Граф коммитов

2504 Коммитов

Автор SHA1 Сообщение Дата
Richard Laager ee8a99bdb4 lib/lz4: correct the LZ4 license
The LZ4 code is listed as using the "BSD 2-Clause License".

Signed-off-by: Richard Laager <rlaager@wiktel.com>
Acked-by: Kyungsik Lee <kyungsik.lee@lge.com>
Cc: Chanho Min <chanho.min@lge.com>
Cc: Richard Yao <ryao@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ The 2-clause BSD can be just converted into GPL, but that's rude and
  pointless, so don't do it   - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-08-23 09:51:22 -07:00
Mike Snitzer eb18cba78c math64: New separate div64_u64_rem helper
Commit f792685006 ("math64: New
div64_u64_rem helper") implemented div64_u64 in terms of div64_u64_rem.
But div64_u64_rem was removed because it slowed down div64_u64 (and
there were no other users of div64_u64_rem).

Device Mapper's I/O statistics support has a need for div64_u64_rem;
reintroduce this helper as a separate method that doesn't slow down
div64_u64, especially on 32-bit systems.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2013-08-23 09:02:14 -04:00
Paul E. McKenney b778ae2536 debugobjects: Make debug_object_activate() return status
In order to better respond to things like duplicate invocations
of call_rcu(), RCU needs to see the status of a call to
debug_object_activate().  This would allow RCU to leak the callback in
order to avoid adding freelist-reuse mischief to the duplicate invoations.
This commit therefore makes debug_object_activate() return status,
zero for success and -EINVAL for failure.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Davidlohr Bueso <davidlohr.bueso@hp.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2013-08-18 17:39:55 -07:00
Tang Chen 598bae70c2 earlycpio.c: Fix the confusing comment of find_cpio_data().
The comments of find_cpio_data() says:

  * @offset: When a matching file is found, this is the offset to the
  *          beginning of the cpio. ......

But according to the code,

  dptr = PTR_ALIGN(p + ch[C_NAMESIZE], 4);
  nptr = PTR_ALIGN(dptr + ch[C_FILESIZE], 4);
  ....
  *offset = (long)nptr - (long)data;	/* data is the cpio file */

@offset is the offset of the next file, not the matching file itself.
This is confused and may cause unnecessary waste of time to debug.
So fix it.

As Tejun Heo suggested, rename @offset to @nextoff which is more clear
to users. And also adjust the new comments.

Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Reviewed-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Reviewed-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-14 23:24:01 +02:00
EunBong Song 4d86ec7a8a swiotlb: replace dma_length with sg_dma_len() macro
This patch replace dma_length in "lib/swiotlb.c" to sg_dma_len() macro,
because the build error can occur if CONFIG_NEED_SG_DMA_LENGTH is not
set, and CONFIG_SWIOTLB is set.

Singed-off-by: EunBong Song <eunb.song@samsung.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-08-09 11:28:42 -04:00
Andi Kleen b6c035d04e x86, asmlinkage: Make dump_stack visible
dump_stack is used from assembler code, so make it visible.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1375740170-7446-15-git-send-email-andi@firstfloor.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-08-06 14:21:01 -07:00
Greg Kroah-Hartman b78b6b3a9a Merge 3.11-rc3 into driver-core-next
We want these fixes in this branch.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-29 12:30:13 -07:00
Russell King c817a67ecb kobject: delayed kobject release: help find buggy drivers
Implement debugging for kobject release functions.  kobjects are
reference counted, so the drop of the last reference to them is not
predictable. However, the common case is for the last reference to be
the kobject's removal from a subsystem, which results in the release
function being immediately called.

This can hide subtle bugs, which can occur when another thread holds a
reference to the kobject at the same time that a kobject is removed.
This results in the release method being delayed.

In order to make these kinds of problems more visible, the following
patch implements a delayed release; this has the effect that the
release function will be out of order with respect to the removal of
the kobject in the same manner that it would be if a reference was
being held.

This provides us with an easy way to allow driver writers to debug
their drivers and fix otherwise hidden problems.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-25 15:39:04 -07:00
Linus Torvalds b48a97be8e Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fixes from Herbert Xu:
 "This push fixes a memory corruption issue in caam, as well as
  reverting the new optimised crct10dif implementation as it breaks boot
  on initrd systems.

  Hopefully crct10dif will be reinstated once the supporting code is
  added so that it doesn't break boot"

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  Revert "crypto: crct10dif - Wrap crc_t10dif function all to use crypto transform framework"
  crypto: caam - Fixed the memory out of bound overwrite issue
2013-07-24 11:05:18 -07:00
Herbert Xu e70308ec0e Revert "crypto: crct10dif - Wrap crc_t10dif function all to use crypto transform framework"
This reverts commits
    67822649d7
    39761214ee
    0b95a7f857
    31d939625a
    2d31e518a4

Unfortunately this change broke boot on some systems that used an
initrd which does not include the newly created crct10dif modules.
As these modules are required by sd_mod under certain configurations
this is a serious problem.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-07-24 17:04:16 +10:00
Russell King b4f656eea6 Pull branch 'for-rmk' of git://git.linaro.org/people/ardbiesheuvel/linux-arm into devel-stable
Comments from Ard Biesheuvel:

I have included two use cases that I have been using, XOR and RAID-6
checksumming. The former gets a 60% performance boost on the NEON, the
latter over 400%.

ARM: add support for kernel mode NEON

Adds kernel_neon_begin/end (renamed from kernel_vfp_begin/end in the
previous version to de-emphasize the VFP part as VFP code that needs
software assistance is not supported currently.)

Introduces <asm/neon.h> and the Kconfig symbol KERNEL_MODE_NEON. This
has been aligned with Catalin for arm64, so any NEON code that does
not use assembly but intrinsics or the GCC vectorizer (such as my
examples) can potentially be shared between arm and arm64 archs.

ARM: move VFP init to an earlier boot stage

This is needed so the NEON is enabled when the XOR and RAID-6 algo
boot time benchmarks are run.

ARM: be strict about FP exceptions in kernel mode

This adds a check to vfp_support_entry() to flag unsupported uses of
the NEON/VFP in kernel mode. FP exceptions (bounces) are flagged as
a bug, this is because of their potentially intermittent nature.
Exceptions caused by the fact that kernel_neon_begin has not been
called are just routed through the undef handler.

ARM: crypto: add NEON accelerated XOR implementation

This is the xor_blocks() implementation built with -ftree-vectorize,
60% faster than optimized ARM code. It calls in_interrupt() to check
whether the NEON flavor can be used: this should really not be
necessary, but due to xor_blocks'squite generic nature, there is no
telling how exactly people may be using it in the real world.

lib/raid6: add ARM-NEON accelerated syndrome calculation

This is a port of the RAID-6 checksumming code in altivec.uc ported
to use NEON intrinsics. It is about 4x faster than the sequential
code.
2013-07-22 17:46:40 +01:00
Richard Henderson a5c6eae4d6 alpha: Modernize lib/mpi/longlong.h
Remove the compile warning for __udiv_qrnnd not having a prototype.
Use the __builtin_alpha_umulh introduced in gcc 4.0.

Reviewed-and-Tested-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2013-07-19 13:54:23 -07:00
Paul Gortmaker 0db0628d90 kernel: delete __cpuinit usage from all core kernel files
The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

This removes all the uses of the __cpuinit macros from C files in
the core kernel directories (kernel, init, lib, mm, and include)
that don't really have a specific maintainer.

[1] https://lkml.org/lkml/2013/5/20/589

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-07-14 19:36:59 -04:00
Linus Torvalds 41d9884c44 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more vfs stuff from Al Viro:
 "O_TMPFILE ABI changes, Oleg's fput() series, misc cleanups, including
  making simple_lookup() usable for filesystems with non-NULL s_d_op,
  which allows us to get rid of quite a bit of ugliness"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  sunrpc: now we can just set ->s_d_op
  cgroup: we can use simple_lookup() now
  efivarfs: we can use simple_lookup() now
  make simple_lookup() usable for filesystems that set ->s_d_op
  configfs: don't open-code d_alloc_name()
  __rpc_lookup_create_exclusive: pass string instead of qstr
  rpc_create_*_dir: don't bother with qstr
  llist: llist_add() can use llist_add_batch()
  llist: fix/simplify llist_add() and llist_add_batch()
  fput: turn "list_head delayed_fput_list" into llist_head
  fs/file_table.c:fput(): add comment
  Safer ABI for O_TMPFILE
2013-07-14 11:42:26 -07:00
Linus Torvalds 4fa109b130 Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core locking updates from Thomas Gleixner:
 "Header cleanup as requested by Linus"

(This is the "don't include support for ww_mutex in a header file that
everybody wants, when almost nobody wants the ww part" change)

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  mutex: Move ww_mutex definitions to ww_mutex.h
2013-07-13 15:35:12 -07:00
Linus Torvalds d144746478 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS updates from Ralf Baechle:
 "MIPS updates:

   - All the things that didn't make 3.10.
   - Removes the Windriver PPMC platform.  Nobody will miss it.
   - Remove a workaround from kernel/irq/irqdomain.c which was there
     exclusivly for MIPS.  Patch by Grant Likely.
   - More small improvments for the SEAD 3 platform
   - Improvments on the BMIPS / SMP support for the BCM63xx series.
   - Various cleanups of dead leftovers.
   - Platform support for the Cavium Octeon-based EdgeRouter Lite.

  Two large KVM patchsets didn't make it for this pull request because
  their respective authors are vacationing"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (124 commits)
  MIPS: Kconfig: Add missing MODULES dependency to VPE_LOADER
  MIPS: BCM63xx: CLK: Add dummy clk_{set,round}_rate() functions
  MIPS: SEAD3: Disable L2 cache on SEAD-3.
  MIPS: BCM63xx: Enable second core SMP on BCM6328 if available
  MIPS: BCM63xx: Add SMP support to prom.c
  MIPS: define write{b,w,l,q}_relaxed
  MIPS: Expose missing pci_io{map,unmap} declarations
  MIPS: Malta: Update GCMP detection.
  Revert "MIPS: make CAC_ADDR and UNCAC_ADDR account for PHYS_OFFSET"
  MIPS: APSP: Remove <asm/kspd.h>
  SSB: Kconfig: Amend SSB_EMBEDDED dependencies
  MIPS: microMIPS: Fix improper definition of ISA exception bit.
  MIPS: Don't try to decode microMIPS branch instructions where they cannot exist.
  MIPS: Declare emulate_load_store_microMIPS as a static function.
  MIPS: Fix typos and cleanup comment
  MIPS: Cleanup indentation and whitespace
  MIPS: BMIPS: support booting from physical CPU other than 0
  MIPS: Only set cpu_has_mmips if SYS_SUPPORTS_MICROMIPS
  MIPS: GIC: Fix gic_set_affinity infinite loop
  MIPS: Don't save/restore OCTEON wide multiplier state on syscalls.
  ...
2013-07-13 14:52:21 -07:00
Oleg Nesterov fb4214db50 llist: fix/simplify llist_add() and llist_add_batch()
1. This is mostly theoretical, but llist_add*() need ACCESS_ONCE().

