[GIT PULL] percpu for v2.6.32

[GIT PULL] percpu for v2.6.32

[Tejun Heo]

Hello, Linus.

Please consider pulling from

  git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu.git for-linus

to receive percpu changes.  Pulling will cause the following conflict
at kernel/sched.c::298.

  <<<<<<< HEAD
  static DEFINE_PER_CPU_SHARED_ALIGNED(struct cfs_rq, init_cfs_rq);
  =======
  static DEFINE_PER_CPU(struct cfs_rq, init_tg_cfs_rq) ____cacheline_aligned_in_smp;
  >>>>>>> 2ca7d674d7ab2220707b2ada0b690c0e7c95e7ac
  #endif /* CONFIG_FAIR_GROUP_SCHED */

Which can be resolved as

  static DEFINE_PER_CPU_SHARED_ALIGNED(struct cfs_rq, init_tg_cfs_rq);

There have been a lot of changes.  Major changes are,

* Percpu allocator now does sparse congruent allocation in vmalloc
  area, which allows archs to allocate the first percpu units for each
  cpu in whatever way they want.  percpu allocator will allocate
  further chunks while maintaining their relative offsets.  This
  allows archs to simply alloc bootmem for each cpu and then feed the
  addresses to the percpu allocator.  So, the first percpu chunk (the
  static percpu variables and a bit of reserved space for dynamic
  ones) can share the usual linear address mapping.

  This makes arch implementations very simple and archs no longer have
  to trade off between allocating in NUMA-friendly way and added TLB
  pressure.  The removal of aliases also allows removing pageattr
  special case handling on x86.

* With embedded allocator extended to handle sparse embedding, lpage
  remapping allocator is no longer necessary and removed.  Internal
  implementation has been made more flexible in the process and arch
  specific code has been made generic.  If we ever need large pages
  for dynamic percpu allocations, it should be pretty easy to
  implement now.

* All arches except for ia64 have been converted to use the new
  allocator.

* This merge will bring the annoying limitation where all percpu
  symbols including the static ones need to be unique.  This was
  necessary to convert alpha and s390 to the new allocator.  The
  problem was that those archs assume static symbols to be addressable
  with reduced addressing range.  The assumption can be met for the
  kernel image but module texts and their percpu data end up very far
  breaking the assumption.  Using __weak attribute for percpu symbols
  forces the compiler to generate GOT based long addressing and thus
  works around the problem but with the said annoying restriction.

  Only alpha and s390 require it but CONFIG_DEBUG_FORCE_WEAK_PER_CPU
  enables the restriction for all so that we can avoid introducing
  duplicate symbols.

  This restriction can be lifted in one of the following two ways.

  1. Teaching gcc that those symbols aren't going to be located near
     text.  Most likely a new variable attribute.

  2. Reserving memory area near builtin text so that module text and
     data can be loaded near builtin text.  Percpu allocator already
     supports reserved area for module percpu variables in the first
     chunk, so half of the problem is already solved.

  #2 is much more likely and probably the right thing to do.  The only
  problem is that alpha and s390 are very difficult to come by.
  Fortunately, the uniqueness restriction is more of annoyance than
  pain.  For the time being, I think it should be okay but if anyone
  is interested in lifting this restriction, I'll be more than happy
  to help.

Thanks.
---
Fenghua Yu (1):
      ia64: Fix setup_per_cpu_areas() compilation error

Jesper Nilsson (1):
      CRIS: Change DEFINE_PER_CPU of current_pgd to be non volatile.

