1. 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
  2. 09 Sep, 2017 1 commit
    • Alexey Dobriyan's avatar
      cpumask: make cpumask_next() out-of-line · f22ef333
      Alexey Dobriyan authored
      Every for_each_XXX_cpu() invocation calls cpumask_next() which is an
      inline function:
      
      	static inline unsigned int cpumask_next(int n, const struct cpumask *srcp)
      	{
      	        /* -1 is a legal arg here. */
      	        if (n != -1)
      	                cpumask_check(n);
      	        return find_next_bit(cpumask_bits(srcp), nr_cpumask_bits, n + 1);
      	}
      
      However!
      
      find_next_bit() is regular out-of-line function which means "nr_cpu_ids"
      load and increment happen at the caller resulting in a lot of bloat
      
      x86_64 defconfig:
      	add/remove: 3/0 grow/shrink: 8/373 up/down: 155/-5668 (-5513)
      x86_64 allyesconfig-ish:
      	add/remove: 3/1 grow/shrink: 57/634 up/down: 3515/-28177 (-24662) !!!
      
      Some archs redefine find_next_bit() but it is OK:
      
      	m68k		inline but SMP is not supported
      	arm		out-of-line
      	unicore32	out-of-line
      
      Function call will happen anyway, so move load and increment into callee.
      
      Link: http://lkml.kernel.org/r/20170824230010.GA1593@avx2Signed-off-by: default avatarAlexey Dobriyan <adobriyan@gmail.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      f22ef333
  3. 15 May, 2017 1 commit
  4. 08 Mar, 2016 1 commit
  5. 29 Feb, 2016 1 commit
  6. 19 Jun, 2015 1 commit
  7. 28 May, 2015 1 commit
    • Rusty Russell's avatar
      cpumask_set_cpu_local_first => cpumask_local_spread, lament · f36963c9
      Rusty Russell authored
      da91309e (cpumask: Utility function to set n'th cpu...) created a
      genuinely weird function.  I never saw it before, it went through DaveM.
      (He only does this to make us other maintainers feel better about our own
      mistakes.)
      
      cpumask_set_cpu_local_first's purpose is say "I need to spread things
      across N online cpus, choose the ones on this numa node first"; you call
      it in a loop.
      
      It can fail.  One of the two callers ignores this, the other aborts and
      fails the device open.
      
      It can fail in two ways: allocating the off-stack cpumask, or through a
      convoluted codepath which AFAICT can only occur if cpu_online_mask
      changes.  Which shouldn't happen, because if cpu_online_mask can change
      while you call this, it could return a now-offline cpu anyway.
      
      It contains a nonsensical test "!cpumask_of_node(numa_node)".  This was
      drawn to my attention by Geert, who said this causes a warning on Sparc.
      It sets a single bit in a cpumask instead of returning a cpu number,
      because that's what the callers want.
      
      It could be made more efficient by passing the previous cpu rather than
      an index, but that would be more invasive to the callers.
      
      Fixes: da91309e
      Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (then rebased)
      Tested-by: default avatarAmir Vadai <amirv@mellanox.com>
      Acked-by: default avatarAmir Vadai <amirv@mellanox.com>
      Acked-by: default avatarDavid S. Miller <davem@davemloft.net>
      f36963c9
  8. 19 Apr, 2015 1 commit
  9. 17 Apr, 2015 1 commit
  10. 10 Mar, 2015 1 commit
  11. 03 Jul, 2014 1 commit
  12. 11 Jun, 2014 1 commit
    • Amir Vadai's avatar
      cpumask: Utility function to set n'th cpu - local cpu first · da91309e
      Amir Vadai authored
      This function sets the n'th cpu - local cpu's first.
      For example: in a 16 cores server with even cpu's local, will get the
      following values:
      cpumask_set_cpu_local_first(0, numa, cpumask) => cpu 0 is set
      cpumask_set_cpu_local_first(1, numa, cpumask) => cpu 2 is set
      ...
      cpumask_set_cpu_local_first(7, numa, cpumask) => cpu 14 is set
      cpumask_set_cpu_local_first(8, numa, cpumask) => cpu 1 is set
      cpumask_set_cpu_local_first(9, numa, cpumask) => cpu 3 is set
      ...
      cpumask_set_cpu_local_first(15, numa, cpumask) => cpu 15 is set
      
