linux/include/asm-generic/bitops, branch v2.6.27.7

bitops: use __fls for fls64 on 64-bit archs

2008-04-26T17:21:16Z

Use __fls for fls64 on 64-bit archs. The implementation for 64-bit archs is moved from x86_64 to asm-generic. Signed-off-by: Alexander van Heukelum Signed-off-by: Ingo Molnar

generic: introduce a generic __fls implementation

2008-04-26T17:21:16Z

Add a generic __fls implementation in the same spirit as the generic __ffs one. It finds the last (most significant) set bit in the given long value. Signed-off-by: Alexander van Heukelum Signed-off-by: Ingo Molnar

x86, generic: optimize find_next_(zero_)bit for small constant-size bitmaps

2008-04-26T17:21:16Z

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

ext4: Add ext4_find_next_bit()

2008-01-29T04:58:27Z

This function is used by the ext4 multi block allocator patches. Also add generic_find_next_le_bit Signed-off-by: Aneesh Kumar K.V Cc: Signed-off-by: Andrew Morton

define first set of BIT* macros

2007-10-19T18:53:42Z

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 Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

bitops: introduce lock ops

2007-10-18T21:37:29Z

Introduce test_and_set_bit_lock / clear_bit_unlock bitops with lock semantics. Convert all architectures to use the generic implementation. Signed-off-by: Nick Piggin Acked-By: David Howells Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: Russell King Cc: Haavard Skinnemoen Cc: Bryan Wu Cc: Mikael Starvik Cc: David Howells Cc: Yoshinori Sato Cc: "Luck, Tony" Cc: Hirokazu Takata Cc: Geert Uytterhoeven Cc: Roman Zippel Cc: Greg Ungerer Cc: Ralf Baechle Cc: Kyle McMartin Cc: Matthew Wilcox Cc: Paul Mackerras Cc: Benjamin Herrenschmidt Cc: Heiko Carstens Cc: Martin Schwidefsky Cc: Paul Mundt Cc: Kazumoto Kojima Cc: Richard Curnow Cc: William Lee Irwin III Cc: "David S. Miller" Cc: Jeff Dike Cc: Paolo 'Blaisorblade' Giarrusso Cc: Miles Bader Cc: Andi Kleen Cc: Chris Zankel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

sched: simplify sched_find_first_bit()

2007-07-09T16:52:00Z

simplify sched_rt.c's sched_find_first_bit() function: there are only 100 RT priority levels left. Signed-off-by: Ingo Molnar

Fix misspellings collected by members of KJ list.

2007-05-09T05:14:03Z

Fix the misspellings of "propogate", "writting" and (oh, the shame :-) "kenrel" in the source tree. Signed-off-by: Robert P. J. Day Signed-off-by: Adrian Bunk

[PATCH] sched: likely profiling

2006-10-11T18:14:22Z

This likely profiling is pretty fun. I found a few possible problems in sched.c. This patch may be not measurable, but when I did measure long ago, nooping (un)likely cost a couple of % on scheduler heavy benchmarks, so it all adds up. Tweak some branch hints: - the 2nd 64 bits in the bitmask is likely to be populated, because it contains the first 28 bits (nearly 3/4) of the normal priorities. (ratio of 669669:691 ~= 1000:1). - it isn't unlikely that context switching switches to another process. it might be very rapidly switching to and from the idle process (ratio of 475815:419004 and 471330:423544). Let the branch predictor decide. - preempt_enable seems to be very often called in a nested preempt_disable or with interrupts disabled (ratio of 3567760:87965 ~= 40:1) Signed-off-by: Nick Piggin Acked-by: Ingo Molnar Cc: Daniel Walker Cc: Hua Zhong Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] bitops: generic minix_{test,set,test_and_clear,test,find_first_zero}_bit()

2006-03-26T16:57:11Z

This patch introduces the C-language equivalents of the functions below: int minix_test_and_set_bit(int nr, volatile unsigned long *addr); int minix_set_bit(int nr, volatile unsigned long *addr); int minix_test_and_clear_bit(int nr, volatile unsigned long *addr); int minix_test_bit(int nr, const volatile unsigned long *addr); unsigned long minix_find_first_zero_bit(const unsigned long *addr, unsigned long size); In include/asm-generic/bitops/minix.h and include/asm-generic/bitops/minix-le.h This code largely copied from: include/asm-sparc/bitops.h Signed-off-by: Akinobu Mita Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds