Commit Graph

351 Commits

Author SHA1 Message Date
David Howells 8feae13110 NOMMU: Make VMAs per MM as for MMU-mode linux
Make VMAs per mm_struct as for MMU-mode linux.  This solves two problems:

 (1) In SYSV SHM where nattch for a segment does not reflect the number of
     shmat's (and forks) done.

 (2) In mmap() where the VMA's vm_mm is set to point to the parent mm by an
     exec'ing process when VM_EXECUTABLE is specified, regardless of the fact
     that a VMA might be shared and already have its vm_mm assigned to another
     process or a dead process.

A new struct (vm_region) is introduced to track a mapped region and to remember
the circumstances under which it may be shared and the vm_list_struct structure
is discarded as it's no longer required.

This patch makes the following additional changes:

 (1) Regions are now allocated with alloc_pages() rather than kmalloc() and
     with no recourse to __GFP_COMP, so the pages are not composite.  Instead,
     each page has a reference on it held by the region.  Anything else that is
     interested in such a page will have to get a reference on it to retain it.
     When the pages are released due to unmapping, each page is passed to
     put_page() and will be freed when the page usage count reaches zero.

 (2) Excess pages are trimmed after an allocation as the allocation must be
     made as a power-of-2 quantity of pages.

 (3) VMAs are added to the parent MM's R/B tree and mmap lists.  As an MM may
     end up with overlapping VMAs within the tree, the VMA struct address is
     appended to the sort key.

 (4) Non-anonymous VMAs are now added to the backing inode's prio list.

 (5) Holes may be punched in anonymous VMAs with munmap(), releasing parts of
     the backing region.  The VMA and region structs will be split if
     necessary.

 (6) sys_shmdt() only releases one attachment to a SYSV IPC shared memory
     segment instead of all the attachments at that addresss.  Multiple
     shmat()'s return the same address under NOMMU-mode instead of different
     virtual addresses as under MMU-mode.

 (7) Core dumping for ELF-FDPIC requires fewer exceptions for NOMMU-mode.

 (8) /proc/maps is now the global list of mapped regions, and may list bits
     that aren't actually mapped anywhere.

 (9) /proc/meminfo gains a line (tagged "MmapCopy") that indicates the amount
     of RAM currently allocated by mmap to hold mappable regions that can't be
     mapped directly.  These are copies of the backing device or file if not
     anonymous.

These changes make NOMMU mode more similar to MMU mode.  The downside is that
NOMMU mode requires some extra memory to track things over NOMMU without this
patch (VMAs are no longer shared, and there are now region structs).

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Mike Frysinger <vapier.adi@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
2009-01-08 12:04:47 +00:00
Ingo Molnar da4276b829 x86: offer frame pointers in all build modes
CONFIG_FRAME_POINTERS=y results in much better debug info for the
kernel (clear and precise backtraces), with the only drawback being
a ~1% increase in kernel size.

So offer it unconditionally and enable it by default.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-07 11:18:59 +01:00
Linus Torvalds db5e53fbf0 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6:
  slub: avoid leaking caches or refcounts on sysfs error
  slab: Fix comment on #endif
  slab: remove GFP_THISNODE clearing from alloc_slabmgmt()
  slub: Add might_sleep_if() to slab_alloc()
  SLUB: failslab support
  slub: Fix incorrect use of loose
  slab: Update the kmem_cache_create documentation regarding the name parameter
  slub: make early_kmem_cache_node_alloc void
  slab: unsigned slabp->inuse cannot be less than 0
  slub - fix get_object_page comment
  SLUB: Replace __builtin_return_address(0) with _RET_IP_.
  SLUB: cleanup - define macros instead of hardcoded numbers
2008-12-30 17:28:09 -08:00
Akinobu Mita 773ff60e84 SLUB: failslab support
Currently fault-injection capability for SLAB allocator is only
available to SLAB. This patch makes it available to SLUB, too.

[penberg@cs.helsinki.fi: unify slab and slub implementations]
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
2008-12-29 11:27:46 +02:00
Ingo Molnar 6638101c11 Merge branches 'core/debugobjects', 'core/iommu', 'core/locking', 'core/printk', 'core/rcu', 'core/resources', 'core/softirq' and 'core/stacktrace' into core/core 2008-12-25 14:06:29 +01:00
Paul E. McKenney 64db4cfff9 "Tree RCU": scalable classic RCU implementation
This patch fixes a long-standing performance bug in classic RCU that
results in massive internal-to-RCU lock contention on systems with
more than a few hundred CPUs.  Although this patch creates a separate
flavor of RCU for ease of review and patch maintenance, it is intended
to replace classic RCU.

This patch still handles stress better than does mainline, so I am still
calling it ready for inclusion.  This patch is against the -tip tree.
Nevertheless, experience on an actual 1000+ CPU machine would still be
most welcome.

Most of the changes noted below were found while creating an rcutiny
(which should permit ejecting the current rcuclassic) and while doing
detailed line-by-line documentation.

Updates from v9 (http://lkml.org/lkml/2008/12/2/334):

o	Fixes from remainder of line-by-line code walkthrough,
	including comment spelling, initialization, undesirable
	narrowing due to type conversion, removing redundant memory
	barriers, removing redundant local-variable initialization,
	and removing redundant local variables.

	I do not believe that any of these fixes address the CPU-hotplug
	issues that Andi Kleen was seeing, but please do give it a whirl
	in case the machine is smarter than I am.

	A writeup from the walkthrough may be found at the following
	URL, in case you are suffering from terminal insomnia or
	masochism:

	http://www.kernel.org/pub/linux/kernel/people/paulmck/tmp/rcutree-walkthrough.2008.12.16a.pdf

o	Made rcutree tracing use seq_file, as suggested some time
	ago by Lai Jiangshan.

o	Added a .csv variant of the rcudata debugfs trace file, to allow
	people having thousands of CPUs to drop the data into
	a spreadsheet.	Tested with oocalc and gnumeric.  Updated
	documentation to suit.

Updates from v8 (http://lkml.org/lkml/2008/11/15/139):

o	Fix a theoretical race between grace-period initialization and
	force_quiescent_state() that could occur if more than three
	jiffies were required to carry out the grace-period
	initialization.  Which it might, if you had enough CPUs.

o	Apply Ingo's printk-standardization patch.

o	Substitute local variables for repeated accesses to global
	variables.

o	Fix comment misspellings and redundant (but harmless) increments
	of ->n_rcu_pending (this latter after having explicitly added it).

o	Apply checkpatch fixes.

Updates from v7 (http://lkml.org/lkml/2008/10/10/291):

o	Fixed a number of problems noted by Gautham Shenoy, including
	the cpu-stall-detection bug that he was having difficulty
	convincing me was real.  ;-)

o	Changed cpu-stall detection to wait for ten seconds rather than
	three in order to reduce false positive, as suggested by Ingo
	Molnar.

o	Produced a design document (http://lwn.net/Articles/305782/).
	The act of writing this document uncovered a number of both
	theoretical and "here and now" bugs as noted below.

o	Fix dynticks_nesting accounting confusion, simplify WARN_ON()
	condition, fix kerneldoc comments, and add memory barriers
	in dynticks interface functions.

o	Add more data to tracing.

o	Remove unused "rcu_barrier" field from rcu_data structure.

o	Count calls to rcu_pending() from scheduling-clock interrupt
	to use as a surrogate timebase should jiffies stop counting.

o	Fix a theoretical race between force_quiescent_state() and
	grace-period initialization.  Yes, initialization does have to
	go on for some jiffies for this race to occur, but given enough
	CPUs...

Updates from v6 (http://lkml.org/lkml/2008/9/23/448):

o	Fix a number of checkpatch.pl complaints.

o	Apply review comments from Ingo Molnar and Lai Jiangshan
	on the stall-detection code.

o	Fix several bugs in !CONFIG_SMP builds.

o	Fix a misspelled config-parameter name so that RCU now announces
	at boot time if stall detection is configured.

o	Run tests on numerous combinations of configurations parameters,
	which after the fixes above, now build and run correctly.

Updates from v5 (http://lkml.org/lkml/2008/9/15/92, bad subject line):

o	Fix a compiler error in the !CONFIG_FANOUT_EXACT case (blew a
	changeset some time ago, and finally got around to retesting
	this option).

o	Fix some tracing bugs in rcupreempt that caused incorrect
	totals to be printed.

o	I now test with a more brutal random-selection online/offline
	script (attached).  Probably more brutal than it needs to be
	on the people reading it as well, but so it goes.

o	A number of optimizations and usability improvements:

	o	Make rcu_pending() ignore the grace-period timeout when
		there is no grace period in progress.

	o	Make force_quiescent_state() avoid going for a global
		lock in the case where there is no grace period in
		progress.

	o	Rearrange struct fields to improve struct layout.

	o	Make call_rcu() initiate a grace period if RCU was
		idle, rather than waiting for the next scheduling
		clock interrupt.

	o	Invoke rcu_irq_enter() and rcu_irq_exit() only when
		idle, as suggested by Andi Kleen.  I still don't
		completely trust this change, and might back it out.

	o	Make CONFIG_RCU_TRACE be the single config variable
		manipulated for all forms of RCU, instead of the prior
		confusion.

	o	Document tracing files and formats for both rcupreempt
		and rcutree.

Updates from v4 for those missing v5 given its bad subject line:

o	Separated dynticks interface so that NMIs and irqs call separate
	functions, greatly simplifying it.  In particular, this code
	no longer requires a proof of correctness.  ;-)

o	Separated dynticks state out into its own per-CPU structure,
	avoiding the duplicated accounting.

o	The case where a dynticks-idle CPU runs an irq handler that
	invokes call_rcu() is now correctly handled, forcing that CPU
	out of dynticks-idle mode.

o	Review comments have been applied (thank you all!!!).
	For but one example, fixed the dynticks-ordering issue that
	Manfred pointed out, saving me much debugging.  ;-)

o	Adjusted rcuclassic and rcupreempt to handle dynticks changes.

Attached is an updated patch to Classic RCU that applies a hierarchy,
greatly reducing the contention on the top-level lock for large machines.
This passes 10-hour concurrent rcutorture and online-offline testing on
128-CPU ppc64 without dynticks enabled, and exposes some timekeeping
bugs in presence of dynticks (exciting working on a system where
"sleep 1" hangs until interrupted...), which were fixed in the
2.6.27 kernel.  It is getting more reliable than mainline by some
measures, so the next version will be against -tip for inclusion.
See also Manfred Spraul's recent patches (or his earlier work from
2004 at http://marc.info/?l=linux-kernel&m=108546384711797&w=2).
We will converge onto a common patch in the fullness of time, but are
currently exploring different regions of the design space.  That said,
I have already gratefully stolen quite a few of Manfred's ideas.

This patch provides CONFIG_RCU_FANOUT, which controls the bushiness
of the RCU hierarchy.  Defaults to 32 on 32-bit machines and 64 on
64-bit machines.  If CONFIG_NR_CPUS is less than CONFIG_RCU_FANOUT,
there is no hierarchy.  By default, the RCU initialization code will
adjust CONFIG_RCU_FANOUT to balance the hierarchy, so strongly NUMA
architectures may choose to set CONFIG_RCU_FANOUT_EXACT to disable
this balancing, allowing the hierarchy to be exactly aligned to the
underlying hardware.  Up to two levels of hierarchy are permitted
(in addition to the root node), allowing up to 16,384 CPUs on 32-bit
systems and up to 262,144 CPUs on 64-bit systems.  I just know that I
am going to regret saying this, but this seems more than sufficient
for the foreseeable future.  (Some architectures might wish to set
CONFIG_RCU_FANOUT=4, which would limit such architectures to 64 CPUs.
If this becomes a real problem, additional levels can be added, but I
doubt that it will make a significant difference on real hardware.)

In the common case, a given CPU will manipulate its private rcu_data
structure and the rcu_node structure that it shares with its immediate
neighbors.  This can reduce both lock and memory contention by multiple
orders of magnitude, which should eliminate the need for the strange
manipulations that are reported to be required when running Linux on
very large systems.

Some shortcomings:

o	More bugs will probably surface as a result of an ongoing
	line-by-line code inspection.

	Patches will be provided as required.

o	There are probably hangs, rcutorture failures, &c.  Seems
	quite stable on a 128-CPU machine, but that is kind of small
	compared to 4096 CPUs.  However, seems to do better than
	mainline.

	Patches will be provided as required.

o	The memory footprint of this version is several KB larger
	than rcuclassic.

	A separate UP-only rcutiny patch will be provided, which will
	reduce the memory footprint significantly, even compared
	to the old rcuclassic.  One such patch passes light testing,
	and has a memory footprint smaller even than rcuclassic.
	Initial reaction from various embedded guys was "it is not
	worth it", so am putting it aside.

Credits:

o	Manfred Spraul for ideas, review comments, and bugs spotted,
	as well as some good friendly competition.  ;-)

o	Josh Triplett, Ingo Molnar, Peter Zijlstra, Mathieu Desnoyers,
	Lai Jiangshan, Andi Kleen, Andy Whitcroft, and Andrew Morton
	for reviews and comments.

o	Thomas Gleixner for much-needed help with some timer issues
	(see patches below).

o	Jon M. Tollefson, Tim Pepper, Andrew Theurer, Jose R. Santos,
	Andy Whitcroft, Darrick Wong, Nishanth Aravamudan, Anton
	Blanchard, Dave Kleikamp, and Nathan Lynch for keeping machines
	alive despite my heavy abuse^Wtesting.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-18 21:56:04 +01:00
Ingo Molnar 3ae7020543 debugobjects: add boot parameter default value
Impact: add .config driven boot parameter default value

Right now debugobjects can only be activated if the debug_objects
boot parameter is passed in via the boot command line.

