1. 23 Nov, 2018 2 commits
  2. 31 Oct, 2018 2 commits
  3. 20 Sep, 2018 1 commit
  4. 02 Aug, 2018 2 commits
  5. 01 Aug, 2018 3 commits
  6. 15 Jun, 2018 1 commit
  7. 14 Jun, 2018 1 commit
  8. 08 Jun, 2018 1 commit
    • Laurent Dufour's avatar
      mm: introduce ARCH_HAS_PTE_SPECIAL · 3010a5ea
      Laurent Dufour authored
      Currently the PTE special supports is turned on in per architecture
      header files.  Most of the time, it is defined in
      arch/*/include/asm/pgtable.h depending or not on some other per
      architecture static definition.
      
      This patch introduce a new configuration variable to manage this
      directly in the Kconfig files.  It would later replace
      __HAVE_ARCH_PTE_SPECIAL.
      
      Here notes for some architecture where the definition of
      __HAVE_ARCH_PTE_SPECIAL is not obvious:
      
      arm
       __HAVE_ARCH_PTE_SPECIAL which is currently defined in
      arch/arm/include/asm/pgtable-3level.h which is included by
      arch/arm/include/asm/pgtable.h when CONFIG_ARM_LPAE is set.
      So select ARCH_HAS_PTE_SPECIAL if ARM_LPAE.
      
      powerpc
      __HAVE_ARCH_PTE_SPECIAL is defined in 2 files:
       - arch/powerpc/include/asm/book3s/64/pgtable.h
       - arch/powerpc/include/asm/pte-common.h
      The first one is included if (PPC_BOOK3S & PPC64) while the second is
      included in all the other cases.
      So select ARCH_HAS_PTE_SPECIAL all the time.
      
      sparc:
      __HAVE_ARCH_PTE_SPECIAL is defined if defined(__sparc__) &&
      defined(__arch64__) which are defined through the compiler in
      sparc/Makefile if !SPARC32 which I assume to be if SPARC64.
      So select ARCH_HAS_PTE_SPECIAL if SPARC64
      
      There is no functional change introduced by this patch.
      
      Link: http://lkml.kernel.org/r/1523433816-14460-2-git-send-email-ldufour@linux.vnet.ibm.com
      
      
      Signed-off-by: default avatarLaurent Dufour <ldufour@linux.vnet.ibm.com>
      Suggested-by: default avatarJerome Glisse <jglisse@redhat.com>
      Reviewed-by: default avatarJerome Glisse <jglisse@redhat.com>
      Acked-by: default avatarDavid Rientjes <rientjes@google.com>
      Cc: Michal Hocko <mhocko@kernel.org>
      Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Cc: Rich Felker <dalias@libc.org>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Palmer Dabbelt <palmer@sifive.com>
      Cc: Albert Ou <albert@sifive.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: David Rientjes <rientjes@google.com>
      Cc: Robin Murphy <robin.murphy@arm.com>
      Cc: Christophe LEROY <christophe.leroy@c-s.fr>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      3010a5ea
  9. 28 May, 2018 1 commit
    • Masahiro Yamada's avatar
      kconfig: reference environment variables directly and remove 'option env=' · 104daea1
      Masahiro Yamada authored
      
      
      To get access to environment variables, Kconfig needs to define a
      symbol using "option env=" syntax.  It is tedious to add a symbol entry
      for each environment variable given that we need to define much more
      such as 'CC', 'AS', 'srctree' etc. to evaluate the compiler capability
      in Kconfig.
      
      Adding '$' for symbol references is grammatically inconsistent.
      Looking at the code, the symbols prefixed with 'S' are expanded by:
       - conf_expand_value()
         This is used to expand 'arch/$ARCH/defconfig' and 'defconfig_list'
       - sym_expand_string_value()
         This is used to expand strings in 'source' and 'mainmenu'
      
      All of them are fixed values independent of user configuration.  So,
      they can be changed into the direct expansion instead of symbols.
      
      This change makes the code much cleaner.  The bounce symbols 'SRCARCH',
      'ARCH', 'SUBARCH', 'KERNELVERSION' are gone.
      
      sym_init() hard-coding 'UNAME_RELEASE' is also gone.  'UNAME_RELEASE'
      should be replaced with an environment variable.
      
      ARCH_DEFCONFIG is a normal symbol, so it should be simply referenced
      without '$' prefix.
      
      The new syntax is addicted by Make.  The variable reference needs
      parentheses, like $(FOO), but you can omit them for single-letter
      variables, like $F.  Yet, in Makefiles, people tend to use the
      parenthetical form for consistency / clarification.
      
