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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
..
lzo lzo: fix typo in decompressor 2008-04-10 15:34:05 -07:00
reed_solomon lib: Remove unnecessary inclusions of asm/semaphore.h 2008-04-18 22:17:17 -04:00
zlib_deflate lib/: Spelling fixes 2008-02-03 17:48:52 +02:00
zlib_inflate [ZLIB]: Fix external builds of zlib_inflate code. 2007-10-11 22:17:20 -07:00
.gitignore
argv_split.c LIB: Replace inappropriate include of <linux/bug.h> 2007-10-20 00:26:10 +02:00
audit.c
bitmap.c cpumask: add cpumask_scnprintf_len function 2008-04-19 19:44:58 +02:00
bitrev.c
bug.c
bust_spinlocks.c handle recursive calls to bust_spinlocks() 2007-10-17 08:42:56 -07:00
check_signature.c
cmdline.c
cpumask.c
crc7.c CRC7 support 2007-07-17 10:23:04 -07:00
crc16.c
crc32.c lib/: Spelling fixes 2008-02-03 17:48:52 +02:00
crc32defs.h
crc-ccitt.c
crc-itu-t.c
ctype.c
debug_locks.c
dec_and_lock.c
devres.c devres: implement pcim_iomap_regions_request_all() 2008-03-17 08:26:44 -04:00
div64.c
dump_stack.c
extable.c lib/extable.c: remove an expensive integer divide in search_extable() 2008-02-06 10:41:08 -08:00
fault-inject.c libfs: allow error return from simple attributes 2008-02-08 09:22:34 -08:00
find_next_bit.c x86, generic: optimize find_next_(zero_)bit for small constant-size bitmaps 2008-04-26 19:21:16 +02:00
gen_crc32table.c
genalloc.c Slab allocators: Replace explicit zeroing with __GFP_ZERO 2007-07-17 10:23:02 -07:00
halfmd4.c
hexdump.c hexdump: don't print bytes with bit 7 set 2007-11-29 09:24:53 -08:00
hweight.c remove asm/bitops.h includes 2007-10-19 11:53:41 -07:00
idr.c Slab API: remove useless ctor parameter and reorder parameters 2007-10-17 08:42:45 -07:00
inflate.c
int_sqrt.c
iomap_copy.c
iomap.c x86-32: Pass the full resource data to ioremap() 2008-03-24 11:22:39 -07:00
iommu-helper.c iommu: export iommu_is_span_boundary helper function 2008-03-04 16:35:17 -08:00
ioremap.c lib/ioremap.c should #include <linux/io.h> 2007-10-17 08:42:50 -07:00
irq_regs.c
kasprintf.c lib: move kasprintf to a separate file 2007-07-31 15:39:39 -07:00
Kconfig [LIB]: Make PowerPC LMB code generic so sparc64 can use it too. 2008-02-13 16:56:49 -08:00
Kconfig.debug Add option to enable -Wframe-larger-than= on gcc 4.4 2008-04-25 20:23:47 +02:00
Kconfig.kgdb kgdb: allow static kgdbts boot configuration 2008-04-17 20:05:43 +02:00
kernel_lock.c Convert asm/semaphore.h users to linux/semaphore.h 2008-04-18 22:22:54 -04:00
klist.c
kobject_uevent.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2008-04-03 14:33:42 -07:00
kobject.c Kobject: Replace list_for_each() with list_for_each_entry(). 2008-04-19 19:10:27 -07:00
kref.c kref: add kref_set() 2008-01-24 20:40:05 -08:00
libcrc32c.c [LIB] crc32c: Keep intermediate crc state in cpu order 2007-11-08 21:34:09 +08:00
list_debug.c
lmb.c [LMB]: Fix lmb allocation regression. 2008-04-23 23:30:59 -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
Makefile Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc 2008-04-21 15:50:49 -07:00
parser.c
percpu_counter.c Add irq protection in the percpu-counters cpu-hotplug-callback path 2007-10-19 11:53:44 -07:00
plist.c
prio_heap.c Fix cpusets update_cpumask 2007-10-19 11:53:41 -07:00
prio_tree.c
proportions.c lib: proportion: fix underflow in prop_norm_percpu() 2007-12-23 12:54:37 -08:00
radix-tree.c radix-tree: avoid atomic allocations for preloaded insertions 2008-02-05 09:44:17 -08:00
random32.c [NET]: srandom32 fixes for networking v2 2008-04-03 14:07:02 -07:00
rbtree.c
reciprocal_div.c
rwsem-spinlock.c lib: remove fastcall from lib/* 2008-02-08 09:22:31 -08:00
rwsem.c x86: fix UML and -regparm=3 2008-01-30 13:33:00 +01:00
scatterlist.c [SCSI] block: add sg buffer copy helper functions 2008-04-07 12:15:45 -05:00
sha1.c
smp_processor_id.c debug_smp_processor_id() fixlets 2008-02-06 10:41:09 -08:00
sort.c lib/sort.c optimization 2007-10-17 08:42:52 -07:00
spinlock_debug.c Use helpers to obtain task pid in printks 2007-10-19 11:53:43 -07:00
string.c
swiotlb.c avoid endless loops in lib/swiotlb.c 2008-03-13 13:15:52 -07:00
textsearch.c [TEXTSEARCH]: Do not allow zero length patterns in the textsearch infrastructure 2007-12-01 00:03:52 +11:00
ts_bm.c
ts_fsm.c
ts_kmp.c
vsprintf.c lib/vsprintf.c: fix bug omitting minus sign of numbers (module_param) 2008-02-23 17:12:14 -08:00