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2015-12-09bitops.h: correctly handle rol32 with 0 byte shiftSasha Levin1-1/+1
ROL on a 32 bit integer with a shift of 32 or more is undefined and the result is arch-dependent. Avoid this by handling the trivial case of roling by 0 correctly. The trivial solution of checking if shift is 0 breaks gcc's detection of this code as a ROL instruction, which is unacceptable. This bug was reported and fixed in GCC (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=57157): The standard rotate idiom, (x << n) | (x >> (32 - n)) is recognized by gcc (for concreteness, I discuss only the case that x is an uint32_t here). However, this is portable C only for n in the range 0 < n < 32. For n == 0, we get x >> 32 which gives undefined behaviour according to the C standard (6.5.7, Bitwise shift operators). To portably support n == 0, one has to write the rotate as something like (x << n) | (x >> ((-n) & 31)) And this is apparently not recognized by gcc. Note that this is broken on older GCCs and will result in slower ROL. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-07bitops.h: add sign_extend64()Martin Kepplinger1-0/+11
Months back, this was discussed, see https://lkml.org/lkml/2015/1/18/289 The result was the 64-bit version being "likely fine", "valuable" and "correct". The discussion fell asleep but since there are possible users, let's add it. Signed-off-by: Martin Kepplinger <martin.kepplinger@theobroma-systems.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: George Spelvin <linux@horizon.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Maxime Coquelin <maxime.coquelin@st.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Yury Norov <yury.norov@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-07bitops.h: improve sign_extend32()'s documentationMartin Kepplinger1-0/+2
It is often overlooked that sign_extend32(), despite its name, is safe to use for 16 and 8 bit types as well. This should help prevent sign extension being done manually some other way. Signed-off-by: Martin Kepplinger <martin.kepplinger@theobroma-systems.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: George Spelvin <linux@horizon.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Maxime Coquelin <maxime.coquelin@st.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Yury Norov <yury.norov@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-05linux/bitmap: Force inlining of bitmap weight functionsDenys Vlasenko1-3/+3
With this config: http://busybox.net/~vda/kernel_config_OPTIMIZE_INLINING_and_Os gcc-4.7.2 generates many copies of these tiny functions: bitmap_weight (55 copies): 55 push %rbp 48 89 e5 mov %rsp,%rbp e8 3f 3a 8b 00 callq __bitmap_weight 5d pop %rbp c3 retq hweight_long (23 copies): 55 push %rbp e8 b5 65 8e 00 callq __sw_hweight64 48 89 e5 mov %rsp,%rbp 5d pop %rbp c3 retq See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66122 This patch fixes this via s/inline/__always_inline/ While at it, replaced two "__inline__" with usual "inline" (the rest of the source file uses the latter). text data bss dec filename 86971357 17195880 36659200 140826437 vmlinux.before 86971120 17195912 36659200 140826232 vmlinux Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: David Rientjes <rientjes@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Graf <tgraf@suug.ch> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/1438697716-28121-1-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-17lib: find_*_bit reimplementationYury Norov1-2/+2
This patchset does rework to find_bit function family to achieve better performance, and decrease size of text. All rework is done in patch 1. Patches 2 and 3 are about code moving and renaming. It was boot-tested on x86_64 and MIPS (big-endian) machines. Performance tests were ran on userspace with code like this: /* addr[] is filled from /dev/urandom */ start = clock(); while (ret < nbits) ret = find_next_bit(addr, nbits, ret + 1); end = clock(); printf("%ld\t", (unsigned long) end - start); On Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz measurements are: (for find_next_bit, nbits is 8M, for find_first_bit - 80K) find_next_bit: find_first_bit: new current new current 26932 43151 14777 14925 26947 43182 14521 