      At this moment, only the environment variable is supported, but I will
      extend the concept of 'variable' later on.
      
      The variables are expanded in the lexer so we can simplify the token
      handling on the parser side.
      
      For example, the following code works.
      
      [Example code]
      
        config MY_TOOLCHAIN_LIST
                string
                default "My tools: CC=$(CC), AS=$(AS), CPP=$(CPP)"
      
      [Result]
      
        $ make -s alldefconfig && tail -n 1 .config
        CONFIG_MY_TOOLCHAIN_LIST="My tools: CC=gcc, AS=as, CPP=gcc -E"
      
      Signed-off-by: default avatarMasahiro Yamada <yamada.masahiro@socionext.com>
      Reviewed-by: default avatarKees Cook <keescook@chromium.org>
      104daea1
  10. 11 May, 2018 1 commit
    • Rob Herring's avatar
      sh: switch to NO_BOOTMEM · ac21fc2d
      Rob Herring authored
      Commit 0fa1c579 ("of/fdt: use memblock_virt_alloc for early alloc")
      inadvertently switched the DT unflattening allocations from memblock to
      bootmem which doesn't work because the unflattening happens before
      bootmem is initialized. Swapping the order of bootmem init and
      unflattening could also fix this, but removing bootmem is desired. So
      enable NO_BOOTMEM on SH like other architectures have done.
      
      Fixes: 0fa1c579
      
       ("of/fdt: use memblock_virt_alloc for early alloc")
      Reported-by: default avatarRich Felker <dalias@libc.org>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Signed-off-by: default avatarRob Herring <robh@kernel.org>
      Signed-off-by: default avatarRich Felker <dalias@libc.org>
      ac21fc2d
  11. 09 May, 2018 2 commits
  12. 08 May, 2018 1 commit
  13. 02 Nov, 2017 1 commit
    • Greg Kroah-Hartman's avatar
      License cleanup: add SPDX GPL-2.0 license identifier to files with no license · b2441318
      Greg Kroah-Hartman authored
      
      
      Many source files in the tree are missing licensing information, which
      makes it harder for compliance tools to determine the correct license.
      
      By default all files without license information are under the default
      license of the kernel, which is GPL version 2.
      
      Update the files which contain no license information with the 'GPL-2.0'
      SPDX license identifier.  The SPDX identifier is a legally binding
      shorthand, which can be used instead of the full boiler plate text.
      
      This patch is based on work done by Thomas Gleixner and Kate Stewart and
      Philippe Ombredanne.
      
      How this work was done:
      
      Patches were generated and checked against linux-4.14-rc6 for a subset of
      the use cases:
       - file had no licensing information it it.
       - file was a */uapi/* one with no licensing information in it,
       - file was a */uapi/* one with existing licensing information,
      
      Further patches will be generated in subsequent months to fix up cases
      where non-standard license headers were used, and references to license
      had to be inferred by heuristics based on keywords.
      
      The analysis to determine which SPDX License Identifier to be applied to
      a file was done in a spreadsheet of side by side results from of the
      output of two independent scanners (ScanCode & Windriver) producing SPDX
      tag:value files created by Philippe Ombredanne.  Philippe prepared the
      base worksheet, and did an initial spot review of a few 1000 files.
      
      The 4.13 kernel was the starting point of the analysis with 60,537 files
      assessed.  Kate Stewart did a file by file comparison of the scanner
      results in the spreadsheet to determine which SPDX license identifier(s)
      to be applied to the file. She confirmed any determination that was not
      immediately clear with lawyers working with the Linux Foundation.
      
      Criteria used to select files for SPDX license identifier tagging was:
       - Files considered eligible had to be source code files.
       - Make and config files were included as candidates if they contained >5
         lines of source
       - File already had some variant of a license header in it (even if <5
         lines).
      
      All documentation files were explicitly excluded.
      
      The following heuristics were used to determine which SPDX license
      identifiers to apply.
      
       - when both scanners couldn't find any license traces, file was
         considered to have no license information in it, and the top level
         COPYING file license applied.
      
         For non */uapi/* files that summary was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0                                              11139
      
         and resulted in the first patch in this series.
      
         If that file was a */uapi/* path one, it was "GPL-2.0 WITH
         Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0 WITH Linux-syscall-note                        930
      
         and resulted in the second patch in this series.
      
