26 Jun, 2006
8 commits
-
I ran into a bug where the kernel died in the idr code:
cpu 0x1d: Vector: 300 (Data Access) at [c000000b7096f710]
pc: c0000000001f8984: .idr_get_new_above_int+0x140/0x330
lr: c0000000001f89b4: .idr_get_new_above_int+0x170/0x330
sp: c000000b7096f990
msr: 800000000000b032
dar: 0
dsisr: 40010000
current = 0xc000000b70d43830
paca = 0xc000000000556900
pid = 2022, comm = hwup
1d:mon> t
[c000000b7096f990] c0000000000d2ad8 .expand_files+0x2e8/0x364 (unreliable)
[c000000b7096faa0] c0000000001f8bf8 .idr_get_new_above+0x18/0x68
[c000000b7096fb20] c00000000002a054 .init_new_context+0x5c/0xf0
[c000000b7096fbc0] c000000000049dc8 .copy_process+0x91c/0x1404
[c000000b7096fcd0] c00000000004a988 .do_fork+0xd8/0x224
[c000000b7096fdc0] c00000000000ebdc .sys_clone+0x5c/0x74
[c000000b7096fe30] c000000000008950 .ppc_clone+0x8/0xc -
Implement kasprintf, a kernel version of asprintf. This allocates the
memory required for the formatted string, including the trailing '\0'.
Returns NULL on allocation failure.Signed-off-by: Jeremy Fitzhardinge
Signed-off-by: Chris Wright
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This change allows callers to use a 0-byte buffer and a NULL buffer pointer
with vsnprintf, so it can be used to determine how large the resulting
formatted string will be.Previously the code effectively treated a size of 0 as a size of 4G (on
32-bit systems), with other checks preventing it from actually trying to
emit the string - but the terminal \0 would still be written, which would
crash if the buffer is NULL.This change changes the boundary check so that 'end' points to the putative
location of the terminal '\0', which is only written if size > 0.vsnprintf still allows the buffer size to be set very large, to allow
unbounded buffer sizes (to implement sprintf, etc).[akpm@osdl.org: fix long-vs-longlong confusion]
Signed-off-by: Jeremy Fitzhardinge
Signed-off-by: Chris Wright
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Fix kernel-doc formatting in Reed-Solomon code.
Signed-off-by: Randy Dunlap
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Make kernel-doc corrections & additions to lib/crc*.c. Add crc functions to
kernel-api.tmpl in DocBook.Signed-off-by: Randy Dunlap
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Make corrections/fixes to kernel-doc in lib/bitmap.c and include it in DocBook
template.Signed-off-by: Randy Dunlap
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
In radix_tree_tag_get(), return normalized value of 0/1, as indicated
by its comment.Signed-off-by: Wu Fengguang
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
constify a medium-large CRC code table.
Signed-off-by: Andreas Mohr
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
23 Jun, 2006
8 commits
-
Add a new strstrip() function to lib/string.c for removing leading and
trailing whitespace from a string.Cc: Michael Holzheu
Acked-by: Ingo Oeser
Acked-by: Joern Engel
Cc: Corey Minyard
Signed-off-by: Pekka Enberg
Acked-by: Michael Holzheu
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The percpu counter data type are changed in this set of patches to support
more users like ext3 who need more than 32 bit to store the free blocks
total in the filesystem.- Generic perpcu counters data type changes. The size of the global counter
and local counter were explictly specified using s64 and s32. The global
counter is changed from long to s64, while the local counter is changed from
long to s32, so we could avoid doing 64 bit update in most cases.- Users of the percpu counters are updated to make use of the new
percpu_counter_init() routine now taking an additional parameter to allow
users to pass the initial value of the global counter.Signed-off-by: Mingming Cao
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
- Move percpu_counter routines from mm/swap.c to lib/percpu_counter.c
Signed-off-by: Ravikiran Thirumalai
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The comment states: 'Setting a tag on a not-present item is a BUG.' Hence
if 'index' is larger than the maxindex; the item _cannot_ be presen; it
should also be a BUG.Also, this allows the following statement (assume a fresh tree):
radix_tree_tag_set(root, 16, 1);
to fail silently, but when preceded by:
radix_tree_insert(root, 32, item);
it would BUG, because the height has been extended by the insert.
