227 __lookup_tag 271 - -271 radix_tree_locate_item 277 - -277 This patch: Implement a clean, simple and effective radix-tree iteration routine. Iterating divided into two phases: * lookup next chunk in radix-tree leaf node * iterating through slots in this chunk Main iterator function radix_tree_next_chunk() returns pointer to first slot, and stores in the struct radix_tree_iter index of next-to-last slot. For tagged-iterating it also constuct bitmask of tags for retunted chunk. All additional logic implemented as static-inline functions and macroses. Also adds radix_tree_find_next_bit() static-inline variant of find_next_bit() optimized for small constant size arrays, because find_next_bit() too heavy for searching in an array with one/two long elements. [akpm@linux-foundation.org: rework comments a bit] Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Tested-by: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-28lib/cpumask.c: remove __any_online_cpu()Srivatsa S. Bhat
__any_online_cpu() is not optimal and also unnecessary. So, replace its use by faster cpumask_* operations. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Venkatesh Pallipadi <venki@google.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-28Merge tag 'split-asm_system_h-for-linus-20120328' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system Pull "Disintegrate and delete asm/system.h" from David Howells: "Here are a bunch of patches to disintegrate asm/system.h into a set of separate bits to relieve the problem of circular inclusion dependencies. I've built all the working defconfigs from all the arches that I can and made sure that they don't break. The reason for these patches is that I recently encountered a circular dependency problem that came about when I produced some patches to optimise get_order() by rewriting it to use ilog2(). This uses bitops - and on the SH arch asm/bitops.h drags in asm-generic/get_order.h by a circuituous route involving asm/system.h. The main difficulty seems to be asm/system.h. It holds a number of low level bits with no/few dependencies that are commonly used (eg. memory barriers) and a number of bits with more dependencies that aren't used in many places (eg. switch_to()). These patches break asm/system.h up into the following core pieces: (1) asm/barrier.h Move memory barriers here. This already done for MIPS and Alpha. (2) asm/switch_to.h Move switch_to() and related stuff here. (3) asm/exec.h Move arch_align_stack() here. Other process execution related bits could perhaps go here from asm/processor.h. (4) asm/cmpxchg.h Move xchg() and cmpxchg() here as they're full word atomic ops and frequently used by atomic_xchg() and atomic_cmpxchg(). (5) asm/bug.h Move die() and related bits. (6) asm/auxvec.h Move AT_VECTOR_SIZE_ARCH here. Other arch headers are created as needed on a per-arch basis." Fixed up some conflicts from other header file cleanups and moving code around that has happened in the meantime, so David's testing is somewhat weakened by that. We'll find out anything that got broken and fix it.. * tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system: (38 commits) Delete all instances of asm/system.h Remove all #inclusions of asm/system.h Add #includes needed to permit the removal of asm/system.h Move all declarations of free_initmem() to linux/mm.h Disintegrate asm/system.h for OpenRISC Split arch_align_stack() out from asm-generic/system.h Split the switch_to() wrapper out of asm-generic/system.h Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h Create asm-generic/barrier.h Make asm-generic/cmpxchg.h #include asm-generic/cmpxchg-local.h Disintegrate asm/system.h for Xtensa Disintegrate asm/system.h for Unicore32 [based on ver #3, changed by gxt] Disintegrate asm/system.h for Tile Disintegrate asm/system.h for Sparc Disintegrate asm/system.h for SH Disintegrate asm/system.h for Score Disintegrate asm/system.h for S390 Disintegrate asm/system.h for PowerPC Disintegrate asm/system.h for PA-RISC Disintegrate asm/system.h for MN10300 ...
