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15 commits

Author SHA1 Message Date
Alexander van Heukelum
3a48305028 x86: optimize find_first_bit for small bitmaps
Avoid a call to find_first_bit if the bitmap size is know at
compile time and small enough to fit in a single long integer.
Modeled after an optimization in the original x86_64-specific
code.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-26 19:21:17 +02:00
Alexander van Heukelum
77b9bd9c49 x86: generic versions of find_first_(zero_)bit, convert i386
Generic versions of __find_first_bit and __find_first_zero_bit
are introduced as simplified versions of __find_next_bit and
__find_next_zero_bit. Their compilation and use are guarded by
a new config variable GENERIC_FIND_FIRST_BIT.

The generic versions of find_first_bit and find_first_zero_bit
are implemented in terms of the newly introduced __find_first_bit
and __find_first_zero_bit.

This patch does not remove the i386-specific implementation,
but it does switch i386 to use the generic functions by setting
GENERIC_FIND_FIRST_BIT=y for X86_32.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-26 19:21:16 +02:00
Alexander van Heukelum
64970b68d2 x86, generic: optimize find_next_(zero_)bit for small constant-size bitmaps
This moves an optimization for searching constant-sized small
bitmaps form x86_64-specific to generic code.

On an i386 defconfig (the x86#testing one), the size of vmlinux hardly
changes with this applied. I have observed only four places where this
optimization avoids a call into find_next_bit:

In the functions return_unused_surplus_pages, alloc_fresh_huge_page,
and adjust_pool_surplus, this patch avoids a call for a 1-bit bitmap.
In __next_cpu a call is avoided for a 32-bit bitmap. That's it.

On x86_64, 52 locations are optimized with a minimal increase in
code size:

Current #testing defconfig:
	146 x bsf, 27 x find_next_*bit
   text    data     bss     dec     hex filename
   5392637  846592  724424 6963653  6a41c5 vmlinux

After removing the x86_64 specific optimization for find_next_*bit:
	94 x bsf, 79 x find_next_*bit
   text    data     bss     dec     hex filename
   5392358  846592  724424 6963374  6a40ae vmlinux

After this patch (making the optimization generic):
	146 x bsf, 27 x find_next_*bit
   text    data     bss     dec     hex filename
   5392396  846592  724424 6963412  6a40d4 vmlinux

[ tglx@linutronix.de: build fixes ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-26 19:21:16 +02:00
Harvey Harrison
3afe392598 kernel: add bit rotation helpers for 16 and 8 bit
Will replace open-coded variants elsewhere.  Done in the same
style as the 32-bit versions.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John W. Linville <linville@tuxdriver.com>
Cc: Joe Perches <joe@perches.com>
Cc: Jiri Benc <jbenc@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-28 14:45:22 -07:00
Jiri Slaby
14ed9d23aa remove BITS_TO_TYPE macro
remove BITS_TO_TYPE macro

I realized, that it is actually the same as DIV_ROUND_UP, use it instead.

[akpm@linux-foundation.org: build fix]
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:42 -07:00
Jiri Slaby
93043ece03 define global BIT macro
define global BIT macro

move all local BIT defines to the new globally define macro.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Kumar Gala <galak@gate.crashing.org>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: "John W. Linville" <linville@tuxdriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:42 -07:00
Jiri Slaby
d05be13bcc define first set of BIT* macros
define first set of BIT* macros

- move BITOP_MASK and BITOP_WORD from asm-generic/bitops/atomic.h to
  include/linux/bitops.h and rename it to BIT_MASK and BIT_WORD
- move BITS_TO_LONGS and BITS_PER_BYTE to bitops.h too and allow easily
  define another BITS_TO_something (e.g. in event.c) by BITS_TO_TYPE macro
Remaining (and common) BIT macro will be defined after all occurences and
conflicts will be sorted out in the patches.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:42 -07:00
Shannon Nelson
3e037454bc I/OAT: Add support for MSI and MSI-X
Add support for MSI and MSI-X interrupt handling, including the ability
to choose the desired interrupt method.

Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Acked-by: David S. Miller <davem@davemloft.net>
[bunk@kernel.org: drivers/dma/ioat_dma.c: make 3 functions static]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:43:09 -07:00
Robert P. J. Day
45f8bde0d0 [PATCH] fix various kernel-doc in header files
Fix a number of kernel-doc entries for header files in include/linux by
making sure they begin with the appropriate '/**' notation and use @var
notation.

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-01-26 13:51:00 -08:00
Akinobu Mita
e9bebd6f3a [PATCH] bitops: remove unused generic bitops in include/linux/bitops.h
generic_{ffs,fls,fls64,hweight{64,32,16,8}}() were moved into
include/asm-generic/bitops.h.  So all architectures don't use them.

Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:57:15 -08:00
Andrew Morton
962749af67 [PATCH] roundup_pow_of_two() 64-bit fix
fls() takes an integer, so roundup_pow_of_two() is busted for ulongs larger
than 2^32-1.

Fix this by implementing and using fls_long().

(Why does roundup_pow_of_two() return a long?)

(Why is roundup_pow_of_two() __attribute_const__ whereas long_log2() is
__attribute_pure__?)

(Why does long_log2() suck so much?  Because we were missing fls_long()?)

Cc: Roland Dreier <rdreier@cisco.com>
Cc: "Chen, Kenneth W" <kenneth.w.chen@intel.com>
Cc: John Hawkes <hawkes@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:22:58 -08:00
Akinobu Mita
f434baf4c6 [PATCH] fix generic_fls64()
Noticed by Rune Torgersen.

Fix generic_fls64().  tcp_cubic is using fls64().

Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-03 08:32:00 -08:00
Stephen Hemminger
3821af2fe1 [FLS64]: generic version
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03 13:11:06 -08:00
Siddha, Suresh B
94605eff57 [PATCH] x86-64/i386: Intel HT, Multi core detection fixes
Fields obtained through cpuid vector 0x1(ebx[16:23]) and
vector 0x4(eax[14:25], eax[26:31]) indicate the maximum values and might not
always be the same as what is available and what OS sees.  So make sure
"siblings" and "cpu cores" values in /proc/cpuinfo reflect the values as seen
by OS instead of what cpuid instruction says. This will also fix the buggy BIOS
cases (for example where cpuid on a single core cpu says there are "2" siblings,
even when HT is disabled in the BIOS.
http://bugzilla.kernel.org/show_bug.cgi?id=4359)

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-14 19:55:16 -08:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00