   Otherwise it is not guaranteed that the first cmpxchg() uses the
   same value for old_entry and new_last->next.

2. These helpers cache the result of cmpxchg() and read the initial
   value of head->first before the main loop. I do not think this
   makes sense. In the likely case cmpxchg() succeeds, otherwise
   it doesn't hurt to reload head->first.

   I think it would be better to simplify the code and simply read
   ->first before cmpxchg().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrey Vagin <avagin@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-07-13 13:29:24 +04:00
Maarten Lankhorst 1b375dc307 mutex: Move ww_mutex definitions to ww_mutex.h
Move the definitions for wound/wait mutexes out to a separate
header, ww_mutex.h. This reduces clutter in mutex.h, and
increases readability.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Dave Airlie <airlied@gmail.com>
Link: http://lkml.kernel.org/r/51D675DC.3000907@canonical.com
[ Tidied up the code a bit. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-07-12 12:07:46 +02:00
Linus Torvalds 496322bc91 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "This is a re-do of the net-next pull request for the current merge
  window.  The only difference from the one I made the other day is that
  this has Eliezer's interface renames and the timeout handling changes
  made based upon your feedback, as well as a few bug fixes that have
  trickeled in.

  Highlights:

   1) Low latency device polling, eliminating the cost of interrupt
      handling and context switches.  Allows direct polling of a network
      device from socket operations, such as recvmsg() and poll().

      Currently ixgbe, mlx4, and bnx2x support this feature.

      Full high level description, performance numbers, and design in
      commit 0a4db187a9 ("Merge branch 'll_poll'")

      From Eliezer Tamir.

   2) With the routing cache removed, ip_check_mc_rcu() gets exercised
      more than ever before in the case where we have lots of multicast
      addresses.  Use a hash table instead of a simple linked list, from
      Eric Dumazet.

   3) Add driver for Atheros CQA98xx 802.11ac wireless devices, from
      Bartosz Markowski, Janusz Dziedzic, Kalle Valo, Marek Kwaczynski,
      Marek Puzyniak, Michal Kazior, and Sujith Manoharan.

   4) Support reporting the TUN device persist flag to userspace, from
      Pavel Emelyanov.

   5) Allow controlling network device VF link state using netlink, from
      Rony Efraim.

   6) Support GRE tunneling in openvswitch, from Pravin B Shelar.

   7) Adjust SOCK_MIN_RCVBUF and SOCK_MIN_SNDBUF for modern times, from
      Daniel Borkmann and Eric Dumazet.

   8) Allow controlling of TCP quickack behavior on a per-route basis,
      from Cong Wang.

   9) Several bug fixes and improvements to vxlan from Stephen
      Hemminger, Pravin B Shelar, and Mike Rapoport.  In particular,
      support receiving on multiple UDP ports.

  10) Major cleanups, particular in the area of debugging and cookie
      lifetime handline, to the SCTP protocol code.  From Daniel
      Borkmann.

  11) Allow packets to cross network namespaces when traversing tunnel
      devices.  From Nicolas Dichtel.

  12) Allow monitoring netlink traffic via AF_PACKET sockets, in a
      manner akin to how we monitor real network traffic via ptype_all.
      From Daniel Borkmann.

  13) Several bug fixes and improvements for the new alx device driver,
      from Johannes Berg.

  14) Fix scalability issues in the netem packet scheduler's time queue,
      by using an rbtree.  From Eric Dumazet.

  15) Several bug fixes in TCP loss recovery handling, from Yuchung
      Cheng.

  16) Add support for GSO segmentation of MPLS packets, from Simon
      Horman.

  17) Make network notifiers have a real data type for the opaque
      pointer that's passed into them.  Use this to properly handle
      network device flag changes in arp_netdev_event().  From Jiri
      Pirko and Timo Teräs.

  18) Convert several drivers over to module_pci_driver(), from Peter
      Huewe.

  19) tcp_fixup_rcvbuf() can loop 500 times over loopback, just use a
      O(1) calculation instead.  From Eric Dumazet.

  20) Support setting of explicit tunnel peer addresses in ipv6, just
      like ipv4.  From Nicolas Dichtel.

  21) Protect x86 BPF JIT against spraying attacks, from Eric Dumazet.

  22) Prevent a single high rate flow from overruning an individual cpu
      during RX packet processing via selective flow shedding.  From
      Willem de Bruijn.

  23) Don't use spinlocks in TCP md5 signing fast paths, from Eric
      Dumazet.

  24) Don't just drop GSO packets which are above the TBF scheduler's
      burst limit, chop them up so they are in-bounds instead.  Also
      from Eric Dumazet.

  25) VLAN offloads are missed when configured on top of a bridge, fix
      from Vlad Yasevich.

  26) Support IPV6 in ping sockets.  From Lorenzo Colitti.

  27) Receive flow steering targets should be updated at poll() time
      too, from David Majnemer.

  28) Fix several corner case regressions in PMTU/redirect handling due
      to the routing cache removal, from Timo Teräs.

  29) We have to be mindful of ipv4 mapped ipv6 sockets in
      upd_v6_push_pending_frames().  From Hannes Frederic Sowa.

  30) Fix L2TP sequence number handling bugs, from James Chapman."

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1214 commits)
  drivers/net: caif: fix wrong rtnl_is_locked() usage
  drivers/net: enic: release rtnl_lock on error-path
  vhost-net: fix use-after-free in vhost_net_flush
  net: mv643xx_eth: do not use port number as platform device id
  net: sctp: confirm route during forward progress
  virtio_net: fix race in RX VQ processing
  virtio: support unlocked queue poll
  net/cadence/macb: fix bug/typo in extracting gem_irq_read_clear bit
  Documentation: Fix references to defunct linux-net@vger.kernel.org
  net/fs: change busy poll time accounting
  net: rename low latency sockets functions to busy poll
  bridge: fix some kernel warning in multicast timer
  sfc: Fix memory leak when discarding scattered packets
  sit: fix tunnel update via netlink
  dt:net:stmmac: Add dt specific phy reset callback support.
  dt:net:stmmac: Add support to dwmac version 3.610 and 3.710
  dt:net:stmmac: Allocate platform data only if its NULL.
  net:stmmac: fix memleak in the open method
  ipv6: rt6_check_neigh should successfully verify neigh if no NUD information are available
  net: ipv6: fix wrong ping_v6_sendmsg return value
  ...
2013-07-09 18:24:39 -07:00
Dan Carpenter 27daabd9b6 lib/scatterlist: error handling in __sg_alloc_table()
I was reviewing code which I suspected might allocate a zero size SG
table.  That will cause memory corruption.  Also we can't return before
doing the memset or we could end up using uninitialized memory in the
cleanup path.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:31 -07:00
Akinobu Mita df642cea25 lib/scatterlist: introduce sg_pcopy_from_buffer() and sg_pcopy_to_buffer()
The only difference between sg_pcopy_{from,to}_buffer() and
sg_copy_{from,to}_buffer() is an additional argument that specifies the
number of bytes to skip the SG list before copying.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Horia Geanta <horia.geanta@freescale.com>
Cc: Imre Deak <imre.deak@intel.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:30 -07:00
Akinobu Mita 1105200480 lib/scatterlist: factor out sg_miter_get_next_page() from sg_miter_next()
This patchset introduces sg_pcopy_from_buffer() and sg_pcopy_to_buffer(),
which copy data between a linear buffer and an SG list.

The only difference between sg_pcopy_{from,to}_buffer() and
sg_copy_{from,to}_buffer() is an additional argument that specifies the
number of bytes to skip the SG list before copying.

The main reason for introducing these functions is to fix a problem in
scsi_debug module.  And there is a local function in crypto/talitos
module, which can be replaced by sg_pcopy_to_buffer().

This patch:

sg_miter_get_next_page() is used to proceed page iterator to the next page
if necessary, and will be used to implement the variants of
sg_copy_{from,to}_buffer() later.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Horia Geanta <horia.geanta@freescale.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:30 -07:00
Chanho Min c72ac7a1a9 lib: add lz4 compressor module
This patchset is for supporting LZ4 compression and the crypto API using
it.

As shown below, the size of data is a little bit bigger but compressing
speed is faster under the enabled unaligned memory access.  We can use
lz4 de/compression through crypto API as well.  Also, It will be useful
for another potential user of lz4 compression.

lz4 Compression Benchmark:
Compiler: ARM gcc 4.6.4
ARMv7, 1 GHz based board
   Kernel: linux 3.4
   Uncompressed data Size: 101 MB
         Compressed Size  compression Speed
   LZO   72.1MB		  32.1MB/s, 33.0MB/s(UA)
   LZ4   75.1MB		  30.4MB/s, 35.9MB/s(UA)
   LZ4HC 59.8MB		   2.4MB/s,  2.5MB/s(UA)
- UA: Unaligned memory Access support
- Latest patch set for LZO applied

This patch:

Add support for LZ4 compression in the Linux Kernel.  LZ4 Compression APIs
for kernel are based on LZ4 implementation by Yann Collet and were changed
for kernel coding style.

LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html
LZ4 source repository : http://code.google.com/p/lz4/
svn revision : r90

Two APIs are added:

lz4_compress() support basic lz4 compression whereas lz4hc_compress()
support high compression or CPU performance get lower but compression
ratio get higher.  Also, we require the pre-allocated working memory with
the defined size and destination buffer must be allocated with the size of
lz4_compressbound.

[akpm@linux-foundation.org: make lz4_compresshcctx() static]
Signed-off-by: Chanho Min <chanho.min@lge.com>
Cc: "Darrick J. Wong" <djwong@us.ibm.com>
Cc: Bob Pearson <rpearson@systemfabricworks.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Herbert Xu <herbert@gondor.hengli.com.au>
Cc: Yann Collet <yann.collet.73@gmail.com>
Cc: Kyungsik Lee <kyungsik.lee@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:30 -07:00
Kyungsik Lee e76e1fdfa8 lib: add support for LZ4-compressed kernel
Add support for extracting LZ4-compressed kernel images, as well as
LZ4-compressed ramdisk images in the kernel boot process.