       - if a file had some form of licensing information in it, and was one
         of the */uapi/* ones, it was denoted with the Linux-syscall-note if
         any GPL family license was found in the file or had no licensing in
         it (per prior point).  Results summary:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|------
         GPL-2.0 WITH Linux-syscall-note                       270
         GPL-2.0+ WITH Linux-syscall-note                      169
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
         LGPL-2.1+ WITH Linux-syscall-note                      15
         GPL-1.0+ WITH Linux-syscall-note                       14
         ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
         LGPL-2.0+ WITH Linux-syscall-note                       4
         LGPL-2.1 WITH Linux-syscall-note                        3
         ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
         ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1
      
         and that resulted in the third patch in this series.
      
       - when the two scanners agreed on the detected license(s), that became
         the concluded license(s).
      
       - when there was disagreement between the two scanners (one detected a
         license but the other didn't, or they both detected different
         licenses) a manual inspection of the file occurred.
      
       - In most cases a manual inspection of the information in the file
         resulted in a clear resolution of the license that should apply (and
         which scanner probably needed to revisit its heuristics).
      
       - When it was not immediately clear, the license identifier was
         confirmed with lawyers working with the Linux Foundation.
      
       - If there was any question as to the appropriate license identifier,
         the file was flagged for further research and to be revisited later
         in time.
      
      In total, over 70 hours of logged manual review was done on the
      spreadsheet to determine the SPDX license identifiers to apply to the
      source files by Kate, Philippe, Thomas and, in some cases, confirmation
      by lawyers working with the Linux Foundation.
      
      Kate also obtained a third independent scan of the 4.13 code base from
      FOSSology, and compared selected files where the other two scanners
      disagreed against that SPDX file, to see if there was new insights.  The
      Windriver scanner is based on an older version of FOSSology in part, so
      they are related.
      
      Thomas did random spot checks in about 500 files from the spreadsheets
      for the uapi headers and agreed with SPDX license identifier in the
      files he inspected. For the non-uapi files Thomas did random spot checks
      in about 15000 files.
      
      In initial set of patches against 4.14-rc6, 3 files were found to have
      copy/paste license identifier errors, and have been fixed to reflect the
      correct identifier.
      
      Additionally Philippe spent 10 hours this week doing a detailed manual
      inspection and review of the 12,461 patched files from the initial patch
      version early this week with:
       - a full scancode scan run, collecting the matched texts, detected
         license ids and scores
       - reviewing anything where there was a license detected (about 500+
         files) to ensure that the applied SPDX license was correct
       - reviewing anything where there was no detection but the patch license
         was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
         SPDX license was correct
      
      This produced a worksheet with 20 files needing minor correction.  This
      worksheet was then exported into 3 different .csv files for the
      different types of files to be modified.
      
      These .csv files were then reviewed by Greg.  Thomas wrote a script to
      parse the csv files and add the proper SPDX tag to the file, in the
      format that the file expected.  This script was further refined by Greg
      based on the output to detect more types of files automatically and to
      distinguish between header and source .c files (which need different
      comment types.)  Finally Greg ran the script using the .csv files to
      generate the patches.
      
      Reviewed-by: default avatarKate Stewart <kstewart@linuxfoundation.org>
      Reviewed-by: default avatarPhilippe Ombredanne <pombredanne@nexb.com>
      Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b2441318
  14. 30 Jun, 2017 1 commit
    • Vladimir Murzin's avatar
      drivers: dma-mapping: allow dma_common_mmap() for NOMMU · 07c75d7a
      Vladimir Murzin authored
      
      
      Currently, internals of dma_common_mmap() is compiled out if build is
      done for either NOMMU or target which explicitly says it does not
      have/want coherent DMA mmap. It turned out that dma_common_mmap() can
      be handy in NOMMU setup (at least for ARM).
      
      This patch converts exitent NOMMU targets to use ARCH_NO_COHERENT_DMA_MMAP,
      thus when CONFIG_MMU is gone from dma_common_mmap() their behaviour stays
      unchanged.
      
      ARM is not converted to ARCH_NO_COHERENT_DMA_MMAP because it 1)
      already has mmap callback which can handle (at some extent) NOMMU 2)
      already defines dummy pgprot_noncached() for NOMMU build.
      
      c6x and frv stay untouched since they already have ARCH_NO_COHERENT_DMA_MMAP.
      