      Curently this function will be used by multi queue networking devices to
      calculate the irq affinity mask, such that as many local cpu's as
      possible will be utilized to handle the mq device irq's.
      Signed-off-by: default avatarAmir Vadai <amirv@mellanox.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      da91309e
  13. 02 Jun, 2014 2 commits
    • David S. Miller's avatar
      net: Revert mlx4 cpumask changes. · ee39facb
      David S. Miller authored
      This reverts commit 70a640d0
      ("net/mlx4_en: Use affinity hint") and commit
      c8865b64 ("cpumask: Utility function
      to set n'th cpu - local cpu first") because these changes break
      the build when SMP is disabled amongst other things.
      Reported-by: default avatarEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      ee39facb
    • Amir Vadai's avatar
      cpumask: Utility function to set n'th cpu - local cpu first · c8865b64
      Amir Vadai authored
      This function sets the n'th cpu - local cpu's first.
      For example: in a 16 cores server with even cpu's local, will get the
      following values:
      cpumask_set_cpu_local_first(0, numa, cpumask) => cpu 0 is set
      cpumask_set_cpu_local_first(1, numa, cpumask) => cpu 2 is set
      ...
      cpumask_set_cpu_local_first(7, numa, cpumask) => cpu 14 is set
      cpumask_set_cpu_local_first(8, numa, cpumask) => cpu 1 is set
      cpumask_set_cpu_local_first(9, numa, cpumask) => cpu 3 is set
      ...
      cpumask_set_cpu_local_first(15, numa, cpumask) => cpu 15 is set
      
      Curently this function will be used by multi queue networking devices to
      calculate the irq affinity mask, such that as many local cpu's as
      possible will be utilized to handle the mq device irq's.
      Signed-off-by: default avatarAmir Vadai <amirv@mellanox.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      c8865b64
  14. 22 Jan, 2014 1 commit
    • Santosh Shilimkar's avatar
      lib/cpumask.c: use memblock apis for early memory allocations · c1529500
      Santosh Shilimkar authored
      Switch to memblock interfaces for early memory allocator instead of
      bootmem allocator.  No functional change in beahvior than what it is in
      current code from bootmem users points of view.
      
      Archs already converted to NO_BOOTMEM now directly use memblock
      interfaces instead of bootmem wrappers build on top of memblock.  And
      the archs which still uses bootmem, these new apis just fallback to
      exiting bootmem APIs.
      Signed-off-by: default avatarSantosh Shilimkar <santosh.shilimkar@ti.com>
      Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Christoph Lameter <cl@linux-foundation.org>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Grygorii Strashko <grygorii.strashko@ti.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      Cc: Michal Hocko <mhocko@suse.cz>
      Cc: Paul Walmsley <paul@pwsan.com>
      Cc: Pavel Machek <pavel@ucw.cz>
      Cc: Russell King <linux@arm.linux.org.uk>
      Cc: Tejun Heo <tj@kernel.org>
      Cc: Tony Lindgren <tony@atomide.com>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      c1529500
  15. 12 Dec, 2012 1 commit
    • Joonsoo Kim's avatar
      bootmem: fix wrong call parameter for free_bootmem() · 81df9bff
      Joonsoo Kim authored
      It is strange that alloc_bootmem() returns a virtual address and
      free_bootmem() requires a physical address.  Anyway, free_bootmem()'s
      first parameter should be physical address.
      
      There are some call sites for free_bootmem() with virtual address.  So fix
      them.
      