In neither case was 16 present.
Signed-off-by: Peter Zijlstra
Acked-by: Nick Piggin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Reduce radix tree node memory usage by about a factor of 4 for small files
(< 64K). There are pointer traversal and memory usage costs for large
files with dense pagecache.Signed-off-by: Nick Piggin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The ability to have height 0 radix trees (a direct pointer to the data item
rather than going through a full node->slot) quietly disappeared with
old-2.6-bkcvs commit ffee171812d51652f9ba284302d9e5c5cc14bdfd. On 64-bit
machines this causes nearly 600 bytes to be used for every gfp_mask bits.Simplify radix_tree_delete's complex tag clearing arrangement (which would
become even more complex) by just falling back to tag clearing functions
(the pagecache radix-tree never uses this path anyway, so the icache
savings will mean it's actually a speedup).On my 4GB G5, this saves 8MB RAM per kernel kernel source+object tree in
pagecache.Pagecache lookup, insertion, and removal speed for small files will also be
improved.This makes RCU radix tree harder, but it's worth it.
Signed-off-by: Nick Piggin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Modify the gen_pool allocator (lib/genalloc.c) to utilize a bitmap scheme
instead of the buddy scheme. The purpose of this change is to eliminate
the touching of the actual memory being allocated.Since the change modifies the interface, a change to the uncached allocator
(arch/ia64/kernel/uncached.c) is also required.Both Andrey Volkov and Jes Sorenson have expressed a desire that the
gen_pool allocator not write to the memory being managed. See the
following:http://marc.theaimsgroup.com/?l=linux-kernel&m=113518602713125&w=2
http://marc.theaimsgroup.com/?l=linux-kernel&m=113533568827916&w=2Signed-off-by: Dean Nelson
Cc: Andrey Volkov
Acked-by: Jes Sorensen
Cc: "Luck, Tony"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Upgrade the zlib_inflate implementation in the kernel from a patched
version 1.1.3/4 to a patched 1.2.3.The code in the kernel is about seven years old and I noticed that the
external zlib library's inflate performance was significantly faster (~50%)
than the code in the kernel on ARM (and faster again on x86_32).For comparison the newer deflate code is 20% slower on ARM and 50% slower
on x86_32 but gives an approx 1% compression ratio improvement. I don't
consider this to be an improvement for kernel use so have no plans to
change the zlib_deflate code.Various changes have been made to the zlib code in the kernel, the most
significant being the extra functions/flush option used by ppp_deflate.
This update reimplements the features PPP needs to ensure it continues to
work.This code has been tested on ARM under both JFFS2 (with zlib compression
enabled) and ppp_deflate and on x86_32. JFFS2 sees an approx. 10% real
world file read speed improvement.This patch also removes ZLIB_VERSION as it no longer has a correct value.
We don't need version checks anyway as the kernel's module handling will
take care of that for us. This removal is also more in keeping with the
zlib author's wishes (http://www.zlib.net/zlib_faq.html#faq24) and I've
added something to the zlib.h header to note its a modified version.Signed-off-by: Richard Purdie
Acked-by: Joern Engel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
22 Jun, 2006
1 commit
-
These really need to be fixed, shout it out to the world.
Signed-off-by: Greg Kroah-Hartman
21 Jun, 2006
2 commits
-
Introduce __iowrite64_copy. It will be used by the Myri-10G Ethernet
driver to post requests to the NIC. This driver will be submitted soon.__iowrite64_copy copies to I/O memory in units of 64 bits when possible (on
64 bit architectures). It reverts to __iowrite32_copy on 32 bit
architectures.Signed-off-by: Brice Goglin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
* git://git.infradead.org/~dwmw2/rbtree-2.6:
[RBTREE] Switch rb_colour() et al to en_US spelling of 'color' for consistency
Update UML kernel/physmem.c to use rb_parent() accessor macro
[RBTREE] Update hrtimers to use rb_parent() accessor macro.