      Cc: Steven Miao <realmz6@gmail.com>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Michal Simek <monstr@monstr.eu>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Cc: Rich Felker <dalias@libc.org>
      Cc: Chris Zankel <chris@zankel.net>
      Cc: Max Filippov <jcmvbkbc@gmail.com>
      Suggested-by: default avatarChristoph Hellwig <hch@lst.de>
      Signed-off-by: Vladimir Murzin's avatarVladimir Murzin <vladimir.murzin@arm.com>
      Tested-by: default avatarBenjamin Gaignard <benjamin.gaignard@linaro.org>
      07c75d7a
  15. 26 Apr, 2017 1 commit
  16. 28 Mar, 2017 1 commit
  17. 05 Aug, 2016 2 commits
    • Rich Felker's avatar
      sh: add SMP support for J2 · b4214e41
      Rich Felker authored
      
      
      Support is hooked up via a cpu start method specified in the device
      tree, and also depends on DT nodes that describe the interfaces for
      performing IPI and identifying which cpu execution is taking place on.
      The currently used method is a form of spin table, where secondary
      cpus are unblocked by writing to a special address.
      
      Signed-off-by: default avatarRich Felker <dalias@libc.org>
      b4214e41
    • Rich Felker's avatar
      sh: add support for J-Core J2 processor · 5a846aba
      Rich Felker authored
      
      
      At the CPU/ISA level, the J2 is compatible with SH-2, and thus the
      changes to add J2 support build on existing SH-2 support. However, J2
      does not duplicate the memory-mapped SH-2 features like the cache
      interface. Instead, the cache interfaces is described in the device
      tree, and new code is added to be able to access the flat device tree
      at early boot before it is unflattened.
      
      Support is also added for receiving interrupts on trap numbers in the
      range 16 to 31, since the J-Core aic1 interrupt controller generates
      these traps. This range was unused but nominally for hardware
      exceptions on SH-2, and a few values in this range were used for
      exceptions on SH-2A, but SH-2A has its own version of the relevant
      code.
      
      No individual cpu subtypes are added for J2 since the intent moving
      forward is to represent SoCs with device tree rather than as
      hard-coded subtypes in the kernel. The CPU_SUBTYPE_J2 Kconfig item
      exists only to fit into the existing cpu selection mechanism until it
      is overhauled.
      
      Signed-off-by: default avatarRich Felker <dalias@libc.org>
      5a846aba
  18. 31 Jul, 2016 3 commits
  19. 08 Jun, 2016 1 commit
    • Linus Walleij's avatar
      sh: do away with ARCH_[WANT_OPTIONAL|REQUIRE]_GPIOLIB · fdcfdfa1
      Linus Walleij authored
      
      
      This replaces:
      
      - "select ARCH_REQUIRE_GPIOLIB" with "select GPIOLIB" as this can
        now be selected directly.
      
      - "select ARCH_WANT_OPTIONAL_GPIOLIB" with no dependency: GPIOLIB
        is now selectable by everyone, so we need not declare our
        intent to select it.
      
      When ordering the symbols the following rationale was used:
      if the selects were in alphabetical order, I moved select GPIOLIB
      to be in alphabetical order, but if the selects were not
      maintained in alphabetical order, I just replaced
      "select ARCH_REQUIRE_GPIOLIB" with "select GPIOLIB".
      
      Cc: Michael Büsch <m@bues.ch>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Cc: Rich Felker <dalias@libc.org>
      Cc: linux-sh@vger.kernel.org
      Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
      fdcfdfa1
  20. 21 May, 2016 3 commits
    • Zhaoxiu Zeng's avatar
      lib/GCD.c: use binary GCD algorithm instead of Euclidean · fff7fb0b
      Zhaoxiu Zeng authored
      
      
      The binary GCD algorithm is based on the following facts:
      	1. If a and b are all evens, then gcd(a,b) = 2 * gcd(a/2, b/2)
      	2. If a is even and b is odd, then gcd(a,b) = gcd(a/2, b)
      	3. If a and b are all odds, then gcd(a,b) = gcd((a-b)/2, b) = gcd((a+b)/2, b)
      
      Even on x86 machines with reasonable division hardware, the binary
      algorithm runs about 25% faster (80% the execution time) than the
      division-based Euclidian algorithm.
      
      On platforms like Alpha and ARMv6 where division is a function call to
      emulation code, it's even more significant.
      
      There are two variants of the code here, depending on whether a fast
      __ffs (find least significant set bit) instruction is available.  This
      allows the unpredictable branches in the bit-at-a-time shifting loop to
      be eliminated.
      
      If fast __ffs is not available, the "even/odd" GCD variant is used.
      