Signed-off-by: Kyungsik Lee <kyungsik.lee@lge.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Florian Fainelli <florian@openwrt.org>
Cc: Yann Collet <yann.collet.73@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:30 -07:00
Kyungsik Lee cffb78b0e0 decompressor: add LZ4 decompressor module
Add support for LZ4 decompression in the Linux Kernel.  LZ4 Decompression
APIs for kernel are based on LZ4 implementation by Yann Collet.

Benchmark Results(PATCH v3)
Compiler: Linaro ARM gcc 4.6.2

1. ARMv7, 1.5GHz based board
   Kernel: linux 3.4
   Uncompressed Kernel Size: 14MB
        Compressed Size  Decompression Speed
   LZO  6.7MB            20.1MB/s, 25.2MB/s(UA)
   LZ4  7.3MB            29.1MB/s, 45.6MB/s(UA)

2. ARMv7, 1.7GHz based board
   Kernel: linux 3.7
   Uncompressed Kernel Size: 14MB
        Compressed Size  Decompression Speed
   LZO  6.0MB            34.1MB/s, 52.2MB/s(UA)
   LZ4  6.5MB            86.7MB/s
- UA: Unaligned memory Access support
- Latest patch set for LZO applied

This patch set is for adding support for LZ4-compressed Kernel.  LZ4 is a
very fast lossless compression algorithm and it also features an extremely
fast decoder [1].

But we have five of decompressors already and one question which does
arise, however, is that of where do we stop adding new ones?  This issue
had been discussed and came to the conclusion [2].

Russell King said that we should have:

 - one decompressor which is the fastest
 - one decompressor for the highest compression ratio
 - one popular decompressor (eg conventional gzip)

If we have a replacement one for one of these, then it should do exactly
that: replace it.

The benchmark shows that an 8% increase in image size vs a 66% increase
in decompression speed compared to LZO(which has been known as the
fastest decompressor in the Kernel).  Therefore the "fast but may not be
small" compression title has clearly been taken by LZ4 [3].

[1] http://code.google.com/p/lz4/
[2] http://thread.gmane.org/gmane.linux.kbuild.devel/9157
[3] http://thread.gmane.org/gmane.linux.kbuild.devel/9347

LZ4 homepage: http://fastcompression.blogspot.com/p/lz4.html
LZ4 source repository: http://code.google.com/p/lz4/

Signed-off-by: Kyungsik Lee <kyungsik.lee@lge.com>
Signed-off-by: Yann Collet <yann.collet.73@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:30 -07:00
Chanho Min 4df87bb7b6 lib: add weak clz/ctz functions
Some architectures need __c[lt]z[sd]i2() for __builtin_c[lt]z[ll] and
that causes a build failure.  They can be implemented using the
fls()/__ffs() and overridden by linking arch-specific versions may not
be implemented yet.

This is required by "lib: add lz4 compressor module".

Reference: https://lkml.org/lkml/2013/4/18/603

Signed-off-by: Chanho Min <chanho.min@lge.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: "Darrick J. Wong" <djwong@us.ibm.com>
Cc: Bob Pearson <rpearson@systemfabricworks.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Herbert Xu <herbert@gondor.hengli.com.au>
Cc: Yann Collet <yann.collet.73@gmail.com>
Cc: Kyungsik Lee <kyungsik.lee@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:30 -07:00
Ard Biesheuvel 7d11965ddb lib/raid6: add ARM-NEON accelerated syndrome calculation
Rebased/reworked a patch contributed by Rob Herring that uses
NEON intrinsics to perform the RAID-6 syndrome calculations.
It uses the existing unroll.awk code to generate several
unrolled versions of which the best performing one is selected
at boot time.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Cc: hpa@linux.intel.com
2013-07-08 22:09:18 +01:00
Linus Torvalds b2c311075d Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu:
 - Do not idle omap device between crypto operations in one session.
 - Added sha224/sha384 shims for SSSE3.
 - More optimisations for camellia-aesni-avx2.
 - Removed defunct blowfish/twofish AVX2 implementations.
 - Added unaligned buffer self-tests.
 - Added PCLMULQDQ optimisation for CRCT10DIF.
 - Added support for Freescale's DCP co-processor
 - Misc fixes.

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (44 commits)
  crypto: testmgr - test hash implementations with unaligned buffers
  crypto: testmgr - test AEADs with unaligned buffers
  crypto: testmgr - test skciphers with unaligned buffers
  crypto: testmgr - check that entries in alg_test_descs are in correct order
  Revert "crypto: twofish - add AVX2/x86_64 assembler implementation of twofish cipher"
  Revert "crypto: blowfish - add AVX2/x86_64 implementation of blowfish cipher"
  crypto: camellia-aesni-avx2 - tune assembly code for more performance
  hwrng: bcm2835 - fix MODULE_LICENSE tag
  hwrng: nomadik - use clk_prepare_enable()
  crypto: picoxcell - replace strict_strtoul() with kstrtoul()
  crypto: dcp - Staticize local symbols
  crypto: dcp - Use NULL instead of 0
  crypto: dcp - Use devm_* APIs
  crypto: dcp - Remove redundant platform_set_drvdata()
  hwrng: use platform_{get,set}_drvdata()
  crypto: omap-aes - Don't idle/start AES device between Encrypt operations
  crypto: crct10dif - Use PTR_RET
  crypto: ux500 - Cocci spatch "resource_size.spatch"
  crypto: sha256_ssse3 - add sha224 support
  crypto: sha512_ssse3 - add sha384 support
  ...
2013-07-05 12:12:33 -07:00
Linus Torvalds 80cc38b163 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina:
 "The usual stuff from trivial tree"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (34 commits)
  treewide: relase -> release
  Documentation/cgroups/memory.txt: fix stat file documentation
  sysctl/net.txt: delete reference to obsolete 2.4.x kernel
  spinlock_api_smp.h: fix preprocessor comments
  treewide: Fix typo in printk
  doc: device tree: clarify stuff in usage-model.txt.
  open firmware: "/aliasas" -> "/aliases"
  md: bcache: Fixed a typo with the word 'arithmetic'
  irq/generic-chip: fix a few kernel-doc entries
  frv: Convert use of typedef ctl_table to struct ctl_table
  sgi: xpc: Convert use of typedef ctl_table to struct ctl_table
  doc: clk: Fix incorrect wording
  Documentation/arm/IXP4xx fix a typo
  Documentation/networking/ieee802154 fix a typo
  Documentation/DocBook/media/v4l fix a typo
  Documentation/video4linux/si476x.txt fix a typo
  Documentation/virtual/kvm/api.txt fix a typo
  Documentation/early-userspace/README fix a typo
  Documentation/video4linux/soc-camera.txt fix a typo
  lguest: fix CONFIG_PAE -> CONFIG_x86_PAE in comment
  ...
2013-07-04 11:40:58 -07:00
Linus Torvalds e61aca5158 Merge branch 'kconfig-diet' from Dave Hansen
Merge Kconfig menu diet patches from Dave Hansen:
 "I think the "Kernel Hacking" menu has gotten a bit out of hand.  It is
  over 120 lines long on my system with everything enabled and options
  are scattered around it haphazardly.

        http://sr71.net/~dave/linux/kconfig-horror.png

  Let's try to introduce some sanity.  This set takes that 120 lines
  down to 55 and makes it vastly easier to find some things.  It's a
  start.

  This set stands on its own, but there is plenty of room for follow-up
  patches.  The arch-specific debug options still end up getting stuck
  in the top-level "kernel hacking" menu.  OPTIMIZE_INLINING, for
  instance, could obviously go in to the "compiler options" menu, but
  the fact that it is defined in arch/ in a separate Kconfig file keeps
  it on its own for the moment.

  The Signed-off-by's in here look funky.  I changed employers while
  working on this set, so I have signoffs from both email addresses"

* emailed patches from Dave Hansen <dave@sr71.net>:
  hang and lockup detection menu
  kconfig: consolidate printk options
  group locking debugging options
  consolidate compilation option configs
  consolidate runtime testing configs
  order memory debugging Kconfig options
  consolidate per-arch stack overflow debugging options
2013-07-04 11:25:51 -07:00
Dave Hansen 92aef8fbab hang and lockup detection menu
The hard/softlockup and hung-task entries take up 6 lines
of screen real-estate when enabled.  I bet folks don't
mess with these _that_ often, so move them in a group
down a level.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-04 11:25:39 -07:00
Dave Hansen 604ff0dceb kconfig: consolidate printk options
Same deal, take the printk-related things and hide them in a menu.
This takes another 4 items out of the top-level menu.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-04 11:25:39 -07:00
Dave Hansen 9eade16b41 group locking debugging options
Original posting:

	http://lkml.kernel.org/r/20121214184208.D9E5804D@kernel.stglabs.ibm.com

There are quite a few of these, and we want to make sure that
there is one-stop-shopping for lock debugging.

Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-04 11:25:39 -07:00
Dave Hansen 6dfc06651b consolidate compilation option configs
Original Post:

	http://lkml.kernel.org/r/20121214184207.6E00DDEC@kernel.stglabs.ibm.com

Again, trying to come up with some common themes of the stuff in
the kernel hacking menu...  There are quite a few options to
tweak compilation in some way, or perform extra compile-time
checks.  Give them their own menu.

The diff here looks a bit funny... makes it look like I'm
moving debugfs even though I'm actually moving the options on
either side of it.

Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-04 11:25:39 -07:00
Dave Hansen 881c514954 consolidate runtime testing configs
Original posting:

	http://lkml.kernel.org/r/20121214184206.FC11422F@kernel.stglabs.ibm.com

These runtime tests are great, except that there are a lot of them,
and they are very rarely needed.  Give them their own menu so that
only the folks who need them will have to go looking for them.

Note that there are some other runtime tests that are not in here,
like for RCU or locking.  This menu should only be used for tests
that do not have a more appropriate home.

Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-04 11:25:39 -07:00
Dave Hansen 0610c8a8a2 order memory debugging Kconfig options
Original posting:

	http://lkml.kernel.org/r/20121214184203.37E6C724@kernel.stglabs.ibm.com

There are a *LOT* of memory debugging options.  They are just scattered
all over the "Kernel Hacking" menu.  Sure, "memory debugging" is a very
vague term and it's going to be hard to make absolute rules about what
goes in here, but this has to be better than what we had before.

This does, however, leave out the architecture-specific memory
debugging options (like x86's DEBUG_SET_MODULE_RONX).  There would need
to be some substantial changes to move those in here.  Kconfig can not
easily mix arch-specific and generic options together: it really
requires a file per-architecture, and I think having an
arch/foo/Kconfig.debug-memory might be taking things a bit too far

Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-04 11:25:39 -07:00
Dave Hansen d1a1dc0be8 consolidate per-arch stack overflow debugging options
Original posting:

	http://lkml.kernel.org/r/20121214184202.F54094D9@kernel.stglabs.ibm.com

Several architectures have similar stack debugging config options.
They all pretty much do the same thing, some with slightly
differing help text.

