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  1. 29 7月, 2008 14 次提交
    • A
      mmu-notifiers: add mm_take_all_locks() operation · 7906d00c
      由 Andrea Arcangeli 提交于 
      mm_take_all_locks holds off reclaim from an entire mm_struct.  This allows
mmu notifiers to register into the mm at any time with the guarantee that
no mmu operation is in progress on the mm.

This operation locks against the VM for all pte/vma/mm related operations
that could ever happen on a certain mm.  This includes vmtruncate,
try_to_unmap, and all page faults.

The caller must take the mmap_sem in write mode before calling
mm_take_all_locks().  The caller isn't allowed to release the mmap_sem
until mm_drop_all_locks() returns.

mmap_sem in write mode is required in order to block all operations that
could modify pagetables and free pages without need of altering the vma
layout (for example populate_range() with nonlinear vmas).  It's also
needed in write mode to avoid new anon_vmas to be associated with existing
vmas.

A single task can't take more than one mm_take_all_locks() in a row or it
would deadlock.

mm_take_all_locks() and mm_drop_all_locks are expensive operations that
may have to take thousand of locks.

mm_take_all_locks() can fail if it's interrupted by signals.

When mmu_notifier_register returns, we must be sure that the driver is
notified if some task is in the middle of a vmtruncate for the 'mm' where
the mmu notifier was registered (mmu_notifier_invalidate_range_start/end
is run around the vmtruncation but mmu_notifier_register can run after
mmu_notifier_invalidate_range_start and before
mmu_notifier_invalidate_range_end).  Same problem for rmap paths.  And
we've to remove page pinning to avoid replicating the tlb_gather logic
inside KVM (and GRU doesn't work well with page pinning regardless of
needing tlb_gather), so without mm_take_all_locks when vmtruncate frees
the page, kvm would have no way to notice that it mapped into sptes a page
that is going into the freelist without a chance of any further
mmu_notifier notification.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NAndrea Arcangeli <andrea@qumranet.com>
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Robin Holt <holt@sgi.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Kanoj Sarcar <kanojsarcar@yahoo.com>
Cc: Roland Dreier <rdreier@cisco.com>
Cc: Steve Wise <swise@opengridcomputing.com>
Cc: Avi Kivity <avi@qumranet.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Anthony Liguori <aliguori@us.ibm.com>
Cc: Chris Wright <chrisw@redhat.com>
Cc: Marcelo Tosatti <marcelo@kvack.org>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Izik Eidus <izike@qumranet.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      7906d00c
    • A
      mmu-notifiers: add list_del_init_rcu() · 6beeac76
      由 Andrea Arcangeli 提交于 
      Introduce list_del_init_rcu() and document it.
Signed-off-by: NAndrea Arcangeli <andrea@qumranet.com>
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Robin Holt <holt@sgi.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Kanoj Sarcar <kanojsarcar@yahoo.com>
Cc: Roland Dreier <rdreier@cisco.com>
Cc: Steve Wise <swise@opengridcomputing.com>
Cc: Avi Kivity <avi@qumranet.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Anthony Liguori <aliguori@us.ibm.com>
Cc: Chris Wright <chrisw@redhat.com>
Cc: Marcelo Tosatti <marcelo@kvack.org>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Izik Eidus <izike@qumranet.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      6beeac76
    • D
      arm: fix HAVE_CLK merge goof · 93686ae8
      由 David Brownell 提交于 
      This fixes a merge goof whereby ARCH_EP93XX got the "select HAVE_CLK" line
which belongs instead with ARCH_AT91.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      93686ae8
    • A
      __ratelimit() cpu flags can't be static · 4d9c377c
      由 Alexey Dobriyan 提交于 
      Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      4d9c377c
    • H
      tmpfs: fix kernel BUG in shmem_delete_inode · 14fcc23f
      由 Hugh Dickins 提交于 
      SuSE's insserve initscript ordering program hits kernel BUG at mm/shmem.c:814
on 2.6.26.  It's using posix_fadvise on directories, and the shmem_readpage
method added in 2.6.23 is letting POSIX_FADV_WILLNEED allocate useless pages
to a tmpfs directory, incrementing i_blocks count but never decrementing it.

Fix this by assigning shmem_aops (pointing to readpage and writepage and
set_page_dirty) only when it's needed, on a regular file or a long symlink.

Many thanks to Kel for outstanding bugreport and steps to reproduce it.
Reported-by: NKel Modderman <kel@otaku42.de>
Tested-by: NKel Modderman <kel@otaku42.de>
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Cc: <stable@kernel.org>		[2.6.25.x, 2.6.26.x]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      14fcc23f
    • H
      exec: include pagemap.h again to fix build · ca5b172b
      由 Hugh Dickins 提交于 
      Fix compilation errors on avr32 and without CONFIG_SWAP, introduced by
ba92a43d ("exec: remove some includes")

  In file included from include/asm/tlb.h:24,
                   from fs/exec.c:55:
  include/asm-generic/tlb.h: In function 'tlb_flush_mmu':
  include/asm-generic/tlb.h:76: error: implicit declaration of function 'release_pages'
  include/asm-generic/tlb.h: In function 'tlb_remove_page':
  include/asm-generic/tlb.h:105: error: implicit declaration of function 'page_cache_release'
  make[1]: *** [fs/exec.o] Error 1

