Commit graph

358 commits

Author SHA1 Message Date
Linus Torvalds
7f9dce3837 Merge branch 'sched/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: hrtick_enabled() should use cpu_active()
  sched, x86: clean up hrtick implementation
  sched: fix build error, provide partition_sched_domains() unconditionally
  sched: fix warning in inc_rt_tasks() to not declare variable 'rq' if it's not needed
  cpu hotplug: Make cpu_active_map synchronization dependency clear
  cpu hotplug, sched: Introduce cpu_active_map and redo sched domain managment (take 2)
  sched: rework of "prioritize non-migratable tasks over migratable ones"
  sched: reduce stack size in isolated_cpu_setup()
  Revert parts of "ftrace: do not trace scheduler functions"

Fixed up conflicts in include/asm-x86/thread_info.h (due to the
TIF_SINGLESTEP unification vs TIF_HRTICK_RESCHED removal) and
kernel/sched_fair.c (due to cpu_active_map vs for_each_cpu_mask_nr()
introduction).
2008-07-23 19:36:53 -07:00
Johannes Berg
baabaae981 make CONFIG_KMOD invisible
... as preparation for removing it completely, make it an
invisible bool defaulting to yes.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-22 19:24:28 +10:00
Denys Vlasenko
f7f5b67557 Shrink struct module: CONFIG_UNUSED_SYMBOLS ifdefs
module.c and module.h conatains code for finding
exported symbols which are declared with EXPORT_UNUSED_SYMBOL,
and this code is compiled in even if CONFIG_UNUSED_SYMBOLS is not set
and thus there can be no EXPORT_UNUSED_SYMBOLs in modules anyway
(because EXPORT_UNUSED_SYMBOL(x) are compiled out to nothing then).

This patch adds required #ifdefs.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-22 19:24:27 +10:00
Geert Uytterhoeven
fb6624ebd9 initrd: Fix virtual/physical mix-up in overwrite test
On recent kernels, I get the following error when using an initrd:

| initrd overwritten (0x00b78000 < 0x07668000) - disabling it.

My Amiga 4000 has 12 MiB of RAM at physical address 0x07400000 (virtual
0x00000000).
The initrd is located at the end of RAM: 0x00b78000 - 0x00c00000 (virtual).
The overwrite test compares the (virtual) initrd location to the (physical)
first available memory location, which fails.

This patch converts initrd_start to a page frame number, so it can safely be
compared with min_low_pfn.

Before the introduction of discontiguous memory support on m68k
(12d810c1b8), min_low_pfn was just left
untouched by the m68k-specific code (zero, I guess), and everything worked
fine.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-20 17:24:40 -07:00
Max Krasnyansky
e761b77252 cpu hotplug, sched: Introduce cpu_active_map and redo sched domain managment (take 2)
This is based on Linus' idea of creating cpu_active_map that prevents
scheduler load balancer from migrating tasks to the cpu that is going
down.

It allows us to simplify domain management code and avoid unecessary
domain rebuilds during cpu hotplug event handling.

Please ignore the cpusets part for now. It needs some more work in order
to avoid crazy lock nesting. Although I did simplfy and unify domain
reinitialization logic. We now simply call partition_sched_domains() in
all the cases. This means that we're using exact same code paths as in
cpusets case and hence the test below cover cpusets too.
Cpuset changes to make rebuild_sched_domains() callable from various
contexts are in the separate patch (right next after this one).

This not only boots but also easily handles
	while true; do make clean; make -j 8; done
and
	while true; do on-off-cpu 1; done
at the same time.
(on-off-cpu 1 simple does echo 0/1 > /sys/.../cpu1/online thing).

Suprisingly the box (dual-core Core2) is quite usable. In fact I'm typing
this on right now in gnome-terminal and things are moving just fine.

Also this is running with most of the debug features enabled (lockdep,
mutex, etc) no BUG_ONs or lockdep complaints so far.

I believe I addressed all of the Dmitry's comments for original Linus'
version. I changed both fair and rt balancer to mask out non-active cpus.
And replaced cpu_is_offline() with !cpu_active() in the main scheduler
code where it made sense (to me).