This patch changes the architectures to instead enable a Kconfig
boolean, and then use that boolean in the generic Kconfig.debug
to present the actual menu option.  This removes a bunch of
duplication and adds consistency across arches.

Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
Reviewed-by: H. Peter Anvin <hpa@zytor.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com> [for tile]
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-04 11:25:39 -07:00
Linus Torvalds 7f0ef0267e Merge branch 'akpm' (updates from Andrew Morton)
Merge first patch-bomb from Andrew Morton:
 - various misc bits
 - I'm been patchmonkeying ocfs2 for a while, as Joel and Mark have been
   distracted.  There has been quite a bit of activity.
 - About half the MM queue
 - Some backlight bits
 - Various lib/ updates
 - checkpatch updates
 - zillions more little rtc patches
 - ptrace
 - signals
 - exec
 - procfs
 - rapidio
 - nbd
 - aoe
 - pps
 - memstick
 - tools/testing/selftests updates

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (445 commits)
  tools/testing/selftests: don't assume the x bit is set on scripts
  selftests: add .gitignore for kcmp
  selftests: fix clean target in kcmp Makefile
  selftests: add .gitignore for vm
  selftests: add hugetlbfstest
  self-test: fix make clean
  selftests: exit 1 on failure
  kernel/resource.c: remove the unneeded assignment in function __find_resource
  aio: fix wrong comment in aio_complete()
  drivers/w1/slaves/w1_ds2408.c: add magic sequence to disable P0 test mode
  drivers/memstick/host/r592.c: convert to module_pci_driver
  drivers/memstick/host/jmb38x_ms: convert to module_pci_driver
  pps-gpio: add device-tree binding and support
  drivers/pps/clients/pps-gpio.c: convert to module_platform_driver
  drivers/pps/clients/pps-gpio.c: convert to devm_* helpers
  drivers/parport/share.c: use kzalloc
  Documentation/accounting/getdelays.c: avoid strncpy in accounting tool
  aoe: update internal version number to v83
  aoe: update copyright date
  aoe: perform I/O completions in parallel
  ...
2013-07-03 17:12:13 -07:00
Jean Delvare dd04b452f5 idr: print a stack dump after ida_remove warning
We print a dump stack after idr_remove warning.  This is useful to find
the faulty piece of code.  Let's do the same for ida_remove, as it would
be equally useful there.

[akpm@linux-foundation.org: convert the open-coded printk+dump_stack into WARN()]
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Cc: Tejun Heo <tj@kernel.org>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:08:04 -07:00
Fan Du 64df3071a9 lib/percpu_counter.c: __this_cpu_write() doesn't need to be protected by spinlock
__this_cpu_write doesn't need to be protected by spinlock, AS we are doing
per cpu write with preempt disabled.  And another reason to remove
__this_cpu_write outside of spinlock: __percpu_counter_sum is not an
accurate counter.

Signed-off-by: Fan Du <fan.du@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:43 -07:00
Alex Thorlton b58d977432 dump_stack: serialize the output from dump_stack()
Add functionality to serialize the output from dump_stack() to avoid
mangling of the output when dump_stack is called simultaneously from
multiple cpus.

[akpm@linux-foundation.org: fix comment indenting, avoid inclusion of <asm/> files - use <linux/> where possiblem fix uniprocessor build (__dump_stack undefined), remove unneeded ifdef around smp.h inclusion]
Signed-off-by: Alex Thorlton <athorlton@sgi.com>
Reported-by: Russ Anderson <rja@sgi.com>
Reviewed-by: Robin Holt <holt@sgi.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:41 -07:00
Linus Torvalds ab53485739 Merge branch 'exotic-arch-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k
Pull "exotic" arch fixes from Geert Uytterhoeven:
 "This is a collection of several exotic architecture fixes, and a few
  other fixes for issues that were detected while doing the former"

* 'exotic-arch-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k: (35 commits)
  lib: Move fonts from drivers/video/console/ to lib/fonts/
  console/font: Refactor font support code selection logic
  Revert "staging/solo6x10: depend on CONFIG_FONTS"
  input: cros_ec_keyb_clear_keyboard() depends on CONFIG_PM_SLEEP
  score: Wire up asm-generic/xor.h
  score: Remove unneeded <asm/dma-mapping.h>
  openrisc: Wire up asm-generic/xor.h
  h8300/boot: Use POSIX "$((..))" instead of bashism "$[...]"
  h8300: Mark H83002 and H83048 CPU support broken
  h8300: Switch h8300 to drivers/Kconfig
  h8300: Limit timer channel ranges in Kconfig
  h8300: Wire up asm-generic/xor.h
  h8300: Fill the system call table using a CALL() macro
  h8300: Fix <asm/tlb.h>
  h8300: Hardcode symbol prefixes in asm sources
  h8300: add missing definition for read_barries_depends()
  frv: head.S - Remove commented-out initialization code
  cris: Wire up asm-generic/vga.h
  parport: disable PC-style parallel port support on cris
  console: Disable VGA text console support on cris
  ...
2013-07-03 11:12:08 -07:00
Linus Torvalds 13cc560138 Merge branch 'for-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
Pull per-cpu changes from Tejun Heo:
 "This pull request contains Kent's per-cpu reference counter.  It has
  gone through several iterations since the last time and the dynamic
  allocation is gone.

  The usual usage is relatively straight-forward although async kill
  confirm interface, which is not used int most cases, is somewhat icky.
  There also are some interface concerns - e.g.  I'm not sure about
  passing in @relesae callback during init as that becomes funny when we
  later implement synchronous kill_and_drain - but nothing too serious
  and it's quite useable now.

  cgroup_subsys_state refcnting has already been converted and we should
  convert module refcnt (Kent?)"

* 'for-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu-refcount: use RCU-sched insted of normal RCU
  percpu-refcount: implement percpu_tryget() along with percpu_ref_kill_and_confirm()
  percpu-refcount: implement percpu_ref_cancel_init()
  percpu-refcount: add __must_check to percpu_ref_init() and don't use ACCESS_ONCE() in percpu_ref_kill_rcu()
  percpu-refcount: cosmetic updates
  percpu-refcount: consistently use plain (non-sched) RCU
  percpu-refcount: Don't use silly cmpxchg()
  percpu: implement generic percpu refcounting
2013-07-02 19:52:14 -07:00
Linus Torvalds 0c46d68d19 Merge branch 'core-mutexes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull WW mutex support from Ingo Molnar:
 "This tree adds support for wound/wait style locks, which the graphics
  guys would like to make use of in the TTM graphics subsystem.

  Wound/wait mutexes are used when other multiple lock acquisitions of a
  similar type can be done in an arbitrary order.  The deadlock handling
  used here is called wait/wound in the RDBMS literature: The older
  tasks waits until it can acquire the contended lock.  The younger
  tasks needs to back off and drop all the locks it is currently
  holding, ie the younger task is wounded.

  See this LWN.net description of W/W mutexes:

     https://lwn.net/Articles/548909/

  The comments there outline specific usecases for this facility (which
  have already been implemented for the DRM tree).

  Also see Documentation/ww-mutex-design.txt for more details"

* 'core-mutexes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking-selftests: Handle unexpected failures more strictly
  mutex: Add more w/w tests to test EDEADLK path handling
  mutex: Add more tests to lib/locking-selftest.c
  mutex: Add w/w tests to lib/locking-selftest.c
  mutex: Add w/w mutex slowpath debugging
  mutex: Add support for wound/wait style locks
  arch: Make __mutex_fastpath_lock_retval return whether fastpath succeeded or not
2013-07-02 16:09:13 -07:00
Linus Torvalds 22237d5a58 ARM SoC non-cricitical bug fixes
These are various bug fixes that were not considered important enough
 for merging into 3.10. The majority of the ARM fixes are for the OMAP
 and at91 platforms, and there is another set of bug fixes for device
 drivers that resolve 'randconfig' build errors and that the subsystem
 maintainers either did not pick up or preferred to get merged through
 the arm-soc tree.
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Merge tag 'fixes-non-critical-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC non-cricitical bug fixes from Arnd Bergmann:
 "These are various bug fixes that were not considered important enough
  for merging into 3.10.

  The majority of the ARM fixes are for the OMAP and at91 platforms, and
  there is another set of bug fixes for device drivers that resolve
  'randconfig' build errors and that the subsystem maintainers either
  did not pick up or preferred to get merged through the arm-soc tree."

* tag 'fixes-non-critical-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (43 commits)
  ARM: at91/PMC: use at91_usb_rate() for UTMI PLL
  ARM: at91/PMC: fix at91sam9n12 USB FS init
  ARM: at91/PMC: at91sam9n12 family has a PLLB
  ARM: at91/PMC: sama5d3 family doesn't have a PLLB
  ARM: tegra: fix section mismatch in tegra_pmc_parse_dt
  ARM: mxs: don't select HAVE_PWM
  ARM: mxs: stub out mxs_pm_init for !CONFIG_PM
  cpuidle: calxeda: select ARM_CPU_SUSPEND
  ARM: mvebu: fix length of ethernet registers in mv78260 dtsi
  ARM: at91: cpuidle: Fix target_residency
  ARM: at91: fix at91_extern_irq usage for non-dt boards
  ARM: sirf: use CONFIG_SIRF rather than CONFIG_PRIMA2 where necessary
  clocksource: kona: adapt to CLOCKSOURCE_OF_DECLARE change
  X.509: do not emit any informational output
  mtd: omap2: allow bulding as a module
  [SCSI] nsp32: use mdelay instead of large udelay constants
  hwrng: bcm2835: fix MODULE_LICENSE tag
  ARM: at91: Change the internal SRAM memory type MT_MEMORY_NONCACHED
  ARM: at91: Fix link breakage when !CONFIG_PHYLIB
  MAINTAINERS: Add exynos filename match to ARM/S5P EXYNOS ARM ARCHITECTURES
  ...
2013-07-02 13:24:47 -07:00
Linus Torvalds fc76a258d4 Driver core patches for 3.11-rc1
Here's the big driver core merge for 3.11-rc1
 
 Lots of little things, and larger firmware subsystem updates, all
 described in the shortlog.  Nice thing here is that we finally get rid
 of CONFIG_HOTPLUG, after 10+ years, thanks to Stephen Rohtwell (it had
 been always on for a number of kernel releases, now it's just removed.)
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here's the big driver core merge for 3.11-rc1

