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: NIngo Molnar <mingo@elte.hu>

Impact: adds new Kconfig entry
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

These two IOMMUs can implement the current version of this API. So
select the API if one or both of these IOMMU drivers is selected.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

Impact: improve help text
Signed-off-by: NIngo Molnar <mingo@elte.hu>

New feature - lets disable it by default first - can flip it around
later.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: reduce kconfig variable scope and clean up

Bartlomiej pointed out that the config dependencies and comments are not right.

update it depend to NUMA, and fix some comments
Reported-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NMike Travis <travis@sgi.com>

Impact: activates new off-stack cpumask code on MAXSMP (non-default) x86 configs

Set MAXSMP to enable CONFIG_CPUMASK_OFFSTACK which moves cpumask's off
the stack (and in structs) when using cpumask_var_t.
Signed-off-by: NMike Travis <travis@sgi.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Acked-by: NIngo Molnar <mingo@elte.hy>

Impact: build fix

make intr_remapping.c to include smp.h, so could use boot_cpu_id there

also remove old change that disabling sparseirq with !SMP
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: improve NUMA handling by migrating irq_desc on smp_affinity changes

if CONFIG_NUMA_MIGRATE_IRQ_DESC is set:

-  make irq_desc to go with affinity aka irq_desc moving etc
-  call move_irq_desc in irq_complete_move()
-  legacy irq_desc is not moved, because they are allocated via static array

for logical apic mode, need to add move_desc_in_progress_in_same_domain,
otherwise it will not be moved ==> also could need two phases to get
irq_desc moved.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: reduce bug table size

This allows reducing the bug table size by half. Perhaps there are
other 64-bit architectures that could also make use of this.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Ingo Molnar wrote:

>>>  drivers/pci/intr_remapping.c: In function 'irq_2_iommu_alloc':
>>>  drivers/pci/intr_remapping.c:72: error: 'boot_cpu_id' undeclared (first use in this function)
>>>  drivers/pci/intr_remapping.c:72: error: (Each undeclared identifier is reported only once
>>>  drivers/pci/intr_remapping.c:72: error: for each function it appears in.)

sparseirq should only be used with SMP for now.

Impact: new feature

Problem on distro kernels: irq_desc[NR_IRQS] takes megabytes of RAM with
NR_CPUS set to large values. The goal is to be able to scale up to much
larger NR_IRQS value without impacting the (important) common case.

To solve this, we generalize irq_desc[NR_IRQS] to an (optional) array of
irq_desc pointers.

When CONFIG_SPARSE_IRQ=y is used, we use kzalloc_node to get irq_desc,
this also makes the IRQ descriptors NUMA-local (to the site that calls
request_irq()).

This gets rid of the irq_cfg[] static array on x86 as well: irq_cfg now
uses desc->chip_data for x86 to store irq_cfg.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Remove CONFIG_APM_REAL_MODE_POWER_OFF like CONFIG_APM_POWER_OFF which
has been done for linux-2.2.14pre8 (http://lkml.org/lkml/1999/11/23/3).

Re-introducing CONFIG_APM_POWER_OFF got nack-ed. Stephen didn't bother
to remove CONFIG_APM_REAL_MODE_POWER_OFF, let's get rid of it now.
	Reference: http://lkml.org/lkml/2008/5/7/97Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: extend and enable the function graph tracer to 64-bit x86

This patch implements the support for function graph tracer under x86-64.
Both static and dynamic tracing are supported.

This causes some small CPP conditional asm on arch/x86/kernel/ftrace.c I
wanted to use probe_kernel_read/write to make the return address
saving/patching code more generic but it causes tracing recursion.

That would be perhaps useful to implement a notrace version of these
function for other archs ports.

Note that arch/x86/process_64.c is not traced, as in X86-32. I first
thought __switch_to() was responsible of crashes during tracing because I
believed current task were changed inside but that's actually not the
case (actually yes, but not the "current" pointer).

So I will have to investigate to find the functions that harm here, to
enable tracing of the other functions inside (but there is no issue at
this time, while process_64.c stays out of -pg flags).

A little possible race condition is fixed inside this patch too. When the
tracer allocate a return stack dynamically, the current depth is not
initialized before but after. An interrupt could occur at this time and,
after seeing that the return stack is allocated, the tracer could try to
trace it with a random uninitialized depth. It's a prevention, even if I
hadn't problems with it.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tim Bird <tim.bird@am.sony.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: add new API for drivers

Add implementation of readq/writeq to x86_32, and add config value to
the x86 architecture to determine existence of readq/writeq.
Signed-off-by: NHitoshi Mitake <h.mitake@gmail.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

This patch changes the name of the "return function tracer" into
function-graph-tracer which is a more suitable name for a tracing
which makes one able to retrieve the ordered call stack during
the code flow.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: update documentation / help text

Original link is dead.
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

User stack tracing is just implemented for x86, but it is not x86 specific.

