linux-toradex.git/lib, branch v3.10.2

lib/mpi/mpicoder.c: looping issue, need stop when equal to zero, found by 'EXTRA_FLAGS=-W'.

2013-06-12T23:29:44+00:00

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 
Cc: Rusty Russell 
Cc: David Howells 
Cc: James Morris 
Cc: Andy Shevchenko 
Acked-by: David Howells 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

MPILIB: disable usage of floating point registers on parisc

2013-05-24T20:30:11+00:00

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

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

2013-05-23T16:27:08+00:00

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

lib: make iovec obj instead of lib

2013-05-23T16:17:11+00:00

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 
Acked-by: Rusty Russell 
Signed-off-by: Linus Torvalds

klist: del waiter from klist_remove_waiters before wakeup waitting process

2013-05-21T17:16:39+00:00

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 
Acked-by: Peter Zijlstra 
Signed-off-by: Greg Kroah-Hartman

Hoist memcpy_fromiovec/memcpy_toiovec into lib/

2013-05-20T00:54:22+00:00

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 6d4f0139d642c45411a47879325891ce2a7c164a 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 
Acked-by: David S. Miller 
Acked-by: Michael S. Tsirkin 
Signed-off-by: Rusty Russell

Merge branch 'for-3.10/drivers' of git://git.kernel.dk/linux-block

2013-05-08T18:51:05+00:00

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 
  ...

rwsem: check counter to avoid cmpxchg calls

2013-05-07T23:11:51+00:00

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 
Signed-off-by: Linus Torvalds

kref: minor cleanup

2013-05-07T23:09:00+00:00

 - 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 
[ Removed line-break, changed to use WARN_ON_ONCE()  - Linus ]
Signed-off-by: Linus Torvalds

Merge branch 'rwsem-optimizations'

2013-05-07T16:22:03+00:00

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 :
  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