Michal Simek (1):
      microblaze: include EXIT_TEXT to _stext

Tejun Heo (46):
      percpu: use dynamic percpu allocator as the default percpu allocator
      linker script: throw away .discard section
      percpu: cleanup percpu array definitions
      percpu: use DEFINE_PER_CPU_SHARED_ALIGNED()
      percpu: clean up percpu variable definitions
      percpu: implement optional weak percpu definitions
      alpha: kill unnecessary __used attribute in PER_CPU_ATTRIBUTES
      alpha: switch to dynamic percpu allocator
      s390: switch to dynamic percpu allocator
      sparc64: fix build breakage introduced by percpu-convert-most patchset
      percpu: use __weak only in the definition of weak percpu variables
      Merge branch 'master' into for-next
      x86: make pcpu_chunk_addr_search() matching stricter
      percpu: drop @unit_size from embed first chunk allocator
      x86,percpu: generalize 4k first chunk allocator
      percpu: make 4k first chunk allocator map memory
      x86,percpu: generalize lpage first chunk allocator
      percpu: simplify pcpu_setup_first_chunk()
      percpu: reorder a few functions in mm/percpu.c
      percpu: drop pcpu_chunk->page[]
      percpu: allow non-linear / sparse cpu -> unit mapping
      percpu: teach large page allocator about NUMA
      linker script: unify usage of discard definition
      percpu: add dummy pcpu_lpage_remapped() for !CONFIG_SMP
      Merge branch 'percpu-for-linus' into percpu-for-next
      percpu: fix pcpu_reclaim() locking
      percpu: improve boot messages
      percpu: rename 4k first chunk allocator to page
      percpu: build first chunk allocators selectively
      percpu: generalize first chunk allocator selection
      percpu: drop @static_size from first chunk allocators
      percpu: make @dyn_size mandatory for pcpu_setup_first_chunk()
      percpu: add @align to pcpu_fc_alloc_fn_t
      percpu: move pcpu_lpage_build_unit_map() and pcpul_lpage_dump_cfg() upward
      percpu: introduce pcpu_alloc_info and pcpu_group_info
      percpu: add pcpu_unit_offsets[]
      percpu: add chunk->base_addr
      vmalloc: separate out insert_vmalloc_vm()
      vmalloc: implement pcpu_get_vm_areas()
      percpu: use group information to allocate vmap areas sparsely
      percpu: update embedding first chunk allocator to handle sparse units
      x86,percpu: use embedding for 64bit NUMA and page for 32bit NUMA
      percpu: kill lpage first chunk allocator
      sparc64: use embedding percpu first chunk allocator
      powerpc64: convert to dynamic percpu allocator
      Merge branch 'for-next' into for-linus

 Documentation/kernel-parameters.txt    |   11 +-
 Makefile                               |    2 +-
 arch/alpha/include/asm/percpu.h        |  100 +--
 arch/alpha/include/asm/tlbflush.h      |    1 +
 arch/alpha/kernel/vmlinux.lds.S        |    9 +-
 arch/arm/kernel/vmlinux.lds.S          |    1 +
 arch/avr32/kernel/vmlinux.lds.S        |    9 +-
 arch/blackfin/kernel/vmlinux.lds.S     |    5 +-
 arch/blackfin/mm/sram-alloc.c          |    6 +-
 arch/cris/include/asm/mmu_context.h    |    3 +-
 arch/cris/kernel/vmlinux.lds.S         |    9 +-
 arch/cris/mm/fault.c                   |    2 +-
 arch/frv/kernel/vmlinux.lds.S          |    2 +
 arch/h8300/kernel/vmlinux.lds.S        |    5 +-
 arch/ia64/Kconfig                      |    3 +
 arch/ia64/kernel/setup.c               |    6 +
 arch/ia64/kernel/smp.c                 |    3 +-
 arch/ia64/kernel/vmlinux.lds.S         |   16 +-
 arch/ia64/sn/kernel/setup.c            |    2 +-
 arch/m32r/kernel/vmlinux.lds.S         |   10 +-
 arch/m68k/kernel/vmlinux-std.lds       |   10 +-
 arch/m68k/kernel/vmlinux-sun3.lds      |    9 +-
 arch/m68knommu/kernel/vmlinux.lds.S    |    7 +-
 arch/microblaze/kernel/vmlinux.lds.S   |    6 +-
 arch/mips/kernel/vmlinux.lds.S         |   21 +-
 arch/mn10300/kernel/vmlinux.lds.S      |    8 +-
 arch/parisc/kernel/vmlinux.lds.S       |    8 +-
 arch/powerpc/Kconfig                   |    3 +
 arch/powerpc/kernel/setup_64.c         |   61 +-
 arch/powerpc/kernel/vmlinux.lds.S      |    9 +-
 arch/powerpc/mm/stab.c                 |    2 +-
 arch/powerpc/platforms/ps3/smp.c       |    2 +-
 arch/s390/include/asm/percpu.h         |   32 +-
 arch/s390/kernel/vmlinux.lds.S         |    9 +-
 arch/sh/kernel/vmlinux.lds.S           |   10 +-
 arch/sparc/Kconfig                     |    2 +-
 arch/sparc/kernel/smp_64.c             |  132 +---
 arch/sparc/kernel/vmlinux.lds.S        |    8 +-
 arch/um/include/asm/common.lds.S       |    5 -
 arch/um/kernel/dyn.lds.S               |    2 +
 arch/um/kernel/uml.lds.S               |    2 +
 arch/x86/Kconfig                       |    5 +-
 arch/x86/include/asm/percpu.h          |    9 -
 arch/x86/kernel/cpu/cpu_debug.c        |    4 +-
 arch/x86/kernel/cpu/mcheck/mce.c       |    8 +-
 arch/x86/kernel/cpu/mcheck/mce_amd.c   |    2 +-
 arch/x86/kernel/cpu/perf_counter.c     |   14 +-
 arch/x86/kernel/setup_percpu.c         |  364 +-------
 arch/x86/kernel/vmlinux.lds.S          |   11 +-
 arch/x86/mm/pageattr.c                 |   21 +-
 arch/xtensa/kernel/vmlinux.lds.S       |   13 +-
 block/as-iosched.c                     |   10 +-
 block/cfq-iosched.c                    |   10 +-
 drivers/cpufreq/cpufreq_conservative.c |   12 +-
 drivers/cpufreq/cpufreq_ondemand.c     |   15 +-
 drivers/xen/events.c                   |   13 +-
 include/asm-generic/vmlinux.lds.h      |   24 +-
 include/linux/percpu-defs.h            |   66 ++-
 include/linux/percpu.h                 |   88 ++-
 include/linux/vmalloc.h                |    6 +
 init/main.c                            |   24 -
 kernel/module.c                        |    6 +-
 kernel/perf_counter.c                  |    6 +-
 kernel/sched.c                         |    4 +-
 kernel/trace/trace_events.c            |    6 +-
 lib/Kconfig.debug                      |   15 +
 mm/Makefile                            |    2 +-
 mm/allocpercpu.c                       |   28 +
 mm/kmemleak-test.c                     |    6 +-
 mm/page-writeback.c                    |    5 +-
 mm/percpu.c                            | 1420 ++++++++++++++++++++++++--------
 mm/quicklist.c                         |    2 +-
 mm/slub.c                              |    4 +-
 mm/vmalloc.c                           |  338 +++++++-
 net/ipv4/syncookies.c                  |    5 +-
 net/ipv6/syncookies.c                  |    5 +-
 net/rds/ib_stats.c                     |    2 +-
 net/rds/iw_stats.c                     |    2 +-
 net/rds/page.c                         |    2 +-
 scripts/module-common.lds              |    8 +
 80 files changed, 1910 insertions(+), 1228 deletions(-)
 create mode 100644 scripts/module-common.lds