Signed-off-by: Max Krasnyanskiy <maxk@qualcomm.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Gregory Haskins <ghaskins@novell.com>
Cc: dmitry.adamushko@gmail.com
Cc: pj@sgi.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 13:22:25 +02:00
Linus Torvalds
9c1be0c471 Merge branch 'for_linus' of git://git.infradead.org/~dedekind/ubifs-2.6
* 'for_linus' of git://git.infradead.org/~dedekind/ubifs-2.6:
  UBIFS: include to compilation
  UBIFS: add new flash file system
  UBIFS: add brief documentation
  MAINTAINERS: add UBIFS section
  do_mounts: allow UBI root device name
  VFS: export sync_sb_inodes
  VFS: move inode_lock into sync_sb_inodes
2008-07-16 15:02:57 -07:00
Linus Torvalds
59190f4213 Merge branch 'generic-ipi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'generic-ipi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (22 commits)
  generic-ipi: more merge fallout
  generic-ipi: merge fix
  x86, visws: use mach-default/entry_arch.h
  x86, visws: fix generic-ipi build
  generic-ipi: fixlet
  generic-ipi: fix s390 build bug
  generic-ipi: fix linux-next tree build failure
  fix: "smp_call_function: get rid of the unused nonatomic/retry argument"
  fix: "smp_call_function: get rid of the unused nonatomic/retry argument"
  fix "smp_call_function: get rid of the unused nonatomic/retry argument"
  on_each_cpu(): kill unused 'retry' parameter
  smp_call_function: get rid of the unused nonatomic/retry argument
  sh: convert to generic helpers for IPI function calls
  parisc: convert to generic helpers for IPI function calls
  mips: convert to generic helpers for IPI function calls
  m32r: convert to generic helpers for IPI function calls
  arm: convert to generic helpers for IPI function calls
  alpha: convert to generic helpers for IPI function calls
  ia64: convert to generic helpers for IPI function calls
  powerpc: convert to generic helpers for IPI function calls
  ...

Fix trivial conflicts due to rcu updates in kernel/rcupdate.c manually
2008-07-15 14:12:03 -07:00
Ingo Molnar
1a781a777b Merge branch 'generic-ipi' into generic-ipi-for-linus
Conflicts:

	arch/powerpc/Kconfig
	arch/s390/kernel/time.c
	arch/x86/kernel/apic_32.c
	arch/x86/kernel/cpu/perfctr-watchdog.c
	arch/x86/kernel/i8259_64.c
	arch/x86/kernel/ldt.c
	arch/x86/kernel/nmi_64.c
	arch/x86/kernel/smpboot.c
	arch/x86/xen/smp.c
	include/asm-x86/hw_irq_32.h
	include/asm-x86/hw_irq_64.h
	include/asm-x86/mach-default/irq_vectors.h
	include/asm-x86/mach-voyager/irq_vectors.h
	include/asm-x86/smp.h
	kernel/Makefile

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-15 21:55:59 +02:00
Ingo Molnar
6c9fcaf2ee Merge branch 'core/rcu' into core/rcu-for-linus 2008-07-15 21:10:12 +02:00
Adrian Hunter
2d62f48858 do_mounts: allow UBI root device name
Similarly to MTD devices, allow UBI devices.

Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
2008-07-14 19:10:52 +03:00
Jens Axboe
3d44223327 Add generic helpers for arch IPI function calls
This adds kernel/smp.c which contains helpers for IPI function calls. In
addition to supporting the existing smp_call_function() in a more efficient
manner, it also adds a more scalable variant called smp_call_function_single()
for calling a given function on a single CPU only.

The core of this is based on the x86-64 patch from Nick Piggin, lots of
changes since then. "Alan D. Brunelle" <Alan.Brunelle@hp.com> has
contributed lots of fixes and suggestions as well. Also thanks to
Paul E. McKenney <paulmck@linux.vnet.ibm.com> for reviewing RCU usage
and getting rid of the data allocation fallback deadlock.