Make this more convenient (and randomizable) by also providing
a .config method. Enable it by default. (DEBUG_OBJECTS itself
is default-off)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-26 10:07:06 +01:00
Ingo Molnar b19b3c74c7 Merge branches 'core/debug', 'core/futexes', 'core/locking', 'core/rcu', 'core/signal', 'core/urgent' and 'core/xen' into core/core 2008-11-24 17:44:55 +01:00
Tejun Heo 0e11e342ba block: add BIG FAT WARNING to CONFIG_DEBUG_BLOCK_EXT_DEVT
CONFIG_DEBUG_BLOCK_EXT_DEVT can break booting even on some modern
distros.  Add BIG FAT WARNING to keep people at a safe distance.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-17 08:46:56 +02:00
Jason Baron 346e15beb5 driver core: basic infrastructure for per-module dynamic debug messages
Base infrastructure to enable per-module debug messages.

I've introduced CONFIG_DYNAMIC_PRINTK_DEBUG, which when enabled centralizes
control of debugging statements on a per-module basis in one /proc file,
currently, <debugfs>/dynamic_printk/modules. When, CONFIG_DYNAMIC_PRINTK_DEBUG,
is not set, debugging statements can still be enabled as before, often by
defining 'DEBUG' for the proper compilation unit. Thus, this patch set has no
affect when CONFIG_DYNAMIC_PRINTK_DEBUG is not set.

The infrastructure currently ties into all pr_debug() and dev_dbg() calls. That
is, if CONFIG_DYNAMIC_PRINTK_DEBUG is set, all pr_debug() and dev_dbg() calls
can be dynamically enabled/disabled on a per-module basis.

Future plans include extending this functionality to subsystems, that define 
their own debug levels and flags.

Usage:

Dynamic debugging is controlled by the debugfs file, 
<debugfs>/dynamic_printk/modules. This file contains a list of the modules that
can be enabled. The format of the file is as follows:

	<module_name> <enabled=0/1>
		.
		.
		.

	<module_name> : Name of the module in which the debug call resides
	<enabled=0/1> : whether the messages are enabled or not

For example:

	snd_hda_intel enabled=0
	fixup enabled=1
	driver enabled=0

Enable a module:

	$echo "set enabled=1 <module_name>" > dynamic_printk/modules

Disable a module:

	$echo "set enabled=0 <module_name>" > dynamic_printk/modules

Enable all modules:

	$echo "set enabled=1 all" > dynamic_printk/modules

Disable all modules:

	$echo "set enabled=0 all" > dynamic_printk/modules

Finally, passing "dynamic_printk" at the command line enables
debugging for all modules. This mode can be turned off via the above
disable command.

[gkh: minor cleanups and tweaks to make the build work quietly]

Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-16 09:24:47 -07:00
Ingo Molnar 8daf14cf56 Merge branches 'x86/xen', 'x86/build', 'x86/microcode', 'x86/mm-debug-v2', 'x86/memory-corruption-check', 'x86/early-printk', 'x86/xsave', 'x86/ptrace-v2', 'x86/quirks', 'x86/setup', 'x86/spinlocks' and 'x86/signal' into x86/core-v2 2008-10-12 15:50:02 +02:00
Linus Torvalds b922df7383 Merge branch 'rcu-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'rcu-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (21 commits)
  rcu: RCU-based detection of stalled CPUs for Classic RCU, fix
  rcu: RCU-based detection of stalled CPUs for Classic RCU
  rcu: add rcu_read_lock_sched() / rcu_read_unlock_sched()
  rcu: fix sparse shadowed variable warning
  doc/RCU: fix pseudocode in rcuref.txt
  rcuclassic: fix compiler warning
  rcu: use irq-safe locks
  rcuclassic: fix compilation NG
  rcu: fix locking cleanup fallout
  rcu: remove redundant ACCESS_ONCE definition from rcupreempt.c
  rcu: fix classic RCU locking cleanup lockdep problem
  rcu: trace fix possible mem-leak
  rcu: just rename call_rcu_bh instead of making it a macro
  rcu: remove list_for_each_rcu()
  rcu: fixes to include/linux/rcupreempt.h
  rcu: classic RCU locking and memory-barrier cleanups
  rcu: prevent console flood when one CPU sees another AWOL via RCU
  rcu, debug: detect stalled grace periods, cleanups
  rcu, debug: detect stalled grace periods
  rcu classic: new algorithm for callbacks-processing(v2)
  ...
2008-10-10 13:10:51 -07:00
Jens Axboe 581d4e28d9 block: add fault injection mechanism for faking request timeouts
Only works for the generic request timer handling. Allows one to
sporadically ignore request completions, thus exercising the timeout
handling.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:17 +02:00
Tejun Heo 55dc7db70a init: DEBUG_BLOCK_EXT_DEVT requires explicit root= param
DEBUG_BLOCK_EXT_DEVT shuffles SCSI and IDE device numbers and root
device number set using rdev become meaningless.  Root devices should
be explicitly specified using textual names.  Warn about it if root
can't be found and DEBUG_BLOCK_EXT_DEVT is enabled.  Also, add warning
to the help text.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:11 +02:00
Jens Axboe 759f8ca304 Change default value of CONFIG_DEBUG_BLOCK_EXT_DEVT to 'n'
It's a debug option that you would explicitly enable to test this
feature, we should default it to 'n' to prevent accidental surprises
for now.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:11 +02:00
Tejun Heo 870d665612 block: implement CONFIG_DEBUG_BLOCK_EXT_DEVT
Extended devt introduces non-contiguos device numbers.  This patch
implements a debug option which forces most devt allocations to be
from the extended area and spreads them out.  This is enabled by
default if DEBUG_KERNEL is set and achieves...

1. Detects code paths in kernel or userland which expect predetermined
   consecutive device numbers.

2. When something goes wrong, avoid corruption as adding to the minor
   of earlier partition won't lead to the wrong but valid device.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:06 +02:00
Paul E. McKenney 2133b5d7ff rcu: RCU-based detection of stalled CPUs for Classic RCU
This patch adds stalled-CPU detection to Classic RCU.  This capability
is enabled by a new config variable CONFIG_RCU_CPU_STALL_DETECTOR, which
defaults disabled.

This is a debugging feature to detect infinite loops in kernel code, not
something that non-kernel-hackers would be expected to care about.

This feature can detect looping CPUs in !PREEMPT builds and looping CPUs
with preemption disabled in PREEMPT builds.  This is essentially a port of
this functionality from the treercu patch, replacing the stall debug patch
that is already in tip/core/rcu (commit 67182ae1c4).

The changes from the patch in tip/core/rcu include making the config
variable name match that in treercu, changing from seconds to jiffies to
avoid spurious warnings, and printing a boot message when this feature
is enabled.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-03 10:36:08 +02:00
Ingo Molnar 6003ab0bad Merge branch 'linus' into core/debug
Conflicts:
	lib/vsprintf.c

Manual merge:

	include/linux/kernel.h

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-10 09:09:51 +02:00
Arjan van de Ven 1b2439dbb7 debug: add notifier chain debugging
during some development we suspected a case where we left something
in a notifier chain that was from a module that was unloaded already...
and that sort of thing is rather hard to track down.

This patch adds a very simple sanity check (which isn't all that
expensive) to make sure the notifier we're about to call is
actually from either the kernel itself of from a still-loaded
module, avoiding a hard-to-chase-down crash.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-10 09:08:50 +02:00
Ingo Molnar 429b022af4 Merge commit 'v2.6.27-rc6' into core/rcu 2008-09-10 08:35:40 +02:00
Tony Breeds 7563dc6458 powerpc: Work around gcc's -fno-omit-frame-pointer bug
This bug is causing random crashes
(http://bugzilla.kernel.org/show_bug.cgi?id=11414).

-fno-omit-frame-pointer is only needed on powerpc when -pg is also
supplied, and there is a gcc bug that causes incorrect code generation
on 32-bit powerpc when -fno-omit-frame-pointer is used---it uses stack
locations below the stack pointer, which is not allowed by the ABI
because those locations can and sometimes do get corrupted by an
interrupt.

This ensures that CONFIG_FRAME_POINTER is only selected by ftrace.
When CONFIG_FTRACE is enabled we also pass -mno-sched-epilog to work
around the gcc codegen bug.

Patch based on work by:
	Andreas Schwab <schwab@suse.de>
	Segher Boessenkool <segher@kernel.crashing.org>

Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-09-03 20:53:34 +10:00
Andi Kleen 9e94cd325b Move sysctl check into debugging section and don't make it default y
I noticed that sysctl_check.o was the largest object file in
a allnoconfig build in kernel/*.

  36243       0       0   36243    8d93 kernel/sysctl_check.o

This is because it was default y and && EMBEDDED. But I don't
really see a need for a non kernel developer to have their
sysctls checked all the time.

So move the Kconfig into the kernel debugging section and
also drop the default y and the EMBEDDED check.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-16 17:13:43 -07:00
Randy Dunlap 3794f3e812 docsrc: build Documentation/ sources
Currently source files in the Documentation/ sub-dir can easily bit-rot
since they are not generally buildable, either because they are hidden in
text files or because there are no Makefile rules for them.  This needs to
be fixed so that the source files remain usable and good examples of code
instead of bad examples.

Add the ability to build source files that are in the Documentation/ dir.
Add to Kconfig as "BUILD_DOCSRC" config symbol.

Use "CONFIG_BUILD_DOCSRC=1 make ..." to build objects from the
Documentation/ sources.  Or enable BUILD_DOCSRC in the *config system.
However, this symbol depends on HEADERS_CHECK since the header files need
to be installed (for userspace builds).

Built (using cross-tools) for x86-64, i386, alpha, ia64, sparc32,
sparc64, powerpc, sh, m68k, & mips.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-12 16:07:30 -07:00
Paul E. McKenney 67182ae1c4 rcu, debug: detect stalled grace periods
this is a diagnostic patch for Classic RCU.

The approach is to record a timestamp at the beginning
of the grace period (in rcu_start_batch()), then have
rcu_check_callbacks() complain if:

 1.	it is running on a CPU that has holding up grace periods for
 	a long time (say one second).  This will identify the culprit
 	assuming that the culprit has not disabled hardware irqs,
 	instruction execution, or some such.

 2.	it is running on a CPU that is not holding up grace periods,
 	but grace periods have been held up for an even longer time
 	(say two seconds).

It is enabled via the default-off CONFIG_DEBUG_RCU_STALL kernel parameter.

Rather than exponential backoff, it backs off to once per 30 seconds.
My feeling upon thinking on it was that if you have stalled RCU grace
periods for that long, a few extra printk() messages are probably the
least of your worries...

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: David Witbrodt <dawitbro@sbcglobal.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-11 13:35:18 +02:00
Mel Gorman 6b74ab97bc mm: add a basic debugging framework for memory initialisation
Boot initialisation is very complex, with significant numbers of
architecture-specific routines, hooks and code ordering.  While significant
amounts of the initialisation is architecture-independent, it trusts the data
received from the architecture layer.  This is a mistake, and has resulted in
a number of difficult-to-diagnose bugs.

This patchset adds some validation and tracing to memory initialisation.  It
also introduces a few basic defensive measures.  The validation code can be
explicitly disabled for embedded systems.

This patch:

Add additional debugging and verification code for memory initialisation.

Once enabled, the verification checks are always run and when required
additional debugging information may be outputted via a mminit_loglevel=
command-line parameter.

The verification code is placed in a new file mm/mm_init.c.  Ideally other mm
initialisation code will be moved here over time.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:13 -07:00
Linus Torvalds d7b6de14a0 Merge branch 'core/softlockup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core/softlockup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  softlockup: fix invalid proc_handler for softlockup_panic
  softlockup: fix watchdog task wakeup frequency
  softlockup: fix watchdog task wakeup frequency
  softlockup: show irqtrace
  softlockup: print a module list on being stuck
  softlockup: fix NMI hangs due to lock race - 2.6.26-rc regression
  softlockup: fix false positives on nohz if CPU is 100% idle for more than 60 seconds
  softlockup: fix softlockup_thresh fix
  softlockup: fix softlockup_thresh unaligned access and disable detection at runtime
  softlockup: allow panic on lockup
2008-07-23 18:34:13 -07:00
Robert P. J. Day ff543332ec debugfs: Add a reference to the debugfs API documentation.
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Cc: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:54:40 -07:00
Ingo Molnar 1e09481365 Merge branch 'linus' into core/softlockup
Conflicts:

	kernel/softlockup.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-15 23:12:58 +02:00
Ingo Molnar 6c9fcaf2ee Merge branch 'core/rcu' into core/rcu-for-linus 2008-07-15 21:10:12 +02:00
Linus Torvalds af5329cdf5 Merge branch 'core/stacktrace' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core/stacktrace' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  generic-ipi: powerpc/generic-ipi tree build failure
  stacktrace: fix build failure on sparc64
  stacktrace: export save_stack_trace[_tsk]
  stacktrace: fix modular build, export print_stack_trace and save_stack_trace
  backtrace: replace timer with tasklet + completions
  stacktrace: add saved stack traces to backtrace self-test
  stacktrace: print_stack_trace() cleanup
  debugging: make stacktrace independent from DEBUG_KERNEL
  stacktrace: don't crash on invalid stack trace structs
2008-07-15 10:31:35 -07:00
Vegard Nossum ad118c54a3 stacktrace: add saved stack traces to backtrace self-test
This patch adds saved stack-traces to the backtrace suite of self-tests.