      [akpm@linux-foundation.org: improve free_bootmem() and free_bootmem_pate() documentation]
      Signed-off-by: default avatarJoonsoo Kim <js1304@gmail.com>
      Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
      Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      81df9bff
  16. 29 Mar, 2012 1 commit
  17. 07 Mar, 2012 1 commit
  18. 26 Jul, 2011 2 commits
  19. 30 Mar, 2010 1 commit
    • Tejun Heo's avatar
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      Tejun Heo authored
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
      
      percpu.h is included by sched.h and module.h and thus ends up being
      included when building most .c files.  percpu.h includes slab.h which
      in turn includes gfp.h making everything defined by the two files
      universally available and complicating inclusion dependencies.
      
      percpu.h -> slab.h dependency is about to be removed.  Prepare for
      this change by updating users of gfp and slab facilities include those
      headers directly instead of assuming availability.  As this conversion
      needs to touch large number of source files, the following script is
      used as the basis of conversion.
      
        http://userweb.kernel.org/~tj/misc/slabh-sweep.py
      
      The script does the followings.
      
      * Scan files for gfp and slab usages and update includes such that
        only the necessary includes are there.  ie. if only gfp is used,
        gfp.h, if slab is used, slab.h.
      
      * When the script inserts a new include, it looks at the include
        blocks and try to put the new include such that its order conforms
        to its surrounding.  It's put in the include block which contains
        core kernel includes, in the same order that the rest are ordered -
        alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
        doesn't seem to be any matching order.
      
      * If the script can't find a place to put a new include (mostly
        because the file doesn't have fitting include block), it prints out
        an error message indicating which .h file needs to be added to the
        file.
      
      The conversion was done in the following steps.
      
      1. The initial automatic conversion of all .c files updated slightly
         over 4000 files, deleting around 700 includes and adding ~480 gfp.h
         and ~3000 slab.h inclusions.  The script emitted errors for ~400
         files.
      
      2. Each error was manually checked.  Some didn't need the inclusion,
         some needed manual addition while adding it to implementation .h or
         embedding .c file was more appropriate for others.  This step added
         inclusions to around 150 files.
      
      3. The script was run again and the output was compared to the edits
         from #2 to make sure no file was left behind.
      
      4. Several build tests were done and a couple of problems were fixed.
         e.g. lib/decompress_*.c used malloc/free() wrappers around slab
         APIs requiring slab.h to be added manually.
      
      5. The script was run on all .h files but without automatically
         editing them as sprinkling gfp.h and slab.h inclusions around .h
         files could easily lead to inclusion dependency hell.  Most gfp.h
         inclusion directives were ignored as stuff from gfp.h was usually
         wildly available and often used in preprocessor macros.  Each
         slab.h inclusion directive was examined and added manually as
         necessary.
      
      6. percpu.h was updated not to include slab.h.
      
      7. Build test were done on the following configurations and failures
         were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
         distributed build env didn't work with gcov compiles) and a few
         more options had to be turned off depending on archs to make things
         build (like ipr on powerpc/64 which failed due to missing writeq).
      
         * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
         * powerpc and powerpc64 SMP allmodconfig
         * sparc and sparc64 SMP allmodconfig
         * ia64 SMP allmodconfig
         * s390 SMP allmodconfig
         * alpha SMP allmodconfig
         * um on x86_64 SMP allmodconfig
      
      8. percpu.h modifications were reverted so that it could be applied as
         a separate patch and serve as bisection point.
      
