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  1. 16 Jul, 2013 1 commit
    • H. Peter Anvin's avatar
      x86, bitops: Change bitops to be native operand size · 9b710506
      H. Peter Anvin authored 
      Change the bitops operation to be naturally "long", i.e. 63 bits on
the 64-bit kernel.  Additional bugs are likely to crop up in the
future.

We already have bugs which machines with > 16 TiB of memory in a
single node, as can happen if memory is interleaved.  The x86 bitop
operations take a signed index, so using an unsigned type is not an
option.

Jim Kukunas measured the effect of this patch on kernel size: it adds
2779 bytes to the allyesconfig kernel.  Some of that probably could be
elided by replacing the inline functions with macros which select the
32-bit type if the index is a 32-bit value, something like:

In that case we could also use "Jr" constraints for the 64-bit
version.

However, this would more than double the amount of code for a
relatively small gain.

Note that we can't use ilog2() for _BITOPS_LONG_SHIFT, as that causes
a recursive header inclusion problem.

The change to constant_test_bit() should both generate better code and
give correct result for negative bit indicies.  As previously written
the compiler had to generate extra code to create the proper wrong
result for negative values.
Signed-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
Cc: Jim Kukunas <james.t.kukunas@intel.com>
Link: http://lkml.kernel.org/n/tip-z61ofiwe90xeyb461o72h8ya@git.kernel.org
      9b710506
  3. 28 Jun, 2013 1 commit
    • Wedson Almeida Filho's avatar
      x86: Use asm-goto to implement mutex fast path on x86-64 · 00e55a79
      Wedson Almeida Filho authored 
      The new implementation allows the compiler to better optimize the code; the
original implementation is still used when the kernel is compiled with older
versions of gcc that don't support asm-goto.

Compiling with gcc 4.7.3, the original mutex_lock() is 60 bytes with the fast
path taking 16 instructions; the new mutex_lock() is 42 bytes, with the fast
path taking 12 instructions.

The original mutex_unlock() is 24 bytes with the fast path taking 7
instructions; the new mutex_unlock() is 25 bytes (because the compiler used
a 2-byte ret) with the fast path taking 4 instructions.

The two versions of the functions are included below for reference.

Old:
ffffffff817742a0 <mutex_lock>:
ffffffff817742a0:       55                      push   %rbp
ffffffff817742a1:       48 89 e5                mov    %rsp,%rbp
ffffffff817742a4:       48 83 ec 10             sub    $0x10,%rsp
ffffffff817742a8:       48 89 5d f0             mov    %rbx,-0x10(%rbp)
ffffffff817742ac:       48 89 fb                mov    %rdi,%rbx
ffffffff817742af:       4c 89 65 f8             mov    %r12,-0x8(%rbp)
ffffffff817742b3:       e8 28 15 00 00          callq  ffffffff817757e0 <_cond_resched>
ffffffff817742b8:       48 89 df                mov    %rbx,%rdi
ffffffff817742bb:       f0 ff 0f                lock decl (%rdi)
ffffffff817742be:       79 05                   jns    ffffffff817742c5 <mutex_lock+0x25>
ffffffff817742c0:       e8 cb 04 00 00          callq  ffffffff81774790 <__mutex_lock_slowpath>
ffffffff817742c5:       65 48 8b 04 25 c0 b7    mov    %gs:0xb7c0,%rax
ffffffff817742cc:       00 00
ffffffff817742ce:       4c 8b 65 f8             mov    -0x8(%rbp),%r12
ffffffff817742d2:       48 89 43 18             mov    %rax,0x18(%rbx)
ffffffff817742d6:       48 8b 5d f0             mov    -0x10(%rbp),%rbx
ffffffff817742da:       c9                      leaveq
ffffffff817742db:       c3                      retq

ffffffff81774250 <mutex_unlock>:
ffffffff81774250:       55                      push   %rbp
ffffffff81774251:       48 c7 47 18 00 00 00    movq   $0x0,0x18(%rdi)
ffffffff81774258:       00
ffffffff81774259:       48 89 e5                mov    %rsp,%rbp
ffffffff8177425c:       f0 ff 07                lock incl (%rdi)
ffffffff8177425f:       7f 05                   jg     ffffffff81774266 <mutex_unlock+0x16>
ffffffff81774261:       e8 ea 04 00 00          callq  ffffffff81774750 <__mutex_unlock_slowpath>
ffffffff81774266:       5d                      pop    %rbp
ffffffff81774267:       c3                      retq

New:
ffffffff81774920 <mutex_lock>:
ffffffff81774920:       55                      push   %rbp
ffffffff81774921:       48 89 e5                mov    %rsp,%rbp
ffffffff81774924:       53                      push   %rbx
ffffffff81774925:       48 89 fb                mov    %rdi,%rbx
ffffffff81774928:       e8 a3 0e 00 00          callq  ffffffff817757d0 <_cond_resched>
ffffffff8177492d:       f0 ff 0b                lock decl (%rbx)
ffffffff81774930:       79 08                   jns    ffffffff8177493a <mutex_lock+0x1a>
ffffffff81774932:       48 89 df                mov    %rbx,%rdi
ffffffff81774935:       e8 16 fe ff ff          callq  ffffffff81774750 <__mutex_lock_slowpath>
ffffffff8177493a:       65 48 8b 04 25 c0 b7    mov    %gs:0xb7c0,%rax
ffffffff81774941:       00 00
ffffffff81774943:       48 89 43 18             mov    %rax,0x18(%rbx)
ffffffff81774947:       5b                      pop    %rbx
ffffffff81774948:       5d                      pop    %rbp
ffffffff81774949:       c3                      retq