Note that we don't depend on or unconditionally enable CONFIG_STACKTRACE
because not all architectures may have it (and we still want to enable the
other tests for those architectures).

Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-27 18:09:15 +02:00
Jiri Slaby 59ea746337 MM: virtual address debug
Add some (configurable) expensive sanity checking to catch wrong address
translations on x86.

- create linux/mmdebug.h file to be able include this file in
  asm headers to not get unsolvable loops in header files
- __phys_addr on x86_32 became a function in ioremap.c since
  PAGE_OFFSET, is_vmalloc_addr and VMALLOC_* non-constasts are undefined
  if declared in page_32.h
- add __phys_addr_const for initializing doublefault_tss.__cr3

Tested on 386, 386pae, x86_64 and x86_64 numa=fake=2.

Contains Andi's enable numa virtual address debug patch.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-19 13:31:42 +02:00
Paul E. McKenney 31a72bce0b rcu: make rcutorture more vicious: reinstate boot-time testing
This patch re-institutes the ability to build rcutorture directly into
the Linux kernel.  The reason that this capability was removed was that
this could result in your kernel being pretty much useless, as rcutorture
would be running starting from early boot.  This problem has been avoided
by (1) making rcutorture run only three seconds of every six by default,
(2) adding a CONFIG_RCU_TORTURE_TEST_RUNNABLE that permits rcutorture
to be quiesced at boot time, and (3) adding a sysctl in /proc named
/proc/sys/kernel/rcutorture_runnable that permits rcutorture to be
quiesced and unquiesced when built into the kernel.

Please note that this /proc file is -not- available when rcutorture
is built as a module.  Please also note that to get the earlier
take-no-prisoners behavior, you must use the boot command line to set
rcutorture's "stutter" parameter to zero.

The rcutorture quiescing mechanism is currently quite crude: loops
in each rcutorture process that poll a global variable once per tick.
Suggestions for improvement are welcome.  The default action will
be to reduce the polling rate to a few times per second.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Suggested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-19 11:22:15 +02:00
Ingo Molnar 1462a20005 Revert "prohibit rcutorture from being compiled into the kernel"
This reverts commit 9aaffc898f.

That commit was a very bad idea. RCU_TORTURE found many boot timing
bugs and other sorts of bugs in the past, so excluding it from
boot images is very silly.

The option already depends on DEBUG_KERNEL and is disabled by default.
Even when it runs, the test threads are reniced. If it annoys people
we could add a runtime sysctl.
2008-06-16 08:40:04 +02:00
Ingo Molnar 886dd58258 debugging: make stacktrace independent from DEBUG_KERNEL
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 15:55:20 +02:00
Ingo Molnar 9c44bc03ff softlockup: allow panic on lockup
allow users to configure the softlockup detector to generate a panic
instead of a warning message.

high-availability systems might opt for this strict method (combined
with panic_timeout= boot option/sysctl), instead of generating
softlockup warnings ad infinitum.

also, automated tests work better if the system reboots reliably (into
a safe kernel) in case of a lockup.

The full spectrum of configurability is supported: boot option, sysctl
option and Kconfig option.

it's default-disabled.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 06:34:44 +02:00
Arnaldo Carvalho de Melo 16444a8a40 ftrace: add basic support for gcc profiler instrumentation
If CONFIG_FTRACE is selected and /proc/sys/kernel/ftrace_enabled is
set to a non-zero value the ftrace routine will be called everytime
we enter a kernel function that is not marked with the "notrace"
attribute.

The ftrace routine will then call a registered function if a function
happens to be registered.

[ This code has been highly hacked by Steven Rostedt and Ingo Molnar,
  so don't blame Arnaldo for all of this ;-) ]

Update:
  It is now possible to register more than one ftrace function.
  If only one ftrace function is registered, that will be the
  function that ftrace calls directly. If more than one function
  is registered, then ftrace will call a function that will loop
  through the functions to call.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 20:31:58 +02:00
Thomas Gleixner c6f3a97f86 debugobjects: add timer specific object debugging code
Add calls to the generic object debugging infrastructure and provide fixup
functions which allow to keep the system alive when recoverable problems have
been detected by the object debugging core code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Greg KH <greg@kroah.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:53 -07:00
Thomas Gleixner 3ac7fe5a4a infrastructure to debug (dynamic) objects
We can see an ever repeating problem pattern with objects of any kind in the
kernel:

1) freeing of active objects
2) reinitialization of active objects

Both problems can be hard to debug because the crash happens at a point where
we have no chance to decode the root cause anymore.  One problem spot are
kernel timers, where the detection of the problem often happens in interrupt
context and usually causes the machine to panic.

While working on a timer related bug report I had to hack specialized code
into the timer subsystem to get a reasonable hint for the root cause.  This
debug hack was fine for temporary use, but far from a mergeable solution due
to the intrusiveness into the timer code.

The code further lacked the ability to detect and report the root cause
instantly and keep the system operational.

Keeping the system operational is important to get hold of the debug
information without special debugging aids like serial consoles and special
knowledge of the bug reporter.

The problems described above are not restricted to timers, but timers tend to
expose it usually in a full system crash.  Other objects are less explosive,
but the symptoms caused by such mistakes can be even harder to debug.

Instead of creating specialized debugging code for the timer subsystem a
generic infrastructure is created which allows developers to verify their code
and provides an easy to enable debug facility for users in case of trouble.

The debugobjects core code keeps track of operations on static and dynamic
objects by inserting them into a hashed list and sanity checking them on
object operations and provides additional checks whenever kernel memory is
freed.

The tracked object operations are:
- initializing an object
- adding an object to a subsystem list
- deleting an object from a subsystem list

Each operation is sanity checked before the operation is executed and the
subsystem specific code can provide a fixup function which allows to prevent
the damage of the operation.  When the sanity check triggers a warning message
and a stack trace is printed.

The list of operations can be extended if the need arises.  For now it's
limited to the requirements of the first user (timers).

The core code enqueues the objects into hash buckets.  The hash index is
generated from the address of the object to simplify the lookup for the check
on kfree/vfree.  Each bucket has it's own spinlock to avoid contention on a
global lock.

The debug code can be compiled in without being active.  The runtime overhead
is minimal and could be optimized by asm alternatives.  A kernel command line
option enables the debugging code.

Thanks to Ingo Molnar for review, suggestions and cleanup patches.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Greg KH <greg@kroah.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:53 -07:00
Andi Kleen 35bb5b1e0e Add option to enable -Wframe-larger-than= on gcc 4.4
Add option to enable -Wframe-larger-than= on gcc 4.4

gcc mainline (upcoming 4.4) added a new -Wframe-larger-than=...
option to warn at build time about too large stack frames. Add a config
option to enable this warning, since this very useful for the kernel.

I choose (somewhat arbitarily) 2048 as default warning threshold for 64bit
and 1024 as default for 32bit architectures.  With some research and
fixing all the code for smaller values these defaults should be probably
lowered.

With the default allyesconfigs have some new warnings, but I think
that is all code that should be just fixed.

At some point (when gcc 4.4 is released and widely used) this should
obsolete make checkstack

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-04-25 20:23:47 +02:00
Dave Hansen ad775f5a8f [PATCH] r/o bind mounts: debugging for missed calls
There have been a few oopses caused by 'struct file's with NULL f_vfsmnts.
There was also a set of potentially missed mnt_want_write()s from
dentry_open() calls.

This patch provides a very simple debugging framework to catch these kinds of
bugs.  It will WARN_ON() them, but should stop us from having any oopses or
mnt_writer count imbalances.

I'm quite convinced that this is a good thing because it found bugs in the
stuff I was working on as soon as I wrote it.

[hch: made it conditional on a debug option.
      But it's still a little bit too ugly]

[hch: merged forced remount r/o fix from Dave and akpm's fix for the fix]

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-19 00:29:28 -04:00
Linus Torvalds eddeb0e2d8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6: (43 commits)
  firewire: cleanups
  firewire: fix synchronization of gap counts
  firewire: wait until PHY configuration packet was transmitted (fix bus reset loop)
  firewire: remove unused struct member
  firewire: use bitwise and to get reg in handle_registers
  firewire: replace more hex values with defined csr constants
  firewire: reread config ROM when device reset the bus
  firewire: replace static ROM cache by allocated cache
  firewire: fw-ohci: work around generation bug in TI controllers (fix AV/C and more)
  firewire: fw-ohci: extend logging of bus generations and node ID
  firewire: fw-ohci: conditionally log busReset interrupts
  firewire: fw-ohci: don't append to AT context when it's not active
  firewire: fw-ohci: log regAccessFail events
  firewire: fw-ohci: make sure HCControl register LPS bit is set
  firewire: fw-ohci: missing PPC PMac feature calls in failure path
  firewire: fw-ohci: untangle a mixed unsigned/signed expression
  firewire: debug interrupt events
  firewire: fw-ohci: catch self_id_count == 0
  firewire: fw-ohci: add self ID error check
  firewire: fw-ohci: refactor probe, remove, suspend, resume
  ...
2008-04-18 11:24:29 -07:00
Stefan Richter 080de8c2c5 firewire: fw-ohci: add option for remote debugging
This way firewire-ohci can be used for remote debugging like ohci1394.
Version with amendment from Fri, 11 Apr 2008 00:08:08 +0200.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Acked-by: Bernhard Kaindl <bk@suse.de>
2008-04-18 17:55:33 +02:00
Linus Torvalds 9732b61123 Merge git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-kgdb
* git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-kgdb:
  kgdb: always use icache flush for sw breakpoints
  kgdb: fix SMP NMI kgdb_handle_exception exit race
  kgdb: documentation fixes
  kgdb: allow static kgdbts boot configuration
  kgdb: add documentation
  kgdb: Kconfig fix
  kgdb: add kgdb internal test suite
  kgdb: fix several kgdb regressions
  kgdb: kgdboc pl011 I/O module
  kgdb: fix optional arch functions and probe_kernel_*
  kgdb: add x86 HW breakpoints
  kgdb: print breakpoint removed on exception
  kgdb: clocksource watchdog
  kgdb: fix NMI hangs
  kgdb: fix kgdboc dynamic module configuration
  kgdb: document parameters
  x86: kgdb support
  consoles: polling support, kgdboc
  kgdb: core
  uaccess: add probe_kernel_write()
2008-04-18 08:37:01 -07:00
Linus Torvalds d7bb545d86 Merge branch 'semaphore' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc
* 'semaphore' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc:
  Remove DEBUG_SEMAPHORE from Kconfig
  Improve semaphore documentation
  Simplify semaphore implementation
  Add down_timeout and change ACPI to use it
  Introduce down_killable()
  Generic semaphore implementation
  Add semaphore.h to kernel_lock.c
  Fix quota.h includes
2008-04-18 08:25:29 -07:00
Jason Wessel dc7d552705 kgdb: core
kgdb core code. Handles the protocol and the arch details.

[ mingo@elte.hu: heavily modified, simplified and cleaned up. ]
[ xemul@openvz.org: use find_task_by_pid_ns ]

Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jan Kiszka <jan.kiszka@web.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-17 20:05:37 +02:00
Matthew Wilcox 2342e51ba2 Remove DEBUG_SEMAPHORE from Kconfig
Alpha and FRV mutexes had an option to print lots of debugging messages
in their semaphore implementation.  This feature has not been carried
over to the generic semaphores, so remove the stale Kconfig option.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2008-04-17 10:53:01 -04:00
Christoph Lameter 5b06c853ad slub: Deal with config variable dependencies
count_partial() is used by both slabinfo and the sysfs proc support. Move
the function directly before the beginning of the sysfs code so that it can
be easily found. Rework the preprocessor conditional to take into account
that slub sysfs support depends on CONFIG_SYSFS *and* CONFIG_SLUB_DEBUG.

Make CONFIG_SLUB_STATS depend on CONFIG_SLUB_DEBUG and CONFIG_SYSFS. There
is no point of keeping statistics if no one can restrive them.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
2008-04-14 18:51:34 +03:00
Chris Snook fddd9cf82c make LKDTM depend on BLOCK
Make LKDTM depend on BLOCK to prevent build failures with certain configs.

Signed-off-by: Chris Snook <csnook@redhat.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-23 17:12:13 -08:00
Sam Ravnborg fa2144ba9a kbuild: explain why DEBUG_SECTION_MISMATCH is UNDEFINED
We started to see patches enabling this - so explain why
it is disabled and the condition to enable it again.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-02-15 13:53:11 +01:00
Harvey Harrison 185c045c24 x86, core: remove CONFIG_FORCED_INLINING
Other than the defconfigs, remove the entry in compiler-gcc4.h,
Kconfig.debug and feature-removal-schedule.txt.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-02-09 23:24:09 +01:00
David Howells b920de1b77 mn10300: add the MN10300/AM33 architecture to the kernel
Add architecture support for the MN10300/AM33 CPUs produced by MEI to the
kernel.