15423 26507 43824 15053 14705 27329 43759 14473 14777 26895 43367 14847 15023 26990 43693 15103 15163 26775 43299 15067 15232 27282 42752 14544 15121 27504 43088 14644 14858 26761 43856 14699 15193 26692 43075 14781 14681 27137 42969 14451 15061 ... ... find_next_bit performance gain is 35-40%; find_first_bit - no measurable difference. On ARM machine, there is arch-specific implementation for find_bit. Thanks a lot to George Spelvin and Rasmus Villemoes for hints and helpful discussions. This patch (of 3): New implementations takes less space in source file (see diffstat) and in object. For me it's 710 vs 453 bytes of text. It also shows better performance. find_last_bit description fixed due to obvious typo. [akpm@linux-foundation.org: include linux/bitmap.h, per Rasmus] Signed-off-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: George Spelvin <linux@horizon.com> Cc: Alexey Klimov <klimov.linux@gmail.com> Cc: David S. Miller <davem@davemloft.net> Cc: Daniel Borkmann <dborkman@redhat.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Mark Salter <msalter@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Thomas Graf <tgraf@suug.ch> Cc: Valentin Rothberg <valentinrothberg@gmail.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-11-16bitops: Fix shift overflow in GENMASK macrosMaxime COQUELIN1-2/+5
On some 32 bits architectures, including x86, GENMASK(31, 0) returns 0 instead of the expected ~0UL. This is the same on some 64 bits architectures with GENMASK_ULL(63, 0). This is due to an overflow in the shift operand, 1 << 32 for GENMASK, 1 << 64 for GENMASK_ULL. Reported-by: Eric Paire <eric.paire@st.com> Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Maxime Coquelin <maxime.coquelin@st.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> # v3.13+ Cc: linux@rasmusvillemoes.dk Cc: gong.chen@linux.intel.com Cc: John Sullivan <jsrhbz@kanargh.force9.co.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Theodore Ts'o <tytso@mit.edu> Fixes: 10ef6b0dffe4 ("bitops: Introduce a more generic BITMASK macro") Link: http://lkml.kernel.org/r/1415267659-10563-1-git-send-email-maxime.coquelin@st.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-13locking: Remove deprecated smp_mb__() barriersPeter Zijlstra1-20/+0
Its been a while and there are no in-tree users left, so remove the deprecated barriers. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Chen, Gong <gong.chen@linux.intel.com> Cc: Jacob Pan <jacob.jun.pan@linux.intel.com> Cc: Joe Perches <joe@perches.com> Cc: John Sullivan <jsrhbz@kanargh.force9.co.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Cc: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-18arch: Prepare for smp_mb__{before,after}_atomic()Peter Zijlstra1-0/+20
Since the smp_mb__{before,after}*() ops are fundamentally dependent on how an arch can implement atomics it doesn't make sense to have 3 variants of them. They must all be the same. Furthermore, the 3 variants suggest they're only valid for those 3 atomic ops, while we have many more where they could be applied. So move away from smp_mb__{before,after}_{atomic,clear}_{dec,inc,bit}() and reduce the interface to just the two: smp_mb__{before,after}_atomic(). This patch prepares the way by introducing default implementations in asm-generic/barrier.h that default to a full barrier and providing __deprecated inlines for the previous 6 barriers if they're not provided by the arch. This should allow for a mostly painless transition (lots of deprecated warns in the interim). Signed-off-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Link: http://lkml.kernel.org/n/tip-wr59327qdyi9mbzn6x937s4e@git.kernel.org Cc: Arnd Bergmann <arnd@arndb.de> Cc: "Chen, Gong" <gong.chen@linux.intel.com> Cc: John Sullivan <jsrhbz@kanargh.force9.co.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mauro Carvalho Chehab <m.chehab@samsung.com> Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-31ext4: atomically set inode->i_flags in ext4_set_inode_flags()Theodore Ts'o1-0/+15
Use cmpxchg() to atomically set i_flags instead of clearing out the S_IMMUTABLE, S_APPEND, etc. flags and then setting them from the EXT4_IMMUTABLE_FL, EXT4_APPEND_FL flags, since this opens up a race where an immutable file has the immutable flag cleared for a brief window of time. Reported-by: John Sullivan <jsrhbz@kanargh.force9.co.uk> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-14Merge tag 'pm+acpi-3.13-rc1' of ↵Linus Torvalds1-0/+3