      I use the following code to benchmark:
      
      	#include <stdio.h>
      	#include <stdlib.h>
      	#include <stdint.h>
      	#include <string.h>
      	#include <time.h>
      	#include <unistd.h>
      
      	#define swap(a, b) \
      		do { \
      			a ^= b; \
      			b ^= a; \
      			a ^= b; \
      		} while (0)
      
      	unsigned long gcd0(unsigned long a, unsigned long b)
      	{
      		unsigned long r;
      
      		if (a < b) {
      			swap(a, b);
      		}
      
      		if (b == 0)
      			return a;
      
      		while ((r = a % b) != 0) {
      			a = b;
      			b = r;
      		}
      
      		return b;
      	}
      
      	unsigned long gcd1(unsigned long a, unsigned long b)
      	{
      		unsigned long r = a | b;
      
      		if (!a || !b)
      			return r;
      
      		b >>= __builtin_ctzl(b);
      
      		for (;;) {
      			a >>= __builtin_ctzl(a);
      			if (a == b)
      				return a << __builtin_ctzl(r);
      
      			if (a < b)
      				swap(a, b);
      			a -= b;
      		}
      	}
      
      	unsigned long gcd2(unsigned long a, unsigned long b)
      	{
      		unsigned long r = a | b;
      
      		if (!a || !b)
      			return r;
      
      		r &= -r;
      
      		while (!(b & r))
      			b >>= 1;
      
      		for (;;) {
      			while (!(a & r))
      				a >>= 1;
      			if (a == b)
      				return a;
      
      			if (a < b)
      				swap(a, b);
      			a -= b;
      			a >>= 1;
      			if (a & r)
      				a += b;
      			a >>= 1;
      		}
      	}
      
      	unsigned long gcd3(unsigned long a, unsigned long b)
      	{
      		unsigned long r = a | b;
      
      		if (!a || !b)
      			return r;
      
      		b >>= __builtin_ctzl(b);
      		if (b == 1)
      			return r & -r;
      
      		for (;;) {
      			a >>= __builtin_ctzl(a);
      			if (a == 1)
      				return r & -r;
      			if (a == b)
      				return a << __builtin_ctzl(r);
      
      			if (a < b)
      				swap(a, b);
      			a -= b;
      		}
      	}
      
      	unsigned long gcd4(unsigned long a, unsigned long b)
      	{
      		unsigned long r = a | b;
      
      		if (!a || !b)
      			return r;
      
      		r &= -r;
      
      		while (!(b & r))
      			b >>= 1;
      		if (b == r)
      			return r;
      
      		for (;;) {
      			while (!(a & r))
      				a >>= 1;
      			if (a == r)
      				return r;
      			if (a == b)
      				return a;
      
      			if (a < b)
      				swap(a, b);
      			a -= b;
      			a >>= 1;
      			if (a & r)
      				a += b;
      			a >>= 1;
      		}
      	}
      
      	static unsigned long (*gcd_func[])(unsigned long a, unsigned long b) = {
      		gcd0, gcd1, gcd2, gcd3, gcd4,
      	};
      
      	#define TEST_ENTRIES (sizeof(gcd_func) / sizeof(gcd_func[0]))
      
      	#if defined(__x86_64__)
      
      	#define rdtscll(val) do { \
      		unsigned long __a,__d; \
      		__asm__ __volatile__("rdtsc" : "=a" (__a), "=d" (__d)); \
      		(val) = ((unsigned long long)__a) | (((unsigned long long)__d)<<32); \
      	} while(0)
      
      	static unsigned long long benchmark_gcd_func(unsigned long (*gcd)(unsigned long, unsigned long),
      								unsigned long a, unsigned long b, unsigned long *res)
      	{
      		unsigned long long start, end;
      		unsigned long long ret;
      		unsigned long gcd_res;
      
      		rdtscll(start);
      		gcd_res = gcd(a, b);
      		rdtscll(end);
      
      		if (end >= start)
      			ret = end - start;
      		else
      			ret = ~0ULL - start + 1 + end;
      
      		*res = gcd_res;
      		return ret;
      	}
      
      	#else
      
      	static inline struct timespec read_time(void)
      	{
      		struct timespec time;
      		clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &time);
      		return time;
      	}
      
      	static inline unsigned long long diff_time(struct timespec start, struct timespec end)
      	{
      		struct timespec temp;
      
      		if ((end.tv_nsec - start.tv_nsec) < 0) {
      			temp.tv_sec = end.tv_sec - start.tv_sec - 1;
      			temp.tv_nsec = 1000000000ULL + end.tv_nsec - start.tv_nsec;
      		} else {
      			temp.tv_sec = end.tv_sec - start.tv_sec;
      			temp.tv_nsec = end.tv_nsec - start.tv_nsec;
      		}
      
      		return temp.tv_sec * 1000000000ULL + temp.tv_nsec;
      	}
      
      	static unsigned long long benchmark_gcd_func(unsigned long (*gcd)(unsigned long, unsigned long),
      								unsigned long a, unsigned long b, unsigned long *res)
      	{
      		struct timespec start, end;
      		unsigned long gcd_res;
      
      		start = read_time();
      		gcd_res = gcd(a, b);
      		end = read_time();
      