This patch also adds board support for the ASB2303 with the ASB2308 daughter
board, and the ASB2305.  The only processor supported is the MN103E010, which
is an AM33v2 core plus on-chip devices.

[akpm@linux-foundation.org: nuke cvs control strings]
Signed-off-by: Masakazu Urade <urade.masakazu@jp.panasonic.com>
Signed-off-by: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:30 -08:00
Christoph Lameter 8ff12cfc00 SLUB: Support for performance statistics
The statistics provided here allow the monitoring of allocator behavior but
at the cost of some (minimal) loss of performance. Counters are placed in
SLUB's per cpu data structure. The per cpu structure may be extended by the
statistics to grow larger than one cacheline which will increase the cache
footprint of SLUB.

There is a compile option to enable/disable the inclusion of the runtime
statistics and its off by default.

The slabinfo tool is enhanced to support these statistics via two options:

-D 	Switches the line of information displayed for a slab from size
	mode to activity mode.

-A	Sorts the slabs displayed by activity. This allows the display of
	the slabs most important to the performance of a certain load.

-r	Report option will report detailed statistics on

Example (tbench load):

slabinfo -AD		->Shows the most active slabs

Name                   Objects    Alloc     Free   %Fast
skbuff_fclone_cache         33 111953835 111953835  99  99
:0000192                  2666  5283688  5281047  99  99
:0001024                   849  5247230  5246389  83  83
vm_area_struct            1349   119642   118355  91  22
:0004096                    15    66753    66751  98  98
:0000064                  2067    25297    23383  98  78
dentry                   10259    28635    18464  91  45
:0000080                 11004    18950     8089  98  98
:0000096                  1703    12358    10784  99  98
:0000128                   762    10582     9875  94  18
:0000512                   184     9807     9647  95  81
:0002048                   479     9669     9195  83  65
anon_vma                   777     9461     9002  99  71
kmalloc-8                 6492     9981     5624  99  97
:0000768                   258     7174     6931  58  15

So the skbuff_fclone_cache is of highest importance for the tbench load.
Pretty high load on the 192 sized slab. Look for the aliases

slabinfo -a | grep 000192
:0000192     <- xfs_btree_cur filp kmalloc-192 uid_cache tw_sock_TCP
	request_sock_TCPv6 tw_sock_TCPv6 skbuff_head_cache xfs_ili

Likely skbuff_head_cache.


Looking into the statistics of the skbuff_fclone_cache is possible through

slabinfo skbuff_fclone_cache	->-r option implied if cache name is mentioned


.... Usual output ...

Slab Perf Counter       Alloc     Free %Al %Fr
--------------------------------------------------
Fastpath             111953360 111946981  99  99
Slowpath                 1044     7423   0   0
Page Alloc                272      264   0   0
Add partial                25      325   0   0
Remove partial             86      264   0   0
RemoteObj/SlabFrozen      350     4832   0   0
Total                111954404 111954404

Flushes       49 Refill        0
Deactivate Full=325(92%) Empty=0(0%) ToHead=24(6%) ToTail=1(0%)

Looks good because the fastpath is overwhelmingly taken.


skbuff_head_cache:

Slab Perf Counter       Alloc     Free %Al %Fr
--------------------------------------------------
Fastpath              5297262  5259882  99  99
Slowpath                 4477    39586   0   0
Page Alloc                937      824   0   0
Add partial                 0     2515   0   0
Remove partial           1691      824   0   0
RemoteObj/SlabFrozen     2621     9684   0   0
Total                 5301739  5299468

Deactivate Full=2620(100%) Empty=0(0%) ToHead=0(0%) ToTail=0(0%)


Descriptions of the output:

Total:		The total number of allocation and frees that occurred for a
		slab

Fastpath:	The number of allocations/frees that used the fastpath.

Slowpath:	Other allocations

Page Alloc:	Number of calls to the page allocator as a result of slowpath
		processing

Add Partial:	Number of slabs added to the partial list through free or
		alloc (occurs during cpuslab flushes)

Remove Partial:	Number of slabs removed from the partial list as a result of
		allocations retrieving a partial slab or by a free freeing
		the last object of a slab.

RemoteObj/Froz:	How many times were remotely freed object encountered when a
		slab was about to be deactivated. Frozen: How many times was
		free able to skip list processing because the slab was in use
		as the cpuslab of another processor.

Flushes:	Number of times the cpuslab was flushed on request
		(kmem_cache_shrink, may result from races in __slab_alloc)

Refill:		Number of times we were able to refill the cpuslab from
		remotely freed objects for the same slab.

Deactivate:	Statistics how slabs were deactivated. Shows how they were
		put onto the partial list.

In general fastpath is very good. Slowpath without partial list processing is
also desirable. Any touching of partial list uses node specific locks which
may potentially cause list lock contention.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
2008-02-07 17:47:41 -08:00
Geert Uytterhoeven d6fbfa4fce kbuild: Spelling/grammar fixes for config DEBUG_SECTION_MISMATCH
Including additional fixes from Randy Dunlap <randy.dunlap@oracle.com>

Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-02-03 08:58:07 +01:00
Sam Ravnborg e5f95c8b77 kbuild: print only total number of section mismatces found
We have too many section mismatches detected at the moment.
So silence modpost and prevent the option from being
set in a typical allyesconfig build.

Tell the user how to see all the deteils in the summary
message from modpost.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-02-03 08:58:07 +01:00
Heiko Carstens aa7d93506c latencytop: Change Kconfig dependency.
Change latencytop Kconfig entry so it doesn't list the archictectures
that support it. Instead introduce HAVE_LATENCY_SUPPORT which any
architecture can set. Should reduce patch conflicts.

Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Holger Wolf <wolf@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-02-01 17:45:14 +01:00
Bernhard Kaindl f212ec4b7b x86: early boot debugging via FireWire (ohci1394_dma=early)
This patch adds a new configuration option, which adds support for a new
early_param which gets checked in arch/x86/kernel/setup_{32,64}.c:setup_arch()
to decide wether OHCI-1394 FireWire controllers should be initialized and
enabled for physical DMA access to allow remote debugging of early problems
like issues ACPI or other subsystems which are executed very early.

If the config option is not enabled, no code is changed, and if the boot
paramenter is not given, no new code is executed, and independent of that,
all new code is freed after boot, so the config option can be even enabled
in standard, non-debug kernels.

With specialized tools, it is then possible to get debugging information
from machines which have no serial ports (notebooks) such as the printk
buffer contents, or any data which can be referenced from global pointers,
if it is stored below the 4GB limit and even memory dumps of of the physical
RAM region below the 4GB limit can be taken without any cooperation from the
CPU of the host, so the machine can be crashed early, it does not matter.

In the extreme, even kernel debuggers can be accessed in this way. I wrote
a small kgdb module and an accompanying gdb stub for FireWire which allows
to gdb to talk to kgdb using remote remory reads and writes over FireWire.

An version of the gdb stub fore FireWire is able to read all global data
from a system which is running a a normal kernel without any kernel debugger,
without any interruption or support of the system's CPU. That way, e.g. the
task struct and so on can be read and even manipulated when the physical DMA
access is granted.

A HOWTO is included in this patch, in Documentation/debugging-via-ohci1394.txt
and I've put a copy online at
ftp://ftp.suse.de/private/bk/firewire/docs/debugging-via-ohci1394.txt

It also has links to all the tools which are available to make use of it
another copy of it is online at:
ftp://ftp.suse.de/private/bk/firewire/kernel/ohci1394_dma_early-v2.diff

Signed-Off-By: Bernhard Kaindl <bk@suse.de>
Tested-By: Thomas Renninger <trenn@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:34:11 +01:00
Arjan van de Ven 6dab27784b x86: add a simple backtrace test module
During the work on the x86 32 and 64 bit backtrace code I found it useful
to have a simple test module to test a process and irq context backtrace.
Since the existing backtrace code was buggy, I figure it might be useful
to have such a test module in the kernel so that maybe we can even
detect such bugs earlier..

[ mingo@elte.hu: build fix ]

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:33:08 +01:00
Ananth N Mavinakayanahalli 8c1c935642 x86: kprobes: add kprobes smoke tests that run on boot
Here is a quick and naive smoke test for kprobes. This is intended to
just verify if some unrelated change broke the *probes subsystem. It is
self contained, architecture agnostic and isn't of any great use by itself.

This needs to be built in the kernel and runs a basic set of tests to
verify if kprobes, jprobes and kretprobes run fine on the kernel. In case
of an error, it'll print out a message with a "BUG" prefix.

This is a start; we intend to add more tests to this bucket over time.

Thanks to Jim Keniston and Masami Hiramatsu for comments and suggestions.

Tested on x86 (32/64) and powerpc.

Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-30 13:32:53 +01:00
Sam Ravnborg 588ccd732b kbuild: add verbose option to Section mismatch reporting in modpost
If the config option CONFIG_SECTION_MISMATCH is not set and
we see a Section mismatch present the following to the user:

modpost: Found 1 section mismatch(es).
To see additional details select "Enable full Section mismatch analysis"
in the Kernel Hacking menu (CONFIG_SECTION_MISMATCH).

If the option CONFIG_SECTION_MISMATCH is selected
then be verbose in the Section mismatch reporting from mdopost.
Sample outputs:

WARNING: o-x86_64/vmlinux.o(.text+0x7396): Section mismatch in reference from the function discover_ebda() to the variable .init.data:ebda_addr
The function  discover_ebda() references
the variable __initdata ebda_addr.
This is often because discover_ebda lacks a __initdata
annotation or the annotation of ebda_addr is wrong.

WARNING: o-x86_64/vmlinux.o(.data+0x74d58): Section mismatch in reference from the variable pci_serial_quirks to the function .devexit.text:pci_plx9050_exit()
The variable pci_serial_quirks references
the function __devexit pci_plx9050_exit()
If the reference is valid then annotate the
variable with __exit* (see linux/init.h) or name the variable:
*driver, *_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console,

WARNING: o-x86_64/vmlinux.o(__ksymtab+0x630): Section mismatch in reference from the variable __ksymtab_arch_register_cpu to the function .cpuinit.text:arch_register_cpu()
The symbol arch_register_cpu is exported and annotated __cpuinit
Fix this by removing the __cpuinit annotation of arch_register_cpu or drop the export.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-28 23:21:18 +01:00
Sam Ravnborg 91341d4b2c kbuild: introduce new option to enhance section mismatch analysis
Setting the option DEBUG_SECTION_MISMATCH will
report additional section mismatch'es but this
should in the end makes it possible to get rid of
all of them.

See help text in lib/Kconfig.debug for details.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-28 23:21:18 +01:00
Arjan van de Ven 9745512ce7 sched: latencytop support
LatencyTOP kernel infrastructure; it measures latencies in the
scheduler and tracks it system wide and per process.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-25 21:08:34 +01:00
Mike Frysinger 529a73fbae Blackfin arch: punt CONFIG_BFIN -- we already have CONFIG_BLACKFIN
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-11-23 14:28:44 +08:00
Jeff Garzik de48844398 Permit silencing of __deprecated warnings.
The __deprecated marker is quite useful in highlighting the remnants of
old APIs that want removing.

However, it is quite normal for one or more years to pass, before the
(usually ancient, bitrotten) code in question is either updated or
deleted.

Thus, like __must_check, add a Kconfig option that permits the silencing
of this compiler warning.

This change mimics the ifdef-ery and Kconfig defaults of MUST_CHECK as
closely as possible.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-25 15:10:17 -07:00
Jens Axboe d6ec084200 Add CONFIG_DEBUG_SG sg validation
Add a Kconfig entry which will toggle some sanity checks on the sg
entry and tables.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-22 21:20:03 +02:00
Mathieu Desnoyers 267c4025f2 markers: Add samples subdir
Begin infrastructure for kernel code samples in the samples/ directory.
Add its Kconfig and Kbuild files.
Source its Kconfig file in all arch/ Kconfigs.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:55 -07:00
Randy Dunlap bfe8df3d31 slow down printk during boot
Optionally add a boot delay after each kernel printk() call, crudely
measured in milliseconds, with a maximum delay of 10 seconds per printk.

Enable CONFIG_BOOT_PRINTK_DELAY=y and then add (e.g.):
"lpj=loops_per_jiffy boot_delay=100"
to the kernel command line.

It has been useful in cases like "during boot, my machine just reboots or the
screen goes black" by slowing down printk, (and adding initcall_debug), we can
usually see the last thing that happened before the lights went out which is
usually a valuable clue.

