Impact: clean, reduce kernel size a bit, avoid sparse warnings

Fixes sparse warnings:

 arch/x86/kernel/cpu/perf_counter.c:153:6: warning: symbol 'hw_perf_enable_all' was not declared. Should it be static?
 arch/x86/kernel/cpu/perf_counter.c:279:3: warning: returning void-valued expression
 arch/x86/kernel/cpu/perf_counter.c:206:3: warning: returning void-valued expression
 arch/x86/kernel/cpu/perf_counter.c:206:3: warning: returning void-valued expression
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: fix panic possible panic

Some versions of GCC inline the weak global function if it's empty.
Add a barrier() to work it around.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: build fix on ia64

KOSAKI Motohiro reported that -tip doesnt build on ia64 because
asm/perf_counter.h only exists on x86 for now. Fix it.
Reported-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Tested-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: extend performance counter support on x86 Intel CPUs

Modern Intel CPUs have 3 "fixed-function" performance counters, which
count these hardware events:

    Instr_Retired.Any
    CPU_CLK_Unhalted.Core
    CPU_CLK_Unhalted.Ref

Add support for them to the performance counters subsystem.

Their use is transparent to user-space: the counter scheduler is
extended to automatically recognize the cases where a fixed-function
PMC can be utilized instead of a generic PMC. In such cases the
generic PMC is kept available for more counters.

The above fixed-function events map to these generic counter hw events:

        PERF_COUNT_INSTRUCTIONS
        PERF_COUNT_CPU_CYCLES
        PERF_COUNT_BUS_CYCLES

(The 'bus' cycles are in reality often CPU-ish cycles, just with a fixed
 frequency.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Generalize "bus cycles" hw events - and map them to CPU_CLK_Unhalted.Ref
on x86. (which is a good enough approximation)
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: clean up and refactor code

refactor the counter scheduler: separate out in/out functions and
introduce a counter-rotation function as well.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: remove dead code

nr_inherited was not maintained correctly (not decremented) - and also
not used - remove it.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: extend debug printouts
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Allow lowlevel ->enable() op to return an error if a counter can not be
added. This can be used to handle counter constraints.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Signed-off-by: Ingo Molnar <mingo@elte.hu>

Change counter inheritance from a 'push' to a 'pull' model: instead of
child tasks pushing their final counts to the parent, reuse the wait4
infrastructure to pull counters as child tasks are exit-processed,
much like how cutime/cstime is collected.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: fix per task clock counter precision
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: rename field names

Shorten them.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: clean up
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Enumerate fixed-mode PMCs based on CPUID, and feed that into the
perfcounter code.

Does not use fixed-mode PMCs yet.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: refactor the x86 code for fixed-mode PMCs

Extend the data structures and rename the existing facilities
to allow for a 'generic' versus 'fixed' counter distinction.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: rename include file

We'll be providing an asm/perf_counter.h to the generic perfcounter code,
so use the already existing x86 file for this purpose and rename it.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: schedule in groups atomically

If there are multiple groups in a task, make sure they are scheduled
in and out atomically.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: remove debug checks
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: cleanup, avoid sparse warnings, reduce kernel size a bit

Fixes these sparse warnings:
 arch/x86/kernel/cpu/perf_counter.c:44:11: warning: symbol 'intel_perfmon_event_map' was not declared. Should it be static?
 arch/x86/kernel/cpu/perf_counter.c:54:11: warning: symbol 'max_intel_perfmon_events' was not declared. Should it be static?
Signed-off-by: Jaswinder Singh <jaswinder@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: implement default-off counters

Make sure that counters that are created with counter.hw_event.disabled=1,
get created in disabled state.