Acked-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-06-26 11:21:34 +02:00
Alok Kataria
f3f3149f35 x86: use cpu_khz for loops_per_jiffy calculation, cleanup
As suggested by Ingo, remove all references to tsc from init/calibrate.c

TSC is x86 specific, and using tsc in variable names in a generic file should
be avoided. lpj_tsc is now called lpj_fine, since it is related to fine tuning
of lpj value. Also tsc_rate_*  is called timer_rate_*

Signed-off-by: Alok N Kataria <akataria@vmware.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Daniel Hecht <dhecht@vmware.com>
Cc: Tim Mann <mann@vmware.com>
Cc: Zach Amsden <zach@vmware.com>
Cc: Sahil Rihan <srihan@vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-24 13:53:46 +02:00
Alok Kataria
3da757daf8 x86: use cpu_khz for loops_per_jiffy calculation
On the x86 platform we can use the value of tsc_khz computed during tsc
calibration to calculate the loops_per_jiffy value. Its very important
to keep the error in lpj values to minimum as any error in that may
result in kernel panic in check_timer. In virtualization environment, On
a highly overloaded host the guest delay calibration may sometimes
result in errors beyond the ~50% that timer_irq_works can handle,
resulting in the guest panicking.

Does some formating changes to lpj_setup code to now have a single
printk to print the bogomips value.

We do this only for the boot processor because the AP's can have
different base frequencies or the BIOS might boot a AP at a different
frequency.

Signed-off-by: Alok N Kataria <akataria@vmware.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Daniel Hecht <dhecht@vmware.com>
Cc: Tim Mann <mann@vmware.com>
Cc: Zach Amsden <zach@vmware.com>
Cc: Sahil Rihan <srihan@vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-23 22:51:33 +02:00
Ingo Molnar
766d02786e Merge branch 'linus' into core/rcu 2008-06-16 11:23:36 +02:00
Sam Ravnborg
73531905ed Kconfig: introduce ARCH_DEFCONFIG to DEFCONFIG_LIST
init/Kconfig contains a list of configs that are searched
for if 'make *config' are used with no .config present.
Extend this list to look at the config identified by
ARCH_DEFCONFIG.

With this change we now try the defconfig targets last.

This fixes a regression reported
by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
2008-05-25 23:03:18 +02:00
Adrian Bunk
03de250a26 md: proper extern for mdp_major
This patch adds a proper extern for mdp_major in include/linux/raid/md.h

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-24 09:56:09 -07:00
Paul E. McKenney
4446a36ff8 rcu: add call_rcu_sched()
Fourth cut of patch to provide the call_rcu_sched().  This is again to
synchronize_sched() as call_rcu() is to synchronize_rcu().

Should be fine for experimental and -rt use, but not ready for inclusion.
With some luck, I will be able to tell Andrew to come out of hiding on
the next round.

Passes multi-day rcutorture sessions with concurrent CPU hotplugging.

Fixes since the first version include a bug that could result in
indefinite blocking (spotted by Gautham Shenoy), better resiliency
against CPU-hotplug operations, and other minor fixes.

Fixes since the second version include reworking grace-period detection
to avoid deadlocks that could happen when running concurrently with
CPU hotplug, adding Mathieu's fix to avoid the softlockup messages,
as well as Mathieu's fix to allow use earlier in boot.

Fixes since the third version include a wrong-CPU bug spotted by
Andrew, getting rid of the obsolete synchronize_kernel API that somehow
snuck back in, merging spin_unlock() and local_irq_restore() in a
few places, commenting the code that checks for quiescent states based
on interrupting from user-mode execution or the idle loop, removing
some inline attributes, and some code-style changes.

Known/suspected shortcomings:

o	I still do not entirely trust the sleep/wakeup logic.  Next step
	will be to use a private snapshot of the CPU online mask in
	rcu_sched_grace_period() -- if the CPU wasn't there at the start
	of the grace period, we don't need to hear from it.  And the
	bit about accounting for changes in online CPUs inside of
	rcu_sched_grace_period() is ugly anyway.

o	It might be good for rcu_sched_grace_period() to invoke
	resched_cpu() when a given CPU wasn't responding quickly,
	but resched_cpu() is declared static...

This patch also fixes a long-standing bug in the earlier preemptable-RCU
implementation of synchronize_rcu() that could result in loss of
concurrent external changes to a task's CPU affinity mask.  I still cannot
remember who reported this...

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-19 10:01:36 +02:00
Cyrill Gorcunov
a76bfd0da2 initcalls: Fix m68k build and possible buffer overflow
This patch fixes a build bug on m68k - gcc decides to emit a call to the
strlen library function, which we don't implement.

More importantly - my previous patch "init: don't lose initcall return
values" (commit e662e1cfd4) had introduced
potential buffer overflow by wrong calculation of string accumulator
size.