[akpm@linux-foundation.org: not all architectures implement CONFIG_HZ]
[akpm@linux-foundation.org: fix lots of stuff]
[bunk@stusta.de: kernel/printk.c: make 2 variables static]
[heiko.carstens@de.ibm.com: fix slow down printk on boot compile error]
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:42:49 -07:00
Linus Torvalds e86908614f Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (408 commits)
  [POWERPC] Add memchr() to the bootwrapper
  [POWERPC] Implement logging of unhandled signals
  [POWERPC] Add legacy serial support for OPB with flattened device tree
  [POWERPC] Use 1TB segments
  [POWERPC] XilinxFB: Allow fixed framebuffer base address
  [POWERPC] XilinxFB: Add support for custom screen resolution
  [POWERPC] XilinxFB: Use pdata to pass around framebuffer parameters
  [POWERPC] PCI: Add 64-bit physical address support to setup_indirect_pci
  [POWERPC] 4xx: Kilauea defconfig file
  [POWERPC] 4xx: Kilauea DTS
  [POWERPC] 4xx: Add AMCC Kilauea eval board support to platforms/40x
  [POWERPC] 4xx: Add AMCC 405EX support to cputable.c
  [POWERPC] Adjust TASK_SIZE on ppc32 systems to 3GB that are capable
  [POWERPC] Use PAGE_OFFSET to tell if an address is user/kernel in SW TLB handlers
  [POWERPC] 85xx: Enable FP emulation in MPC8560 ADS defconfig
  [POWERPC] 85xx: Killed <asm/mpc85xx.h>
  [POWERPC] 85xx: Add cpm nodes for 8541/8555 CDS
  [POWERPC] 85xx: Convert mpc8560ads to the new CPM binding.
  [POWERPC] mpc8272ads: Remove muram from the CPM reg property.
  [POWERPC] Make clockevents work on PPC601 processors
  ...

Fixed up conflict in Documentation/powerpc/booting-without-of.txt manually.
2007-10-11 21:55:47 -07:00
Peter Zijlstra a560aa48ee lockstat: documentation
Provide some documentation for CONFIG_LOCK_STAT.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Cc: Rob Landley <rob@landley.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-07 16:28:43 -07:00
Paul Mackerras 70f227d884 Merge branch 'linux-2.6' into for-2.6.24 2007-10-03 15:33:17 +10:00
Hugh Dickins 048c8bc90e [POWERPC] ppc64: support CONFIG_DEBUG_PREEMPT
Add CONFIG_DEBUG_PREEMPT support to ppc64: it was useful for testing
get_paca() preemption.  Cheat a little, just use debug_smp_processor_id()
in the debug version of get_paca(): it contains all the right checks and
reporting, though get_paca() doesn't really use smp_processor_id().

Use local_paca for what might have been called __raw_get_paca().
Silence harmless warnings from io.h and lparcfg.c with local_paca -
it is okay for iseries_lparcfg_data to be referencing shared_proc
with preemption enabled: all cpus should show the same value for
shared_proc.

Why do other architectures need TRACE_IRQFLAGS_SUPPORT for DEBUG_PREEMPT?
I don't know, ppc64 appears to get along fine without it.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-10-03 11:48:44 +10:00
Danny ter Haar fdfb870f8e typo fix Kernel config option
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-09-25 08:51:04 -07:00
Adrian Bunk 99eb8a550d Remove the arm26 port
The arm26 port has been in a state where it was far from even compiling
for quite some time.

Ian Molton agreed with the removal.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Ian Molton <spyro@f2s.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-31 15:39:39 -07:00
Peter Zijlstra f20786ff4d lockstat: core infrastructure
Introduce the core lock statistics code.

Lock statistics provides lock wait-time and hold-time (as well as the count
of corresponding contention and acquisitions events). Also, the first few
call-sites that encounter contention are tracked.

Lock wait-time is the time spent waiting on the lock. This provides insight
into the locking scheme, that is, a heavily contended lock is indicative of
a too coarse locking scheme.

Lock hold-time is the duration the lock was held, this provides a reference for
the wait-time numbers, so they can be put into perspective.

  1)
    lock
  2)
    ... do stuff ..
    unlock
  3)

The time between 1 and 2 is the wait-time. The time between 2 and 3 is the
hold-time.

The lockdep held-lock tracking code is reused, because it already collects locks
into meaningful groups (classes), and because it is an existing infrastructure
for lock instrumentation.

Currently lockdep tracks lock acquisition with two hooks:

  lock()
    lock_acquire()
    _lock()

 ... code protected by lock ...

  unlock()
    lock_release()
    _unlock()

We need to extend this with two more hooks, in order to measure contention.

  lock_contended() - used to measure contention events
  lock_acquired()  - completion of the contention

These are then placed the following way:

  lock()
    lock_acquire()
    if (!_try_lock())
      lock_contended()
      _lock()
      lock_acquired()

 ... do locked stuff ...

  unlock()
    lock_release()
    _unlock()

(Note: the try_lock() 'trick' is used to avoid instrumenting all platform
       dependent lock primitive implementations.)

It is also possible to toggle the two lockdep features at runtime using:

  /proc/sys/kernel/prove_locking
  /proc/sys/kernel/lock_stat

(esp. turning off the O(n^2) prove_locking functionaliy can help)

[akpm@linux-foundation.org: build fixes]
[akpm@linux-foundation.org: nuke unneeded ifdefs]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:49 -07:00
Christoph Lameter f0630fff54 SLUB: support slub_debug on by default
Add a new configuration variable

CONFIG_SLUB_DEBUG_ON

If set then the kernel will be booted by default with slab debugging
switched on. Similar to CONFIG_SLAB_DEBUG. By default slab debugging
is available but must be enabled by specifying "slub_debug" as a
kernel parameter.

Also add support to switch off slab debugging for a kernel that was
built with CONFIG_SLUB_DEBUG_ON. This works by specifying

slub_debug=-

as a kernel parameter.

Dave Jones wanted this feature.
http://marc.info/?l=linux-kernel&m=118072189913045&w=2

[akpm@linux-foundation.org: clean up switch statement]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:36 -07:00
Ingo Molnar b642b6d3fa sched: scheduler debugging, enable in Kconfig
enable CONFIG_SCHED_DEBUG in lib/Kconfig.debug.

the runtime overhead of this option is very small.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-07-09 18:52:00 +02:00
Ingo Molnar c1a834dc70 timer stats: speedups
Make timer-stats have almost zero overhead when enabled in the config but
not used.  (this way distros can enable it more easily)

Also update the documentation about overhead of timer_stats - it was
written for the first version which had a global lock and a linear list
walk based lookup ;-)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-01 08:18:30 -07:00
Paul E. McKenney 9aaffc898f prohibit rcutorture from being compiled into the kernel
There have been a number of instances where people have accidentally compiled
rcutorture into the kernel (CONFIG_RCU_TORTURE_TEST=y), which has never been
useful, and has often resulted in great frustration.

The attached patch prohibits rcutorture from being compiled into the
kernel.  It may be excluded altogether or compiled as a module.  People
wishing to have rcutorture hammer their machine immediately upon boot
are free to hand-edit lib/Kconfig.debug to remove the "depends on m"
line.

Thanks to Randy Dunlap for the trick that makes this work.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Josh Triplett <josh@kernel.org>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-23 20:14:12 -07:00
Akinobu Mita 6d690dcac9 fault injection: disable stacktrace filter for x86-64
Disable stacktrace filter support for x86-64 for now.  Will be enable when we
can get the dwarf2 unwinder back.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-12 10:55:39 -07:00
Alistair John Strachan 794543a236 Move LOG_BUF_SHIFT to a more sensible place
Several people have observed that perhaps LOG_BUF_SHIFT should be in a more
obvious place than under DEBUG_KERNEL. Under some circumstances (such as the
PARISC architecture), DEBUG_KERNEL can increase kernel size, which is an
undesirable trade off for something as trivial as increasing the kernel log
buffer size.

Instead, move LOG_BUF_SHIFT into "General Setup", so that people are more
likely to be able to change it such a circumstance that the default buffer
size is insufficient.

Signed-off-by: Alistair John Strachan <s0348365@sms.ed.ac.uk>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:14 -07:00
Robert P. J. Day c761c84154 kconfig: centralize the selection of semaphore debugging in lib/Kconfig.debug
Remove the Kconfig selection of semaphore debugging from the ALPHA and FRV
Kconfig files, and centralize it in lib/Kconfig.debug.

There doesn't seem to be much point in letting individual architectures
independently define the same Kconfig option when it can just as easily be
put in a single Kconfig file and made dependent on a subset of
architectures.  that way, at least the option shows up in the same relative
location in the menu each time.

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:00 -07:00
Bryan Wu 1394f03221 blackfin architecture
This adds support for the Analog Devices Blackfin processor architecture, and
currently supports the BF533, BF532, BF531, BF537, BF536, BF534, and BF561
(Dual Core) devices, with a variety of development platforms including those
avaliable from Analog Devices (BF533-EZKit, BF533-STAMP, BF537-STAMP,
BF561-EZKIT), and Bluetechnix!  Tinyboards.

The Blackfin architecture was jointly developed by Intel and Analog Devices
Inc.  (ADI) as the Micro Signal Architecture (MSA) core and introduced it in
December of 2000.  Since then ADI has put this core into its Blackfin
processor family of devices.  The Blackfin core has the advantages of a clean,
orthogonal,RISC-like microprocessor instruction set.  It combines a dual-MAC
(Multiply/Accumulate), state-of-the-art signal processing engine and
single-instruction, multiple-data (SIMD) multimedia capabilities into a single
instruction-set architecture.

The Blackfin architecture, including the instruction set, is described by the
ADSP-BF53x/BF56x Blackfin Processor Programming Reference
http://blackfin.uclinux.org/gf/download/frsrelease/29/2549/Blackfin_PRM.pdf

The Blackfin processor is already supported by major releases of gcc, and
there are binary and source rpms/tarballs for many architectures at:
http://blackfin.uclinux.org/gf/project/toolchain/frs There is complete
documentation, including "getting started" guides available at:
http://docs.blackfin.uclinux.org/ which provides links to the sources and
patches you will need in order to set up a cross-compiling environment for
bfin-linux-uclibc

This patch, as well as the other patches (toolchain, distribution,
uClibc) are actively supported by Analog Devices Inc, at:
http://blackfin.uclinux.org/

We have tested this on LTP, and our test plan (including pass/fails) can
be found at:
http://docs.blackfin.uclinux.org/doku.php?id=testing_the_linux_kernel

[m.kozlowski@tuxland.pl: balance parenthesis in blackfin header files]
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
Signed-off-by: Mariusz Kozlowski <m.kozlowski@tuxland.pl>
Signed-off-by: Aubrey Li <aubrey.li@analog.com>
Signed-off-by: Jie Zhang <jie.zhang@analog.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-07 12:12:58 -07:00
Andreas Dilger b72e53f8bb kconfig.debug: clarify CONFIG_DEBUG_INFO help text
The following patch adds some extra clarification to the CONFIG_DEBUG_INFO
Kconfig help text.  The current text is mostly a recursive definition and
doesn't really say much of anything.  When I first read this I thought it
was going to enable extra verbosity in debug messages or something, but it
is only enabling the "gcc -g" compile option in the Makefile.

Signed-off-by: Andreas Dilger <adilger@clusterfs.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-05-02 20:58:09 +02:00
Franck Bui-Huu 14cf232ab1 [MIPS] Don't force frame pointers for lockdep on MIPS
Stacktrace support on MIPS doesn't use frame pointers.  Since this option
considerably increases the size of the kernel code, force lockdep to not
use it.

Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-04-27 16:20:26 +01:00
Akinobu Mita 1df49008f4 [PATCH] fault injection: split up stacktrace filter Kconfig option
There is no prompt for CONFIG_STACKTRACE, so FAULT_INJECTION cannot be
selected without LOCKDEP enabled.  (found by Paolo 'Blaisorblade'
Giarrusso)

In order to fix such broken Kconfig dependency, this patch splits up the
stacktrace filter support for fault injection by new Kconfig option, which
enables to use fault injection on the architecture which doesn't have
general stacktrace support.

Cc: "Paolo 'Blaisorblade' Giarrusso" <blaisorblade@yahoo.it>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-20 17:10:14 -08:00
Ingo Molnar 82f67cd9fc [PATCH] Add debugging feature /proc/timer_stat
Add /proc/timer_stats support: debugging feature to profile timer expiration.
Both the starting site, process/PID and the expiration function is captured.
This allows the quick identification of timer event sources in a system.

Sample output:

# echo 1 > /proc/timer_stats
# cat /proc/timer_stats
Timer Stats Version: v0.1
Sample period: 4.010 s
  24,     0 swapper          hrtimer_stop_sched_tick (hrtimer_sched_tick)
  11,     0 swapper          sk_reset_timer (tcp_delack_timer)
   6,     0 swapper          hrtimer_stop_sched_tick (hrtimer_sched_tick)
   2,     1 swapper          queue_delayed_work_on (delayed_work_timer_fn)
  17,     0 swapper          hrtimer_restart_sched_tick (hrtimer_sched_tick)
   2,     1 swapper          queue_delayed_work_on (delayed_work_timer_fn)
   4,  2050 pcscd            do_nanosleep (hrtimer_wakeup)
   5,  4179 sshd             sk_reset_timer (tcp_write_timer)
   4,  2248 yum-updatesd     schedule_timeout (process_timeout)
  18,     0 swapper          hrtimer_restart_sched_tick (hrtimer_sched_tick)
   3,     0 swapper          sk_reset_timer (tcp_delack_timer)
   1,     1 swapper          neigh_table_init_no_netlink (neigh_periodic_timer)
   2,     1 swapper          e1000_up (e1000_watchdog)
   1,     1 init             schedule_timeout (process_timeout)
100 total events, 25.24 events/sec

[ cleanups and hrtimers support from Thomas Gleixner <tglx@linutronix.de> ]
[bunk@stusta.de: nr_entries can become static]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 08:13:59 -08:00
David Woodhouse a304e1b828 [PATCH] Debug shared irqs
Drivers registering IRQ handlers with SA_SHIRQ really ought to be able to
handle an interrupt happening before request_irq() returns.  They also
ought to be able to handle an interrupt happening during the start of their
call to free_irq().  Let's test that hypothesis....