--
tejun

Re: [GIT PULL] percpu for v2.6.32

[Christoph Lameter]

On Tue, 15 Sep 2009, Tejun Heo wrote:

> * All arches except for ia64 have been converted to use the new
>   allocator.

Any plans for this? The percpu operations patchset
requires the new allocator to work on all platforms and I am wondering
when I should repost the set.

Re: [GIT PULL] percpu for v2.6.32

[Tejun Heo]

Christoph Lameter wrote:
> On Tue, 15 Sep 2009, Tejun Heo wrote:
> 
>> * All arches except for ia64 have been converted to use the new
>>   allocator.
> 
> Any plans for this? The percpu operations patchset
> requires the new allocator to work on all platforms and I am wondering
> when I should repost the set.

I've been trying to get a cheap second hand itanium machine but itanic
really seems to have sunk pretty well.  It's almost impossible to find
one here.  I guess I'll have to bite the bullet and do it remotely.
There gotta be one with serial console and power control hooked up
somewhere in the company lab.  I'll try to locate one.

Thanks.

-- 
tejun

Re: [GIT PULL] percpu for v2.6.32

[Christoph Lameter]

On Wed, 16 Sep 2009, Tejun Heo wrote:

> Christoph Lameter wrote:
> > On Tue, 15 Sep 2009, Tejun Heo wrote:
> >
> >> * All arches except for ia64 have been converted to use the new
> >>   allocator.
> >
> > Any plans for this? The percpu operations patchset
> > requires the new allocator to work on all platforms and I am wondering
> > when I should repost the set.
>
> I've been trying to get a cheap second hand itanium machine but itanic
> really seems to have sunk pretty well.  It's almost impossible to find
> one here.  I guess I'll have to bite the bullet and do it remotely.
> There gotta be one with serial console and power control hooked up
> somewhere in the company lab.  I'll try to locate one.

Maybe Mike knows of some way to get access to one?

Re: [GIT PULL] percpu for v2.6.32

[Mike Travis]

Christoph Lameter wrote:
> On Wed, 16 Sep 2009, Tejun Heo wrote:
> 
>> Christoph Lameter wrote:
>>> On Tue, 15 Sep 2009, Tejun Heo wrote:
>>>
>>>> * All arches except for ia64 have been converted to use the new
>>>>   allocator.
>>> Any plans for this? The percpu operations patchset
>>> requires the new allocator to work on all platforms and I am wondering
>>> when I should repost the set.
>> I've been trying to get a cheap second hand itanium machine but itanic
>> really seems to have sunk pretty well.  It's almost impossible to find
>> one here.  I guess I'll have to bite the bullet and do it remotely.
>> There gotta be one with serial console and power control hooked up
>> somewhere in the company lab.  I'll try to locate one.
> 
> Maybe Mike knows of some way to get access to one?

