linux.git/lib, branch v3.3-rc5

Reduce the number of expensive division instructions done by _parse_integer()

2012-02-09T18:09:30+00:00

_parse_integer() does one or two division instructions (which are slow)
per digit parsed to perform the overflow check.

Furthermore, these are particularly expensive examples of division
instruction as the number of clock cycles required to complete them may
go up with the position of the most significant set bit in the dividend:

	if (*res > div_u64(ULLONG_MAX - val, base))

which is as maximal as possible.

Worse, on 32-bit arches, more than one of these division instructions
may be required per digit.

So, assuming we don't support a base of more than 16, skip the check if the
top nibble of the result is not set at this point.

Signed-off-by: David Howells 
[ Changed it to not dereference the pointer all the time - even if the
  compiler can and does optimize it away, the code just looks cleaner.
  And edited the top nybble test slightly to make the code generated on
  x86-64 better in the loop - test against a hoisted constant instead of
  shifting and testing the result ]
Signed-off-by: Linus Torvalds

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

2012-02-07T22:32:24+00:00

arch: fix ioport mapping on mips,sh

Kevin Cernekee reported that recent cleanup that replaced pci_iomap with
a generic function failed to take into account the differences in io
port handling on mips and sh architectures.

Rather than revert the changes reintroducing the code duplication, this
patchset fixes this by adding ability for architectures to override
ioport mapping for pci devices.

Signed-off-by: Michael S. Tsirkin 

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  sh: use the the PCI channels's io_map_base
  mips: use the the PCI controller's io_map_base
  lib: add NO_GENERIC_PCI_IOPORT_MAP

Merge branches 'core-urgent-for-linus', 'perf-urgent-for-linus', 'sched-urgent-for-linus' and 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2012-02-02T19:11:13+00:00

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  bugs, x86: Fix printk levels for panic, softlockups and stack dumps

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf top: Fix number of samples displayed
  perf tools: Fix strlen() bug in perf_event__synthesize_event_type()
  perf tools: Fix broken build by defining _GNU_SOURCE in Makefile
  x86/dumpstack: Remove unneeded check in dump_trace()
  perf: Fix broken interrupt rate throttling

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/rt: Fix task stack corruption under __ARCH_WANT_INTERRUPTS_ON_CTXSW
  sched: Fix ancient race in do_exit()
  sched/nohz: Fix nohz cpu idle load balancing state with cpu hotplug
  sched/s390: Fix compile error in sched/core.c
  sched: Fix rq->nr_uninterruptible update race

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/reboot: Remove VersaLogic Menlow reboot quirk
  x86/reboot: Skip DMI checks if reboot set by user
  x86: Properly parenthesize cmpxchg() macro arguments

lib: Fix 32-bit sparc udiv_qrnnd() definition in mpilib's longlong.h

2012-02-01T23:34:25+00:00

This copy of longlong.h is extremely dated and results in compile
errors on sparc32 when MPILIB is enabled, copy over the more uptodate
implementation from arch/sparc/math/sfp-util_32.h

Reported-by: Al Viro 
Signed-off-by: David S. Miller 
Signed-off-by: James Morris

lib: Fix multiple definitions of clz_tab

2012-02-01T23:34:23+00:00

Both sparc 32-bit's software divide assembler and MPILIB provide
clz_tab[] with identical contents.

Break it out into a seperate object file and select it when
SPARC32 or MPILIB is set.

Reported-by: Al Viro 
Signed-off-by: David S. Miller 
Signed-off-by: James Morris

lib/digsig: checks for NULL return value

2012-02-01T13:24:04+00:00

mpi_read_from_buffer() return value must not be NULL.

Signed-off-by: Dmitry Kasatkin 
Reviewed-by: Tetsuo Handa 
Signed-off-by: James Morris

lib/mpi: added missing NULL check

2012-02-01T13:23:39+00:00

Added missing NULL check after mpi_alloc_limb_space().

Signed-off-by: Dmitry Kasatkin 
Reviewed-by: Tetsuo Handa 
Signed-off-by: James Morris

lib/mpi: added comment on divide by 0 case

2012-02-01T13:23:39+00:00

Comment explains that existing clients do not call this function
with dsize == 0, which means that 1/0 should not happen.

Signed-off-by: Dmitry Kasatkin 
Reviewed-by: Tetsuo Handa 
Signed-off-by: James Morris

lib/mpi: check for possible zero length

2012-02-01T13:23:39+00:00

Buggy client might pass zero nlimbs which is meaningless.
Added check for zero length.

Signed-off-by: Dmitry Kasatkin 
Reviewed-by: Tetsuo Handa 
Signed-off-by: James Morris

lib/digsig: pkcs_1_v1_5_decode_emsa cleanup

2012-02-01T13:23:39+00:00

Removed useless 'is_valid' variable in pkcs_1_v1_5_decode_emsa(),
which was inhereted from original code. Client now uses return value
to check for an error.

Signed-off-by: Dmitry Kasatkin 
Reviewed-by: Tetsuo Handa 
Signed-off-by: James Morris