Use strlcat() instead, fixing both bugs.

Many thanks Andreas Schwab and Geert Uytterhoeven for helping
to catch and fix the bug.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-15 18:20:06 -07:00
Linus Torvalds
e0df154f45 Split up 'do_initcalls()' into two simpler functions
One function to just loop over the entries, one function to actually do
the call and the associated debugging code.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-15 18:14:01 -07:00
Linus Torvalds
a442ac512f Clean up 'print_fn_descriptor_symbol()' types
Everybody wants to pass it a function pointer, and in fact, that is what
you _must_ pass it for it to make sense (since it knows that ia64 and
ppc64 use descriptors for function pointers and fetches the actual
address from there).

So don't make the argument be a 'unsigned long' and force everybody to
add a cast.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-15 17:50:37 -07:00
Kay Sievers
30f2f0eb4b block: do_mounts - accept root=<non-existant partition>
Some devices, like md, may create partitions only at first access,
so allow root= to be set to a valid non-existant partition of an
existing disk. This applies only to non-initramfs root mounting.

This fixes a regression from 2.6.24 which did allow this to happen and
broke some users machines :(

Acked-by: Neil Brown <neilb@suse.de>
Tested-by: Joao Luis Meloni Assirati <assirati@nonada.if.usp.br>
Cc: stable <stable@kernel.org>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-05-14 10:37:57 -07:00
Cyrill Gorcunov
e662e1cfd4 init: don't lose initcall return values
There is an ability to lose an initcall return value if it happened with irq
disabled or imbalanced preemption (and if we debug initcall).

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-13 08:02:25 -07:00
Rusty Russell
91e37a793b module: don't ignore vermagic string if module doesn't have modversions
Linus found a logic bug: we ignore the version number in a module's
vermagic string if we have CONFIG_MODVERSIONS set, but modversions
also lets through a module with no __versions section for modprobe
--force (with tainting, but still).

We should only ignore the start of the vermagic string if the module
actually *has* crcs to check.  Rather than (say) having an
entertaining hissy fit and creating a config option to work around the
buggy code.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-09 07:45:18 -07:00
Stas Sergeev
e5e1d3cb20 pcspkr: fix dependancies
fix pcspkr dependancies: make the pcspkr platform
drivers to depend on a platform device, and
not the other way around.

Signed-off-by: Stas Sergeev <stsp@aknet.ru>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
CC: Vojtech Pavlik <vojtech@suse.cz>
CC: Michael Opdenacker <michael-lists@free-electrons.com>
[fixed for 2.6.26-rc1 by tiwai]
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2008-05-07 12:42:03 +02:00
Parag Warudkar
aac6abca85 sched: default to n for GROUP_SCHED and FAIR_GROUP_SCHED
GROUP_SCHED is confirmed to cause unacceptable latencies, see:

   http://lkml.org/lkml/2008/5/2/370.

Mark it EXPERIMENTAL and default to no for now.

Signed-off-by: Parag Warudkar <parag.warudkar@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-05 23:56:18 +02:00
Peter Zijlstra
3e51f33fcc sched: add optional support for CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
this replaces the rq->clock stuff (and possibly cpu_clock()).

 - architectures that have an 'imperfect' hardware clock can set
   CONFIG_HAVE_UNSTABLE_SCHED_CLOCK

 - the 'jiffie' window might be superfulous when we update tick_gtod
   before the __update_sched_clock() call in sched_clock_tick()

 - cpu_clock() might be implemented as:

     sched_clock_cpu(smp_processor_id())

   if the accuracy proves good enough - how far can TSC drift in a
   single jiffie when considering the filtering and idle hooks?

[ mingo@elte.hu: various fixes and cleanups ]

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-05 23:56:18 +02:00
Ingo Molnar
a5574cf65b sched, x86: add HAVE_UNSTABLE_SCHED_CLOCK
add the HAVE_UNSTABLE_SCHED_CLOCK, for architectures to select.

the next change utilizes it.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-05 23:56:18 +02:00
Linus Torvalds
826e4506a0 Make forced module loading optional
The kernel module loader used to be much too happy to allow loading of
modules for the wrong kernel version by default.  For example, if you
had MODVERSIONS enabled, but tried to load a module with no version
info, it would happily load it and taint the kernel - whether it was
likely to actually work or not!