2012-03-28Remove all #inclusions of asm/system.hDavid Howells
Remove all #inclusions of asm/system.h preparatory to splitting and killing it. Performed with the following command: perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *` Signed-off-by: David Howells <dhowells@redhat.com>
2012-03-28Disintegrate asm/system.h for PowerPCDavid Howells
Disintegrate asm/system.h for PowerPC. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> cc: linuxppc-dev@lists.ozlabs.org
2012-03-27Merge branch 'for-linus-3.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml Pull UML changes from Richard Weinberger: "Mostly bug fixes and cleanups" * 'for-linus-3.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: (35 commits) um: Update defconfig um: Switch to large mcmodel on x86_64 MTD: Relax dependencies um: Wire CONFIG_GENERIC_IO up um: Serve io_remap_pfn_range() Introduce CONFIG_GENERIC_IO um: allow SUBARCH=x86 um: most of the SUBARCH uses can be killed um: deadlock in line_write_interrupt() um: don't bother trying to rebuild CHECKFLAGS for USER_OBJS um: use the right ifdef around exports in user_syms.c um: a bunch of headers can be killed by using generic-y um: ptrace-generic.h doesn't need user.h um: kill HOST_TASK_PID um: remove pointless include of asm/fixmap.h from asm/pgtable.h um: asm-offsets.h might as well come from underlying arch... um: merge processor_{32,64}.h a bit... um: switch close_chan() to struct line um: race fix: initialize delayed_work *before* registering IRQ um: line->have_irq is never checked... ...
2012-03-25Introduce CONFIG_GENERIC_IORichard Weinberger
There are situations where CONFIG_HAS_IOMEM is too restrictive. For example CONFIG_MTD_NAND_NANDSIM depends on CONFIG_HAS_IOMEM but it works perfectly fine if an architecture without io memory just includes asm-generic/io.h or implements everything defined in it. UML is such a corner case. Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-24Merge tag 'module-for-3.4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux Pull cleanup of fs/ and lib/ users of module.h from Paul Gortmaker: "Fix up files in fs/ and lib/ dirs to only use module.h if they really need it. These are trivial in scope vs the work done previously. We now have things where any few remaining cleanups can be farmed out to arch or subsystem maintainers, and I have done so when possible. What is remaining here represents the bits that don't clearly lie within a single arch/subsystem boundary, like the fs dir and the lib dir. Some duplicate includes arising from overlapping fixes from independent subsystem maintainer submissions are also quashed." Fix up trivial conflicts due to clashes with other include file cleanups (including some due to the previous bug.h cleanup pull). * tag 'module-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: lib: reduce the use of module.h wherever possible fs: reduce the use of module.h wherever possible includecheck: delete any duplicate instances of module.h
2012-03-24Merge tag 'bug-for-3.4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux Pull <linux/bug.h> cleanup from Paul Gortmaker: "The changes shown here are to unify linux's BUG support under the one <linux/bug.h> file. Due to historical reasons, we have some BUG code in bug.h and some in kernel.h -- i.e. the support for BUILD_BUG in linux/kernel.h predates the addition of linux/bug.h, but old code in kernel.h wasn't moved to bug.h at that time. As a band-aid, kernel.h was including <asm/bug.h> to pseudo link them. This has caused confusion[1] and general yuck/WTF[2] reactions. Here is an example that violates the principle of least surprise: CC lib/string.o lib/string.c: In function 'strlcat': lib/string.c:225:2: error: implicit declaration of function 'BUILD_BUG_ON' make[2]: *** [lib/string.o] Error 1 $ $ grep linux/bug.h lib/string.c #include <linux/bug.h> $ We've included <linux/bug.h> for the BUG infrastructure and yet we still get a compile fail! [We've not kernel.h for BUILD_BUG_ON.] Ugh - very confusing for someone who is new to kernel development. With the above in mind, the goals of this changeset are: 1) find and fix any include/*.h files that were relying on the implicit presence of BUG code. 2) find and fix any C files that were consuming kernel.h and hence relying on implicitly getting some/all BUG code. 3) Move the BUG related code living in kernel.h to <linux/bug.h> 4) remove the asm/bug.h from kernel.h to finally break the chain. During development, the order was more like 3-4, build-test, 1-2. But to ensure that git history for bisect doesn't get needless build failures introduced, the commits have been reorderd to fix the problem areas in advance. [1] https://lkml.org/lkml/2012/1/3/90 [2] https://lkml.org/lkml/2012/1/17/414" Fix up conflicts (new radeon file, reiserfs header cleanups) as per Paul and linux-next. * tag 'bug-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: kernel.h: doesn't explicitly use bug.h, so don't include it. bug: consolidate BUILD_BUG_ON with other bug code BUG: headers with BUG/BUG_ON etc. need linux/bug.h bug.h: add include of it to various implicit C users lib: fix implicit users of kernel.h for TAINT_WARN spinlock: macroize assert_spin_locked to avoid bug.h dependency x86: relocate get/set debugreg fcns to include/asm/debugreg.
