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  1. Jan 03, 2017
  2. Jan 02, 2017
  3. Dec 31, 2016
  4. Dec 30, 2016
    • Olof Johansson's avatar
      mm/filemap: fix parameters to test_bit() · 98473f9f
      Olof Johansson authored
      
       mm/filemap.c: In function 'clear_bit_unlock_is_negative_byte':
        mm/filemap.c:933:9: error: too few arguments to function 'test_bit'
          return test_bit(PG_waiters);
               ^~~~~~~~
      
      Fixes: b91e1302 ('mm: optimize PageWaiters bit use for unlock_page()')
      Signed-off-by: default avatarOlof Johansson <olof@lixom.net>
      Brown-paper-bag-by: default avatarLinus Torvalds <dummy@duh.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      98473f9f
    • Linus Torvalds's avatar
      mm: optimize PageWaiters bit use for unlock_page() · b91e1302
      Linus Torvalds authored
      In commit 62906027 ("mm: add PageWaiters indicating tasks are
      waiting for a page bit") Nick Piggin made our page locking no longer
      unconditionally touch the hashed page waitqueue, which not only helps
      performance in general, but is particularly helpful on NUMA machines
      where the hashed wait queues can bounce around a lot.
      
      However, the "clear lock bit atomically and then test the waiters bit"
      sequence turns out to be much more expensive than it needs to be,
      because you get a nasty stall when trying to access the same word that
      just got updated atomically.
      
      On architectures where locking is done with LL/SC, this would be trivial
      to fix with a new primitive that clears one bit and tests another
      atomically, but that ends up not working on x86, where the only atomic
      operations that return the result end up being cmpxchg and xadd.  The
      atomic bit operations return the old value of the same bit we changed,
      not the value of an unrelated bit.
      
      On x86, we coul...
      b91e1302
  5. Dec 28, 2016
  6. Dec 27, 2016
  7. Dec 26, 2016
    • Linus Torvalds's avatar
      Linux 4.10-rc1 · 7ce7d89f
      Linus Torvalds authored
      v4.10-rc1
      7ce7d89f
    • Larry Finger's avatar
      powerpc: Fix build warning on 32-bit PPC · 8ae679c4
      Larry Finger authored
      
      I am getting the following warning when I build kernel 4.9-git on my
      PowerBook G4 with a 32-bit PPC processor:
      
          AS      arch/powerpc/kernel/misc_32.o
        arch/powerpc/kernel/misc_32.S:299:7: warning: "CONFIG_FSL_BOOKE" is not defined [-Wundef]
      
      This problem is evident after commit 989cea5c ("kbuild: prevent
      lib-ksyms.o rebuilds"); however, this change in kbuild only exposes an
      error that has been in the code since 2005 when this source file was
      created.  That was with commit 9994a338 ("powerpc: Introduce
      entry_{32,64}.S, misc_{32,64}.S, systbl.S").
      
      The offending line does not make a lot of sense.  This error does not
      seem to cause any errors in the executable, thus I am not recommending
      that it be applied to any stable versions.
      
      Thanks to Nicholas Piggin for suggesting this solution.
      
      Fixes: 9994a338 ("powerpc: Introduce entry_{32,64}.S, misc_{32,64}.S, systbl.S")
      Signed-off-by: default avatarLarry Finger <Larry.Finger@lwfinger.net>
      Cc: Nicholas Piggin <npiggin@gmail.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: linuxppc-dev@lists.ozlabs.org
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      8ae679c4