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI and power management updates from Rafael J Wysocki: - New power capping framework and the the Intel Running Average Power Limit (RAPL) driver using it from Srinivas Pandruvada and Jacob Pan. - Addition of the in-kernel switching feature to the arm_big_little cpufreq driver from Viresh Kumar and Nicolas Pitre. - cpufreq support for iMac G5 from Aaro Koskinen. - Baytrail processors support for intel_pstate from Dirk Brandewie. - cpufreq support for Midway/ECX-2000 from Mark Langsdorf. - ARM vexpress/TC2 cpufreq support from Sudeep KarkadaNagesha. - ACPI power management support for the I2C and SPI bus types from Mika Westerberg and Lv Zheng. - cpufreq core fixes and cleanups from Viresh Kumar, Srivatsa S Bhat, Stratos Karafotis, Xiaoguang Chen, Lan Tianyu. - cpufreq drivers updates (mostly fixes and cleanups) from Viresh Kumar, Aaro Koskinen, Jungseok Lee, Sudeep KarkadaNagesha, Lukasz Majewski, Manish Badarkhe, Hans-Christian Egtvedt, Evgeny Kapaev. - intel_pstate updates from Dirk Brandewie and Adrian Huang. - ACPICA update to version 20130927 includig fixes and cleanups and some reduction of divergences between the ACPICA code in the kernel and ACPICA upstream in order to improve the automatic ACPICA patch generation process. From Bob Moore, Lv Zheng, Tomasz Nowicki, Naresh Bhat, Bjorn Helgaas, David E Box. - ACPI IPMI driver fixes and cleanups from Lv Zheng. - ACPI hotplug fixes and cleanups from Bjorn Helgaas, Toshi Kani, Zhang Yanfei, Rafael J Wysocki. - Conversion of the ACPI AC driver to the platform bus type and multiple driver fixes and cleanups related to ACPI from Zhang Rui. - ACPI processor driver fixes and cleanups from Hanjun Guo, Jiang Liu, Bartlomiej Zolnierkiewicz, Mathieu Rhéaume, Rafael J Wysocki. - Fixes and cleanups and new blacklist entries related to the ACPI video support from Aaron Lu, Felipe Contreras, Lennart Poettering, Kirill Tkhai. - cpuidle core cleanups from Viresh Kumar and Lorenzo Pieralisi. - cpuidle drivers fixes and cleanups from Daniel Lezcano, Jingoo Han, Bartlomiej Zolnierkiewicz, Prarit Bhargava. - devfreq updates from Sachin Kamat, Dan Carpenter, Manish Badarkhe. - Operation Performance Points (OPP) core updates from Nishanth Menon. - Runtime power management core fix from Rafael J Wysocki and update from Ulf Hansson. - Hibernation fixes from Aaron Lu and Rafael J Wysocki. - Device suspend/resume lockup detection mechanism from Benoit Goby. - Removal of unused proc directories created for various ACPI drivers from Lan Tianyu. - ACPI LPSS driver fix and new device IDs for the ACPI platform scan handler from Heikki Krogerus and Jarkko Nikula. - New ACPI _OSI blacklist entry for Toshiba NB100 from Levente Kurusa. - Assorted fixes and cleanups related to ACPI from Andy Shevchenko, Al Stone, Bartlomiej Zolnierkiewicz, Colin Ian King, Dan Carpenter, Felipe Contreras, Jianguo Wu, Lan Tianyu, Yinghai Lu, Mathias Krause, Liu Chuansheng. - Assorted PM fixes and cleanups from Andy Shevchenko, Thierry Reding, Jean-Christophe Plagniol-Villard. * tag 'pm+acpi-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (386 commits) cpufreq: conservative: fix requested_freq reduction issue ACPI / hotplug: Consolidate deferred execution of ACPI hotplug routines PM / runtime: Use pm_runtime_put_sync() in __device_release_driver() ACPI / event: remove unneeded NULL pointer check Revert "ACPI / video: Ignore BIOS initial backlight value for HP 250 G1" ACPI / video: Quirk initial backlight level 0 ACPI / video: Fix initial level validity test intel_pstate: skip the driver if ACPI has power mgmt option PM / hibernate: Avoid overflow in hibernate_preallocate_memory() ACPI / hotplug: Do not execute "insert in progress" _OST ACPI / hotplug: Carry out PCI root eject directly ACPI / hotplug: Merge device hot-removal routines ACPI / hotplug: Make acpi_bus_hot_remove_device() internal ACPI / hotplug: Simplify device ejection routines ACPI / hotplug: Fix handle_root_bridge_removal() ACPI / hotplug: Refuse to hot-remove all objects with disabled hotplug ACPI / scan: Start matching drivers after trying scan handlers ACPI: Remove acpi_pci_slot_init() headers from internal.h ACPI / blacklist: fix name of ThinkPad Edge E530 PowerCap: Fix build error with option -Werror=format-security ... Conflicts: arch/arm/mach-omap2/opp.c drivers/Kconfig drivers/spi/spi.c