Introduce a generic config flag, that is currently enabled only for x86.
When other arches implement it, they will have to
SELECT USER_STACKTRACE_SUPPORT.
Signed-off-by: NTörök Edwin <edwintorok@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: clean up

We can autodetect those system that need cluster apic, and update genapic
accordingly.

We can also remove wakeup.h for e7000, because it's default one is now
the same as overall default mach_wakecpu.h
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: fixes korg bugzilla 11980

A kernel for a 64bit x86 system should always contain the swiotlb code
in case it is booted on a machine without any hardware IOMMU supported
by the kernel and more than 4GB of RAM. This patch changes Kconfig to
always compile swiotlb into the kernel for x86_64.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
Cc: stable@kernel.org
Signed-off-by: NIngo Molnar <mingo@elte.hu>

My previous patch to make CONFIG_NUMA on x86_32 depend on BROKEN
turned out to be unnecessary, after all, since the source of the
hibernation vs CONFIG_NUMA problem turned out to be the fact that
we didn't take the NUMA KVA remapping into account in the
hibernation code.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: documentation update

Chris Snook pointed out that it's Core i7, not Core 7i.
Reported-by: NChris Snook <csnook@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: build/boot fix for x86/Voyager

This change:

| commit 3d442233
| Author: Jens Axboe <jens.axboe@oracle.com>
| Date:   Thu Jun 26 11:21:34 2008 +0200
|
|     Add generic helpers for arch IPI function calls

didn't wire up the voyager smp call function correctly, so do that
here.  Also make CONFIG_USE_GENERIC_SMP_HELPERS a def_bool y again,
since we now use the generic helpers for every x86 architecture.
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <Jens.Axboe@oracle.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

move FUNCTION_RET_TRACER to the X86 select section, where we have all the
other options.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: add infrastructure for function-return tracing

Add low level support for ftrace return tracing.

This plug-in stores return addresses on the thread_info structure of
the current task.

The index of the current return address is initialized when the task
is the first one (init) and when a process forks (the child). It is
not needed when a task does a sys_execve because after this syscall,
it still needs to return on the kernel functions it called.

Note that the code of return_to_handler has been suggested by Steven
Rostedt as almost all of the ideas of improvements in this V3.

For purpose of security, arch/x86/kernel/process_32.c is not traced
because __switch_to() changes the current task during its execution.
That could cause inconsistency in the stored return address of this
function even if I didn't have any crash after testing with tracing on
this function enabled.
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup, change .config option name

We had this ugly config name for a long time for hysteric raisons.
Rename it to a saner name.

We still cannot get rid of it completely, until /proc/<pid>/stack
usage replaces WCHAN usage for good.

We'll be able to do that in the v2.6.29/v2.6.30 timeframe.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

While investigating the failure of hibernation on 32-bit x86 with
CONFIG_NUMA set, as described in this message
http://marc.info/?l=linux-kernel&m=122634118116226&w=4
I asked some people for help and I was told that it wasn't really
worth the effort, because CONFIG_NUMA was generally broken on 32-bit
x86 systems and it shouldn't be used in such configs.  For this
reason, make CONFIG_NUMA depend on BROKEN instead of EXPERIMENTAL on
x86-32.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Pavel Machek <pavel@suse.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Enable the wchan config menu item for now on x86-64 arch?  This will
at least allow people to enable/disable frame pointers on scheduler
functions.
Signed-off-by: NKen Chen <kenchen@google.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: clarify/update CONFIG_NUMA text

CONFIG_NUMA description talk about a bit old thing.
So, following changes are better.

 o CONFIG_NUMA is no longer EXPERIMENTAL

 o Opteron is not the only processor of NUMA topology on x86_64 no longer,
   but also Intel Core7i has it.
Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: clarify menuconfig text

Mention ACPI in the top-level menu to give a clue as to where
it lives. This matches what ia64 does.
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: quick start and stop of function tracer

This patch adds a way to disable the function tracer quickly without
the need to run kstop_machine. It adds a new variable called
function_trace_stop which will stop the calls to functions from mcount
when set.  This is just an on/off switch and does not handle recursion
like preempt_disable().