2012-03-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctlLinus Torvalds
Pull sysctl updates from Eric Biederman: - Rewrite of sysctl for speed and clarity. Insert/remove/Lookup in sysctl are all now O(NlogN) operations, and are no longer bottlenecks in the process of adding and removing network devices. sysctl is now focused on being a filesystem instead of system call and the code can all be found in fs/proc/proc_sysctl.c. Hopefully this means the code is now approachable. Much thanks is owed to Lucian Grinjincu for keeping at this until something was found that was usable. - The recent proc_sys_poll oops found by the fuzzer during hibernation is fixed. * git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctl: (36 commits) sysctl: protect poll() in entries that may go away sysctl: Don't call sysctl_follow_link unless we are a link. sysctl: Comments to make the code clearer. sysctl: Correct error return from get_subdir sysctl: An easier to read version of find_subdir sysctl: fix memset parameters in setup_sysctl_set() sysctl: remove an unused variable sysctl: Add register_sysctl for normal sysctl users sysctl: Index sysctl directories with rbtrees. sysctl: Make the header lists per directory. sysctl: Move sysctl_check_dups into insert_header sysctl: Modify __register_sysctl_paths to take a set instead of a root and an nsproxy sysctl: Replace root_list with links between sysctl_table_sets. sysctl: Add sysctl_print_dir and use it in get_subdir sysctl: Stop requiring explicit management of sysctl directories sysctl: Add a root pointer to ctl_table_set sysctl: Rewrite proc_sys_readdir in terms of first_entry and next_entry sysctl: Rewrite proc_sys_lookup introducing find_entry and lookup_entry. sysctl: Normalize the root_table data structure. sysctl: Factor out insert_header and erase_header ...
2012-03-23procfs: add num_to_str() to speed up /proc/statKAMEZAWA Hiroyuki
== stat_check.py num = 0 with open("/proc/stat") as f: while num < 1000 : data = f.read() f.seek(0, 0) num = num + 1 == perf shows 20.39% stat_check.py [kernel.kallsyms] [k] format_decode 13.41% stat_check.py [kernel.kallsyms] [k] number 12.61% stat_check.py [kernel.kallsyms] [k] vsnprintf 10.85% stat_check.py [kernel.kallsyms] [k] memcpy 4.85% stat_check.py [kernel.kallsyms] [k] radix_tree_lookup 4.43% stat_check.py [kernel.kallsyms] [k] seq_printf This patch removes most of calls to vsnprintf() by adding num_to_str() and seq_print_decimal_ull(), which prints decimal numbers without rich functions provided by printf(). On my 8cpu box. == Before patch == [root@bluextal test]# time ./stat_check.py real 0m0.150s user 0m0.026s sys 0m0.121s == After patch == [root@bluextal test]# time ./stat_check.py real 0m0.055s user 0m0.022s sys 0m0.030s [akpm@linux-foundation.org: remove incorrect comment, use less statck in num_to_str(), move comment from .h to .c, simplify seq_put_decimal_ull()] [andrea@betterlinux.com: avoid breaking the ABI in /proc/stat] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrea Righi <andrea@betterlinux.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Glauber Costa <glommer@parallels.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Turner <pjt@google.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: select an algorithm via KconfigDarrick J. Wong
Allow the kernel builder to choose a crc32* algorithm for the kernel. Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Cc: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: add self-test code for crc32cDarrick J. Wong
Add self-test code for crc32c. Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Cc: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: bolt on crc32cDarrick J. Wong
Reuse the existing crc32 code to stamp out a crc32c implementation. Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Bob Pearson <rpearson@systemfabricworks.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: add note about this patchset to crc32.cBob Pearson
Add a comment at the top of crc32.c [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: optimize loop counter for x86Bob Pearson
Add two changes that improve the performance of x86 systems 1. replace main loop with incrementing counter this change improves the performance of the selftest by about 5-6% on Nehalem CPUs. The apparent reason is that the compiler can use the loop index to perform an indexed memory access. This is reported to make the performance of PowerPC CPUs to get worse. 2. replace the rem_len loop with incrementing counter this change improves the performance of the selftest, which has more than the usual number of occurances, by about 1-2% on x86 CPUs. In actual work loads the length is most often a multiple of 4 bytes and this code does not get executed as often if at all. Again this change is reported to make the performance of PowerPC get worse. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: add slice-by-8 algorithm to existing codeBob Pearson
Add slicing-by-8 algorithm to the existing slicing-by-4 algorithm. This consists of: - extend largest BITS size from 32 to 64 - extend tables from tab[4][256] to up to tab[8][256] - Add code for inner loop. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: make CRC_*_BITS definition correspond to actual bit countsBob Pearson