  Lots of little things, and larger firmware subsystem updates, all
  described in the shortlog.  Nice thing here is that we finally get rid
  of CONFIG_HOTPLUG, after 10+ years, thanks to Stephen Rohtwell (it had
  been always on for a number of kernel releases, now it's just
  removed)"

* tag 'driver-core-3.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (27 commits)
  driver core: device.h: fix doc compilation warnings
  firmware loader: fix another compile warning with PM_SLEEP unset
  build some drivers only when compile-testing
  firmware loader: fix compile warning with PM_SLEEP set
  kobject: sanitize argument for format string
  sysfs_notify is only possible on file attributes
  firmware loader: simplify holding module for request_firmware
  firmware loader: don't export cache_firmware and uncache_firmware
  drivers/base: Use attribute groups to create sysfs memory files
  firmware loader: fix compile warning
  firmware loader: fix build failure with !CONFIG_FW_LOADER_USER_HELPER
  Documentation: Updated broken link in HOWTO
  Finally eradicate CONFIG_HOTPLUG
  driver core: firmware loader: kill FW_ACTION_NOHOTPLUG requests before suspend
  driver core: firmware loader: don't cache FW_ACTION_NOHOTPLUG firmware
  Documentation: Tidy up some drivers/base/core.c kerneldoc content.
  platform_device: use a macro instead of platform_driver_register
  firmware: move EXPORT_SYMBOL annotations
  firmware: Avoid deadlock of usermodehelper lock at shutdown
  dell_rbu: Select CONFIG_FW_LOADER_USER_HELPER explicitly
  ...
2013-07-02 11:44:19 -07:00
Daniel Borkmann 1067964305 lib: vsprintf: add IPv4/v6 generic %p[Ii]S[pfs] format specifier
In order to avoid making code that deals with printing both, IPv4 and
IPv6 addresses, unnecessary complicated as for example ...

  if (sa.sa_family == AF_INET6)
    printk("... %pI6 ...", ..sin6_addr);
  else
    printk("... %pI4 ...", ..sin_addr.s_addr);

... it would be better to introduce a format specifier that can deal
with those kind of situations internally; just as we have a "struct
sockaddr" for generic mapping into "struct sockaddr_in" or "struct
sockaddr_in6" as e.g. done in "union sctp_addr". Then, we could
reduce the above statement into something like:

  printk("... %pIS ..", &sockaddr);

In case our pointer is NULL, pointer() then deals with that already at
an earlier point in time internally. While we're at it, support for both
%piS/%pIS, where 'S' stands for sockaddr, comes (almost) for free.

Additionally to that, postfix specifiers 'p', 'f' and 's' are supported
as suggested and initially implemented in 2009 by Joe Perches [1].
Handling of those additional specifiers orientate on the initial RFC that
was proposed. Also we support IPv6 compressed format specified by 'c' and
various other IPv4 extensions as stated in the documentation part.

Likely, there are many other areas than just SCTP in the kernel to make
use of this extension as well.

 [1] http://patchwork.ozlabs.org/patch/31480/

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
CC: Joe Perches <joe@perches.com>
CC: linux-kernel@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-01 23:22:13 -07:00
Geert Uytterhoeven ee89bd6bc7 lib: Move fonts from drivers/video/console/ to lib/fonts/
Several drivers need font support independent of CONFIG_VT, cfr. commit
9cbce8d7e1dae0744ca4f68d62aa7de18196b6f4, "console/font: Refactor font
support code selection logic").
Hence move the fonts and their support logic from drivers/video/console/ to
its own library directory lib/fonts/.
This also allows to limit processing of drivers/video/console/Makefile to
CONFIG_VT=y again.

[Kevin Hilman <khilman@linaro.org>: Update arch/arm/boot/compressed/Makefile]
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-06-28 10:28:22 +02:00
Maarten Lankhorst 166989e366 locking-selftests: Handle unexpected failures more strictly
When CONFIG_PROVE_LOCKING is not enabled, more tests are
expected to pass unexpectedly, but there no tests that should
start to fail that pass with CONFIG_PROVE_LOCKING enabled.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Cc: rostedt@goodmis.org
Cc: daniel@ffwll.ch
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20130620113151.4001.77963.stgit@patser
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-26 12:10:59 +02:00
Maarten Lankhorst f3cf139efa mutex: Add more w/w tests to test EDEADLK path handling
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Cc: rostedt@goodmis.org
Cc: daniel@ffwll.ch
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20130620113141.4001.54331.stgit@patser
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-26 12:10:58 +02:00
Maarten Lankhorst 2fe3d4b149 mutex: Add more tests to lib/locking-selftest.c
None of the ww_mutex codepaths should be taken in the 'normal'
mutex calls. The easiest way to verify this is by using the
normal mutex calls, and making sure o.ctx is unmodified.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Cc: robclark@gmail.com
Cc: rostedt@goodmis.org
Cc: daniel@ffwll.ch
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20130620113130.4001.45423.stgit@patser
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-26 12:10:57 +02:00
Maarten Lankhorst 1de994452f mutex: Add w/w tests to lib/locking-selftest.c
This stresses the lockdep code in some ways specifically useful
to ww_mutexes. It adds checks for most of the common locking
errors.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Cc: robclark@gmail.com
Cc: rostedt@goodmis.org
Cc: daniel@ffwll.ch
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20130620113124.4001.23186.stgit@patser
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-26 12:10:57 +02:00
Daniel Vetter 2301002769 mutex: Add w/w mutex slowpath debugging
Injects EDEADLK conditions at pseudo-random interval, with
exponential backoff up to UINT_MAX (to ensure that every lock
operation still completes in a reasonable time).

This way we can test the wound slowpath even for ww mutex users
where contention is never expected, and the ww deadlock
avoidance algorithm is only needed for correctness against
malicious userspace. An example would be protecting kernel
modesetting properties, which thanks to single-threaded X isn't
really expected to contend, ever.

I've looked into using the CONFIG_FAULT_INJECTION
infrastructure, but decided against it for two reasons:

- EDEADLK handling is mandatory for ww mutex users and should
  never affect the outcome of a syscall. This is in contrast to -ENOMEM
  injection. So fine configurability isn't required.

- The fault injection framework only allows to set a simple
  probability for failure. Now the probability that a ww mutex acquire
  stage with N locks will never complete (due to too many injected
  EDEADLK backoffs) is zero. But the expected number of ww_mutex_lock
  operations for the completely uncontended case would be O(exp(N)).
  The per-acuiqire ctx exponential backoff solution choosen here only
  results in O(log N) overhead due to injection and so O(log N * N)
  lock operations. This way we can fail with high probability (and so
  have good test coverage even for fancy backoff and lock acquisition
  paths) without running into patalogical cases.

Note that EDEADLK will only ever be injected when we managed to
acquire the lock. This prevents any behaviour changes for users
which rely on the EALREADY semantics.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Cc: rostedt@goodmis.org
Cc: daniel@ffwll.ch
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20130620113117.4001.21681.stgit@patser
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-26 12:10:56 +02:00
Maarten Lankhorst 040a0a3710 mutex: Add support for wound/wait style locks
Wound/wait mutexes are used when other multiple lock
acquisitions of a similar type can be done in an arbitrary
order. The deadlock handling used here is called wait/wound in
the RDBMS literature: The older tasks waits until it can acquire
the contended lock. The younger tasks needs to back off and drop
all the locks it is currently holding, i.e. the younger task is
wounded.

For full documentation please read Documentation/ww-mutex-design.txt.

References: https://lwn.net/Articles/548909/
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Rob Clark <robdclark@gmail.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Cc: rostedt@goodmis.org
Cc: daniel@ffwll.ch
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/51C8038C.9000106@canonical.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-06-26 12:10:56 +02:00
Markos Chandras 25c87eae17 lib/Kconfig.debug: Restrict FRAME_POINTER for MIPS
FAULT_INJECTION_STACKTRACE_FILTER selects FRAME_POINTER but
that symbol is not available for MIPS.

Fixes the following problem on a randconfig:
warning: (LOCKDEP && FAULT_INJECTION_STACKTRACE_FILTER && LATENCYTOP &&
 KMEMCHECK) selects FRAME_POINTER which has unmet direct dependencies
(DEBUG_KERNEL && (CRIS || M68K || FRV || UML || AVR32 || SUPERH || BLACKFIN ||
MN10300 || METAG) || ARCH_WANT_FRAME_POINTERS)

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Acked-by: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5441/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-06-21 18:07:01 +02:00
Arnd Bergmann a857c6e7d5 X.509: do not emit any informational output
When building a kernel using 'make -s', I expect to see an empty output,
except for build warnings and errors. The build_OID_registry code
always prints one line when run, which is not helpful to most people
building the kernels, and which makes it harder to automatically
check for build warnings.

Let's just remove the one line output.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
2013-06-19 17:54:06 +02:00
Masanari Iida 278cee0515 treewide: Fix typo in printk
Correct spelling typo in printk within various drivers.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-06-18 13:48:45 +02:00
Greg Kroah-Hartman bb07b00be7 Merge 3.10-rc6 into driver-core-next
We want these fixes here too.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-17 16:57:20 -07:00
Greg Kroah-Hartman 0e496b8e84 Merge 3.10-rc6 into char-misc-next
We want the fixes in here.
2013-06-17 11:54:25 -07:00
Tejun Heo a4244454df percpu-refcount: use RCU-sched insted of normal RCU
percpu-refcount was incorrectly using preempt_disable/enable() for RCU
critical sections against call_rcu().  6a24474da8 ("percpu-refcount:
consistently use plain (non-sched) RCU") fixed it by converting the
preepmtion operations with rcu_read_[un]lock() citing that there isn't
any advantage in using sched-RCU over using the usual one; however,
rcu_read_[un]lock() for the preemptible RCU implementation -
CONFIG_TREE_PREEMPT_RCU, chosen when CONFIG_PREEMPT - are slightly
more expensive than preempt_disable/enable().

In a contrived microbench which repeats the followings,

 - percpu_ref_get()
 - copy 32 bytes of data into percpu buffer
 - percpu_put_get()
 - copy 32 bytes of data into percpu buffer

rcu_read_[un]lock() used in percpu_ref_get/put() makes it go slower by
about 15% when compared to using sched-RCU.

As the RCU critical sections are extremely short, using sched-RCU
shouldn't have any latency implications.  Convert to RCU-sched.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Kent Overstreet <koverstreet@google.com>
Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Rusty Russell <rusty@rustcorp.com.au>
2013-06-16 16:12:26 -07:00
Tejun Heo dbece3a0f1 percpu-refcount: implement percpu_tryget() along with percpu_ref_kill_and_confirm()
Implement percpu_tryget() which stops giving out references once the
percpu_ref is visible as killed.  Because the refcnt is per-cpu,
different CPUs will start to see a refcnt as killed at different
points in time and tryget() may continue to succeed on subset of cpus
for a while after percpu_ref_kill() returns.