They can be enabled via:

        prctl(PR_TASK_PERF_COUNTERS_ENABLE);
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Pavel Machek pointed out that performance counters should be flushed
when crossing protection domains on setuid execution.
Reported-by: Pavel Machek <pavel@suse.cz>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

If counters are exiting via do_exit() not via filp close, then
the CPU context needs to be released - otherwise future percpu
counter creations might fail.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Fix non-working NMI sampling in certain bootup scenarios.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Make perf_max_counters default to at least 1 - this allows the sw
counters to be used.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Do not write MSR_CORE_PERF_GLOBAL_CTRL on CPUs where it does not exist.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: add new feature, new sw counter

Add a counter that counts the number of pagefaults a task
is experiencing.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: add new feature, new sw counter

Add a counter that counts the number of cross-CPU migrations a
task is suffering.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: add new feature, new sw counter

Add a counter that counts the number of context-switches a task
is doing.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: bugfix

Update the task clock counter to the new math.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: implement new performance feature

Counter inheritance can be used to run performance counters in a workload,
transparently - and pipe back the counter results to the parent counter.

Inheritance for performance counters works the following way: when creating
a counter it can be marked with the .inherit=1 flag. Such counters are then
'inherited' by all child tasks (be they fork()-ed or clone()-ed). These
counters get inherited through exec() boundaries as well (except through
setuid boundaries).

The counter values get added back to the parent counter(s) when the child
task(s) exit - much like stime/utime statistics are gathered. So inherited
counters are ideal to gather summary statistics about an application's
behavior via shell commands, without having to modify that application.

The timec.c command utilizes counter inheritance:

  http://redhat.com/~mingo/perfcounters/timec.c

Sample output:

   $ ./timec -e 1 -e 3 -e 5 ls -lR /usr/include/ >/dev/null

   Performance counter stats for 'ls':

           163516953 instructions
                2295 cache-misses
             2855182 branch-misses
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: restructure code

Change counter math from absolute values to clear delta logic.

We try to extract elapsed deltas from the raw hw counter - and put
that into the generic counter.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: new API

Implement the atomic64_t APIs on 32-bit as well. Will be used by
the performance counters code.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/jwboyer/powerpc-4xx:
  powerpc/40x: Add proper BOOTCFLAGS for cuboot-acadia

* 'i2c-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6:
  i2c-highlander: Trivial endian casting fixes
  i2c-pmcmsp: Fix endianness misannotation

* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  Commands needing to be retried require a complete re-initialization.

* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
  MIPS: IP32: Update defconfig
  MIPS: Add missing calls to plat_unmap_dma_mem.
  MIPS: Kconfig: Fix the arch-specific header path
  MIPS: Use EI/DI for MIPS R2.

For the console, there is a 1:1 mapping of glyphs which cannot be found
in the current font.  This seems to be meant as a kind of 'emergency
fallback' for fonts without unicode mapping which otherwise would
display nothing readable on the screen.

At the moment it affects all chars for which no substitution character
is defined.  In particular this means that for all chars (>= 128) where
there is no iso88591-1/unicode character (e.g.  control character area)
you'll get the very strange 1:1 mapping of the (cp437) graphics card
glyphs.

I'm pretty sure that the 1:1 mapping should only affect strict ASCII
code characters, i.e.  chars < 128.

The patch limits the mapping as it probably was meant anyway.
Signed-off-by: Ingo Brueckl <ib@wupperonline.de>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Egmont Koblinger <egmont@uhulinux.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

There is a major bug in the cp437 to unicode translation table.  Char
0x7c is mapped to U+00a5 which is the Yen sign and wrong.  The right
mapping is U+00a6 (broken bar).

Furthermore, a mapping for U+00b4 (a widely used character) is missing
even though easily possible.

The patch fixes these, as well as it provides a few other useful
mappings.

The changes are as follows:

  0x0f (enhancement) enables a sort of currency symbol
  0x27 (bug) enables a sort of acute accent which is a widely used character
  0x44 (enhancement) enables a sort of icelandic capital letter eth
  0x7c (major bug) corrects mapping
  0xeb (enhancement) enables a sort of icelandic small letter eth
  0xee (enhancement) enables a sort of math 'element of'
Signed-off-by: Ingo Brueckl <ib@wupperonline.de>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>