crc32.c provides a choice of one of several algorithms for computing the LSB and LSB versions of the CRC32 checksum based on the parameters CRC_LE_BITS and CRC_BE_BITS. In the original version the values 1, 2, 4 and 8 respectively selected versions of the alrogithm that computed the crc 1, 2, 4 and 32 bits as a time. This patch series adds a new version that computes the CRC 64 bits at a time. To make things easier to understand the parameter has been reinterpreted to actually stand for the number of bits processed in each step of the algorithm so that the old value 8 has been replaced with the value 32. This also allows us to add in a widely used crc algorithm that computes the crc 8 bits at a time called the Sarwate algorithm. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: fix mixing of endian-specific typesBob Pearson
crc32.c in its original version freely mixed u32, __le32 and __be32 types which caused warnings from sparse with __CHECK_ENDIAN__. This patch fixes these by forcing the types to u32. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: miscellaneous cleanupsBob Pearson
Misc cleanup of lib/crc32.c and related files. - remove unnecessary header files. - straighten out some convoluted ifdef's - rewrite some references to 2 dimensional arrays as 1 dimensional arrays to make them correct. I.e. replace tab[i] with tab[0][i]. - a few trivial whitespace changes - fix a warning in gen_crc32tables.c caused by a mismatch in the type of the pointer passed to output table. Since the table is only used at kernel compile time, it is simpler to make the table big enough to hold the largest column size used. One cannot make the column size smaller in output_table because it has to be used by both the le and be tables and they can have different column sizes. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: simplify unit test codeBob Pearson
Replace the unit test provided in crc32.c, which doesn't have a makefile and doesn't compile with current headers, with a simpler self test routine that also gives a measure of performance and runs at module init time. The self test option can be enabled through a configuration option CONFIG_CRC32_SELFTEST. The test stresses the pre and post loops and is thus not very realistic since actual uses will likely have addresses and lengths that are at least 4 byte aligned. However, the main loop is long enough so that the performance is dominated by that loop. The expected values for crc32_le and crc32_be were generated with the original version of crc32.c using CRC_BITS_LE = 8 and CRC_BITS_BE = 8. These values were then used to check all the values of the BITS parameters in both the original and new versions. The performance results show some variability from run to run in spite of attempts to both warm the cache and reduce the amount of OS noise by limiting interrutps during the test. To get comparable results and to analyse options wrt performance the best time reported over a small sample of runs has been taken. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: move long comment about crc32 fundamentals to Documentation/Bob Pearson
Move a long comment from lib/crc32.c to Documentation/crc32.txt where it will more likely get read. Edited the resulting document to add an explanation of the slicing-by-n algorithm. [djwong@us.ibm.com: minor changelog tweaks] [akpm@linux-foundation.org: fix typo, per George] Signed-off-by: George Spelvin <linux@horizon.com> Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: remove two instances of trailing whitespacesBob Pearson
This patchset (re)uses Bob Pearson's crc32 slice-by-8 code to stamp out a software crc32c implementation. It removes the crc32c implementation in crypto/ in favor of using the stamped-out one in lib/. There is also a change to Kconfig so that the kernel builder can pick an implementation best suited for the hardware. The motivation for this patchset is that I am working on adding full metadata checksumming to ext4. As far as performance impact of adding checksumming goes, I see nearly no change with a standard mail server ffsb simulation. On a test that involves only file creation and deletion and extent tree writes, I see a drop of about 50 pcercent with the current kernel crc32c implementation; this improves to a drop of about 20 percent with the enclosed crc32c code. When metadata is usually a small fraction of total IO, this new implementation doesn't help much because metadata is usually a small fraction of total IO. However, when we are doing IO that is almost all metadata (such as rm -rf'ing a tree), then this patch speeds up the operation substantially. Incidentally, given that iscsi, sctp, and btrfs also use crc32c, this patchset should improve their speed as well. I have not yet quantified that, however. This latest submission combines Bob's patches from late August 2011 with mine so that they can be one coherent patch set. Please excuse my inability to combine some of the patches; I've been advised to leave Bob's patches alone and build atop them instead. :/ Since the last posting, I've also collected some crc32c test results on a bunch of different x86/powerpc/sparc platforms. The results can be viewed here: http://goo.gl/sgt3i ; the "crc32-kern-le" and "crc32c" columns describe the performance of the kernel's current crc32 and crc32c software implementations. The "crc32c-by8-le" column shows crc32c performance with this patchset applied. I expect crc32 performance to be roughly the same. The two _boost columns at the right side of the spreadsheet shows how much faster the new implementation is over the old one. As you can see, crc32 rises substantially, and crc32c experiences a huge increase. This patch: - remove trailing whitespace from lib/crc32.c - remove trailing whitespace from lib/crc32defs.h [djwong@us.ibm.com: changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23prio_tree: introduce prio_set_parent()Xiao Guangrong