      		*res = gcd_res;
      		return diff_time(start, end);
      	}
      
      	#endif
      
      	static inline unsigned long get_rand()
      	{
      		if (sizeof(long) == 8)
      			return (unsigned long)rand() << 32 | rand();
      		else
      			return rand();
      	}
      
      	int main(int argc, char **argv)
      	{
      		unsigned int seed = time(0);
      		int loops = 100;
      		int repeats = 1000;
      		unsigned long (*res)[TEST_ENTRIES];
      		unsigned long long elapsed[TEST_ENTRIES];
      		int i, j, k;
      
      		for (;;) {
      			int opt = getopt(argc, argv, "n:r:s:");
      			/* End condition always first */
      			if (opt == -1)
      				break;
      
      			switch (opt) {
      			case 'n':
      				loops = atoi(optarg);
      				break;
      			case 'r':
      				repeats = atoi(optarg);
      				break;
      			case 's':
      				seed = strtoul(optarg, NULL, 10);
      				break;
      			default:
      				/* You won't actually get here. */
      				break;
      			}
      		}
      
      		res = malloc(sizeof(unsigned long) * TEST_ENTRIES * loops);
      		memset(elapsed, 0, sizeof(elapsed));
      
      		srand(seed);
      		for (j = 0; j < loops; j++) {
      			unsigned long a = get_rand();
      			/* Do we have args? */
      			unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand();
      			unsigned long long min_elapsed[TEST_ENTRIES];
      			for (k = 0; k < repeats; k++) {
      				for (i = 0; i < TEST_ENTRIES; i++) {
      					unsigned long long tmp = benchmark_gcd_func(gcd_func[i], a, b, &res[j][i]);
      					if (k == 0 || min_elapsed[i] > tmp)
      						min_elapsed[i] = tmp;
      				}
      			}
      			for (i = 0; i < TEST_ENTRIES; i++)
      				elapsed[i] += min_elapsed[i];
      		}
      
      		for (i = 0; i < TEST_ENTRIES; i++)
      			printf("gcd%d: elapsed %llu\n", i, elapsed[i]);
      
      		k = 0;
      		srand(seed);
      		for (j = 0; j < loops; j++) {
      			unsigned long a = get_rand();
      			unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand();
      			for (i = 1; i < TEST_ENTRIES; i++) {
      				if (res[j][i] != res[j][0])
      					break;
      			}
      			if (i < TEST_ENTRIES) {
      				if (k == 0) {
      					k = 1;
      					fprintf(stderr, "Error:\n");
      				}
      				fprintf(stderr, "gcd(%lu, %lu): ", a, b);
      				for (i = 0; i < TEST_ENTRIES; i++)
      					fprintf(stderr, "%ld%s", res[j][i], i < TEST_ENTRIES - 1 ? ", " : "\n");
      			}
      		}
      
      		if (k == 0)
      			fprintf(stderr, "PASS\n");
      
      		free(res);
      
      		return 0;
      	}
      
      Compiled with "-O2", on "VirtualBox 4.4.0-22-generic #38-Ubuntu x86_64" got:
      
        zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
        gcd0: elapsed 10174
        gcd1: elapsed 2120
        gcd2: elapsed 2902
        gcd3: elapsed 2039
        gcd4: elapsed 2812
        PASS
        zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
        gcd0: elapsed 9309
        gcd1: elapsed 2280
        gcd2: elapsed 2822
        gcd3: elapsed 2217
        gcd4: elapsed 2710
        PASS
        zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
        gcd0: elapsed 9589
        gcd1: elapsed 2098
        gcd2: elapsed 2815
        gcd3: elapsed 2030
        gcd4: elapsed 2718
        PASS
        zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10
        gcd0: elapsed 9914
        gcd1: elapsed 2309
        gcd2: elapsed 2779
        gcd3: elapsed 2228
        gcd4: elapsed 2709
        PASS
      
      [akpm@linux-foundation.org: avoid #defining a CONFIG_ variable]
      Signed-off-by: default avatarZhaoxiu Zeng <zhaoxiu.zeng@gmail.com>
      Signed-off-by: default avatarGeorge Spelvin <linux@horizon.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      fff7fb0b
    • Petr Mladek's avatar
      printk/nmi: generic solution for safe printk in NMI · 42a0bb3f
      Petr Mladek authored
      printk() takes some locks and could not be used a safe way in NMI
      context.
      