Generally, such forced module loading should be considered a really
really bad idea, so make it conditional on a new config option
(MODULE_FORCE_LOAD), and make it default to off.

If somebody really wants to force module loads, that's their problem,
but we should not encourage it.  Especially as it happened to me by
mistake (ie regular unversioned Fedora modules getting loaded) causing
lots of strange behavior.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-04 17:04:16 -07:00
Christoph Lameter
f6acb63508 slub: #ifdef simplification
If we make SLUB_DEBUG depend on SYSFS then we can simplify some
#ifdefs and avoid others.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
2008-05-02 00:27:13 +03:00
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
Pavel Emelyanov
5cd204550b Deprecate find_task_by_pid()
There are some places that are known to operate on tasks'
global pids only:

* the rest_init() call (called on boot)
* the kgdb's getthread
* the create_kthread() (since the kthread is run in init ns)

So use the find_task_by_pid_ns(..., &init_pid_ns) there
and schedule the find_task_by_pid for removal.

[sukadev@us.ibm.com: Fix warning in kernel/pid.c]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:48 -07:00
Oleg Nesterov
fae5fa44f1 signals: fix /sbin/init protection from unwanted signals
The global init has a lot of long standing problems with the unhandled fatal
signals.

	- The "is_global_init(current)" check in get_signal_to_deliver()
	  protects only the main thread. Sub-thread can dequee the fatal
	  signal and shutdown the whole thread group except the main thread.
	  If it dequeues SIGSTOP /sbin/init will be stopped, this is not
	  right too. Note that we can't use is_global_init(->group_leader),
	  this breaks exec and this can't solve other problems we have.

	- Even if afterwards ignored, the fatal signals sets SIGNAL_GROUP_EXIT
	  on delivery. This breaks exec, has other bad implications, and this
	  is just wrong.

Introduce the new SIGNAL_UNKILLABLE flag to fix these problems.  It also helps
to solve some other problems addressed by the subsequent patches.

Currently we use this flag for the global init only, but it could also be used
by kthreads and (perhaps) by the sub-namespace inits.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30 08:29:37 -07:00
Akinobu Mita
199f0ca514 idr: create idr_layer_cache at boot time
Avoid a possible kmem_cache_create() failure by creating idr_layer_cache
unconditionary at boot time rather than creating it on-demand when idr_init()
is called the first time.

This change also enables us to eliminate the check every time idr_init() is
called.

[akpm@linux-foundation.org: rename init_id_cache() to idr_init_cache()]
[akpm@linux-foundation.org: fix alpha build]
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>
2008-04-29 08:06:25 -07:00
Holger Schurig
88f458e4b9 sysctl: allow embedded targets to disable sysctl_check.c
Disable sysctl_check.c for embedded targets. This saves about about 11 kB
in .text and another 11 kB in .data on a PXA255 embedded platform.

Signed-off-by: Holger Schurig <hs4233@mail.mn-solutions.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:22 -07:00
Balbir Singh
cf475ad28a cgroups: add an owner to the mm_struct
Remove the mem_cgroup member from mm_struct and instead adds an owner.

This approach was suggested by Paul Menage.  The advantage of this approach
is that, once the mm->owner is known, using the subsystem id, the cgroup
can be determined.  It also allows several control groups that are
virtually grouped by mm_struct, to exist independent of the memory
controller i.e., without adding mem_cgroup's for each controller, to
mm_struct.

A new config option CONFIG_MM_OWNER is added and the memory resource
controller selects this config option.

This patch also adds cgroup callbacks to notify subsystems when mm->owner
changes.  The mm_cgroup_changed callback is called with the task_lock() of
the new task held and is called just prior to changing the mm->owner.

I am indebted to Paul Menage for the several reviews of this patchset and
helping me make it lighter and simpler.

This patch was tested on a powerpc box, it was compiled with both the
MM_OWNER config turned on and off.

After the thread group leader exits, it's moved to init_css_state by
cgroup_exit(), thus all future charges from runnings threads would be
redirected to the init_css_set's subsystem.

Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Pavel Emelianov <xemul@openvz.org>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Sudhir Kumar <skumar@linux.vnet.ibm.com>
Cc: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Cc: Hirokazu Takahashi <taka@valinux.co.jp>
Cc: David Rientjes <rientjes@google.com>,
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Reviewed-by: Paul Menage <menage@google.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:10 -07:00
Serge E. Hallyn
08ce5f16ee cgroups: implement device whitelist
Implement a cgroup to track and enforce open and mknod restrictions on device
files.  A device cgroup associates a device access whitelist with each cgroup.
 A whitelist entry has 4 fields.  'type' is a (all), c (char), or b (block).
'all' means it applies to all types and all major and minor numbers.  Major
and minor are either an integer or * for all.  Access is a composition of r
(read), w (write), and m (mknod).

The root device cgroup starts with rwm to 'all'.  A child devcg gets a copy of
the parent.  Admins can then remove devices from the whitelist or add new
entries.  A child cgroup can never receive a device access which is denied its
parent.  However when a device access is removed from a parent it will not
also be removed from the child(ren).

An entry is added using devices.allow, and removed using
devices.deny.  For instance

	echo 'c 1:3 mr' > /cgroups/1/devices.allow

allows cgroup 1 to read and mknod the device usually known as
/dev/null.  Doing

	echo a > /cgroups/1/devices.deny

will remove the default 'a *:* mrw' entry.

CAP_SYS_ADMIN is needed to change permissions or move another task to a new
cgroup.  A cgroup may not be granted more permissions than the cgroup's parent
has.  Any task can move itself between cgroups.  This won't be sufficient, but
we can decide the best way to adequately restrict movement later.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix may-be-used-uninitialized warning]
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Acked-by: James Morris <jmorris@namei.org>
Looks-good-to: Pavel Emelyanov <xemul@openvz.org>
Cc: Daniel Hokka Zakrisson <daniel@hozac.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:09 -07:00
Paul Menage
418d7d875c CGroup API files: make CGROUP_DEBUG default to off
The cgroup debug subsystem isn't generally useful for users.  It should
default to "n".

Signed-off-by: Paul Menage <menage@google.com>
Cc: "Li Zefan" <lizf@cn.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: "YAMAMOTO Takashi" <yamamoto@valinux.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:09 -07:00
Thomas Petazzoni
3265e66b18 directly use kmalloc() and kfree() in init/initramfs.c
Instead of using the malloc() and free() wrappers needed by the
lib/inflate.c code for allocations, simply use kmalloc() and kfree() in the
initramfs code.  This is needed for a further lib/inflate.c-related cleanup
patch that will remove the malloc() and free() functions.

Take that opportunity to remove the useless kmalloc() return value
cast.

Based on work done by Matt Mackall.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Matt Mackall <mpm@selenic.com>
Cc: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:06 -07:00
Bjorn Helgaas
626adeb667 Simplify initcall_debug output
print_fn_descriptor_symbol() prints the address if we don't have a symbol, so
no need to print both.

Also, combine printing return value with elapsed time.  Changes this:

  Calling initcall 0xc05b7a70: pci_mmcfg_late_insert_resources+0x0/0x50()
  initcall 0xc05b7a70: pci_mmcfg_late_insert_resources+0x0/0x50() returned 1.
  initcall 0xc05b7a70 ran for 0 msecs: pci_mmcfg_late_insert_resources+0x0/0x50()
  initcall at 0xc05b7a70: pci_mmcfg_late_insert_resources+0x0/0x50(): returned with error code 1

to this:

  calling  pci_mmcfg_late_insert_resources+0x0/0x50()
  initcall pci_mmcfg_late_insert_resources+0x0/0x50() returned 1 after 0 msecs
  initcall pci_mmcfg_late_insert_resources+0x0/0x50() returned with error code 1

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:02 -07:00
Adrian Bunk
f17a32e97e let LOG_BUF_SHIFT default to 17
16 kB is often no longer enough for a normal boot of an UP system.

And even less when people e.g. use suspend.

17 seems to be a more reasonable default for current kernels on current
hardware (it's just the default, anyone who is memory limited can still lower
it).