For use cases where it's necessary to know when all CPUs start to see
the refcnt as dead, percpu_ref_kill_and_confirm() is added.  The new
function takes an extra argument @confirm_kill which is invoked when
the refcnt is guaranteed to be viewed as killed on all CPUs.

While this isn't the prettiest interface, it doesn't force synchronous
wait and is much safer than requiring the caller to do its own
call_rcu().

v2: Patch description rephrased to emphasize that tryget() may
    continue to succeed on some CPUs after kill() returns as suggested
    by Kent.

v3: Function comment in percpu_ref_kill_and_confirm() updated warning
    people to not depend on the implied RCU grace period from the
    confirm callback as it's an implementation detail.

Signed-off-by: Tejun Heo <tj@kernel.org>
Slightly-Grumpily-Acked-by: Kent Overstreet <koverstreet@google.com>
2013-06-13 19:23:53 -07:00
Tejun Heo bc497bd33b percpu-refcount: implement percpu_ref_cancel_init()
Normally, percpu_ref_init() initializes and percpu_ref_kill()
initiates destruction which completes asynchronously.  The
asynchronous destruction can be problematic in init failure path where
the caller wants to destroy half-constructed object - distinguishing
half-constructed objects from the usual release method can be painful
for complex objects.

This patch implements percpu_ref_cancel_init() which synchronously
destroys the percpu_ref without invoking release.  To avoid
unintentional misuses, the function requires the ref to have finished
percpu_ref_init() but never used and triggers WARN otherwise.

v2: Explain the weird name and usage restriction in the function
    comment.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Kent Overstreet <koverstreet@google.com>
2013-06-13 11:08:27 -07:00
Tejun Heo acac7883ee percpu-refcount: add __must_check to percpu_ref_init() and don't use ACCESS_ONCE() in percpu_ref_kill_rcu()
Two small changes.

* Unlike most init functions, percpu_ref_init() allocates memory and
  may fail.  Let's mark it with __must_check in case the caller
  forgets.

* percpu_ref_kill_rcu() is unnecessarily using ACCESS_ONCE() to
  dereference @ref->pcpu_count, which can be misleading.  The pointer
  is guaranteed to be valid and visible and can't change underneath
  the function.  Drop ACCESS_ONCE().

Signed-off-by: Tejun Heo <tj@kernel.org>
2013-06-13 11:08:26 -07:00
Tejun Heo ac899061a9 percpu-refcount: cosmetic updates
* s/percpu_ref_release/percpu_ref_func_t/ as it's customary to have _t
  postfix for types and the type is gonna be used for a different type
  of callback too.

* Add @ARG to function comments.

* Drop unnecessary and unaligned indentation from percpu_ref_init()
  function comment.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Kent Overstreet <koverstreet@google.com>
2013-06-12 20:43:06 -07:00
Chen Gang 5402b8047b lib/mpi/mpicoder.c: looping issue, need stop when equal to zero, found by 'EXTRA_FLAGS=-W'.
For 'while' looping, need stop when 'nbytes == 0', or will cause issue.
('nbytes' is size_t which is always bigger or equal than zero).

The related warning: (with EXTRA_CFLAGS=-W)

  lib/mpi/mpicoder.c:40:2: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]

Signed-off-by: Chen Gang <gang.chen@asianux.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-06-12 16:29:44 -07:00
Kees Cook b7165ebbf0 kobject: sanitize argument for format string
Unlike kobject_set_name(), the kset_create_and_add() interface does not
provide a way to use format strings, so make sure that the interface
cannot be abused accidentally. It looks like all current callers use
static strings, so there's no existing flaw.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-07 16:05:50 -07:00
Andy Shevchenko 4cd5773a2a net: core: move mac_pton() to lib/net_utils.c
Since we have at least one user of this function outside of CONFIG_NET
scope, we have to provide this function independently. The proposed
solution is to move it under lib/net_utils.c with corresponding
configuration variable and select wherever it is needed.

Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-05 12:00:27 -07:00
Herbert Xu 67822649d7 crypto: crct10dif - Use PTR_RET
lib/crc-t10dif.c:42:1-3: WARNING: PTR_RET can be used

 Use PTR_RET rather than if(IS_ERR(...)) + PTR_ERR

Generated by: coccinelle/api/ptr_ret.cocci

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-06-05 16:27:51 +08:00
Kent Overstreet c1ae6e9b4d percpu-refcount: Don't use silly cmpxchg()
The cmpxchg() was just to ensure the debug check didn't race, which was
a bit excessive. The caller is supposed to do the appropriate
synchronization, which means percpu_ref_kill() can just do a simple
store.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2013-06-03 16:04:04 -07:00
Kent Overstreet 215e262f2a percpu: implement generic percpu refcounting
This implements a refcount with similar semantics to
atomic_get()/atomic_dec_and_test() - but percpu.

It also implements two stage shutdown, as we need it to tear down the
percpu counts.  Before dropping the initial refcount, you must call
percpu_ref_kill(); this puts the refcount in "shutting down mode" and
switches back to a single atomic refcount with the appropriate
barriers (synchronize_rcu()).

It's also legal to call percpu_ref_kill() multiple times - it only
returns true once, so callers don't have to reimplement shutdown
synchronization.

[akpm@linux-foundation.org: fix build]
[akpm@linux-foundation.org: coding-style tweak]
Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: Zach Brown <zab@redhat.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Reviewed-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Tejun Heo <tj@kernel.org>
2013-06-03 15:36:41 -07:00
Seth Jennings 3a76e5e09f debugfs: add get/set for atomic types
debugfs currently lack the ability to create attributes
that set/get atomic_t values.

This patch adds support for this through a new
debugfs_create_atomic_t() function.

Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-03 13:55:01 -07:00
Steven Rostedt 360603a1be sprintf: hex_string(): fix comment
hex_string() had a typo in a comment.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-05-29 01:14:46 +02:00
Helge Deller 70ef5578dd MPILIB: disable usage of floating point registers on parisc
The umul_ppmm() macro for parisc uses the xmpyu assembler statement
which does calculation via a floating point register.

But usage of floating point registers inside the Linux kernel are not
allowed and gcc will stop compilation due to the -mdisable-fpregs
compiler option.

Fix this by disabling the umul_ppmm() and udiv_qrnnd() macros. The
mpilib will then use the generic built-in implementations instead.

Signed-off-by: Helge Deller <deller@gmx.de>
2013-05-24 22:30:11 +02:00
Linus Torvalds c7153d0643 Driver core fixes for 3.10-rc2
Here are 3 tiny driver core fixes for 3.10-rc2.
 
 A needed symbol export, a change to make it easier to track down
 offending sysfs files with incorrect attributes, and a klist bugfix.
 
 All have been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 Version: GnuPG v2.0.19 (GNU/Linux)
 
 iEYEABECAAYFAlGePdAACgkQMUfUDdst+ynX3wCfbodTGeimy2GTnc5psVgXV/x4
 bz8AnR6G/JNCw54meAJ5UlYJRj7Dwo09
 =MNP/
 -----END PGP SIGNATURE-----

Merge tag 'driver-core-3.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core fixes from Greg Kroah-Hartman:
 "Here are 3 tiny driver core fixes for 3.10-rc2.

  A needed symbol export, a change to make it easier to track down
  offending sysfs files with incorrect attributes, and a klist bugfix.

  All have been in linux-next for a while"

* tag 'driver-core-3.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  klist: del waiter from klist_remove_waiters before wakeup waitting process
  driver core: print sysfs attribute name when warning about bogus permissions
  driver core: export subsys_virtual_register
2013-05-23 09:27:08 -07:00
Randy Dunlap b4d3ba3346 lib: make iovec obj instead of lib
Fix build error io vmw_vmci.ko when CONFIG_VMWARE_VMCI=m by chaning
iovec.o from lib-y to obj-y.

  ERROR: "memcpy_toiovec" [drivers/misc/vmw_vmci/vmw_vmci.ko] undefined!
  ERROR: "memcpy_fromiovec" [drivers/misc/vmw_vmci/vmw_vmci.ko] undefined!

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-23 09:17:11 -07:00
wang, biao ac5a2962b0 klist: del waiter from klist_remove_waiters before wakeup waitting process
There is a race between klist_remove and klist_release. klist_remove
uses a local var waiter saved on stack. When klist_release calls
wake_up_process(waiter->process) to wake up the waiter, waiter might run
immediately and reuse the stack. Then, klist_release calls
list_del(&waiter->list) to change previous
wait data and cause prior waiter thread corrupt.

The patch fixes it against kernel 3.9.

Signed-off-by: wang, biao <biao.wang@intel.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-21 10:16:39 -07:00
Tim Chen 2d31e518a4 crypto: crct10dif - Wrap crc_t10dif function all to use crypto transform framework
When CRC T10 DIF is calculated using the crypto transform framework, we
wrap the crc_t10dif function call to utilize it.  This allows us to
take advantage of any accelerated CRC T10 DIF transform that is
plugged into the crypto framework.

Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-05-20 20:11:01 +08:00
Rusty Russell d2f83e9078 Hoist memcpy_fromiovec/memcpy_toiovec into lib/
ERROR: "memcpy_fromiovec" [drivers/vhost/vhost_scsi.ko] undefined!

That function is only present with CONFIG_NET.  Turns out that
crypto/algif_skcipher.c also uses that outside net, but it actually
needs sockets anyway.

In addition, commit 6d4f0139d6 added
CONFIG_NET dependency to CONFIG_VMCI for memcpy_toiovec, so hoist
that function and revert that commit too.

socket.h already includes uio.h, so no callers need updating; trying
only broke things fo x86_64 randconfig (thanks Fengguang!).

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-05-20 10:24:22 +09:30
Linus Torvalds ebb3727779 Merge branch 'for-3.10/drivers' of git://git.kernel.dk/linux-block
Pull block driver updates from Jens Axboe:
 "It might look big in volume, but when categorized, not a lot of
  drivers are touched.  The pull request contains:

   - mtip32xx fixes from Micron.

   - A slew of drbd updates, this time in a nicer series.

   - bcache, a flash/ssd caching framework from Kent.