This straightforward part-revert is nobody's favourite patch to address
the underlying tlb.h needs swap.h needs pagemap.h (but sparc won't like
that) mess; but appropriate to fix the build now before any overhaul.
Reported-by: NYoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Reported-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Tested-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      ca5b172b
    • L
      Merge branch 'cpus4096-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip · 63add2f2
      由 Linus Torvalds 提交于 
      * 'cpus4096-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  cpu masks: optimize and clean up cpumask_of_cpu()
  cpumask: export cpumask_of_cpu_map
  cpumask: change cpumask_of_cpu_ptr to use new cpumask_of_cpu
  cpumask: put cpumask_of_cpu_map in the initdata section
  cpumask: make cpumask_of_cpu_map generic
      63add2f2
    • J
      ipwireless: fix compile failure · 3684a601
      由 James Bottomley 提交于 
      There's a brown paper bag compile failure introduced by this patch

commit a0138692
Author: David Sterba <dsterba@suse.cz>
Date:   Mon Jul 28 16:53:32 2008 +0200

    ipwireless: Preallocate received packet buffers with MRU size

Really, it can't ever have been even compile tested.  It looks like the
closing bracket is in the wrong place, so this is the fix.
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      3684a601
    • I
      Merge branch 'linus' into cpus4096 · 9e3ee1c3
      由 Ingo Molnar 提交于 
      Conflicts:

	kernel/stop_machine.c
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      9e3ee1c3
    • L
      cpu masks: optimize and clean up cpumask_of_cpu() · e56b3bc7
      由 Linus Torvalds 提交于 
      Clean up and optimize cpumask_of_cpu(), by sharing all the zero words.

Instead of stupidly generating all possible i=0...NR_CPUS 2^i patterns
creating a huge array of constant bitmasks, realize that the zero words
can be shared.

In other words, on a 64-bit architecture, we only ever need 64 of these
arrays - with a different bit set in one single world (with enough zero
words around it so that we can create any bitmask by just offsetting in
that big array). And then we just put enough zeroes around it that we
can point every single cpumask to be one of those things.

So when we have 4k CPU's, instead of having 4k arrays (of 4k bits each,
with one bit set in each array - 2MB memory total), we have exactly 64
arrays instead, each 8k bits in size (64kB total).

And then we just point cpumask(n) to the right position (which we can
calculate dynamically). Once we have the right arrays, getting
"cpumask(n)" ends up being:

  static inline const cpumask_t *get_cpu_mask(unsigned int cpu)
  {
          const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
          p -= cpu / BITS_PER_LONG;
          return (const cpumask_t *)p;
  }

This brings other advantages and simplifications as well:

 - we are not wasting memory that is just filled with a single bit in
   various different places

 - we don't need all those games to re-create the arrays in some dense
   format, because they're already going to be dense enough.

if we compile a kernel for up to 4k CPU's, "wasting" that 64kB of memory
is a non-issue (especially since by doing this "overlapping" trick we
probably get better cache behaviour anyway).

[ mingo@elte.hu:

  Converted Linus's mails into a commit. See:

     http://lkml.org/lkml/2008/7/27/156
     http://lkml.org/lkml/2008/7/28/320

  Also applied a family filter - which also has the side-effect of leaving
  out the bits where Linus calls me an idio... Oh, never mind ;-)
]
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Mike Travis <travis@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      e56b3bc7
    • I
      Merge branch 'linus' into cpus4096 · 414f746d
      由 Ingo Molnar 提交于
      414f746d
    • L
      Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input · f934fb19
      由 Linus Torvalds 提交于 
      * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: add driver for Atmel integrated touchscreen controller
  Input: ads7846 - optimize order of calculating Rt in ads7846_rx()
  Input: ads7846 - fix sparse endian warnings
  Input: uinput - remove duplicate include
  Input: serio - offload resume to kseriod
  Input: serio - mark serio_register_driver() __must_check
      f934fb19
    • L
      Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm · 3988ba07
      由 Linus Torvalds 提交于 
      * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm:
  dlm: fix uninitialized variable for search_rsb_list callers
  dlm: release socket on error
  dlm: fix basts for granted CW waiting PR/CW
  dlm: check for null in device_write
      3988ba07
    • L
      Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc · d9089c29
      由 Linus Torvalds 提交于 
      * 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (25 commits)
  powerpc: Disable 64K hugetlb support when doing 64K SPU mappings
  powerpc/powermac: Fixup default serial port device for pmac_zilog
  powerpc/powermac: Use sane default baudrate for SCC debugging
  powerpc/mm: Implement _PAGE_SPECIAL & pte_special() for 64-bit
  powerpc: Show processor cache information in sysfs
  powerpc: Make core id information available to userspace
  powerpc: Make core sibling information available to userspace
  powerpc/vio: More fallout from dma_mapping_error API change
  ibmveth: Fix multiple errors with dma_mapping_error conversion
  powerpc/pseries: Fix CMO sysdev attribute API change fallout
  powerpc: Enable tracehook for the architecture
  powerpc: Add TIF_NOTIFY_RESUME support for tracehook
  powerpc: Add asm/syscall.h with the tracehook entry points
  powerpc: Make syscall tracing use tracehook.h helpers
  powerpc: Call tracehook_signal_handler() when setting up signal frames
  powerpc: Update cpu_sibling_maps dynamically
  powerpc: register_cpu_online should be __cpuinit
  powerpc: kill useless SMT code in prom_hold_cpus
  powerpc: Fix 8xx build failure
  powerpc: Fix vio build warnings
  ...
      d9089c29
  3. 28 7月, 2008 26 次提交