2013-10-22bitops: Introduce a more generic BITMASK macroChen, Gong1-0/+8
GENMASK is used to create a contiguous bitmask([hi:lo]). It is implemented twice in current kernel. One is in EDAC driver, the other is in SiS/XGI FB driver. Move it to a more generic place for other usage. Signed-off-by: Chen, Gong <gong.chen@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Thomas Winischhofer <thomas@winischhofer.net> Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Acked-by: Borislav Petkov <bp@suse.de> Acked-by: Mauro Carvalho Chehab <m.chehab@samsung.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2013-10-17bitops: Introduce BIT_ULLSrinivas Pandruvada1-0/+3
Adding BIT(x) equivalent for unsigned long long type, BIT_ULL(x). Also added BIT_ULL_MASK and BIT_ULL_WORD. Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-03-24bitops: introduce for_each_clear_bit()Akinobu Mita1-0/+11
Introduce for_each_clear_bit() and for_each_clear_bit_from(). They are similar to for_each_set_bit() and list_for_each_set_bit_from(), but they iterate over all the cleared bits in a memory region. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Robert Richter <robert.richter@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Stefano Panella <stefano.panella@csr.com> Cc: David Vrabel <david.vrabel@csr.com> Cc: Sergei Shtylyov <sshtylyov@mvista.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-24bitops: remove for_each_set_bit_cont()Akinobu Mita1-3/+0
Remove for_each_set_bit_cont() after confirming that no one uses for_each_set_bit_cont() anymore. [sfr@canb.auug.org.au: regmap: cope with bitops API change] Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Robert Richter <robert.richter@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-24bitops: rename for_each_set_bit_cont() in favor of analogous list.h functionAkinobu Mita1-1/+4
This renames for_each_set_bit_cont() to for_each_set_bit_from() because it is analogous to list_for_each_entry_from() in list.h rather than list_for_each_entry_continue(). This doesn't remove for_each_set_bit_cont() for now. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Robert Richter <robert.richter@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6Linus Torvalds1-0/+20
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: crypto: sha512 - use standard ror64()
2012-02-16crypto: sha512 - use standard ror64()Alexey Dobriyan1-0/+20
Use standard ror64() instead of hand-written. There is no standard ror64, so create it. The difference is shift value being "unsigned int" instead of uint64_t (for which there is no reason). gcc starts to emit native ROR instructions which it doesn't do for some reason currently. This should make the code faster. Patch survives in-tree crypto test and ping flood with hmac(sha512) on. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-12-06perf, x86: Implement event scheduler helper functionsRobert Richter1-2/+8
This patch introduces x86 perf scheduler code helper functions. We need this to later add more complex functionality to support overlapping counter constraints (next patch). The algorithm is modified so that the range of weight values is now generated from the constraints. There shouldn't be other functional changes. With the helper functions the scheduler is controlled. There are functions to initialize, traverse the event list, find unused counters etc. The scheduler keeps its own state. V3: * Added macro for_each_set_bit_cont(). * Changed functions interfaces of perf_sched_find_counter() and perf_sched_next_event() to use bool as return value. * Added some comments to make code better understandable. V4: * Fix broken event assignment if weight of the first event is not wmin (perf_sched_init()). Signed-off-by: Robert Richter <robert.richter@amd.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1321616122-1533-2-git-send-email-robert.richter@amd.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-27arch: remove CONFIG_GENERIC_FIND_{NEXT_BIT,BIT_LE,LAST_BIT}Akinobu Mita1-2/+0