ffffffff81774730 <mutex_unlock>:
ffffffff81774730:       48 c7 47 18 00 00 00    movq   $0x0,0x18(%rdi)
ffffffff81774737:       00
ffffffff81774738:       f0 ff 07                lock incl (%rdi)
ffffffff8177473b:       7f 0a                   jg     ffffffff81774747 <mutex_unlock+0x17>
ffffffff8177473d:       55                      push   %rbp
ffffffff8177473e:       48 89 e5                mov    %rsp,%rbp
ffffffff81774741:       e8 aa ff ff ff          callq  ffffffff817746f0 <__mutex_unlock_slowpath>
ffffffff81774746:       5d                      pop    %rbp
ffffffff81774747:       f3 c3                   repz retq
Signed-off-by: default avatarWedson Almeida Filho <wedsonaf@gmail.com>
Link: http://lkml.kernel.org/r/1372420245-60021-1-git-send-email-wedsonaf@gmail.comSigned-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
      00e55a79
  5. 25 Jun, 2013 5 commits
  7. 19 Jun, 2013 1 commit
  9. 31 May, 2013 1 commit
  11. 30 May, 2013 5 commits
  13. 29 May, 2013 3 commits
    • Linus Torvalds's avatar
      Merge tag 'pinctrl-fixes-v3.10-3' of... · 7b55eab8
      Linus Torvalds authored 
      Merge tag 'pinctrl-fixes-v3.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl

Pull pin-control fixes from Linus Walleij:
 - Six patches fixing up the suspend/resume and wakeup handling of the
   Samsung and Exynos drivers.
 - Errorpath fixes for four different drivers.  All on the probe()
   errorpath.
 - Make the debugfs code for pin config take the right mutex.

* tag 'pinctrl-fixes-v3.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl: pinconf: take the right mutex
  pinctrl: sunxi: fix error return code in sunxi_pinctrl_probe()
  pinctrl: exynos: Handle suspend/resume of GPIO EINT registers
  pinctrl: samsung: Allow per-bank SoC-specific private data
  pinctrl: samsung: Add support for SoC-specific suspend/resume callbacks
  pinctrl: Don't override the error code in probe error handling
  ARM: EXYNOS: Fix EINT wake-up mask configuration when pinctrl is used
  pinctrl: exynos: Add support for set_irq_wake of wake-up EINTs
  pinctrl: samsung: fix suspend/resume functionality
      7b55eab8
    • Linus Torvalds's avatar
      Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc · c4763215
      Linus Torvalds authored 
      Pull ARM Exynos fixes from Olof Johansson:
 "Here's a shorter set of fixes for 3.10, all for Samsung Exynos
  platforms.

  It also includes a defconfig update so that exynos_defconfig provides
  a meaningful set of drivers to boot an unmodified kernel on the
  Samsung ARM-based Chromebooks."

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: exynos: defconfig update
  ARM: SAMSUNG: Add names to fimd0 IRQ resources
  ARM: EXYNOS: fix software reset logic for EXYNOS5440 SOC
  ARM: EXYNOS: Fix support of Exynos4210 rev0 SoC
  ARM: dts: Enabling samsung-usb2phy driver for exynos5250
      c4763215
    • Olof Johansson's avatar
      ARM: exynos: defconfig update · da9d0fbf
      Olof Johansson authored 
      This turns on a number of configs that are useful on the Chromebook, but also
good to have on in general:

* USB host and MMC drivers(!)
* I2C GPIO arbitration driver
* CYAPA trackpad driver
* simplefb
* CROS EC and keyboard drivers
* S5M8767 driver
* MAX77686 drivers
* MAX8997 driver
* DEVTMPFS + mount
* DM_CRYPT (as module)
* CRYPTOLOOP
* HIGHMEM
* PRINTK timestamps

This also turns off DEBUG_LL, and switches the hardcoded Samsung lowlevel
uart to uart 3 (which is only used to show the "uncompressing kernel"
message at boot, it seems).
Signed-off-by: default avatarOlof Johansson <olof@lixom.net>
Reviewed-by: default avatarDoug Anderson <dianders@chromium.org>
Tested-by: default avatarTushar Behera <tushar.behera@linaro.org>
Acked-by: default avatarKukjin Kim <kgene.kim@samsung.com>
      da9d0fbf
  15. 28 May, 2013 11 commits
  17. 27 May, 2013 10 commits
  19. 26 May, 2013 2 commits
    • Linus Torvalds's avatar
      Linux 3.10-rc3 · e4aa937e
      Linus Torvalds authored
      e4aa937e
    • Manfred Spraul's avatar
      ipc/sem.c: Fix missing wakeups in do_smart_update_queue() · ab465df9
      Manfred Spraul authored 
      do_smart_update_queue() is called when an operation (semop,
semctl(SETVAL), semctl(SETALL), ...) modified the array.  It must check
which of the sleeping tasks can proceed.

do_smart_update_queue() missed a few wakeups:
 - if a sleeping complex op was completed, then all per-semaphore queues
   must be scanned - not only those that were modified by *sops
 - if a sleeping simple op proceeded, then the global queue must be
   scanned again

And:
 - the test for "|sops == NULL) before scanning the global queue is not
   required: If the global queue is empty, then it doesn't need to be
   scanned - regardless of the reason for calling do_smart_update_queue()

The patch is not optimized, i.e.  even completing a wait-for-zero
operation causes a rescan.  This is done to keep the patch as simple as
possible.
Signed-off-by: default avatarManfred Spraul <manfred@colorfullife.com>
Acked-by: default avatarDavidlohr Bueso <davidlohr.bueso@hp.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      ab465df9
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