[bunk@stusta.de: Kconfig fixes]
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:28 -08:00
Robert P. J. Day b9b2a70037 [PATCH] Remove references to obsolete kernel config option DEBUG_RWSEMS
Remove the few references to the obsolete kernel config option
DEBUG_RWSEMS.

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 11:18:06 -08:00
Linus Torvalds d1526e2cda Remove stack unwinder for now
It has caused more problems than it ever really solved, and is
apparently not getting cleaned up and fixed.  We can put it back when
it's stable and isn't likely to make warning or bug events worse.

In the meantime, enable frame pointers for more readable stack traces.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-15 08:47:51 -08:00
Dave Jones 86327d19f7 Fix typo in new debug options.
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-12-12 20:16:36 +01:00
Don Mullis bf4735a46a [PATCH] Kconfig refactoring for better menu nesting
Refactor Kconfig content to maximize nesting of menus by menuconfig and
xconfig.

Tested by simultaneously running `make xconfig` with and without
patch, and comparing displays.

Signed-off-by: Don Mullis <dwm@meer.net>
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-10 09:55:39 -08:00
Andrew Morton 83ba254688 [PATCH] fault-injection: stacktrace filtering kconfig fix
`select' doesn't work very well.  With alpha `make allmodconfig' we end up
with CONFIG_STACKTRACE enabled, so we end up with undefined save_stacktrace()
at link time.

Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Don Mullis <dwm@meer.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:29:03 -08:00
Andrew Morton 1ab8509a31 [PATCH] fault-injection Kconfig cleanup
- Fix some spelling and grammatical errors

- Make the Kconfig menu more conventional.  First you select
  fault-injection, then under that you select particular clients of it.

Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Don Mullis <dwm@meer.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:29:03 -08:00
Akinobu Mita 329409aeda [PATCH] fault injection: stacktrace filtering
This patch provides stacktrace filtering feature.

The stacktrace filter allows failing only for the caller you are
interested in.

For example someone may want to inject kmalloc() failures into
only e100 module. they want to inject not only direct kmalloc() call,
but also indirect allocation, too.

- e100_poll --> netif_receive_skb --> packet_rcv_spkt --> skb_clone
  --> kmem_cache_alloc

This patch enables to detect function calls like this by stacktrace
and inject failures. The script Documentaion/fault-injection/failmodule.sh
helps it.

The range of text section of loaded e100 is expected to be
[/sys/module/e100/sections/.text, /sys/module/e100/sections/.exit.text)

So failmodule.sh stores these values into /debug/failslab/address-start
and /debug/failslab/address-end. The maximum stacktrace depth is specified
by /debug/failslab/stacktrace-depth.

Please see the example that demonstrates how to inject slab allocation
failures only for a specific module
in Documentation/fault-injection/fault-injection.txt

[dwm@meer.net: reject failure if any caller lies within specified range]
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Don Mullis <dwm@meer.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:29:03 -08:00
Akinobu Mita c17bb49517 [PATCH] fault-injection capability for disk IO
This patch provides fault-injection capability for disk IO.

Boot option:

fail_make_request=<probability>,<interval>,<space>,<times>

	<interval> -- specifies the interval of failures.

	<probability> -- specifies how often it should fail in percent.

	<space> -- specifies the size of free space where disk IO can be issued
		   safely in bytes.

	<times> -- specifies how many times failures may happen at most.

Debugfs:

/debug/fail_make_request/interval
/debug/fail_make_request/probability
/debug/fail_make_request/specifies
/debug/fail_make_request/times

Example:

	fail_make_request=10,100,0,-1
	echo 1 > /sys/blocks/hda/hda1/make-it-fail

generic_make_request() on /dev/hda1 fails once per 10 times.

Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:29:02 -08:00
Akinobu Mita 933e312e73 [PATCH] fault-injection capability for alloc_pages()
This patch provides fault-injection capability for alloc_pages()

Boot option:

fail_page_alloc=<interval>,<probability>,<space>,<times>

	<interval> -- specifies the interval of failures.

	<probability> -- specifies how often it should fail in percent.

	<space> -- specifies the size of free space where memory can be
		   allocated safely in pages.

	<times> -- specifies how many times failures may happen at most.

Debugfs:

/debug/fail_page_alloc/interval
/debug/fail_page_alloc/probability
/debug/fail_page_alloc/specifies
/debug/fail_page_alloc/times
/debug/fail_page_alloc/ignore-gfp-highmem
/debug/fail_page_alloc/ignore-gfp-wait

Example:

	fail_page_alloc=10,100,0,-1

The page allocation (alloc_pages(), ...) fails once per 10 times.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:29:02 -08:00
Akinobu Mita 8a8b6502fb [PATCH] fault-injection capability for kmalloc
This patch provides fault-injection capability for kmalloc.

Boot option:

failslab=<interval>,<probability>,<space>,<times>

	<interval> -- specifies the interval of failures.

	<probability> -- specifies how often it should fail in percent.

	<space> -- specifies the size of free space where memory can be
		   allocated safely in bytes.

	<times> -- specifies how many times failures may happen at most.

Debugfs:

/debug/failslab/interval
/debug/failslab/probability
/debug/failslab/specifies
/debug/failslab/times
/debug/failslab/ignore-gfp-highmem
/debug/failslab/ignore-gfp-wait

Example:

	failslab=10,100,0,-1

slab allocation (kmalloc(), kmem_cache_alloc(),..) fails once per 10 times.

Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:29:02 -08:00
Akinobu Mita 6ff1cb355e [PATCH] fault-injection capabilities infrastructure
This patch provides base functions implement to fault-injection
capabilities.

- The function should_fail() is taken from failmalloc-1.0
  (http://www.nongnu.org/failmalloc/)

[akpm@osdl.org: cleanups, comments, add __init]
Cc: <okuji@enbug.org>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Don Mullis <dwm@meer.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:29:02 -08:00
Jeremy Fitzhardinge 91768d6c2b [PATCH] Generic BUG for i386
This makes i386 use the generic BUG machinery.  There are no functional
changes from the old i386 implementation.

The main advantage in using the generic BUG machinery for i386 is that the
inlined overhead of BUG is just the ud2a instruction; the file+line(+function)
information are no longer inlined into the instruction stream.  This reduces
cache pollution, and makes disassembly work properly.

Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Hugh Dickens <hugh@veritas.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:28:39 -08:00
Jeremy Fitzhardinge 7664c5a1da [PATCH] Generic BUG implementation
This patch adds common handling for kernel BUGs, for use by architectures as
they wish.  The code is derived from arch/powerpc.

The advantages of having common BUG handling are:
 - consistent BUG reporting across architectures
 - shared implementation of out-of-line file/line data
 - implement CONFIG_DEBUG_BUGVERBOSE consistently

This means that in inline impact of BUG is just the illegal instruction
itself, which is an improvement for i386 and x86-64.

A BUG is represented in the instruction stream as an illegal instruction,
which has file/line information associated with it.  This extra information is
stored in the __bug_table section in the ELF file.

When the kernel gets an illegal instruction, it first confirms it might
possibly be from a BUG (ie, in kernel mode, the right illegal instruction).
It then calls report_bug().  This searches __bug_table for a matching
instruction pointer, and if found, prints the corresponding file/line
information.  If report_bug() determines that it wasn't a BUG which caused the
trap, it returns BUG_TRAP_TYPE_NONE.

Some architectures (powerpc) implement WARN using the same mechanism; if the
illegal instruction was the result of a WARN, then report_bug(Q) returns
CONFIG_DEBUG_BUGVERBOSE; otherwise it returns BUG_TRAP_TYPE_BUG.

lib/bug.c keeps a list of loaded modules which can be searched for __bug_table
entries.  The architecture must call
module_bug_finalize()/module_bug_cleanup() from its corresponding
module_finalize/cleanup functions.

Unsetting CONFIG_DEBUG_BUGVERBOSE will reduce the kernel size by some amount.
At the very least, filename and line information will not be recorded for each
but, but architectures may decide to store no extra information per BUG at
all.

Unfortunately, gcc doesn't have a general way to mark an asm() as noreturn, so
architectures will generally have to include an infinite loop (or similar) in
the BUG code, so that gcc knows execution won't continue beyond that point.
gcc does have a __builtin_trap() operator which may be useful to achieve the
same effect, unfortunately it cannot be used to actually implement the BUG
itself, because there's no way to get the instruction's address for use in
generating the __bug_table entry.

[randy.dunlap@oracle.com: Handle BUG=n, GENERIC_BUG=n to prevent build errors]
[bunk@stusta.de: include/linux/bug.h must always #include <linux/module.h]
Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Andi Kleen <ak@muc.de>
Cc: Hugh Dickens <hugh@veritas.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:28:39 -08:00
Randy Dunlap d3b8b6e5f2 [PATCH] kconfig: PRINTK_TIME depends on PRINTK
Make PRINTK_TIME depend on PRINTK.  Only display/offer it if PRINTK is
enabled.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:33 -08:00
Kevin Hilman 75e31aaaf4 [ARM] 3909/1: Disable UWIND_INFO for ARM (again)
According to Daniel Jacobowitz, UNWIND_INFO is not useful on ARM, and
in fact doesn't even compile.

This patch disables the option for ARM.

Signed-off-by: Kevin Hilman <khilman@mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-10-28 10:15:31 +01:00
Al Viro 1b95817dd7 [PATCH] uml shouldn't do HEADERS_CHECK
The lack of asm-um/Kbuild is deliberate.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-13 08:35:38 -07:00
David Woodhouse 0f836e5fec [PATCH] Add CONFIG_HEADERS_CHECK option to automatically run 'make headers_check'
In order to encourage people to notice when they break the exported
headers, add a config option which automatically runs the sanity checks
when building vmlinux.  That way, those who use allyesconfig will notice
failures.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-11 11:14:21 -07:00
Heiko Carstens dea20a3fbd [PATCH] Disable DETECT_SOFTLOCKUP for s390
We got several false bug reports because of enabled
CONFIG_DETECT_SOFTLOCKUP.  Disable soft lockup detection on s390, since it
doesn't work on a virtualized architecture.

Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-11 11:14:14 -07:00
Ankita Garg 8bb31b9d53 [PATCH] Linux Kernel Dump Test Module
A simple module to test Linux Kernel Dump mechanism.  This module uses
jprobes to install/activate pre-defined crash points.  At different crash
points, various types of crashing scenarios are created like a BUG(),
panic(), exception, recursive loop and stack overflow.  The user can
activate a crash point with specific type by providing parameters at the
time of module insertion.  Please see the file header for usage
information.  The module is based on the Linux Kernel Dump Test Tool by
Fernando <http://lkdtt.sourceforge.net>.

This module could be merged with mainline. Jprobes is used here so that the
context in which crash point is hit, could be maintained. This implements
all the crash points as done by LKDTT except the one in the middle of
tasklet_action().

Signed-off-by: Ankita Garg <ankita@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02 07:57:16 -07:00
Dave Jones 199a9afc3d [PATCH] Debug variants of linked list macros
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:05 -07:00
Paul Mundt 49c3f807f5 sh: Enable verbose BUG() support.
Add SH to the list of platforms interested in Verbose BUG().

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2006-09-27 18:04:36 +09:00
Paul Mundt 2549b3222f sh: Use generic CONFIG_FRAME_POINTER.
We had our own version, which serves no purpose. Simply
hook SH in to the generic one.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2006-09-27 16:22:33 +09:00
Linus Torvalds b278240839 Merge branch 'for-linus' of git://one.firstfloor.org/home/andi/git/linux-2.6
* 'for-linus' of git://one.firstfloor.org/home/andi/git/linux-2.6: (225 commits)
  [PATCH] Don't set calgary iommu as default y
  [PATCH] i386/x86-64: New Intel feature flags
  [PATCH] x86: Add a cumulative thermal throttle event counter.
  [PATCH] i386: Make the jiffies compares use the 64bit safe macros.
  [PATCH] x86: Refactor thermal throttle processing
  [PATCH] Add 64bit jiffies compares (for use with get_jiffies_64)
  [PATCH] Fix unwinder warning in traps.c
  [PATCH] x86: Allow disabling early pci scans with pci=noearly or disallowing conf1
  [PATCH] x86: Move direct PCI scanning functions out of line
  [PATCH] i386/x86-64: Make all early PCI scans dependent on CONFIG_PCI
  [PATCH] Don't leak NT bit into next task
  [PATCH] i386/x86-64: Work around gcc bug with noreturn functions in unwinder
  [PATCH] Fix some broken white space in ia32_signal.c
  [PATCH] Initialize argument registers for 32bit signal handlers.
  [PATCH] Remove all traces of signal number conversion
  [PATCH] Don't synchronize time reading on single core AMD systems
  [PATCH] Remove outdated comment in x86-64 mmconfig code
  [PATCH] Use string instructions for Core2 copy/clear
  [PATCH] x86: - restore i8259A eoi status on resume
  [PATCH] i386: Split multi-line printk in oops output.
  ...
2006-09-26 13:07:55 -07:00
Linus Torvalds dd77a4ee0f Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6: (47 commits)
  Driver core: Don't call put methods while holding a spinlock
  Driver core: Remove unneeded routines from driver core
  Driver core: Fix potential deadlock in driver core
  PCI: enable driver multi-threaded probe
  Driver Core: add ability for drivers to do a threaded probe
  sysfs: add proper sysfs_init() prototype
  drivers/base: check errors
  drivers/base: Platform notify needs to occur before drivers attach to the device
  v4l-dev2: handle __must_check
  add CONFIG_ENABLE_MUST_CHECK
  add __must_check to device management code
  Driver core: fixed add_bind_files() definition
  Driver core: fix comments in drivers/base/power/resume.c
  sysfs_remove_bin_file: no return value, dump_stack on error
  kobject: must_check fixes
  Driver core: add ability for devices to create and remove bin files
  Class: add support for class interfaces for devices
  Driver core: create devices/virtual/ tree
  Driver core: add device_rename function
  Driver core: add ability for classes to handle devices properly
  ...
2006-09-26 11:49:46 -07:00
Haavard Skinnemoen 5f97f7f940 [PATCH] avr32 architecture
This adds support for the Atmel AVR32 architecture as well as the AT32AP7000
CPU and the AT32STK1000 development board.