      The chance of a deadlock is real especially when printing stacks from
      all CPUs.  This particular problem has been addressed on x86 by the
      commit a9edc880 ("x86/nmi: Perform a safe NMI stack trace on all
      CPUs").
      
      The patchset brings two big advantages.  First, it makes the NMI
      backtraces safe on all architectures for free.  Second, it makes all NMI
      messages almost safe on all architectures (the temporary buffer is
      limited.  We still should keep the number of messages in NMI context at
      minimum).
      
      Note that there already are several messages printed in NMI context:
      WARN_ON(in_nmi()), BUG_ON(in_nmi()), anything being printed out from MCE
      handlers.  These are not easy to avoid.
      
      This patch reuses most of the code and makes it generic.  It is useful
      for all messages and architectures that support NMI.
      
      The alternative printk_func is set when entering and is reseted when
      leaving NMI context.  It queues IRQ work to copy the messages into the
      main ring buffer in a safe context.
      
      __printk_nmi_flush() copies all available messages and reset the buffer.
      Then we could use a simple cmpxchg operations to get synchronized with
      writers.  There is also used a spinlock to get synchronized with other
      flushers.
      
      We do not longer use seq_buf because it depends on external lock.  It
      would be hard to make all supported operations safe for a lockless use.
      It would be confusing and error prone to make only some operations safe.
      
      The code is put into separate printk/nmi.c as suggested by Steven
      Rostedt.  It needs a per-CPU buffer and is compiled only on
      architectures that call nmi_enter().  This is achieved by the new
      HAVE_NMI Kconfig flag.
      
      The are MN10300 and Xtensa architectures.  We need to clean up NMI
      handling there first.  Let's do it separately.
      
      The patch is heavily based on the draft from Peter Zijlstra, see
      
        https://lkml.org/lkml/2015/6/10/327
      
      
      
      [arnd@arndb.de: printk-nmi: use %zu format string for size_t]
      [akpm@linux-foundation.org: min_t->min - all types are size_t here]
      Signed-off-by: default avatarPetr Mladek <pmladek@suse.com>
      Suggested-by: default avatarPeter Zijlstra <peterz@infradead.org>
      Suggested-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Cc: Jan Kara <jack@suse.cz>
      Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>	[arm part]
      Cc: Daniel Thompson <daniel.thompson@linaro.org>
      Cc: Jiri Kosina <jkosina@suse.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: David Miller <davem@davemloft.net>
      Cc: Daniel Thompson <daniel.thompson@linaro.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      42a0bb3f
    • Jiri Slaby's avatar
      exit_thread: remove empty bodies · 5f56a5df
      Jiri Slaby authored
      
      
      Define HAVE_EXIT_THREAD for archs which want to do something in
      exit_thread. For others, let's define exit_thread as an empty inline.
      
      This is a cleanup before we change the prototype of exit_thread to
      accept a task parameter.
      
      [akpm@linux-foundation.org: fix mips]
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
      Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Chen Liqin <liqin.linux@gmail.com>
      Cc: Chris Metcalf <cmetcalf@mellanox.com>
      Cc: Chris Zankel <chris@zankel.net>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
      Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
      Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Helge Deller <deller@gmx.de>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      Cc: James Hogan <james.hogan@imgtec.com>
      Cc: Jeff Dike <jdike@addtoit.com>
      Cc: Jesper Nilsson <jesper.nilsson@axis.com>
      Cc: Jiri Slaby <jslaby@suse.cz>
      Cc: Jonas Bonn <jonas@southpole.se>
      Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
      Cc: Lennox Wu <lennox.wu@gmail.com>
      Cc: Ley Foon Tan <lftan@altera.com>
      Cc: Mark Salter <msalter@redhat.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Matt Turner <mattst88@gmail.com>
      Cc: Max Filippov <jcmvbkbc@gmail.com>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Michal Simek <monstr@monstr.eu>
      Cc: Mikael Starvik <starvik@axis.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Rich Felker <dalias@libc.org>
      Cc: Richard Henderson <rth@twiddle.net>
      Cc: Richard Kuo <rkuo@codeaurora.org>
      Cc: Richard Weinberger <richard@nod.at>
      Cc: Russell King <linux@arm.linux.org.uk>
      Cc: Steven Miao <realmz6@gmail.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      5f56a5df
  21. 17 Mar, 2016 1 commit
  22. 08 Mar, 2016 2 commits
    • Bjorn Helgaas's avatar
      PCI: Include pci/hotplug Kconfig directly from pci/Kconfig · e7e127e3
      Bjorn Helgaas authored
      
      
      Include pci/hotplug/Kconfig directly from pci/Kconfig, so arches don't
      have to source both pci/Kconfig and pci/hotplug/Kconfig.
      