[RBTREE] Add explicit alignment to sizeof(long) for struct rb_node.
[RBTREE] Merge colour and parent fields of struct rb_node.
[RBTREE] Remove dead code in rb_erase()
[RBTREE] Update JFFS2 to use rb_parent() accessor macro.
[RBTREE] Update eventpoll.c to use rb_parent() accessor macro.
[RBTREE] Update key.c to use rb_parent() accessor macro.
[RBTREE] Update ext3 to use rb_parent() accessor macro.
[RBTREE] Change rbtree off-tree marking in I/O schedulers.
[RBTREE] Add accessor macros for colour and parent fields of rb_node
06 Jun, 2006
1 commit
-
Since rb_insert_color() is part of the _public_ API, while the others are
purely internal, switch to be consistent with that.Signed-off-by: David Woodhouse
22 May, 2006
1 commit
-
People don't like released kernels yelling at them, no matter how real the
error might be. So only report it if CONFIG_KOBJECT_DEBUG is enabled.Sent on request of Andrew Morton.
(akpm: should bring this back post-2.6.17)
Signed-off-by: Greg Kroah-Hartman
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
13 May, 2006
1 commit
-
For sparc32 we need R_SPARC_UA32 relocation support, for
sparc64 we need the handle R_SPARC_DISP32 relocations.Based upon reports and initial patch by Martin Habets.
Signed-off-by: David S. Miller
28 Apr, 2006
2 commits
-
This patch contains the following possible cleanups:
- #if 0 the following unused global function:
- subsys_remove_file()
- remove the following unused EXPORT_SYMBOL's:
- kset_find_obj
- subsystem_init
- remove the following unused EXPORT_SYMBOL_GPL:
- kobject_add_dirSigned-off-by: Adrian Bunk
Signed-off-by: Greg Kroah-Hartman -
This fixes a build error for various odd combinations of CONFIG_HOTPLUG
and CONFIG_NET.Signed-off-by: Kay Sievers
Cc: Nigel Cunningham
Cc: Andrew Morton
Signed-off-by: Greg Kroah-Hartman
21 Apr, 2006
2 commits
-
We only used a single bit for colour information, so having a whole
machine word of space allocated for it was a bit wasteful. Instead,
store it in the lowest bit of the 'parent' pointer, since that was
always going to be aligned anyway.Signed-off-by: David Woodhouse
-
Observe rb_erase(), when the victim node 'old' has two children so
neither of the simple cases at the beginning are taken.Observe that it effectively does an 'rb_next()' operation to find the
next (by value) node in the tree. That is; we go to the victim's
right-hand child and then follow left-hand pointers all the way
down the tree as far as we can until we find the next node 'node'. We
end up with 'node' being either the same immediate right-hand child of
'old', or one of its descendants on the far left-hand side.For a start, we _know_ that 'node' has a parent. We can drop that check.
We also know that if 'node's parent is 'old', then 'node' is the
right-hand child of its parent. And that if 'node's parent is _not_
'old', then 'node' is the left-hand child of its parent.So instead of checking for 'node->rb_parent == old' in one place and
also checking 'node's heritage separately when we're trying to change
its link from its parent, we can shuffle things around a bit and do
it like this...Signed-off-by: David Woodhouse
20 Apr, 2006
1 commit
-
DEBUG_MUTEX flag is on by default in current kernel configuration.
During performance testing, we saw mutex debug functions like
mutex_debug_check_no_locks_freed (called by kfree()) is expensive as it
goes through a global list of memory areas with mutex lock and do the
checking. For benchmarks such as Volanomark and Hackbench, we have seen
more than 40% drop in performance on some platforms. We suggest to set
DEBUG_MUTEX off by default. Or at least do that later when we feel that
the mutex changes in the current code have stabilized.Signed-off-by: Tim Chen
Cc: Ingo Molnar
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
15 Apr, 2006
1 commit
-
It works like this:
Open the file
Read all the contents.