Introduce prio_set_parent() to abstract the operation which is used to attach the node to its parent. Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23prio_tree: simplify prio_tree_expand()Xiao Guangrong
In current code, the deleted-node is recorded from first to last, actually, we can directly attach these node on 'node' we will insert as the left child, it can let the code more readable. Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23prio_tree: cleanup prio_tree_left()/prio_tree_right()Xiao Guangrong
Introduce iter_walk_down()/iter_walk_up() to remove the common code between prio_tree_left() and prio_tree_right(). Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23prio_tree: remove unnecessary code in prio_tree_replaceXiao Guangrong
Remove the code since 'node' has already been initialized in the begin of the function Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23string: memchr_inv() speed improvementsAkinobu Mita
- Generate a 64-bit pattern more efficiently memchr_inv needs to generate a 64-bit pattern filled with a target character. The operation can be done by more efficient way. - Don't call the slow check_bytes() if the memory area is 64-bit aligned memchr_inv compares contiguous 64-bit words with the 64-bit pattern as much as possible. The outside of the region is checked by check_bytes() that scans for each byte. Unfortunately, the first 64-bit word is unexpectedly scanned by check_bytes() even if the memory area is aligned to a 64-bit boundary. Both changes were originally suggested by Eric Dumazet. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23nmi watchdog: do not use cpp symbol in KconfigCong Wang
ARCH_HAS_NMI_WATCHDOG is a macro defined by arch, but config HARDLOCKUP_DETECTOR depends on it. This is wrong, ARCH_HAS_NMI_WATCHDOG has to be a Kconfig config, and arch's need it should select it explicitly. Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Acked-by: Don Zickus <dzickus@redhat.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Cc: David Howells <dhowells@redhat.com> Cc: David Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23locking/kconfig: Simplify INLINE_SPIN_UNLOCK usageRaghavendra K T
Get rid of INLINE_SPIN_UNLOCK entirely replacing it with UNINLINE_SPIN_UNLOCK instead of the reverse meaning. Whoever wants to change the default spinlock inlining behavior and uninline the spinlocks for some weird reason, such as spinlock debugging, paravirt etc. can now all just select UNINLINE_SPIN_UNLOCK Original discussion at: https://lkml.org/lkml/2012/3/21/357 Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Chris Zankel <chris@zankel.net> Cc: linux-mips@linux-mips.org Link: http://lkml.kernel.org/r/20120322095502.30866.75756.sendpatchset@codeblue [ tidied up the changelog a bit ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-03-21idr: make idr_get_next() good for rcu_read_lock()Hugh Dickins
Make one small adjustment to idr_get_next(): take the height from the top layer (stable under RCU) instead of from the root (unprotected by RCU), as idr_find() does: so that it can be used with RCU locking. Copied comment on RCU locking from idr_find(). Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-21Merge branch 'kmap_atomic' of git://github.com/congwang/linuxLinus Torvalds
Pull kmap_atomic cleanup from Cong Wang. It's been in -next for a long time, and it gets rid of the (no longer used) second argument to k[un]map_atomic(). Fix up a few trivial conflicts in various drivers, and do an "evil merge" to catch some new uses that have come in since Cong's tree. * 'kmap_atomic' of git://github.com/congwang/linux: (59 commits) feature-removal-schedule.txt: schedule the deprecated form of kmap_atomic() for removal highmem: kill all __kmap_atomic() [swarren@nvidia.com: highmem: Fix ARM build break due to __kmap_atomic rename] drbd: remove the second argument of k[un]map_atomic() zcache: remove the second argument of k[un]map_atomic() gma500: remove the second argument of k[un]map_atomic() dm: remove the second argument of k[un]map_atomic() tomoyo: remove the second argument of k[un]map_atomic() sunrpc: remove the second argument of k[un]map_atomic() rds: remove the second argument of k[un]map_atomic() net: remove the second argument of k[un]map_atomic() mm: remove the second argument of k[un]map_atomic() lib: remove the second argument of k[un]map_atomic() power: remove the second argument of k[un]map_atomic() kdb: remove the second argument of k[un]map_atomic() udf: remove the second argument of k[un]map_atomic() ubifs: remove the second argument of k[un]map_atomic() squashfs: remove the second argument of k[un]map_atomic() reiserfs: remove the second argument of k[un]map_atomic() ocfs2: remove the second argument of k[un]map_atomic() ntfs: remove the second argument of k[un]map_atomic() ...