   - Fixes for cciss"

* 'for-3.10/drivers' of git://git.kernel.dk/linux-block: (66 commits)
  bcache: Use bd_link_disk_holder()
  bcache: Allocator cleanup/fixes
  cciss: bug fix to prevent cciss from loading in kdump crash kernel
  cciss: add cciss_allow_hpsa module parameter
  drivers/block/mg_disk.c: add CONFIG_PM_SLEEP to suspend/resume functions
  mtip32xx: Workaround for unaligned writes
  bcache: Make sure blocksize isn't smaller than device blocksize
  bcache: Fix merge_bvec_fn usage for when it modifies the bvm
  bcache: Correctly check against BIO_MAX_PAGES
  bcache: Hack around stuff that clones up to bi_max_vecs
  bcache: Set ra_pages based on backing device's ra_pages
  bcache: Take data offset from the bdev superblock.
  mtip32xx: mtip32xx: Disable TRIM support
  mtip32xx: fix a smatch warning
  bcache: Disable broken btree fuzz tester
  bcache: Fix a format string overflow
  bcache: Fix a minor memory leak on device teardown
  bcache: Documentation updates
  bcache: Use WARN_ONCE() instead of __WARN()
  bcache: Add missing #include <linux/prefetch.h>
  ...
2013-05-08 11:51:05 -07:00
Davidlohr Bueso 9607a85b67 rwsem: check counter to avoid cmpxchg calls
This patch tries to reduce the amount of cmpxchg calls in the writer
failed path by checking the counter value first before issuing the
instruction.  If ->count is not set to RWSEM_WAITING_BIAS then there is
no point wasting a cmpxchg call.

Furthermore, Michel states "I suppose it helps due to the case where
someone else steals the lock while we're trying to acquire
sem->wait_lock."

Two very different workloads and machines were used to see how this
patch improves throughput: pgbench on a quad-core laptop and aim7 on a
large 8 socket box with 80 cores.

Some results comparing Michel's fast-path write lock stealing
(tps-rwsem) on a quad-core laptop running pgbench:

  | db_size | clients  |  tps-rwsem     |   tps-patch  |
  +---------+----------+----------------+--------------+
  | 160 MB   |       1 |           6906 |         9153 | + 32.5
  | 160 MB   |       2 |          15931 |        22487 | + 41.1%
  | 160 MB   |       4 |          33021 |        32503 |
  | 160 MB   |       8 |          34626 |        34695 |
  | 160 MB   |      16 |          33098 |        34003 |
  | 160 MB   |      20 |          31343 |        31440 |
  | 160 MB   |      30 |          28961 |        28987 |
  | 160 MB   |      40 |          26902 |        26970 |
  | 160 MB   |      50 |          25760 |        25810 |
  ------------------------------------------------------
  | 1.6 GB   |       1 |           7729 |         7537 |
  | 1.6 GB   |       2 |          19009 |        23508 | + 23.7%
  | 1.6 GB   |       4 |          33185 |        32666 |
  | 1.6 GB   |       8 |          34550 |        34318 |
  | 1.6 GB   |      16 |          33079 |        32689 |
  | 1.6 GB   |      20 |          31494 |        31702 |
  | 1.6 GB   |      30 |          28535 |        28755 |
  | 1.6 GB   |      40 |          27054 |        27017 |
  | 1.6 GB   |      50 |          25591 |        25560 |
  ------------------------------------------------------
  | 7.6 GB   |       1 |           6224 |         7469 | + 20.0%
  | 7.6 GB   |       2 |          13611 |        12778 |
  | 7.6 GB   |       4 |          33108 |        32927 |
  | 7.6 GB   |       8 |          34712 |        34878 |
  | 7.6 GB   |      16 |          32895 |        33003 |
  | 7.6 GB   |      20 |          31689 |        31974 |
  | 7.6 GB   |      30 |          29003 |        28806 |
  | 7.6 GB   |      40 |          26683 |        26976 |
  | 7.6 GB   |      50 |          25925 |        25652 |
  ------------------------------------------------------

For the aim7 worloads, they overall improved on top of Michel's
patchset.  For full graphs on how the rwsem series plus this patch
behaves on a large 8 socket machine against a vanilla kernel:

  http://stgolabs.net/rwsem-aim7-results.tar.gz

Signed-off-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 16:11:51 -07:00
Anatol Pomozov 2d864e4171 kref: minor cleanup
- make warning smp-safe
 - result of atomic _unless_zero functions should be checked by caller
   to avoid use-after-free error
 - trivial whitespace fix.

Link: https://lkml.org/lkml/2013/4/12/391

Tested: compile x86, boot machine and run xfstests
Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com>
[ Removed line-break, changed to use WARN_ON_ONCE()  - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 16:09:00 -07:00
Linus Torvalds c8de2fa4dc Merge branch 'rwsem-optimizations'
Merge rwsem optimizations from Michel Lespinasse:
 "These patches extend Alex Shi's work (which added write lock stealing
  on the rwsem slow path) in order to provide rwsem write lock stealing
  on the fast path (that is, without taking the rwsem's wait_lock).

  I have unfortunately been unable to push this through -next before due
  to Ingo Molnar / David Howells / Peter Zijlstra being busy with other
  things.  However, this has gotten some attention from Rik van Riel and
  Davidlohr Bueso who both commented that they felt this was ready for
  v3.10, and Ingo Molnar has said that he was OK with me pushing
  directly to you.  So, here goes :)

  Davidlohr got the following test results from pgbench running on a
  quad-core laptop:

    | db_size | clients  |  tps-vanilla   |   tps-rwsem  |
    +---------+----------+----------------+--------------+
    | 160 MB   |       1 |           5803 |         6906 | + 19.0%
    | 160 MB   |       2 |          13092 |        15931 |
    | 160 MB   |       4 |          29412 |        33021 |
    | 160 MB   |       8 |          32448 |        34626 |
    | 160 MB   |      16 |          32758 |        33098 |
    | 160 MB   |      20 |          26940 |        31343 | + 16.3%
    | 160 MB   |      30 |          25147 |        28961 |
    | 160 MB   |      40 |          25484 |        26902 |
    | 160 MB   |      50 |          24528 |        25760 |
    ------------------------------------------------------
    | 1.6 GB   |       1 |           5733 |         7729 | + 34.8%
    | 1.6 GB   |       2 |           9411 |        19009 | + 101.9%
    | 1.6 GB   |       4 |          31818 |        33185 |
    | 1.6 GB   |       8 |          33700 |        34550 |
    | 1.6 GB   |      16 |          32751 |        33079 |
    | 1.6 GB   |      20 |          30919 |        31494 |
    | 1.6 GB   |      30 |          28540 |        28535 |
    | 1.6 GB   |      40 |          26380 |        27054 |
    | 1.6 GB   |      50 |          25241 |        25591 |
    ------------------------------------------------------
    | 7.6 GB   |       1 |           5779 |         6224 |
    | 7.6 GB   |       2 |          10897 |        13611 | + 24.9%
    | 7.6 GB   |       4 |          32683 |        33108 |
    | 7.6 GB   |       8 |          33968 |        34712 |
    | 7.6 GB   |      16 |          32287 |        32895 |
    | 7.6 GB   |      20 |          27770 |        31689 | + 14.1%
    | 7.6 GB   |      30 |          26739 |        29003 |
    | 7.6 GB   |      40 |          24901 |        26683 |
    | 7.6 GB   |      50 |          17115 |        25925 | + 51.5%
    ------------------------------------------------------

  (Davidlohr also has one additional patch which further improves
  throughput, though I will ask him to send it directly to you as I have
  suggested some minor changes)."

* emailed patches from Michel Lespinasse <walken@google.com>:
  rwsem: no need for explicit signed longs
  x86 rwsem: avoid taking slow path when stealing write lock
  rwsem: do not block readers at head of queue if other readers are active
  rwsem: implement support for write lock stealing on the fastpath
  rwsem: simplify __rwsem_do_wake
  rwsem: skip initial trylock in rwsem_down_write_failed
  rwsem: avoid taking wait_lock in rwsem_down_write_failed
  rwsem: use cmpxchg for trying to steal write lock
  rwsem: more agressive lock stealing in rwsem_down_write_failed
  rwsem: simplify rwsem_down_write_failed
  rwsem: simplify rwsem_down_read_failed
  rwsem: move rwsem_down_failed_common code into rwsem_down_{read,write}_failed
  rwsem: shorter spinlocked section in rwsem_down_failed_common()
  rwsem: make the waiter type an enumeration rather than a bitmask
2013-05-07 09:22:03 -07:00
Davidlohr Bueso b5f541810e rwsem: no need for explicit signed longs
Change explicit "signed long" declarations into plain "long" as suggested
by Peter Hurley.

Signed-off-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Reviewed-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 07:20:17 -07:00
Michel Lespinasse 25c3932596 rwsem: do not block readers at head of queue if other readers are active
This change fixes a race condition where a reader might determine it
needs to block, but by the time it acquires the wait_lock the rwsem has
active readers and no queued waiters.

In this situation the reader can run in parallel with the existing
active readers; it does not need to block until the active readers
complete.

Thanks to Peter Hurley for noticing this possible race.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 07:20:17 -07:00
Michel Lespinasse fe6e674c61 rwsem: implement support for write lock stealing on the fastpath
When we decide to wake up readers, we must first grant them as many read
locks as necessary, and then actually wake up all these readers.  But in
order to know how many read shares to grant, we must first count the
readers at the head of the queue.  This might take a while if there are
many readers, and we want to be protected against a writer stealing the
lock while we're counting.  To that end, we grant the first reader lock
before counting how many more readers are queued.

We also require some adjustments to the wake_type semantics.

RWSEM_WAKE_NO_ACTIVE used to mean that we had found the count to be
RWSEM_WAITING_BIAS, in which case the rwsem was known to be free as
nobody could steal it while we hold the wait_lock.  This doesn't make
sense once we implement fastpath write lock stealing, so we now use
RWSEM_WAKE_ANY in that case.

Similarly, when rwsem_down_write_failed found that a read lock was
active, it would use RWSEM_WAKE_READ_OWNED which signalled that new
readers could be woken without checking first that the rwsem was
available.  We can't do that anymore since the existing readers might
release their read locks, and a writer could steal the lock before we
wake up additional readers.  So, we have to use a new RWSEM_WAKE_READERS
value to indicate we only want to wake readers, but we don't currently
hold any read lock.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 07:20:16 -07:00
Michel Lespinasse 8cf5322ce6 rwsem: simplify __rwsem_do_wake
This is mostly for cleanup value:

- We don't need several gotos to handle the case where the first
  waiter is a writer. Two simple tests will do (and generate very
  similar code).

- In the remainder of the function, we know the first waiter is a reader,
  so we don't have to double check that. We can use do..while loops
  to iterate over the readers to wake (generates slightly better code).