Call poll requesting POLLERR or POLLPRI (so select/exceptfds works)
When poll returns,
close the file and go to top of loop.
or lseek to start of file and go back to the 'read'.Events are signaled by an object manager calling
sysfs_notify(kobj, dir, attr);If the dir is non-NULL, it is used to find a subdirectory which
contains the attribute (presumably created by sysfs_create_group).This has a cost of one int per attribute, one wait_queuehead per kobject,
one int per open file.The name "sysfs_notify" may be confused with the inotify
functionality. Maybe it would be nice to support inotify for sysfs
attributes as well?This patch also uses sysfs_notify to allow /sys/block/md*/md/sync_action
to be pollableSigned-off-by: Neil Brown
Signed-off-by: Greg Kroah-Hartman
11 Apr, 2006
3 commits
-
lib/string.c: In function 'memcpy':
lib/string.c:470: warning: initialization discards qualifiers from pointer =
target typeSigned-off-by: Jan-Benedict Glaw
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Some string functions were safely overrideable in lib/string.c, but their
corresponding declarations in linux/string.h were not. Correct this, and
make strcspn overrideable.Odds of someone wanting to do optimized assembly of these are small, but
for the sake of cleanliness, might as well bring them into line with the
rest of the file.Signed-off-by: Kyle McMartin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
While cleaning up parisc_ksyms.c earlier, I noticed that strpbrk wasn't
being exported from lib/string.c. Investigating further, I noticed a
changeset that removed its export and added it to _ksyms.c on a few more
architectures. The justification was that "other arches do it."I think this is wrong, since no architecture currently defines
__HAVE_ARCH_STRPBRK, there's no reason for any of them to be exporting it
themselves. Therefore, consolidate the export to lib/string.c.Signed-off-by: Kyle McMartin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
31 Mar, 2006
1 commit
-
Remove CONFIG_DEBUG_IOREMAP, it's now obsolete and won't work anyway.
Remove it from lib/KConfig since it was only available on parisc.Signed-off-by: Helge Deller
Signed-off-by: Kyle McMartin
27 Mar, 2006
6 commits
-
We use it generally now, at least blktrace isn't a specific debug
kernel feature.Signed-off-by: Jens Axboe
-
wrote:
This is an extremely well-known technique. You can see a similar version that
uses a multiply for the last few steps at
http://graphics.stanford.edu/~seander/bithacks.html#CountBitsSetParallel whch
refers to "Software Optimization Guide for AMD Athlon 64 and Opteron
Processors"
http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/25112.PDFIt's section 8.6, "Efficient Implementation of Population-Count Function in
32-bit Mode", pages 179-180.It uses the name that I am more familiar with, "popcount" (population count),
although "Hamming weight" also makes sense.Anyway, the proof of correctness proceeds as follows:
b = a - ((a >> 1) & 0x55555555);
c = (b & 0x33333333) + ((b >> 2) & 0x33333333);
d = (c + (c >> 4)) & 0x0f0f0f0f;
#if SLOW_MULTIPLY
e = d + (d >> 8)
f = e + (e >> 16);
return f & 63;
#else
/* Useful if multiply takes at most 4 cycles */
return (d * 0x01010101) >> 24;
#endifThe input value a can be thought of as 32 1-bit fields each holding their own
hamming weight. Now look at it as 16 2-bit fields. Each 2-bit field a1..a0
has the value 2*a1 + a0. This can be converted into the hamming weight of the
2-bit field a1+a0 by subtracting a1.That's what the (a >> 1) & mask subtraction does. Since there can be no
borrows, you can just do it all at once.Enumerating the 4 possible cases:
0b00 = 0 -> 0 - 0 = 0
0b01 = 1 -> 1 - 0 = 1
0b10 = 2 -> 2 - 1 = 1
0b11 = 3 -> 3 - 1 = 2The next step consists of breaking up b (made of 16 2-bir fields) into
even and odd halves and adding them into 4-bit fields. Since the largest
possible sum is 2+2 = 4, which will not fit into a 4-bit field, the 2-bit
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
"which will not fit into a 2-bit field"fields have to be masked before they are added.