      Given the fact that I had only a couple of failures from tests on step
      6, I'm fairly confident about the coverage of this conversion patch.
      If there is a breakage, it's likely to be something in one of the arch
      headers which should be easily discoverable easily on most builds of
      the specific arch.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Guess-its-ok-by: default avatarChristoph Lameter <cl@linux-foundation.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  20. 11 Jun, 2009 1 commit
  21. 09 Jun, 2009 1 commit
  22. 03 Apr, 2009 1 commit
  23. 31 Dec, 2008 2 commits
  24. 19 Dec, 2008 2 commits
    • Mike Travis's avatar
      cpumask: documentation for cpumask_var_t · ec26b805
      Mike Travis authored
      Impact: New kerneldoc comments
      
      Additional documentation added to all the alloc_cpumask and free_cpumask
      functions.
      Signed-off-by: default avatarMike Travis <travis@sgi.com>
      Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (minor additions)
      ec26b805
    • Mike Travis's avatar
      cpumask: Add alloc_cpumask_var_node() · 7b4967c5
      Mike Travis authored
      Impact: New API
      
      This will be needed in x86 code to allocate the domain and old_domain
      cpumasks on the same node as where the containing irq_cfg struct is
      allocated.
      
      (Also fixes double-dump_stack on rare CONFIG_DEBUG_PER_CPU_MAPS case)
      Signed-off-by: default avatarMike Travis <travis@sgi.com>
      Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (re-impl alloc_cpumask_var)
      7b4967c5
  25. 09 Nov, 2008 1 commit
  26. 07 Nov, 2008 1 commit
  27. 06 Nov, 2008 1 commit
    • Rusty Russell's avatar
      cpumask: introduce new API, without changing anything · 2d3854a3
      Rusty Russell authored
      Impact: introduce new APIs
      
      We want to deprecate cpumasks on the stack, as we are headed for
      gynormous numbers of CPUs.  Eventually, we want to head towards an
      undefined 'struct cpumask' so they can never be declared on stack.
      
      1) New cpumask functions which take pointers instead of copies.
         (cpus_* -> cpumask_*)
      
      2) Several new helpers to reduce requirements for temporary cpumasks
         (cpumask_first_and, cpumask_next_and, cpumask_any_and)
      
      3) Helpers for declaring cpumasks on or offstack for large NR_CPUS
         (cpumask_var_t, alloc_cpumask_var and free_cpumask_var)
      
      4) 'struct cpumask' for explicitness and to mark new-style code.
      
      5) Make iterator functions stop at nr_cpu_ids (a runtime constant),
         not NR_CPUS for time efficiency and for smaller dynamic allocations
         in future.
      
      6) cpumask_copy() so we can allocate less than a full cpumask eventually
         (for alloc_cpumask_var), and so we can eliminate the 'struct cpumask'
         definition eventually.
      
      7) work_on_cpu() helper for doing task on a CPU, rather than saving old
         cpumask for current thread and manipulating it.
      
      8) smp_call_function_many() which is smp_call_function_mask() except
         taking a cpumask pointer.
      
      Note that this patch simply introduces the new functions and leaves
      the obsolescent ones in place.  This is to simplify the transition
      patches.
      Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      2d3854a3
  28. 23 May, 2008 1 commit
    • Mike Travis's avatar
      x86: Add performance variants of cpumask operators · 41df0d61
      Mike Travis authored
        * Increase performance for systems with large count NR_CPUS by limiting
          the range of the cpumask operators that loop over the bits in a cpumask_t
          variable.  This removes a large amount of wasted cpu cycles.
      
        * Add performance variants of the cpumask operators:
      
          int cpus_weight_nr(mask)	     Same using nr_cpu_ids instead of NR_CPUS
          int first_cpu_nr(mask)	     Number lowest set bit, or nr_cpu_ids
          int next_cpu_nr(cpu, mask)	     Next cpu past 'cpu', or nr_cpu_ids
          for_each_cpu_mask_nr(cpu, mask)  for-loop cpu over mask using nr_cpu_ids
      
        * Modify following to use performance variants:
      
          #define num_online_cpus()	cpus_weight_nr(cpu_online_map)
          #define num_possible_cpus()	cpus_weight_nr(cpu_possible_map)
          #define num_present_cpus()	cpus_weight_nr(cpu_present_map)
      
          #define for_each_possible_cpu(cpu) for_each_cpu_mask_nr((cpu), ...)
          #define for_each_online_cpu(cpu)   for_each_cpu_mask_nr((cpu), ...)
          #define for_each_present_cpu(cpu)  for_each_cpu_mask_nr((cpu), ...)
      