We certainly have some in our labs but I'm not sure of one that's
externally accessible.  If there's a pre-defined test you'd like to
run, you can send me the details.  Otherwise, I'll check around and
see if there's a system available remotely.

Cheers,
Mike

Re: [GIT PULL] percpu for v2.6.32

[Tejun Heo]

Hello,

Mike Travis wrote:
> We certainly have some in our labs but I'm not sure of one that's
> externally accessible.  If there's a pre-defined test you'd like to
> run, you can send me the details.  Otherwise, I'll check around and
> see if there's a system available remotely.

The proposed broken patch is in the following thread.  It works on ski
emulator but ski doesn't support SMP, so...

 http://thread.gmane.org/gmane.linux.kernel.cross-arch/4132

The patch shouldn't be too broken.  It probably needs slight tweaks
here and there.  Just testing and providing logs would be helpful
enough.

Thanks.

-- 
tejun

Re: [GIT PULL] percpu for v2.6.32

[Robin Holt]

Mike, if you can not find one, let me know.  I would try the benchmarkers.
IIRC, they may have those already ready to go.

Tejun, I have an SGI Prism at home that is normally powered off.
I could power that up, get you set up to access it, and let you lose.
There are basic commands for using the L2 to power on and off and to
reset.  I think it is currently set up with some bad dimms so I would
need to remove those before this evolution.

I wouldn't mind helping with the patches, but I have no time right
now.

Thanks,
Robin


On Wed, Sep 16, 2009 at 10:28:03AM +0900, Tejun Heo wrote:
> Hello,
> 
> Mike Travis wrote:
> > We certainly have some in our labs but I'm not sure of one that's
> > externally accessible.  If there's a pre-defined test you'd like to
> > run, you can send me the details.  Otherwise, I'll check around and
> > see if there's a system available remotely.
> 
> The proposed broken patch is in the following thread.  It works on ski
> emulator but ski doesn't support SMP, so...
> 
>  http://thread.gmane.org/gmane.linux.kernel.cross-arch/4132
> 
> The patch shouldn't be too broken.  It probably needs slight tweaks
> here and there.  Just testing and providing logs would be helpful
> enough.
> 
> Thanks.
> 
> -- 
> tejun
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/

Re: [GIT PULL] percpu for v2.6.32

[Robin Holt]

Of course, you could ignore this from 7 months ago if you like.  I had
resorted my lkml mailbox and then got myself confused.  The offer does
stand if you still need access.

Thanks,
Robin

On Tue, Apr 20, 2010 at 02:56:43AM -0500, Robin Holt wrote:
> Mike, if you can not find one, let me know.  I would try the benchmarkers.
> IIRC, they may have those already ready to go.
> 
> Tejun, I have an SGI Prism at home that is normally powered off.
> I could power that up, get you set up to access it, and let you lose.
> There are basic commands for using the L2 to power on and off and to
> reset.  I think it is currently set up with some bad dimms so I would
> need to remove those before this evolution.
> 
> I wouldn't mind helping with the patches, but I have no time right
> now.
> 
> Thanks,
> Robin
> 
> 
> On Wed, Sep 16, 2009 at 10:28:03AM +0900, Tejun Heo wrote:
> > Hello,
> > 
> > Mike Travis wrote:
> > > We certainly have some in our labs but I'm not sure of one that's
> > > externally accessible.  If there's a pre-defined test you'd like to
> > > run, you can send me the details.  Otherwise, I'll check around and
> > > see if there's a system available remotely.
> > 
> > The proposed broken patch is in the following thread.  It works on ski
> > emulator but ski doesn't support SMP, so...
> > 
> >  http://thread.gmane.org/gmane.linux.kernel.cross-arch/4132
> > 
> > The patch shouldn't be too broken.  It probably needs slight tweaks
> > here and there.  Just testing and providing logs would be helpful
> > enough.
> > 
> > Thanks.
> > 
> > -- 
> > tejun
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html
> > Please read the FAQ at  http://www.tux.org/lkml/
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/

Re: [GIT PULL] percpu for v2.6.32

[Tejun Heo]

Hello,

On 04/20/2010 05:05 PM, Robin Holt wrote:
> Of course, you could ignore this from 7 months ago if you like.  I had
> resorted my lkml mailbox and then got myself confused.  The offer does
> stand if you still need access.

Heh, yeah, I found a couple itanium machines in suse machine room.
Thanks anyway.

-- 
tejun