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* asm-generic: add another generic ext2 atomic bitopsAkinobu Mita2011-07-261-4/+1
| | | | | | | | | | | | | | | The majority of architectures implement ext2 atomic bitops as test_and_{set,clear}_bit() without spinlock. This adds this type of generic implementation in ext2-atomic-setbit.h and use it wherever possible. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Suggested-by: Andreas Dilger <adilger@dilger.ca> Suggested-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* bitops: remove minix bitops from asm/bitops.hAkinobu Mita2011-03-231-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | minix bit operations are only used by minix filesystem and useless by other modules. Because byte order of inode and block bitmaps is different on each architecture like below: m68k: big-endian 16bit indexed bitmaps h8300, microblaze, s390, sparc, m68knommu: big-endian 32 or 64bit indexed bitmaps m32r, mips, sh, xtensa: big-endian 32 or 64bit indexed bitmaps for big-endian mode little-endian bitmaps for little-endian mode Others: little-endian bitmaps In order to move minix bit operations from asm/bitops.h to architecture independent code in minix filesystem, this provides two config options. CONFIG_MINIX_FS_BIG_ENDIAN_16BIT_INDEXED is only selected by m68k. CONFIG_MINIX_FS_NATIVE_ENDIAN is selected by the architectures which use native byte order bitmaps (h8300, microblaze, s390, sparc, m68knommu, m32r, mips, sh, xtensa). The architectures which always use little-endian bitmaps do not select these options. Finally, we can remove minix bit operations from asm/bitops.h for all architectures. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Greg Ungerer <gerg@uclinux.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Andreas Schwab <schwab@linux-m68k.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Michal Simek <monstr@monstr.eu> Cc: "David S. Miller" <davem@davemloft.net> Cc: Hirokazu Takata <takata@linux-m32r.org> Acked-by: Ralf Baechle <ralf@linux-mips.org> Acked-by: Paul Mundt <lethal@linux-sh.org> Cc: Chris Zankel <chris@zankel.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* bitops: remove ext2 non-atomic bitops from asm/bitops.hAkinobu Mita2011-03-231-1/+0
| | | | | | | | | | | | As the result of conversions, there are no users of ext2 non-atomic bit operations except for ext2 filesystem itself. Now we can put them into architecture independent code in ext2 filesystem, and remove from asm/bitops.h for all architectures. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* bitops: introduce little-endian bitops for most architecturesAkinobu Mita2011-03-231-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce little-endian bit operations to the big-endian architectures which do not have native little-endian bit operations and the little-endian architectures. (alpha, avr32, blackfin, cris, frv, h8300, ia64, m32r, mips, mn10300, parisc, sh, sparc, tile, x86, xtensa) These architectures can just include generic implementation (asm-generic/bitops/le.h). Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Mikael Starvik <starvik@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Matthew Wilcox <willy@debian.org> Cc: Grant Grundler <grundler@parisc-linux.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Chris Zankel <chris@zankel.net> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com> Acked-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* bitops: make asm-generic/bitops/find.h more genericAkinobu Mita2010-10-091-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | asm-generic/bitops/find.h has the extern declarations of find_next_bit() and find_next_zero_bit() and the macro definitions of find_first_bit() and find_first_zero_bit(). It is only usable by the architectures which enables CONFIG_GENERIC_FIND_NEXT_BIT and disables CONFIG_GENERIC_FIND_FIRST_BIT. x86 and tile enable both CONFIG_GENERIC_FIND_NEXT_BIT and CONFIG_GENERIC_FIND_FIRST_BIT. These architectures cannot include asm-generic/bitops/find.h in their asm/bitops.h. So ifdefed extern declarations of find_first_bit and find_first_zero_bit() are put in linux/bitops.h. This makes asm-generic/bitops/find.h usable by these architectures and use it. Also this change is needed for the forthcoming duplicated extern declarations cleanup. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Cc: Chris Metcalf <cmetcalf@tilera.com>
* x86: Avoid 'constant_test_bit()' misoptimization due to cast to non-volatileAlexander Chumachenko2010-09-261-1/+1
| | | | | | | | | | | | | | | | | | | | | While debugging bit_spin_lock() hang, it was tracked down to gcc-4.4 misoptimization of non-inlined constant_test_bit() due to non-volatile addr when 'const volatile unsigned long *addr' cast to 'unsigned long *' with subsequent unconditional jump to pause (and not to the test) leading to hang. Compiling with gcc-4.3 or disabling CONFIG_OPTIMIZE_INLINING yields inlined constant_test_bit() and correct jump, thus working around the kernel bug. Other arches than asm-x86 may implement this slightly differently; 2.6.29 mitigates the misoptimization by changing the function prototype (commit c4295fbb6048d85f0b41c5ced5cbf63f6811c46c) but probably fixing the issue itself is better. Signed-off-by: Alexander Chumachenko <ledest@gmail.com> Signed-off-by: Michael Shigorin <mike@osdn.org.ua> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86: Add optimized popcnt variantsBorislav Petkov2010-04-061-1/+3
| | | | | | | | | | | | | | Add support for the hardware version of the Hamming weight function, popcnt, present in CPUs which advertize it under CPUID, Function 0x0000_0001_ECX[23]. On CPUs which don't support it, we fallback to the default lib/hweight.c sw versions. A synthetic benchmark comparing popcnt with __sw_hweight64 showed almost a 3x speedup on a F10h machine. Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> LKML-Reference: <20100318112015.GC11152@aftab> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, generic: mark complex bitops.h inlines as __always_inlineAndi Kleen2009-01-131-4/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: reduce kernel image size Hugh Dickins noticed that older gcc versions when the kernel is built for code size didn't inline some of the bitops. Mark all complex x86 bitops that have more than a single asm statement or two as always inline to avoid this problem. Probably should be done for other architectures too. Ingo then found a better fix that only requires a single line change, but it unfortunately only works on gcc 4.3. On older gccs the original patch still makes a ~0.3% defconfig difference with CONFIG_OPTIMIZE_INLINING=y. With gcc 4.1 and a defconfig like build: 6116998 1138540 883788 8139326 7c323e vmlinux-oi-with-patch 6137043 1138540 883788 8159371 7c808b vmlinux-optimize-inlining ~20k / 0.3% difference. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: make 'constant_test_bit()' take an unsigned bit numberLinus Torvalds2009-01-091-1/+1
| | | | | | | | | | Ingo noticed that using signed arithmetic seems to confuse the gcc inliner, and make it potentially decide that it's all too complicated. (Yeah, yeah, it's a constant. It's always positive. Still..) Based-on: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86: Implement change_bit with immediate operand as "lock xorb"Uros Bizjak2008-11-051-1/+9
| | | | | | | | | | | Impact: Minor optimization. Implement change_bit with immediate bit count as "lock xorb". This is similar to "lock orb" and "lock andb" for set_bit and clear_bit functions. Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86: Fix ASM_X86__ header guardsH. Peter Anvin2008-10-221-3/+3
| | | | | | | | | Change header guards named "ASM_X86__*" to "_ASM_X86_*" since: a. the double underscore is ugly and pointless. b. no leading underscore violates namespace constraints. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: ... and asm-x86 moveAl Viro2008-10-221-0/+451
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
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