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 07:20:16 -07:00
Michel Lespinasse 9b0fc9c09f rwsem: skip initial trylock in rwsem_down_write_failed
We can skip the initial trylock in rwsem_down_write_failed() if there
are known active lockers already, thus saving one likely-to-fail
cmpxchg.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 07:20:16 -07:00
Michel Lespinasse a7d2c573ae rwsem: avoid taking wait_lock in rwsem_down_write_failed
In rwsem_down_write_failed(), if there are active locks after we wake up
(i.e.  the lock got stolen from us), skip taking the wait_lock and go
back to sleep immediately.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 07:20:16 -07:00
Michel Lespinasse 5ede972df1 rwsem: use cmpxchg for trying to steal write lock
Using rwsem_atomic_update to try stealing the write lock forced us to
undo the adjustment in the failure path.  We can have simpler and faster
code by using cmpxchg instead.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 07:20:16 -07:00
Michel Lespinasse ed00f64346 rwsem: more agressive lock stealing in rwsem_down_write_failed
Some small code simplifications can be achieved by doing more agressive
lock stealing:

- When rwsem_down_write_failed() notices that there are no active locks
  (and thus no thread to wake us if we decided to sleep), it used to wake
  the first queued process. However, stealing the lock is also sufficient
  to deal with this case, so we don't need this check anymore.

- In try_get_writer_sem(), we can steal the lock even when the first waiter
  is a reader. This is correct because the code path that wakes readers is
  protected by the wait_lock. As to the performance effects of this change,
  they are expected to be minimal: readers are still granted the lock
  (rather than having to acquire it themselves) when they reach the front
  of the wait queue, so we have essentially the same behavior as in
  rwsem-spinlock.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 07:20:16 -07:00
Michel Lespinasse 023fe4f712 rwsem: simplify rwsem_down_write_failed
When waking writers, we never grant them the lock - instead, they have
to acquire it themselves when they run, and remove themselves from the
wait_list when they succeed.

As a result, we can do a few simplifications in rwsem_down_write_failed():

- We don't need to check for !waiter.task since __rwsem_do_wake() doesn't
  remove writers from the wait_list

- There is no point releaseing the wait_lock before entering the wait loop,
  as we will need to reacquire it immediately. We can change the loop so
  that the lock is always held at the start of each loop iteration.

- We don't need to get a reference on the task structure, since the task
  is responsible for removing itself from the wait_list. There is no risk,
  like in the rwsem_down_read_failed() case, that a task would wake up and
  exit (thus destroying its task structure) while __rwsem_do_wake() is
  still running - wait_lock protects against that.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 07:20:16 -07:00
Michel Lespinasse da16922cc0 rwsem: simplify rwsem_down_read_failed
When trying to acquire a read lock, the RWSEM_ACTIVE_READ_BIAS
adjustment doesn't cause other readers to block, so we never have to
worry about waking them back after canceling this adjustment in
rwsem_down_read_failed().

We also never want to steal the lock in rwsem_down_read_failed(), so we
don't have to grab the wait_lock either.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 07:20:16 -07:00
Michel Lespinasse 1e78277ccb rwsem: move rwsem_down_failed_common code into rwsem_down_{read,write}_failed
Remove the rwsem_down_failed_common function and replace it with two
identical copies of its code in rwsem_down_{read,write}_failed.

This is because we want to make different optimizations in
rwsem_down_{read,write}_failed; we are adding this pure-duplication
step as a separate commit in order to make it easier to check the
following steps.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 07:20:16 -07:00
Michel Lespinasse f7dd1cee9a rwsem: shorter spinlocked section in rwsem_down_failed_common()
This change reduces the size of the spinlocked and TASK_UNINTERRUPTIBLE
sections in rwsem_down_failed_common():

- We only need the sem->wait_lock to insert ourselves on the wait_list;
  the waiter node can be prepared outside of the wait_lock.

- The task state only needs to be set to TASK_UNINTERRUPTIBLE immediately
  before checking if we actually need to sleep; it doesn't need to protect
  the entire function.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 07:20:16 -07:00
Michel Lespinasse e2d57f782c rwsem: make the waiter type an enumeration rather than a bitmask
We are not planning to add some new waiter flags, so we can convert the
waiter type into an enumeration.

Background: David Howells suggested I do this back when I tried adding
a new waiter type for unfair readers. However, I believe the cleanup
applies regardless of that use case.

Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 07:20:15 -07:00
David Howells 9e6879460c Give the OID registry file module info to avoid kernel tainting
Give the OID registry file module information so that it doesn't taint the
kernel when compiled as a module and loaded.

Reported-by: Dros Adamson <Weston.Adamson@netapp.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Trond Myklebust <Trond.Myklebust@netapp.com>
cc: stable@vger.kernel.org
cc: linux-nfs@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-05 14:38:00 -07:00
Linus Torvalds 20a2078ce7 Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux
Pull drm updates from Dave Airlie:
 "This is the main drm pull request for 3.10.

  Wierd bits:
   - OMAP drm changes required OMAP dss changes, in drivers/video, so I
     took them in here.
   - one more fbcon fix for font handover
   - VT switch avoidance in pm code
   - scatterlist helpers for gpu drivers - have acks from akpm

  Highlights:
   - qxl kms driver - driver for the spice qxl virtual GPU

  Nouveau:
   - fermi/kepler VRAM compression
   - GK110/nvf0 modesetting support.

  Tegra:
   - host1x core merged with 2D engine support

  i915:
   - vt switchless resume
   - more valleyview support
   - vblank fixes
   - modesetting pipe config rework

  radeon:
   - UVD engine support
   - SI chip tiling support
   - GPU registers initialisation from golden values.

  exynos:
   - device tree changes
   - fimc block support

  Otherwise:
   - bunches of fixes all over the place."

* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (513 commits)
  qxl: update to new idr interfaces.
  drm/nouveau: fix build with nv50->nvc0
  drm/radeon: fix handling of v6 power tables
  drm/radeon: clarify family checks in pm table parsing
  drm/radeon: consolidate UVD clock programming
  drm/radeon: fix UPLL_REF_DIV_MASK definition
  radeon: add bo tracking debugfs
  drm/radeon: add new richland pci ids
  drm/radeon: add some new SI PCI ids
  drm/radeon: fix scratch reg handling for UVD fence
  drm/radeon: allocate SA bo in the requested domain
  drm/radeon: fix possible segfault when parsing pm tables
  drm/radeon: fix endian bugs in atom_allocate_fb_scratch()
  OMAPDSS: TFP410: return EPROBE_DEFER if the i2c adapter not found
  OMAPDSS: VENC: Add error handling for venc_probe_pdata
  OMAPDSS: HDMI: Add error handling for hdmi_probe_pdata
  OMAPDSS: RFBI: Add error handling for rfbi_probe_pdata
  OMAPDSS: DSI: Add error handling for dsi_probe_pdata
  OMAPDSS: SDI: Add error handling for sdi_probe_pdata
  OMAPDSS: DPI: Add error handling for dpi_probe_pdata
  ...
2013-05-02 19:40:34 -07:00
Linus Torvalds 0279b3c0ad Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "This fixes the cputime scaling overflow problems for good without
  having bad 32-bit overhead, and gets rid of the div64_u64_rem() helper
  as well."

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "math64: New div64_u64_rem helper"
  sched: Avoid prev->stime underflow
  sched: Do not account bogus utime
  sched: Avoid cputime scaling overflow
2013-05-02 14:56:31 -07:00
Linus Torvalds 20b4fb4852 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull VFS updates from Al Viro,

Misc cleanups all over the place, mainly wrt /proc interfaces (switch
create_proc_entry to proc_create(), get rid of the deprecated
create_proc_read_entry() in favor of using proc_create_data() and
seq_file etc).

7kloc removed.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits)
  don't bother with deferred freeing of fdtables
  proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h
  proc: Make the PROC_I() and PDE() macros internal to procfs
  proc: Supply a function to remove a proc entry by PDE
  take cgroup_open() and cpuset_open() to fs/proc/base.c
  ppc: Clean up scanlog
  ppc: Clean up rtas_flash driver somewhat
  hostap: proc: Use remove_proc_subtree()
  drm: proc: Use remove_proc_subtree()
  drm: proc: Use minor->index to label things, not PDE->name
  drm: Constify drm_proc_list[]
  zoran: Don't print proc_dir_entry data in debug
  reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show()
  proc: Supply an accessor for getting the data from a PDE's parent
  airo: Use remove_proc_subtree()
  rtl8192u: Don't need to save device proc dir PDE
  rtl8187se: Use a dir under /proc/net/r8180/
  proc: Add proc_mkdir_data()
  proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h}
  proc: Move PDE_NET() to fs/proc/proc_net.c
  ...
2013-05-01 17:51:54 -07:00
Linus Torvalds 5f56886521 Merge branch 'akpm' (incoming from Andrew)
Merge third batch of fixes from Andrew Morton:
 "Most of the rest.  I still have two large patchsets against AIO and
  IPC, but they're a bit stuck behind other trees and I'm about to
  vanish for six days.

   - random fixlets
   - inotify
   - more of the MM queue
   - show_stack() cleanups
   - DMI update
   - kthread/workqueue things
   - compat cleanups
   - epoll udpates
   - binfmt updates
   - nilfs2
   - hfs
   - hfsplus
   - ptrace
   - kmod
   - coredump
   - kexec
   - rbtree
   - pids
   - pidns
   - pps
   - semaphore tweaks
   - some w1 patches
   - relay updates
   - core Kconfig changes
   - sysrq tweaks"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (109 commits)
  Documentation/sysrq: fix inconstistent help message of sysrq key
  ethernet/emac/sysrq: fix inconstistent help message of sysrq key
  sparc/sysrq: fix inconstistent help message of sysrq key
  powerpc/xmon/sysrq: fix inconstistent help message of sysrq key
  ARM/etm/sysrq: fix inconstistent help message of sysrq key
  power/sysrq: fix inconstistent help message of sysrq key
  kgdb/sysrq: fix inconstistent help message of sysrq key
  lib/decompress.c: fix initconst
  notifier-error-inject: fix module names in Kconfig
  kernel/sys.c: make prctl(PR_SET_MM) generally available
  UAPI: remove empty Kbuild files
  menuconfig: print more info for symbol without prompts
  init/Kconfig: re-order CONFIG_EXPERT options to fix menuconfig display
  kconfig menu: move Virtualization drivers near other virtualization options
  Kconfig: consolidate CONFIG_DEBUG_STRICT_USER_COPY_CHECKS
  relay: use macro PAGE_ALIGN instead of FIX_SIZE
  kernel/relay.c: move FIX_SIZE macro into relay.c
  kernel/relay.c: remove unused function argument actor
  drivers/w1/slaves/w1_ds2760.c: fix the error handling in w1_ds2760_add_slave()
  drivers/w1/slaves/w1_ds2781.c: fix the error handling in w1_ds2781_add_slave()
  ...
2013-04-30 17:37:43 -07:00