While an earlier patch already did a small step into that direction,
this patch moves initialization of all memory end variables to as
early as possible, so that dependent code doesn't need to check
whether these variables have already been set.

Also, remove a misleading (perhaps just outdated) comment, and make
static a variable only used in a single file.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Signed-off-by: NAndi Kleen <ak@suse.de>

CVS hasn't been used for a long time for them.
Signed-off-by: NAndi Kleen <ak@suse.de>

Makes code a little shorter.
Signed-off-by: NAndi Kleen <ak@suse.de>

No functional changes.

Cc: len.brown@intel.com
Signed-off-by: NAndi Kleen <ak@suse.de>

They are not used in this file so remove them. i386 didn't have them either.

Cc: len.brown@intel.com
Signed-off-by: NAndi Kleen <ak@suse.de>

It used to contain support code for NUMAQ, but that is long gone already
on 64bit.
Signed-off-by: NAndi Kleen <ak@suse.de>

Since we only support PCI and ISA legacy busses now there is no need to
have an full array with checking.
Signed-off-by: NAndi Kleen <ak@suse.de>

They did not really belong into io_apic.c. Move them into a new file
and clean it up a bit.

Also remove outdated ATI quirk that was obsolete,
Signed-off-by: NAndi Kleen <ak@suse.de>

The MPS table specification says that the operating system should
renumber the IO-APICs following the table as needed.  However in
ACPI this is not allowed or neeeded and all x86-64 systems are ACPI
compliant.

The code was already disabled on some systems because it caused
problems there. Remove it completely now.

CC: mdomsch@dell.com
Signed-off-by: NAndi Kleen <ak@suse.de>

The IO APIC code had lots of duplicated code to read/write 64bit
routing entries into the IO-APIC. Factor this out int common read/write
functions

In a few cases the IO APIC lock is taken more often now, but this
isn't a problem because it's all initialization/shutdown only
slow path code.
Signed-off-by: NAndi Kleen <ak@suse.de>

It apparently has never triggered in many years.
Signed-off-by: NAndi Kleen <ak@suse.de>

PIC mode is an outdated way to drive the APICs that was used on
some early MP boards. It is not supported in the ACPI model.

It is unlikely to be ever configured by any x86-64 system

Remove it thus.
Signed-off-by: NAndi Kleen <ak@suse.de>

No 64bit EISA or Microchannel systems ever. Remove the left over code
in the IO-APIC driver and the mptable parser
Signed-off-by: NAndi Kleen <ak@suse.de>

This was an old workaround for broken MP-BIOS. The user could
specify overwrites on the command line.

I've never seen it being used for anything on 64bit. So get
rid of it for now.
Signed-off-by: NAndi Kleen <ak@suse.de>

And remove some old obsolete ones.
Signed-off-by: NAndi Kleen <ak@suse.de>

The new systems already use focus disabled and the comment was
completely outdated.
Signed-off-by: NAndi Kleen <ak@suse.de>

Nobody has been setting the mismatch counter and the ifdef was never
set so remove it.
Signed-off-by: NAndi Kleen <ak@suse.de>

IO-APIC or local APIC can only be disabled at runtime anyways and
Kconfig has forced these options on for a long time now.

The Kconfigs are kept only now for the benefit of the shared acpi
boot.c code.
Signed-off-by: NAndi Kleen <ak@suse.de>

Signed-off-by: NAndi Kleen <ak@suse.de>

Previously it didn't align. Use the same one as the C compiler
in blended mode, which is good for K8 and Core2 and doesn't hurt
on P4.
Signed-off-by: NAndi Kleen <ak@suse.de>

Use knowledge about EFLAGS layout (bits 22:63 are always 0) to distingush
EFLAGS word and kernel address in the spin lock stack frame.
Signed-off-by: NAndi Kleen <ak@suse.de>

Based on patch from Frank van Maarseveen <frankvm@frankvm.com>, but
extended.
Signed-off-by: NAndi Kleen <ak@suse.de>

A few trivial spelling and grammar mistakes picked up in
"arch/x86_64/aperture.c", "arch/x86_64/crash.c" and
"arch/x86_64/apic.c". I think all are correct fixes but am ever aware
of my fallibility :o) This is my first patch submission so all
feedback is appreciated, esp. WRT CCing to Linus, Andi and
trivial@kernel.org, is this correct? And which is the most appropriate
kernel version to diff against? If any.

Should apply cleanly to 2.6.18-rc1
Signed-off-by: NAdam Henley <adamazing@gmail.com>
Signed-off-by: NAndi Kleen <ak@suse.de>

-  adam

Hello,

Following my discussion with Andi. Here is a patch that introduces
two new TIF flags to simplify the context switch code in __switch_to().
The idea is to minimize the number of cache lines accessed in the common
case, i.e., when neither the debug registers nor the I/O bitmap are used.

This patch covers the x86-64 modifications. A patch for i386 follows.

Changelog:
	- add TIF_DEBUG to track when debug registers are active
	- add TIF_IO_BITMAP to track when I/O bitmap is used
	- modify __switch_to() to use the new TIF flags

<signed-off-by>: eranian@hpl.hp.com
Signed-off-by: NAndi Kleen <ak@suse.de>

No need to include it from entry.S
Drop all the #ifdef __ASSEMBLY__
Signed-off-by: NAndi Kleen <ak@suse.de>

This patch adds a vgetcpu vsyscall, which depending on the CPU RDTSCP
capability uses either the RDTSCP or CPUID to obtain a CPU and node
numbers and pass them to the program.