AVR32 is a new high-performance 32-bit RISC microprocessor core, designed for
cost-sensitive embedded applications, with particular emphasis on low power
consumption and high code density.  The AVR32 architecture is not binary
compatible with earlier 8-bit AVR architectures.

The AVR32 architecture, including the instruction set, is described by the
AVR32 Architecture Manual, available from

http://www.atmel.com/dyn/resources/prod_documents/doc32000.pdf

The Atmel AT32AP7000 is the first CPU implementing the AVR32 architecture.  It
features a 7-stage pipeline, 16KB instruction and data caches and a full
Memory Management Unit.  It also comes with a large set of integrated
peripherals, many of which are shared with the AT91 ARM-based controllers from
Atmel.

Full data sheet is available from

http://www.atmel.com/dyn/resources/prod_documents/doc32003.pdf

while the CPU core implementation including caches and MMU is documented by
the AVR32 AP Technical Reference, available from

http://www.atmel.com/dyn/resources/prod_documents/doc32001.pdf

Information about the AT32STK1000 development board can be found at

http://www.atmel.com/dyn/products/tools_card.asp?tool_id=3918

including a BSP CD image with an earlier version of this patch, development
tools (binaries and source/patches) and a root filesystem image suitable for
booting from SD card.

Alternatively, there's a preliminary "getting started" guide available at
http://avr32linux.org/twiki/bin/view/Main/GettingStarted which provides links
to the sources and patches you will need in order to set up a cross-compiling
environment for avr32-linux.

This patch, as well as the other patches included with the BSP and the
toolchain patches, is actively supported by Atmel Corporation.

[dmccr@us.ibm.com: Fix more pxx_page macro locations]
[bunk@stusta.de: fix `make defconfig']
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Dave McCracken <dmccr@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:54 -07:00
Andi Kleen 3b8d1fe0f2 [PATCH] Don't force frame pointers for lockdep
Now that stacktrace supports dwarf2 don't force frame pointers for lockdep anymore

Cc: mingo@elte.hu
Signed-off-by: Andi Kleen <ak@suse.de>
2006-09-26 10:52:34 +02:00
Andrew Morton cebc04ba9a add CONFIG_ENABLE_MUST_CHECK
Those 1500 warnings can be a bit of a pain.  Add a config option to shut them
up.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-25 21:08:39 -07:00
Adrian Bunk 517e7aa5b0 [PATCH] let the the lockdep options depend on DEBUG_KERNEL
The lockdep options should depend on DEBUG_KERNEL since:
- they are kernel debugging options and
- they do otherwise break the DEBUG_KERNEL menu structure

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-14 21:53:55 -07:00
Ingo Molnar 4d9f34ad36 [PATCH] lockdep: kconfig
Offer the following lock validation options:

 CONFIG_PROVE_LOCKING

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:04 -07:00
Ingo Molnar fbb9ce9530 [PATCH] lockdep: core
Do 'make oldconfig' and accept all the defaults for new config options -
reboot into the kernel and if everything goes well it should boot up fine and
you should have /proc/lockdep and /proc/lockdep_stats files.

Typically if the lock validator finds some problem it will print out
voluminous debug output that begins with "BUG: ..." and which syslog output
can be used by kernel developers to figure out the precise locking scenario.

What does the lock validator do?  It "observes" and maps all locking rules as
they occur dynamically (as triggered by the kernel's natural use of spinlocks,
rwlocks, mutexes and rwsems).  Whenever the lock validator subsystem detects a
new locking scenario, it validates this new rule against the existing set of
rules.  If this new rule is consistent with the existing set of rules then the
new rule is added transparently and the kernel continues as normal.  If the
new rule could create a deadlock scenario then this condition is printed out.

When determining validity of locking, all possible "deadlock scenarios" are
considered: assuming arbitrary number of CPUs, arbitrary irq context and task
context constellations, running arbitrary combinations of all the existing
locking scenarios.  In a typical system this means millions of separate
scenarios.  This is why we call it a "locking correctness" validator - for all
rules that are observed the lock validator proves it with mathematical
certainty that a deadlock could not occur (assuming that the lock validator
implementation itself is correct and its internal data structures are not
corrupted by some other kernel subsystem).  [see more details and conditionals
of this statement in include/linux/lockdep.h and
Documentation/lockdep-design.txt]

Furthermore, this "all possible scenarios" property of the validator also
enables the finding of complex, highly unlikely multi-CPU multi-context races
via single single-context rules, increasing the likelyhood of finding bugs
drastically.  In practical terms: the lock validator already found a bug in
the upstream kernel that could only occur on systems with 3 or more CPUs, and
which needed 3 very unlikely code sequences to occur at once on the 3 CPUs.
That bug was found and reported on a single-CPU system (!).  So in essence a
race will be found "piecemail-wise", triggering all the necessary components
for the race, without having to reproduce the race scenario itself!  In its
short existence the lock validator found and reported many bugs before they
actually caused a real deadlock.

To further increase the efficiency of the validator, the mapping is not per
"lock instance", but per "lock-class".  For example, all struct inode objects
in the kernel have inode->inotify_mutex.  If there are 10,000 inodes cached,
then there are 10,000 lock objects.  But ->inotify_mutex is a single "lock
type", and all locking activities that occur against ->inotify_mutex are
"unified" into this single lock-class.  The advantage of the lock-class
approach is that all historical ->inotify_mutex uses are mapped into a single
(and as narrow as possible) set of locking rules - regardless of how many
different tasks or inode structures it took to build this set of rules.  The
set of rules persist during the lifetime of the kernel.

To see the rough magnitude of checking that the lock validator does, here's a
portion of /proc/lockdep_stats, fresh after bootup:

 lock-classes:                            694 [max: 2048]
 direct dependencies:                  1598 [max: 8192]
 indirect dependencies:               17896
 all direct dependencies:             16206
 dependency chains:                    1910 [max: 8192]
 in-hardirq chains:                      17
 in-softirq chains:                     105
 in-process chains:                    1065
 stack-trace entries:                 38761 [max: 131072]
 combined max dependencies:         2033928
 hardirq-safe locks:                     24
 hardirq-unsafe locks:                  176
 softirq-safe locks:                     53
 softirq-unsafe locks:                  137
 irq-safe locks:                         59
 irq-unsafe locks:                      176

The lock validator has observed 1598 actual single-thread locking patterns,
and has validated all possible 2033928 distinct locking scenarios.

More details about the design of the lock validator can be found in
Documentation/lockdep-design.txt, which can also found at:

   http://redhat.com/~mingo/lockdep-patches/lockdep-design.txt

[bunk@stusta.de: cleanups]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:03 -07:00
Ingo Molnar cae2ed9aa5 [PATCH] lockdep: locking API self tests
Introduce DEBUG_LOCKING_API_SELFTESTS, which uses the generic lock debugging
code's silent-failure feature to run a matrix of testcases.  There are 210
testcases currently:

  +-----------------------
  | Locking API testsuite:
  +------------------------------+------+------+------+------+------+------+
                                 | spin |wlock |rlock |mutex | wsem | rsem |
  -------------------------------+------+------+------+------+------+------+
                     A-A deadlock:  ok  |  ok  |  ok  |  ok  |  ok  |  ok  |
                 A-B-B-A deadlock:  ok  |  ok  |  ok  |  ok  |  ok  |  ok  |
             A-B-B-C-C-A deadlock:  ok  |  ok  |  ok  |  ok  |  ok  |  ok  |
             A-B-C-A-B-C deadlock:  ok  |  ok  |  ok  |  ok  |  ok  |  ok  |
         A-B-B-C-C-D-D-A deadlock:  ok  |  ok  |  ok  |  ok  |  ok  |  ok  |
         A-B-C-D-B-D-D-A deadlock:  ok  |  ok  |  ok  |  ok  |  ok  |  ok  |
         A-B-C-D-B-C-D-A deadlock:  ok  |  ok  |  ok  |  ok  |  ok  |  ok  |
                    double unlock:  ok  |  ok  |  ok  |  ok  |  ok  |  ok  |
                 bad unlock order:  ok  |  ok  |  ok  |  ok  |  ok  |  ok  |
  --------------------------------------+------+------+------+------+------+
              recursive read-lock:             |  ok  |             |  ok  |
  --------------------------------------+------+------+------+------+------+
                non-nested unlock:  ok  |  ok  |  ok  |  ok  |
  --------------------------------------+------+------+------+
     hard-irqs-on + irq-safe-A/12:  ok  |  ok  |  ok  |
     soft-irqs-on + irq-safe-A/12:  ok  |  ok  |  ok  |
     hard-irqs-on + irq-safe-A/21:  ok  |  ok  |  ok  |
     soft-irqs-on + irq-safe-A/21:  ok  |  ok  |  ok  |
       sirq-safe-A => hirqs-on/12:  ok  |  ok  |  ok  |
       sirq-safe-A => hirqs-on/21:  ok  |  ok  |  ok  |
         hard-safe-A + irqs-on/12:  ok  |  ok  |  ok  |
         soft-safe-A + irqs-on/12:  ok  |  ok  |  ok  |
         hard-safe-A + irqs-on/21:  ok  |  ok  |  ok  |
         soft-safe-A + irqs-on/21:  ok  |  ok  |  ok  |
    hard-safe-A + unsafe-B #1/123:  ok  |  ok  |  ok  |
    soft-safe-A + unsafe-B #1/123:  ok  |  ok  |  ok  |
    hard-safe-A + unsafe-B #1/132:  ok  |  ok  |  ok  |
    soft-safe-A + unsafe-B #1/132:  ok  |  ok  |  ok  |
    hard-safe-A + unsafe-B #1/213:  ok  |  ok  |  ok  |
    soft-safe-A + unsafe-B #1/213:  ok  |  ok  |  ok  |
    hard-safe-A + unsafe-B #1/231:  ok  |  ok  |  ok  |
    soft-safe-A + unsafe-B #1/231:  ok  |  ok  |  ok  |
    hard-safe-A + unsafe-B #1/312:  ok  |  ok  |  ok  |
    soft-safe-A + unsafe-B #1/312:  ok  |  ok  |  ok  |
    hard-safe-A + unsafe-B #1/321:  ok  |  ok  |  ok  |
    soft-safe-A + unsafe-B #1/321:  ok  |  ok  |  ok  |
    hard-safe-A + unsafe-B #2/123:  ok  |  ok  |  ok  |
    soft-safe-A + unsafe-B #2/123:  ok  |  ok  |  ok  |
    hard-safe-A + unsafe-B #2/132:  ok  |  ok  |  ok  |
    soft-safe-A + unsafe-B #2/132:  ok  |  ok  |  ok  |
    hard-safe-A + unsafe-B #2/213:  ok  |  ok  |  ok  |
    soft-safe-A + unsafe-B #2/213:  ok  |  ok  |  ok  |
    hard-safe-A + unsafe-B #2/231:  ok  |  ok  |  ok  |
    soft-safe-A + unsafe-B #2/231:  ok  |  ok  |  ok  |
    hard-safe-A + unsafe-B #2/312:  ok  |  ok  |  ok  |
    soft-safe-A + unsafe-B #2/312:  ok  |  ok  |  ok  |
    hard-safe-A + unsafe-B #2/321:  ok  |  ok  |  ok  |
    soft-safe-A + unsafe-B #2/321:  ok  |  ok  |  ok  |
      hard-irq lock-inversion/123:  ok  |  ok  |  ok  |
      soft-irq lock-inversion/123:  ok  |  ok  |  ok  |
      hard-irq lock-inversion/132:  ok  |  ok  |  ok  |
      soft-irq lock-inversion/132:  ok  |  ok  |  ok  |
      hard-irq lock-inversion/213:  ok  |  ok  |  ok  |
      soft-irq lock-inversion/213:  ok  |  ok  |  ok  |
      hard-irq lock-inversion/231:  ok  |  ok  |  ok  |
      soft-irq lock-inversion/231:  ok  |  ok  |  ok  |
      hard-irq lock-inversion/312:  ok  |  ok  |  ok  |
      soft-irq lock-inversion/312:  ok  |  ok  |  ok  |
      hard-irq lock-inversion/321:  ok  |  ok  |  ok  |
      soft-irq lock-inversion/321:  ok  |  ok  |  ok  |
      hard-irq read-recursion/123:  ok  |
      soft-irq read-recursion/123:  ok  |
      hard-irq read-recursion/132:  ok  |
      soft-irq read-recursion/132:  ok  |
      hard-irq read-recursion/213:  ok  |
      soft-irq read-recursion/213:  ok  |
      hard-irq read-recursion/231:  ok  |
      soft-irq read-recursion/231:  ok  |
      hard-irq read-recursion/312:  ok  |
      soft-irq read-recursion/312:  ok  |
      hard-irq read-recursion/321:  ok  |
      soft-irq read-recursion/321:  ok  |
  --------------------------------+-----+----------------
  Good, all 210 testcases passed! |
  --------------------------------+

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:03 -07:00
Heiko Carstens cbbd1fa72d [PATCH] lockdep: s390 CONFIG_FRAME_POINTER support
CONFIG_FRAME_POINTER support for s390.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:02 -07:00
Ingo Molnar 8637c09901 [PATCH] lockdep: stacktrace subsystem, core
Framework to generate and save stacktraces quickly, without printing anything
to the console.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:02 -07:00
Ingo Molnar fb7e42413a [PATCH] lockdep: remove mutex deadlock checking code
With the lock validator we detect mutex deadlocks (and more), the mutex
deadlock checking code is both redundant and slower.  So remove it.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:01 -07:00
Arjan van de Ven f71d20e961 [PATCH] Add EXPORT_UNUSED_SYMBOL and EXPORT_UNUSED_SYMBOL_GPL
Temporarily add EXPORT_UNUSED_SYMBOL and EXPORT_UNUSED_SYMBOL_GPL.  These
will be used as a transition measure for symbols that aren't used in the
kernel and are on the way out.  When a module uses such a symbol, a warning
is printk'd at modprobe time.

