linux-toradex.git/arch/Kconfig, branch v2.6.32.9

oprofile: fix oprofile regression: select RING_BUFFER_ALLOW_SWAP

2009-09-17T19:53:42+00:00

commit 85bac32c4a52c592b857f2c360cc5ec93a097d70
    ring-buffer: only enable ring_buffer_swap_cpu when needed
broke oprofile (at least on s390, but likely on all platforms).

this patch lets oprofile select RING_BUFER_ALLOW_SWAP to make
ring_buffer_swap_cpu usable for oprofile.

Signed-off-by: Christian Borntraeger 
LKML-Reference: <200909162156.49239.borntraeger@de.ibm.com>
Cc: Ingo Molnar 
Cc: Robert Richter 
Signed-off-by: Steven Rostedt

oprofile: Implement performance counter multiplexing

2009-07-20T14:33:53+00:00

The number of hardware counters is limited. The multiplexing feature
enables OProfile to gather more events than counters are provided by
the hardware. This is realized by switching between events at an user
specified time interval.

A new file (/dev/oprofile/time_slice) is added for the user to specify
the timer interval in ms. If the number of events to profile is higher
than the number of hardware counters available, the patch will
schedule a work queue that switches the event counter and re-writes
the different sets of values into it. The switching mechanism needs to
be implemented for each architecture to support multiplexing. This
patch only implements AMD CPU support, but multiplexing can be easily
extended for other models and architectures.

There are follow-on patches that rework parts of this patch.

Signed-off-by: Jason Yeh 
Signed-off-by: Robert Richter

gcov: add gcov profiling infrastructure

2009-06-18T20:03:57+00:00

Enable the use of GCC's coverage testing tool gcov [1] with the Linux
kernel.  gcov may be useful for:

 * debugging (has this code been reached at all?)
 * test improvement (how do I change my test to cover these lines?)
 * minimizing kernel configurations (do I need this option if the
   associated code is never run?)

The profiling patch incorporates the following changes:

 * change kbuild to include profiling flags
 * provide functions needed by profiling code
 * present profiling data as files in debugfs

Note that on some architectures, enabling gcc's profiling option
"-fprofile-arcs" for the entire kernel may trigger compile/link/
run-time problems, some of which are caused by toolchain bugs and
others which require adjustment of architecture code.

For this reason profiling the entire kernel is initially restricted
to those architectures for which it is known to work without changes.
This restriction can be lifted once an architecture has been tested
and found compatible with gcc's profiling. Profiling of single files
or directories is still available on all platforms (see config help
text).

[1] http://gcc.gnu.org/onlinedocs/gcc/Gcov.html

Signed-off-by: Peter Oberparleiter 
Cc: Andi Kleen 
Cc: Huang Ying 
Cc: Li Wei 
Cc: Michael Ellerman 
Cc: Ingo Molnar 
Cc: Heiko Carstens 
Cc: Martin Schwidefsky 
Cc: Rusty Russell 
Cc: WANG Cong 
Cc: Sam Ravnborg 
Cc: Jeff Dike 
Cc: Al Viro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mutex: have non-spinning mutexes on s390 by default

2009-04-09T17:28:24+00:00

Impact: performance regression fix for s390

The adaptive spinning mutexes will not always do what one would expect on
virtualized architectures like s390. Especially the cpu_relax() loop in
mutex_spin_on_owner might hurt if the mutex holding cpu has been scheduled
away by the hypervisor.

We would end up in a cpu_relax() loop when there is no chance that the
state of the mutex changes until the target cpu has been scheduled again by
the hypervisor.

For that reason we should change the default behaviour to no-spin on s390.

We do have an instruction which allows to yield the current cpu in favour of
a different target cpu. Also we have an instruction which allows us to figure
out if the target cpu is physically backed.

However we need to do some performance tests until we can come up with
a solution that will do the right thing on s390.

Signed-off-by: Heiko Carstens 
Acked-by: Peter Zijlstra 
Cc: Martin Schwidefsky 
Cc: Christian Borntraeger 
LKML-Reference: <20090409184834.7a0df7b2@osiris.boeblingen.de.ibm.com>
Signed-off-by: Ingo Molnar

Merge branch 'tracing/core-v2' into tracing-for-linus

2009-04-01T22:49:02+00:00

Conflicts:
	include/linux/slub_def.h
	lib/Kconfig.debug
	mm/slob.c
	mm/slub.c

tracing: clean up menu

2009-03-05T20:53:25+00:00

Clean up menu structure, introduce TRACING_SUPPORT switch that signals
whether an architecture supports various instrumentation mechanisms.

Signed-off-by: Ingo Molnar

dma-debug: add Kconfig entry

2009-03-05T13:36:50+00:00

Impact: add a Kconfig entry for DMA-API debugging

Signed-off-by: Joerg Roedel

[CVE-2009-0029] System call wrapper infrastructure

2009-01-14T13:15:16+00:00

From: Martin Schwidefsky 

By selecting HAVE_SYSCALL_WRAPPERS architectures can activate
system call wrappers in order to sign extend system call arguments.

All architectures where the ABI defines that the caller of a function
has to perform sign extension probably need this.

Reported-by: Christian Borntraeger 
Acked-by: Ralf Baechle 
Signed-off-by: Martin Schwidefsky 
Signed-off-by: Heiko Carstens

oprofile: select RING_BUFFER

2008-12-12T08:46:31+00:00

Impact: build fix

OProfile now depends on the ring buffer infrastructure:

 arch/x86/oprofile/built-in.o: In function `oprofile_add_ibs_sample':
 : undefined reference to `ring_buffer_unlock_commit'

Select TRACING and RING_BUFFER when oprofile is enabled.

Signed-off-by: Ingo Molnar

remove __ARCH_WANT_COMPAT_SYS_PTRACE

2008-11-30T19:00:15+00:00

All architectures now use the generic compat_sys_ptrace, as should every
new architecture that needs 32bit compat (if we'll ever get another).

Remove the now superflous __ARCH_WANT_COMPAT_SYS_PTRACE define, and also
kill a comment about __ARCH_SYS_PTRACE that was added after
__ARCH_SYS_PTRACE was already gone.

Signed-off-by: Christoph Hellwig 
Acked-by: David S. Miller 
Signed-off-by: Linus Torvalds