      Note that this effectively adds pci/hotplug/Kconfig to the following
      arches, because they already sourced drivers/pci/Kconfig but they
      previously did not source drivers/pci/hotplug/Kconfig:
      
        alpha
        arm
        avr32
        frv
        m68k
        microblaze
        mn10300
        sparc
        unicore32
      
      Inspired-by-patch-from: Bogicevic Sasa <brutallesale@gmail.com>
      Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
      e7e127e3
    • Bogicevic Sasa's avatar
      PCI: Include pci/pcie/Kconfig directly from pci/Kconfig · 5f8fc432
      Bogicevic Sasa authored
      
      
      Include pci/pcie/Kconfig directly from pci/Kconfig, so arches don't
      have to source both pci/Kconfig and pci/pcie/Kconfig.
      
      Note that this effectively adds pci/pcie/Kconfig to the following
      arches, because they already sourced drivers/pci/Kconfig but they
      previously did not source drivers/pci/pcie/Kconfig:
      
        alpha
        avr32
        blackfin
        frv
        m32r
        m68k
        microblaze
        mn10300
        parisc
        sparc
        unicore32
        xtensa
      
      [bhelgaas: changelog, source pci/pcie/Kconfig at top of pci/Kconfig, whitespace]
      Signed-off-by: default avatarSasa Bogicevic <brutallesale@gmail.com>
      Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
      5f8fc432
  23. 21 Jan, 2016 1 commit
    • Christoph Hellwig's avatar
      dma-mapping: always provide the dma_map_ops based implementation · e1c7e324
      Christoph Hellwig authored
      
      
      Move the generic implementation to <linux/dma-mapping.h> now that all
      architectures support it and remove the HAVE_DMA_ATTR Kconfig symbol now
      that everyone supports them.
      
      [valentinrothberg@gmail.com: remove leftovers in Kconfig]
      Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
      Cc: Chris Metcalf <cmetcalf@ezchip.com>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
      Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
      Cc: Helge Deller <deller@gmx.de>
      Cc: James Hogan <james.hogan@imgtec.com>
      Cc: Jesper Nilsson <jesper.nilsson@axis.com>
      Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
      Cc: Ley Foon Tan <lftan@altera.com>
      Cc: Mark Salter <msalter@redhat.com>
      Cc: Mikael Starvik <starvik@axis.com>
      Cc: Steven Miao <realmz6@gmail.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Christian Borntraeger <borntraeger@de.ibm.com>
      Cc: Joerg Roedel <jroedel@suse.de>
      Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
      Signed-off-by: default avatarValentin Rothberg <valentinrothberg@gmail.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      e1c7e324
  24. 16 Jan, 2016 1 commit
  25. 10 Sep, 2015 1 commit
    • Dave Young's avatar
      kexec: split kexec_load syscall from kexec core code · 2965faa5
      Dave Young authored
      
      
      There are two kexec load syscalls, kexec_load another and kexec_file_load.
       kexec_file_load has been splited as kernel/kexec_file.c.  In this patch I
      split kexec_load syscall code to kernel/kexec.c.
      
      And add a new kconfig option KEXEC_CORE, so we can disable kexec_load and
      use kexec_file_load only, or vice verse.
      
      The original requirement is from Ted Ts'o, he want kexec kernel signature
      being checked with CONFIG_KEXEC_VERIFY_SIG enabled.  But kexec-tools use
      kexec_load syscall can bypass the checking.
      
      Vivek Goyal proposed to create a common kconfig option so user can compile
      in only one syscall for loading kexec kernel.  KEXEC/KEXEC_FILE selects
      KEXEC_CORE so that old config files still work.
      
      Because there's general code need CONFIG_KEXEC_CORE, so I updated all the
      architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects
      KEXEC_CORE in arch Kconfig.  Also updated general kernel code with to
      kexec_load syscall.
      
      [akpm@linux-foundation.org: coding-style fixes]
      Signed-off-by: default avatarDave Young <dyoung@redhat.com>
      Cc: Eric W. Biederman <ebiederm@xmission.com>
      Cc: Vivek Goyal <vgoyal@redhat.com>
      Cc: Petr Tesarik <ptesarik@suse.cz>
      Cc: Theodore Ts'o <tytso@mit.edu>
      Cc: Josh Boyer <jwboyer@fedoraproject.org>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      2965faa5
  26. 14 Apr, 2015 1 commit
  27. 10 Feb, 2015 1 commit
  28. 19 Dec, 2014 1 commit