2012-03-20Merge tag 'driver-core-3.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core patches for 3.4-rc1 from Greg KH: "Here's the big driver core merge for 3.4-rc1. Lots of various things here, sysfs fixes/tweaks (with the nlink breakage reverted), dynamic debugging updates, w1 drivers, hyperv driver updates, and a variety of other bits and pieces, full information in the shortlog." * tag 'driver-core-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (78 commits) Tools: hv: Support enumeration from all the pools Tools: hv: Fully support the new KVP verbs in the user level daemon Drivers: hv: Support the newly introduced KVP messages in the driver Drivers: hv: Add new message types to enhance KVP regulator: Support driver probe deferral Revert "sysfs: Kill nlink counting." uevent: send events in correct order according to seqnum (v3) driver core: minor comment formatting cleanups driver core: move the deferred probe pointer into the private area drivercore: Add driver probe deferral mechanism DS2781 Maxim Stand-Alone Fuel Gauge battery and w1 slave drivers w1_bq27000: Only one thread can access the bq27000 at a time. w1_bq27000 - remove w1_bq27000_write w1_bq27000: remove unnecessary NULL test. sysfs: Fix memory leak in sysfs_sd_setsecdata(). intel_idle: Revert change of auto_demotion_disable_flags for Nehalem w1: Fix w1_bq27000 driver-core: documentation: fix up Greg's email address powernow-k6: Really enable auto-loading powernow-k7: Fix CPU family number ...
2012-03-20Merge branch 'perf-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf events changes for v3.4 from Ingo Molnar: - New "hardware based branch profiling" feature both on the kernel and the tooling side, on CPUs that support it. (modern x86 Intel CPUs with the 'LBR' hardware feature currently.) This new feature is basically a sophisticated 'magnifying glass' for branch execution - something that is pretty difficult to extract from regular, function histogram centric profiles. The simplest mode is activated via 'perf record -b', and the result looks like this in perf report: $ perf record -b any_call,u -e cycles:u branchy $ perf report -b --sort=symbol 52.34% [.] main [.] f1 24.04% [.] f1 [.] f3 23.60% [.] f1 [.] f2 0.01% [k] _IO_new_file_xsputn [k] _IO_file_overflow 0.01% [k] _IO_vfprintf_internal [k] _IO_new_file_xsputn 0.01% [k] _IO_vfprintf_internal [k] strchrnul 0.01% [k] __printf [k] _IO_vfprintf_internal 0.01% [k] main [k] __printf This output shows from/to branch columns and shows the highest percentage (from,to) jump combinations - i.e. the most likely taken branches in the system. "branches" can also include function calls and any other synchronous and asynchronous transitions of the instruction pointer that are not 'next instruction' - such as system calls, traps, interrupts, etc. This feature comes with (hopefully intuitive) flat ascii and TUI support in perf report. - Various 'perf annotate' visual improvements for us assembly junkies. It will now recognize function calls in the TUI and by hitting enter you can follow the call (recursively) and back, amongst other improvements. - Multiple threads/processes recording support in perf record, perf stat, perf top - which is activated via a comma-list of PIDs: perf top -p 21483,21485 perf stat -p 21483,21485 -ddd perf record -p 21483,21485 - Support for per UID views, via the --uid paramter to perf top, perf report, etc. For example 'perf top --uid mingo' will only show the tasks that I am running, excluding other users, root, etc. - Jump label restructurings and improvements - this includes the factoring out of the (hopefully much clearer) include/linux/static_key.h generic facility: struct static_key key = STATIC_KEY_INIT_FALSE; ... if (static_key_false(&key)) do unlikely code else do likely code ... static_key_slow_inc(); ... static_key_slow_inc(); ... The static_key_false() branch will be generated into the code with as little impact to the likely code path as possible. the static_key_slow_*() APIs flip the branch via live kernel code patching. This facility can now be used more widely within the kernel