It's main purpose is to help other tracers/debuggers start and stop tracing
fuctions without the need to call kstop_machine.

The config option HAVE_FUNCTION_TRACE_MCOUNT_TEST is added for archs
that implement the testing of the function_trace_stop in the mcount
arch dependent code. Otherwise, the test is done in the C code.

x86 is the only arch at the moment that supports this.
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

clean up ifdefs: change #ifdef CONFIG_X86_32/64 to
CONFIG_HAVE_ATOMIC_IOMAP.

flip around the #ifdef sections to clean up the structure.
Signed-off-by: NKeith Packard <keithp@keithp.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: enable CONFIG_MEMORY_HOTREMOVE feature on x86. (default-off)

Memory hotremove functionality can currently be configured into
the ia64, powerpc, and s390 kernels.

This patch makes it possible to configure the memory hotremove
functionality into the x86 kernel as well.
Signed-off-by: NBadari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: NGary Hade <garyhade@us.ibm.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: build fix on x86/Voyager

Given commits like this:

| Author: Suresh Siddha <suresh.b.siddha@intel.com>
| Date:   Tue Jul 29 10:29:19 2008 -0700
|
|     x86, xsave: enable xsave/xrstor on cpus with xsave support

Which deliberately expose boot cpu dependence to pieces of the system,
I think it's time to explicitly have a variable for it to prevent this
continual misassumption that the boot CPU is zero.
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

DIRECT_GBPAGES was under DEBUG_KERNEL && EXPERIMENTAL and disabled by default.
Turn it on by default and put it under EMBEDDED.
Signed-off-by: NNick Piggin <npiggin@suse.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The Intel 7300 Memory Controller supports dynamic throttling of memory which can
be used to save power when system is idle. This driver does the memory
throttling when all CPUs are idle on such a system.

Refer to "Intel 7300 Memory Controller Hub (MCH)" datasheet
for the config space description.
Signed-off-by: NAndy Henroid <andrew.d.henroid@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>

Due to confusion between the ftrace infrastructure and the gcc profiling
tracer "ftrace", this patch renames the config options from FTRACE to
FUNCTION_TRACER.  The other two names that are offspring from FTRACE
DYNAMIC_FTRACE and FTRACE_MCOUNT_RECORD will stay the same.

This patch was generated mostly by script, and partially by hand.
Signed-off-by: NSteven Rostedt <srostedt@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This patch implements a new freezer subsystem in the control groups
framework.  It provides a way to stop and resume execution of all tasks in
a cgroup by writing in the cgroup filesystem.

The freezer subsystem in the container filesystem defines a file named
freezer.state.  Writing "FROZEN" to the state file will freeze all tasks
in the cgroup.  Subsequently writing "RUNNING" will unfreeze the tasks in
the cgroup.  Reading will return the current state.

* Examples of usage :

   # mkdir /containers/freezer
   # mount -t cgroup -ofreezer freezer  /containers
   # mkdir /containers/0
   # echo $some_pid > /containers/0/tasks

to get status of the freezer subsystem :

   # cat /containers/0/freezer.state
   RUNNING

to freeze all tasks in the container :

   # echo FROZEN > /containers/0/freezer.state
   # cat /containers/0/freezer.state
   FREEZING
   # cat /containers/0/freezer.state
   FROZEN

to unfreeze all tasks in the container :

   # echo RUNNING > /containers/0/freezer.state
   # cat /containers/0/freezer.state
   RUNNING

This is the basic mechanism which should do the right thing for user space
task in a simple scenario.

It's important to note that freezing can be incomplete.  In that case we
return EBUSY.  This means that some tasks in the cgroup are busy doing
something that prevents us from completely freezing the cgroup at this
time.  After EBUSY, the cgroup will remain partially frozen -- reflected
by freezer.state reporting "FREEZING" when read.  The state will remain
"FREEZING" until one of these things happens:

	1) Userspace cancels the freezing operation by writing "RUNNING" to
		the freezer.state file
	2) Userspace retries the freezing operation by writing "FROZEN" to
		the freezer.state file (writing "FREEZING" is not legal
		and returns EIO)
	3) The tasks that blocked the cgroup from entering the "FROZEN"
		state disappear from the cgroup's set of tasks.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: export thaw_process]
Signed-off-by: NCedric Le Goater <clg@fr.ibm.com>
Signed-off-by: NMatt Helsley <matthltc@us.ibm.com>
Acked-by: NSerge E. Hallyn <serue@us.ibm.com>
Tested-by: NMatt Helsley <matthltc@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>