Signed-off-by: Adrian Bunk <bunk@kernel.org>
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>
2008-04-29 08:06:01 -07:00
Harvey Harrison
d613c3e2d8 init: fix integer as NULL pointer warnings
init/do_mounts_rd.c:215:13: warning: Using plain integer as NULL pointer
init/do_mounts_md.c:136:45: warning: Using plain integer as NULL pointer

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 17:29:18 -07:00
Linus Torvalds
e945e849e1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
  sparc: video drivers: add facility level
  sparc: tcx.c make tcx_init and tcx_exit static
  sparc: ffb.c make ffb_init and ffb_exit static
  sparc: cg14.c make cg14_init and cg15_exit static
  sparc: bw2.c fix bw2_exit
  sparc64: Fix accidental syscall restart on child return from clone/fork/vfork.
  sparc64: Clean up handling of pt_regs trap type encoding.
  sparc: Remove old style signal frame support.
  sparc64: Kill bogus RT_ALIGNEDSZ macro from signal.c
  sparc: sunzilog.c remove unused argument
  sparc: fix drivers/video/tcx.c warning
  sparc64: Kill unused local ISA bus layer.
  input: Rewrite sparcspkr device probing.
  sparc64: Do not ignore 'pmu' device ranges.
  sparc64: Kill ISA_FLOPPY_WORKS code.
  sparc64: Kill CONFIG_SPARC32_COMPAT
  sparc64: Cleanups and corrections for arch/sparc64/Kconfig
  sparc64: Fix wedged irq regression.
2008-04-28 09:45:57 -07:00
Ingo Molnar
96fffeb4b4 make CC_OPTIMIZE_FOR_SIZE non-experimental
this option has been the default on a wide range of distributions
for a long time - time to make it non-experimental.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 09:42:46 -07:00
David S. Miller
09337f501e sparc64: Kill CONFIG_SPARC32_COMPAT
It's completely superfluous, CONFIG_COMPAT is sufficient.

What this used to be is an umbrella for enabling code shared
by all 32-bit compat binary support types.  But with the
removal of SunOS and Solaris support, the only one left is
Linux 32-bit ELF.

Update defconfig.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-26 21:41:19 -07:00
Benjamin Herrenschmidt
839ad62e75 [POWERPC] Use __weak macro for smp_setup_processor_id
Use the __weak macro instead of the longer __attribute__ ((weak)) form
in one place in init/main.c.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
--

 init/main.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-24 20:57:33 +10:00
Benjamin Herrenschmidt
8c9843e57a [POWERPC] Add thread_info_cache_init() weak hook
Some architectures need to maintain a kmem cache for thread info
structures.  The next commit adds that to powerpc to fix an alignment
problem.

There is no good arch callback to use to initialize that cache
that I can find, so this adds a new one in the form of a weak
function whose default is empty.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-24 20:57:33 +10:00
Viktor Radnai
b9b158fe1c sched: better rt-group documentation
Viktor was nice enough to enhance the document based on my replies to
his questions on the subject.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-19 19:45:01 +02:00
Mike Travis
e0982e90cd init: move setup of nr_cpu_ids to as early as possible
Move the setting of nr_cpu_ids from sched_init() to start_kernel()
so that it's available as early as possible.

Note that an arch has the option of setting it even earlier if need be,
but it should not result in a different value than the setup_nr_cpu_ids()
function.

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-19 19:44:59 +02:00
Mike Travis
321a8e9dcb cpumask: add CPU_MASK_ALL_PTR macro
* Add a static cpumask_t variable "CPU_MASK_ALL_PTR" to use as
    a pointer reference to CPU_MASK_ALL.  This reduces where possible
    the instances where CPU_MASK_ALL allocates and fills a large
    array on the stack.  Used only if NR_CPUS > BITS_PER_LONG.

  * Change init/main.c to use new set_cpus_allowed_ptr().

Depends on:
	[sched-devel]: sched: add new set_cpus_allowed_ptr function

Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-19 19:44:59 +02:00
Christoph Lameter
0f389ec630 slub: No need for per node slab counters if !SLUB_DEBUG
The per node counters are used mainly for showing data through the sysfs API.
If that API is not compiled in then there is no point in keeping track of this
data. Disable counters for the number of slabs and the number of total slabs
if !SLUB_DEBUG. Incrementing the per node counters is also accessing a
potentially contended cacheline so this could actually be a performance
benefit to embedded systems.

SLABINFO support is also affected. It now must depends on SLUB_DEBUG (which
is on by default).

Patch also avoids a check for a NULL kmem_cache_node pointer in new_slab()
if the system is not compiled with NUMA support.

[penberg@cs.helsinki.fi: fix oops and move ->nr_slabs into CONFIG_SLUB_DEBUG]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
2008-04-14 18:53:02 +03:00