to micro-optimize hot branches whose likelihood matches the static-key usage and fast/slow cost patterns. - SW function tracer improvements: perf support and filtering support. - Various hardenings of the perf.data ABI, to make older perf.data's smoother on newer tool versions, to make new features integrate more smoothly, to support cross-endian recording/analyzing workflows better, etc. - Restructuring of the kprobes code, the splitting out of 'optprobes', and a corner case bugfix. - Allow the tracing of kernel console output (printk). - Improvements/fixes to user-space RDPMC support, allowing user-space self-profiling code to extract PMU counts without performing any system calls, while playing nice with the kernel side. - 'perf bench' improvements - ... and lots of internal restructurings, cleanups and fixes that made these features possible. And, as usual this list is incomplete as there were also lots of other improvements * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (120 commits) perf report: Fix annotate double quit issue in branch view mode perf report: Remove duplicate annotate choice in branch view mode perf/x86: Prettify pmu config literals perf report: Enable TUI in branch view mode perf report: Auto-detect branch stack sampling mode perf record: Add HEADER_BRANCH_STACK tag perf record: Provide default branch stack sampling mode option perf tools: Make perf able to read files from older ABIs perf tools: Fix ABI compatibility bug in print_event_desc() perf tools: Enable reading of perf.data files from different ABI rev perf: Add ABI reference sizes perf report: Add support for taken branch sampling perf record: Add support for sampling taken branch perf tools: Add code to support PERF_SAMPLE_BRANCH_STACK x86/kprobes: Split out optprobe related code to kprobes-opt.c x86/kprobes: Fix a bug which can modify kernel code permanently x86/kprobes: Fix instruction recovery on optimized path perf: Add callback to flush branch_stack on context switch perf: Disable PERF_SAMPLE_BRANCH_* when not supported perf/x86: Add LBR software filter support for Intel CPUs ...
2012-03-20Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU changes for v3.4 from Ingo Molnar. The major features of this series are: - making RCU more aggressive about entering dyntick-idle mode in order to improve energy efficiency - converting a few more call_rcu()s to kfree_rcu()s - applying a number of rcutree fixes and cleanups to rcutiny - removing CONFIG_SMP #ifdefs from treercu - allowing RCU CPU stall times to be set via sysfs - adding CPU-stall capability to rcutorture - adding more RCU-abuse diagnostics - updating documentation - fixing yet more issues located by the still-ongoing top-to-bottom inspection of RCU, this time with a special focus on the CPU-hotplug code path. * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (48 commits) rcu: Stop spurious warnings from synchronize_sched_expedited rcu: Hold off RCU_FAST_NO_HZ after timer posted rcu: Eliminate softirq-mediated RCU_FAST_NO_HZ idle-entry loop rcu: Add RCU_NONIDLE() for idle-loop RCU read-side critical sections rcu: Allow nesting of rcu_idle_enter() and rcu_idle_exit() rcu: Remove redundant check for rcu_head misalignment PTR_ERR should be called before its argument is cleared. rcu: Convert WARN_ON_ONCE() in rcu_lock_acquire() to lockdep rcu: Trace only after NULL-pointer check rcu: Call out dangers of expedited RCU primitives rcu: Rework detection of use of RCU by offline CPUs lockdep: Add CPU-idle/offline warning to lockdep-RCU splat rcu: No interrupt disabling for rcu_prepare_for_idle() rcu: Move synchronize_sched_expedited() to rcutree.c rcu: Check for illegal use of RCU from offlined CPUs rcu: Update stall-warning documentation rcu: Add CPU-stall capability to rcutorture rcu: Make documentation give more realistic rcutorture duration rcutorture: Permit holding off CPU-hotplug operations during boot rcu: Print scheduling-clock information on RCU CPU stall-warning messages ...
2012-03-20lib: remove the second argument of k[un]map_atomic()Cong Wang
Signed-off-by: Cong Wang <amwang@redhat.com>