By the previous style change, CONFIG_GENERIC_FIND_NEXT_BIT, CONFIG_GENERIC_FIND_BIT_LE, and CONFIG_GENERIC_FIND_LAST_BIT are not used to test for existence of find bitops anymore. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Acked-by: Greg Ungerer <gerg@uclinux.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Russell King <linux@arm.linux.org.uk> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-27bitops: add #ifndef for each of find bitopsAkinobu Mita1-0/+2
The style that we normally use in asm-generic is to test the macro itself for existence, so in asm-generic, do: #ifndef find_next_zero_bit_le extern unsigned long find_next_zero_bit_le(const void *addr, unsigned long size, unsigned long offset); #endif and in the architectures, write static inline unsigned long find_next_zero_bit_le(const void *addr, unsigned long size, unsigned long offset) #define find_next_zero_bit_le find_next_zero_bit_le This adds the #ifndef for each of the find bitops in the generic header and source files. Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-15bitops: Provide generic sign_extend32 functionAndreas Herrmann1-0/+11
This patch moves code out from wireless drivers where two different functions are defined in three code locations for the same purpose and provides a common function to sign extend a 32-bit value. Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-10-09bitops: remove duplicated extern declarationsAkinobu Mita1-23/+0
If CONFIG_GENERIC_FIND_NEXT_BIT is enabled, find_next_bit() and find_next_zero_bit() are doubly declared in asm-generic/bitops/find.h and linux/bitops.h. asm/bitops.h includes asm-generic/bitops/find.h if and only if the architecture enables CONFIG_GENERIC_FIND_NEXT_BIT. And asm/bitops.h is included by linux/bitops.h So we can just remove the extern declarations of find_next_bit() and find_next_zero_bit() in linux/bitops.h. Also we can remove unneeded #ifndef CONFIG_GENERIC_FIND_NEXT_BIT in asm-generic/bitops/find.h. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2010-10-09bitops: make asm-generic/bitops/find.h more genericAkinobu Mita1-22/+0
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>
2010-05-18Merge branch 'core-hweight-for-linus' of ↵Linus Torvalds1-25/+5
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-hweight-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, hweight: Use a 32-bit popcnt for __arch_hweight32() arch, hweight: Fix compilation errors x86: Add optimized popcnt variants bitops: Optimize hweight() by making use of compile-time evaluation
2010-05-04arch, hweight: Fix compilation errorsBorislav Petkov1-0/+5
Fix function prototype visibility issues when compiling for non-x86 architectures. Tested with crosstool (ftp://ftp.kernel.org/pub/tools/crosstool/) with alpha, ia64 and sparc targets. Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> LKML-Reference: <20100503130736.GD26107@aftab> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-04-07bitops: remove temporary for_each_bit()Andrew Morton1-3/+0
Migration has been completed so remove this now. There's one straggler in linux-next's drivers/mtd/sm_ftl.c. A patch has been sent. Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-04-07bitops: Optimize hweight() by making use of compile-time evaluationPeter Zijlstra1-25/+0
Rename the extisting runtime hweight() implementations to __arch_hweight(), rename the compile-time versions to __const_hweight() and then have hweight() pick between them. Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <20100318111929.GB11152@aftab> Acked-by: H. Peter Anvin <hpa@zytor.com> LKML-Reference: <1265028224.24455.154.camel@laptop> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-03-06bitops: rename for_each_bit() to for_each_set_bit()Akinobu Mita1-1/+3
Rename for_each_bit to for_each_set_bit in the kernel source tree. To permit for_each_clear_bit(), should that ever be added. The patch includes a macro to map the old for_each_bit() onto the new for_each_set_bit(). This is a (very) temporary thing to ease the migration. [akpm@linux-foundation.org: add temporary for_each_bit()] Suggested-by: Alexey Dobriyan <adobriyan@gmail.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Russell King <rmk@arm.linux.org.uk> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-02-04bitops: Ensure the compile time HWEIGHT is only used for suchPeter Zijlstra1-11/+22