        * Comment added to include/linux/cpumask.h:
      
          Note: The alternate operations with the suffix "_nr" are used
      	  to limit the range of the loop to nr_cpu_ids instead of
      	  NR_CPUS when NR_CPUS > 64 for performance reasons.
      	  If NR_CPUS is <= 64 then most assembler bitmask
      	  operators execute faster with a constant range, so
      	  the operator will continue to use NR_CPUS.
      
      	  Another consideration is that nr_cpu_ids is initialized
      	  to NR_CPUS and isn't lowered until the possible cpus are
      	  discovered (including any disabled cpus).  So early uses
      	  will span the entire range of NR_CPUS.
      
          (The net effect is that for systems with 64 or less CPU's there are no
           functional changes.)
      
      For inclusion into sched-devel/latest tree.
      
      Based on:
      	git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
          +   sched-devel/latest  .../mingo/linux-2.6-sched-devel.git
      
      Cc: Paul Jackson <pj@sgi.com>
      Cc: Christoph Lameter <clameter@sgi.com>
      Reviewed-by: default avatarPaul Jackson <pj@sgi.com>
      Reviewed-by: default avatarChristoph Lameter <clameter@sgi.com>
      Signed-off-by: default avatarMike Travis <travis@sgi.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      41df0d61
  29. 07 May, 2007 1 commit
    • Christoph Lameter's avatar
      Safer nr_node_ids and nr_node_ids determination and initial values · 476f3534
      Christoph Lameter authored
      The nr_cpu_ids value is currently only calculated in smp_init.  However, it
      may be needed before (SLUB needs it on kmem_cache_init!) and other kernel
      components may also want to allocate dynamically sized per cpu array before
      smp_init.  So move the determination of possible cpus into sched_init()
      where we already loop over all possible cpus early in boot.
      
      Also initialize both nr_node_ids and nr_cpu_ids with the highest value they
      could take.  If we have accidental users before these values are determined
      then the current valud of 0 may cause too small per cpu and per node arrays
      to be allocated.  If it is set to the maximum possible then we only waste
      some memory for early boot users.
      Signed-off-by: default avatarChristoph Lameter <clameter@sgi.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      476f3534
  30. 21 Feb, 2007 1 commit
  31. 20 Oct, 2006 1 commit
    • Andrew Morton's avatar
      [PATCH] highest_possible_node_id() linkage fix · 6220ec78
      Andrew Morton authored
      Qooting Adrian:
      
      - net/sunrpc/svc.c uses highest_possible_node_id()
      
      - include/linux/nodemask.h says highest_possible_node_id() is
        out-of-line #if MAX_NUMNODES > 1
      
      - the out-of-line highest_possible_node_id() is in lib/cpumask.c
      
      - lib/Makefile: lib-$(CONFIG_SMP) += cpumask.o
        CONFIG_ARCH_DISCONTIGMEM_ENABLE=y, CONFIG_SMP=n, CONFIG_SUNRPC=y
      
      -> highest_possible_node_id() is used in net/sunrpc/svc.c
         CONFIG_NODES_SHIFT defined and > 0
      
      -> include/linux/numa.h: MAX_NUMNODES > 1
      
      -> compile error
      
      The bug is not present on architectures where ARCH_DISCONTIGMEM_ENABLE
      depends on NUMA (but m32r isn't the only affected architecture).
      
      So move the function into page_alloc.c
      
      Cc: Adrian Bunk <bunk@stusta.de>
      Cc: Paul Jackson <pj@sgi.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      6220ec78
  32. 02 Oct, 2006 1 commit
  33. 25 Mar, 2006 4 commits