After this point, the masking can be delayed. Each 4-bit field holds a
population count from 0..4, taking at most 3 bits. These numbers can be added
without overflowing a 4-bit field, so we can compute c + (c >> 4), and only
then mask off the unwanted bits.This produces d, a number of 4 8-bit fields, each in the range 0..8. From
this point, we can shift and add d multiple times without overflowing an 8-bit
field, and only do a final mask at the end.The number to mask with has to be at least 63 (so that 32 on't be truncated),
but can also be 128 or 255. The x86 has a special encoding for signed
immediate byte values -128..127, so the value of 255 is slower. On other
processors, a special "sign extend byte" instruction might be faster.On a processor with fast integer multiplies (Athlon but not P4), you can
reduce the final few serially dependent instructions to a single integer
multiply. Consider d to be 3 8-bit values d3, d2, d1 and d0, each in the
range 0..8. The multiply forms the partial products:d3 d2 d1 d0
d3 d2 d1 d0
d3 d2 d1 d0
+ d3 d2 d1 d0
----------------------
e3 e2 e1 e0Where e3 = d3 + d2 + d1 + d0. e2, e1 and e0 obviously cannot generate
any carries.Signed-off-by: Akinobu Mita
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
By defining generic hweight*() routines
- hweight64() will be defined on all architectures
- hweight_long() will use architecture optimized hweight32() or hweight64()I found two possible cleanups by these reasons.
Signed-off-by: Akinobu Mita
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch introduces the C-language equivalents of the functions below:
int ext2_set_bit(int nr, volatile unsigned long *addr);
int ext2_clear_bit(int nr, volatile unsigned long *addr);
int ext2_test_bit(int nr, const volatile unsigned long *addr);
unsigned long ext2_find_first_zero_bit(const unsigned long *addr,
unsigned long size);
unsinged long ext2_find_next_zero_bit(const unsigned long *addr,
unsigned long size);In include/asm-generic/bitops/ext2-non-atomic.h
This code largely copied from:
include/asm-powerpc/bitops.h
include/asm-parisc/bitops.hSigned-off-by: Akinobu Mita
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch introduces the C-language equivalents of the functions below:
unsigned int hweight32(unsigned int w);
unsigned int hweight16(unsigned int w);
unsigned int hweight8(unsigned int w);
unsigned long hweight64(__u64 w);In include/asm-generic/bitops/hweight.h
This code largely copied from: include/linux/bitops.h
Signed-off-by: Akinobu Mita
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch introduces the C-language equivalents of the functions below:
unsigned logn find_next_bit(const unsigned long *addr, unsigned long size,
unsigned long offset);
unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size,
unsigned long offset);
unsigned long find_first_zero_bit(const unsigned long *addr,
unsigned long size);
unsigned long find_first_bit(const unsigned long *addr, unsigned long size);In include/asm-generic/bitops/find.h
This code largely copied from: arch/powerpc/lib/bitops.c
Signed-off-by: Akinobu Mita
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
26 Mar, 2006
2 commits
-
DEBUG_KERNEL is often enabled just for sysrq, but this doesn't
mean the user wants more heavyweight debugging information.Cc: jbeulich@novell.com
Signed-off-by: Andi Kleen
Signed-off-by: Linus Torvalds -
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: (21 commits)
BUG_ON() Conversion in drivers/video/
BUG_ON() Conversion in drivers/parisc/
BUG_ON() Conversion in drivers/block/
BUG_ON() Conversion in sound/sparc/cs4231.c
BUG_ON() Conversion in drivers/s390/block/dasd.c
BUG_ON() Conversion in lib/swiotlb.c
BUG_ON() Conversion in kernel/cpu.c
BUG_ON() Conversion in ipc/msg.c
BUG_ON() Conversion in block/elevator.c
BUG_ON() Conversion in fs/coda/
BUG_ON() Conversion in fs/binfmt_elf_fdpic.c
BUG_ON() Conversion in input/serio/hil_mlc.c
BUG_ON() Conversion in md/dm-hw-handler.c
BUG_ON() Conversion in md/bitmap.c
The comment describing how MS_ASYNC works in msync.c is confusing
rcu: undeclared variable used in documentation
fix typos "wich" -> "which"
typo patch for fs/ufs/super.c
Fix simple typos
tabify drivers/char/Makefile
...