The main reason for removing unused exports is size: eacho export takes
roughly between 100 and 150 bytes of kernel space in the binary.  This
patch gives users the option to immediately get this size gain via a config
option.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-28 14:59:04 -07:00
Roman Zippel a1583d3e83 [PATCH] fix rt-mutex defaults and dependencies
Fix defaults and dependencies.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:47 -07:00
Thomas Gleixner 61a8712286 [PATCH] pi-futex: rt mutex tester
RT-mutex tester: scriptable tester for rt mutexes, which allows userspace
scripting of mutex unit-tests (and dynamic tests as well), using the actual
rt-mutex implementation of the kernel.

[akpm@osdl.org: fixlet]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:47 -07:00
Ingo Molnar e7eebaf6a8 [PATCH] pi-futex: rt mutex debug
Runtime debugging functionality for rt-mutexes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 17:32:47 -07:00
Jan Beulich 176a2718f4 [PATCH] i386: reliable stack trace support (i386)
These are the i386-specific pieces to enable reliable stack traces. This is
going to be even more useful once CFI annotations get added to he assembly
code, namely to entry.S.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 10:48:17 -07:00
Jan Beulich b538ed278b [PATCH] x86_64: reliable stack trace support (x86-64)
These are the x86_64-specific pieces to enable reliable stack traces. The
only restriction with this is that it currently cannot unwind across the
interrupt->normal stack boundary, as that transition is lacking proper
annotation.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 10:48:17 -07:00
Jan Beulich 4552d5dc08 [PATCH] x86_64: reliable stack trace support
These are the generic bits needed to enable reliable stack traces based
on Dwarf2-like (.eh_frame) unwind information. Subsequent patches will
enable x86-64 and i386 to make use of this.

Thanks to Andi Kleen and Ingo Molnar, who pointed out several possibilities
for improvement.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 10:48:17 -07:00
David S. Miller 06a1be167e [SPARC]: Handle UNWIND_INFO properly.
For sparc32 we need R_SPARC_UA32 relocation support, for
sparc64 we need the handle R_SPARC_DISP32 relocations.

Based upon reports and initial patch by Martin Habets.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-05-12 12:45:50 -07:00
Tim Chen cca57c5b5a [PATCH] Kconfig.debug: Set DEBUG_MUTEX to off by default
DEBUG_MUTEX flag is on by default in current kernel configuration.

During performance testing, we saw mutex debug functions like
mutex_debug_check_no_locks_freed (called by kfree()) is expensive as it
goes through a global list of memory areas with mutex lock and do the
checking.  For benchmarks such as Volanomark and Hackbench, we have seen
more than 40% drop in performance on some platforms.  We suggest to set
DEBUG_MUTEX off by default.  Or at least do that later when we feel that
the mutex changes in the current code have stabilized.

Signed-off-by: Tim Chen <tim.c.chen@intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-19 09:13:51 -07:00
Helge Deller a41d3862df [PARISC] Remove obsolete CONFIG_DEBUG_IOREMAP
Remove CONFIG_DEBUG_IOREMAP, it's now obsolete and won't work anyway.
Remove it from lib/KConfig since it was only available on parisc.

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:50 +00:00
Jens Axboe ae36b883d2 [PATCH] Don't make debugfs depend on DEBUG_KERNEL
We use it generally now, at least blktrace isn't a specific debug
kernel feature.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-03-27 09:29:03 +02:00
Andi Kleen 6a0f03e0d3 [PATCH] x86_64: Don't enable CONFIG_UNWIND_INFO by default for DEBUG_KERNEL
DEBUG_KERNEL is often enabled just for sysrq, but this doesn't
mean the user wants more heavyweight debugging information.

Cc: jbeulich@novell.com

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 09:14:39 -08:00
Andrew Morton 4a2f0acf0f [PATCH] kconfig: clarify memory debug options
The Kconfig text for CONFIG_DEBUG_SLAB and CONFIG_DEBUG_PAGEALLOC have always
seemed a bit confusing.  Change them to:

CONFIG_DEBUG_SLAB: "Debug slab memory allocations"
CONFIG_DEBUG_PAGEALLOC: "Debug page memory allocations"

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:22:54 -08:00
Al Viro 871751e25d [PATCH] slab: implement /proc/slab_allocators
Implement /proc/slab_allocators.   It produces output like:

idr_layer_cache: 80 idr_pre_get+0x33/0x4e
buffer_head: 2555 alloc_buffer_head+0x20/0x75
mm_struct: 9 mm_alloc+0x1e/0x42
mm_struct: 20 dup_mm+0x36/0x370
vm_area_struct: 384 dup_mm+0x18f/0x370
vm_area_struct: 151 do_mmap_pgoff+0x2e0/0x7c3
vm_area_struct: 1 split_vma+0x5a/0x10e
vm_area_struct: 11 do_brk+0x206/0x2e2
vm_area_struct: 2 copy_vma+0xda/0x142
vm_area_struct: 9 setup_arg_pages+0x99/0x214
fs_cache: 8 copy_fs_struct+0x21/0x133
fs_cache: 29 copy_process+0xf38/0x10e3
files_cache: 30 alloc_files+0x1b/0xcf
signal_cache: 81 copy_process+0xbaa/0x10e3
sighand_cache: 77 copy_process+0xe65/0x10e3
sighand_cache: 1 de_thread+0x4d/0x5f8
anon_vma: 241 anon_vma_prepare+0xd9/0xf3
size-2048: 1 add_sect_attrs+0x5f/0x145
size-2048: 2 journal_init_revoke+0x99/0x302
size-2048: 2 journal_init_revoke+0x137/0x302
size-2048: 2 journal_init_inode+0xf9/0x1c4

Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Alexander Nyberg <alexn@telia.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Cc: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
DESC
slab-leaks3-locking-fix
EDESC
From: Andrew Morton <akpm@osdl.org>

Update for slab-remove-cachep-spinlock.patch

Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Alexander Nyberg <alexn@telia.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Cc: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:22:49 -08:00
Jan Beulich 604bf5a216 [PATCH] CONFIG_UNWIND_INFO
As a foundation for reliable stack unwinding, this adds a config option
(available to all architectures except IA64 and those where the module
loader might have problems with the resulting relocations) to enable the
generation of frame unwind information.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Paul Mundt <lethal@linux-sh.org>,
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-24 07:33:25 -08:00
Ingo Molnar a9df3d0f31 [PATCH] When CONFIG_CC_OPTIMIZE_FOR_SIZE, allow gcc4 to control inlining
If optimizing for size (CONFIG_CC_OPTIMIZE_FOR_SIZE), allow gcc4 compilers
to decide what to inline and what not - instead of the kernel forcing gcc
to inline all the time.  This requires several places that require to be
inlined to be marked as such, previous patches in this series do that.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:16 -08:00
Adrian Bunk f346f4b373 [PATCH] let MAGIC_SYSRQ no longer depend on DEBUG_KERNEL
I know several people using MAGIC_SYSRQ not for kernel debugging but for
trying to do a halfway normal shutdown in case of problems.

Since there's no technical reason why MAGIC_SYSRQ would have to depend on
DEBUG_KERNEL, I'm therefore suggesting to drop this dependency.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 08:02:02 -08:00
Ingo Molnar 408894ee4d [PATCH] mutex subsystem, debugging code
mutex implementation - add debugging code.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
2006-01-09 15:59:20 -08:00
Ingo Molnar 50dd26ba09 [PATCH] DEBUG_SLAB depends on SLAB
Make DEBUG_SLAB depend on SLAB.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:41 -08:00
Martin Schwidefsky 347a8dc3b8 [PATCH] s390: cleanup Kconfig
Sanitize some s390 Kconfig options.  We have ARCH_S390, ARCH_S390X,
ARCH_S390_31, 64BIT, S390_SUPPORT and COMPAT.  Replace these 6 options by
S390, 64BIT and COMPAT.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:53 -08:00
Nick Piggin 13e7444b0e [PATCH] mm: remove bad_range
bad_range is supposed to be a temporary check.  It would be a pity to throw it
out.  Make it depend on CONFIG_DEBUG_VM instead.

CONFIG_HOLES_IN_ZONE systems were relying on this to check pfn_valid in the
page allocator.  Add that to page_is_buddy instead.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:25 -08:00
Paul E. McKenney a241ec65ae [PATCH] RCU torture-testing kernel module
This patch is a rewrite of the one submitted on October 1st, using modules
(http://marc.theaimsgroup.com/?l=linux-kernel&m=112819093522998&w=2).

This rewrite adds a tristate CONFIG_RCU_TORTURE_TEST, which enables an
intense torture test of the RCU infratructure.  This is needed due to the
continued changes to the RCU infrastructure to accommodate dynamic ticks,
CPU hotplug, realtime, and so on.  Most of the code is in a separate file
that is compiled only if the CONFIG variable is set.  Documentation on how
to run the test and interpret the output is also included.

This code has been tested on i386 and ppc64, and an earlier version of the
code has received extensive testing on a number of architectures as part of
the PREEMPT_RT patchset.

Signed-off-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:27 -08:00
Jesper Juhl 2a38bccd0c [PATCH] Kconfig help text correction for CONFIG_FRAME_POINTER
Fix-up the CONFIG_FRAME_POINTER help text language a bit.

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:24 -08:00
Brian Gerst 0d078f6f96 [PATCH] CONFIG_IA32
Add CONFIG_X86_32 for i386.  This allows selecting options that only apply
to 32-bit systems.

(X86 && !X86_64) becomes X86_32
(X86 ||  X86_64) becomes X86

Signed-off-by: Brian Gerst <bgerst@didntduck.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:10 -08:00
Andi Kleen aeb39986ec [PATCH] x86-64: Allow frame pointer and fix help text.
Allow frame pointer and fix help text.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-12 10:50:58 -07:00
Ingo Molnar 8446f1d391 [PATCH] detect soft lockups
This patch adds a new kernel debug feature: CONFIG_DETECT_SOFTLOCKUP.

When enabled then per-CPU watchdog threads are started, which try to run
once per second.  If they get delayed for more than 10 seconds then a
callback from the timer interrupt detects this condition and prints out a
warning message and a stack dump (once per lockup incident).  The feature
is otherwise non-intrusive, it doesnt try to unlock the box in any way, it
only gets the debug info out, automatically, and on all CPUs affected by
the lockup.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-Off-By: Matthias Urlichs <smurf@smurf.noris.de>
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:17 -07:00
Adrian Bunk 3348e05a4f [PATCH] DEBUG_FS must depend on SYSFS
CONFIG_DEBUG_FS=y and CONFIG_SYSFS=n results in the following compile
error:

<--  snip  -->

...
  LD      vmlinux
fs/built-in.o: In function `debugfs_init':
inode.c:(.init.text+0x31be): undefined reference to `kernel_subsys'
make: *** [vmlinux] Error 1

<--  snip  -->

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-29 13:12:49 -07:00
Paolo 'Blaisorblade' Giarrusso 37fce857be [PATCH] uml: split CONFIG_FRAME_POINTER from DEBUG_INFO
Until now, FRAME_POINTER was set = DEBUG_INFO for UML.  Change it to be the
default way, so that it can be enabled alone (for instance to get better
backtraces on crashes).  The call-trace dumper which uses the frame pointer is
not yet in, I'm going to introduce it in a separate patch.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-28 16:46:13 -07:00
Matt Mackall c8538a7aa5 [PATCH] remove all kernel BUGs
This patch eliminates all kernel BUGs, trims about 35k off the typical
kernel, and makes the system slightly faster.

Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:59:01 -07:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00