Avoid accidental misuse by failing to compile things Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-29bitops: Provide compile time HWEIGHT{8,16,32,64}Peter Zijlstra1-2/+16
Provide compile time versions of hweight. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> LKML-Reference: <20100122155535.797688466@chello.nl> [ Remove some whitespace damage while we are at it ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-23bitops: Add __ffs64 bitopSteven Whitehouse1-0/+19
Finds the first set bit in a 64 bit word. This is required in order to fix a bug in GFS2, but I think it should be a generic function in case of future users. Signed-off-by: Steven Whitehouse <swhiteho@redhat.com> Reviewed-by: Christoph Lameter <cl@linux.com> Reviewed-by: Willy Tarreau <w@1wt.eu>
2009-01-01bitmap: find_last_bit()Rusty Russell1-1/+12
Impact: New API As the name suggests. For the moment everyone uses the generic one. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-04-29bitops: remove "optimizations"Thomas Gleixner1-103/+12
The mapsize optimizations which were moved from x86 to the generic code in commit 64970b68d2b3ed32b964b0b30b1b98518fde388e increased the binary size on non x86 architectures. Looking into the real effects of the "optimizations" it turned out that they are not used in find_next_bit() and find_next_zero_bit(). The ones in find_first_bit() and find_first_zero_bit() are used in a couple of places but none of them is a real hot path. Remove the "optimizations" all together and call the library functions unconditionally. Boot-tested on x86 and compile tested on every cross compiler I have. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29Avoid divides in BITS_TO_LONGSEric Dumazet1-1/+1
BITS_PER_LONG is a signed value (32 or 64) DIV_ROUND_UP(nr, BITS_PER_LONG) performs signed arithmetic if "nr" is signed too. Converting BITS_TO_LONGS(nr) to DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long)) makes sure compiler can perform a right shift, even if "nr" is a signed value, instead of an expensive integer divide. Applying this patch saves 141 bytes on x86 when CONFIG_CC_OPTIMIZE_FOR_SIZE=y and speedup bitmap operations. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-26x86: optimize find_first_bit for small bitmapsAlexander van Heukelum1-0/+29
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>
2008-04-26x86: generic versions of find_first_(zero_)bit, convert i386Alexander van Heukelum1-0/+34
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>
2008-04-26x86, generic: optimize find_next_(zero_)bit for small constant-size bitmapsAlexander van Heukelum1-0/+77
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>
2008-03-29kernel: add bit rotation helpers for 16 and 8 bitHarvey Harrison1-0/+40
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>
2007-10-19remove BITS_TO_TYPE macroJiri Slaby1-2/+1
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>
2007-10-19define global BIT macroJiri Slaby1-0/+1
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>
2007-10-19define first set of BIT* macrosJiri Slaby1-0/+8
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>
2007-10-16I/OAT: Add support for MSI and MSI-XShannon Nelson1-0/+6
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>
2007-01-27[PATCH] fix various kernel-doc in header filesRobert P. J. Day1-4/+2
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>
2006-03-26[PATCH] bitops: remove unused generic bitops in include/linux/bitops.hAkinobu Mita1-123/+1
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>
2006-03-25[PATCH] roundup_pow_of_two() 64-bit fixAndrew Morton1-0/+7
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>
2006-02-03[PATCH] fix generic_fls64()Akinobu Mita1-1/+1
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>
2006-01-04[FLS64]: generic versionStephen Hemminger1-0/+9
Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-11-15[PATCH] x86-64/i386: Intel HT, Multi core detection fixesSiddha, Suresh B1-0/+10
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>
2005-04-17Linux-2.6.12-rc2Linus Torvalds1-0/+159
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!