AK: Lots of changes over Vojtech's original code:
Better prototype for vgetcpu()
It's better to pass the cpu / node numbers as separate arguments
to avoid mistakes when going from SMP to NUMA.
Also add a fast time stamp based cache using a user supplied
argument to speed things more up.
Use fast method from Chuck Ebbert to retrieve node/cpu from
GDT limit instead of CPUID
Made sure RDTSCP init is always executed after node is known.
Drop printk
Signed-off-by: NVojtech Pavlik <vojtech@suse.cz>
Signed-off-by: NAndi Kleen <ak@suse.de>

This patch adds initalization of the RDTSCP auxilliary values to CPU numbers
to time.c. If RDTSCP is available, the MSRs are written with the respective
values. It can be later used to initalize per-cpu timekeeping variables.

AK: Some cleanups. Move externs into headers and fix CPU hotplug.
Signed-off-by: NVojtech Pavlik <vojtech@suse.cz>
Signed-off-by: NAndi Kleen <ak@suse.de>

AK: This redoes the changes I temporarily reverted.

Intel now has support for Architectural Performance Monitoring Counters
( Refer to IA-32 Intel Architecture Software Developer's Manual
http://www.intel.com/design/pentium4/manuals/253669.htm ). This
feature is present starting from Intel Core Duo and Intel Core Solo processors.

What this means is, the performance monitoring counters and some performance
monitoring events are now defined in an architectural way (using cpuid).
And there will be no need to check for family/model etc for these architectural
events.

Below is the patch to use this performance counters in nmi watchdog driver.
Patch handles both i386 and x86-64 kernels.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NAndi Kleen <ak@suse.de>

After a crash we should wait for NMI IPI event and not for external NMI or
NMI watchdog tick.
Signed-off-by: NVivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>

When a unknown NMI happened the panic would claim a NMI watchdog timeout.
Also it would check the variable set by nmi_watchdog=panic and panic then.

Fix up the panic message to be generic
Unconditionally panic on unknown NMI when panic on unknown nmi is enabled.

Noticed by Jan Beulich

Cc: jbeulich@novell.com
Signed-off-by: NAndi Kleen <ak@suse.de>

Making NMI suspend/resume work with SMP. We use CPU hotplug to offline
APs in SMP suspend/resume. Only BSP executes sysdev's .suspend/.resume
method. APs should follow CPU hotplug code path.

And:

+From: Don Zickus <dzickus@redhat.com>

Makes the start/stop paths of nmi watchdog more robust to handle the
suspend/resume cases more gracefully.

AK: I merged the two patches together
Signed-off-by: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>

Clean up some of the output messages on the nmi error paths to make more
sense when they are displayed.  This is mainly a cosmetic fix and
shouldn't impact any normal code path.
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Signed-off-by: NAndi Kleen <ak@suse.de>

To quote Alan Cox:

The default Linux behaviour on an NMI of either memory or unknown is to
continue operation. For many environments such as scientific computing
it is preferable that the box is taken out and the error dealt with than
an uncorrected parity/ECC error get propogated.

A small number of systems do generate NMI's for bizarre random reasons
such as power management so the default is unchanged. In other respects
the new proc/sys entry works like the existing panic controls already in
that directory.

This is separate to the edac support - EDAC allows supported chipsets to
handle ECC errors well, this change allows unsupported cases to at least
panic rather than cause problems further down the line.
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Signed-off-by: NAndi Kleen <ak@suse.de>

Adds a new /proc/sys/kernel/nmi_watchdog call that will enable/disable the
nmi watchdog.

By entering a non-zero value here, a user can enable the nmi watchdog to
monitor the online cpus in the system.  By entering a zero value here, a
user can disable the nmi watchdog and free up a performance counter which
could then be utilized by the oprofile subsystem, otherwise oprofile may be
short a counter when in use.
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Signed-off-by: NAndi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>

Adds a new /proc/sys/kernel/nmi call that will enable/disable the nmi
watchdog.
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Signed-off-by: NAndi Kleen <ak@suse.de>

Removes the un/set_nmi_callback and reserve/release_lapic_nmi functions as
they are no longer needed.  The various subsystems are modified to register
with the die_notifier instead.

Also includes compile fixes by Andrew Morton.
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Signed-off-by: NAndi Kleen <ak@suse.de>

We need TIF_RESTORE_SIGMASK in order to support ppoll() and pselect()
system calls. This patch originally came from Andi, and was based
heavily on David Howells' implementation of same on i386. I fixed a typo
which was causing do_signal() to use the wrong signal mask.
Signed-off-by: NDavid Woodhouse <dwmw2@infradead.org>
Signed-off-by: NAndi Kleen <ak@suse.de>

This patch cleans up the NMI interrupt path.  Instead of being gated by if
the 'nmi callback' is set, the interrupt handler now calls everyone who is
registered on the die_chain and additionally checks the nmi watchdog,
reseting it if enabled.  This allows more subsystems to hook into the NMI if
they need to (without being block by set_nmi_callback).
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Signed-off-by: NAndi Kleen <ak@suse.de>

This patch includes the changes to make the nmi watchdog on x86_64 SMP
aware.  A bunch of code was moved around to make it simpler to read.  In
addition, it is now possible to determine if a particular NMI was the result
of the watchdog or not.  This feature allows the kernel to filter out
unknown NMIs easier.
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Signed-off-by: NAndi Kleen <ak@suse.de>

Adds basic infrastructure to allow subsystems to reserve performance
counters on the x86 chips.  Only UP kernels are supported in this patch to
make reviewing easier.  The SMP portion makes a lot more changes.

Think of this as a locking mechanism where each bit represents a different
counter.  In addition, each subsystem should also reserve an appropriate
event selection register that will correspond to the performance counter it
will be using (this is mainly neccessary for the Pentium 4 chips as they
break the 1:1 relationship to performance counters).

This will help prevent subsystems like oprofile from interfering with the
nmi watchdog.
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Signed-off-by: NAndi Kleen <ak@suse.de>