found a system where x2apic reports an MSI-X irq initialization
failure:

[  302.859446] igbvf 0000:81:10.4: enabling device (0000 -> 0002)
[  302.874369] igbvf 0000:81:10.4: using 64bit DMA mask
[  302.879023] igbvf 0000:81:10.4: using 64bit consistent DMA mask
[  302.894386] igbvf 0000:81:10.4: enabling bus mastering
[  302.898171] igbvf 0000:81:10.4: setting latency timer to 64
[  302.914050] reserve_memtype added 0xefb08000-0xefb0c000, track uncached-minus, req uncached-minus, ret uncached-minus
[  302.933839] reserve_memtype added 0xefb28000-0xefb29000, track uncached-minus, req uncached-minus, ret uncached-minus
[  302.940367]   alloc irq_desc for 265 on node 4
[  302.956874]   alloc kstat_irqs on node 4
[  302.959452] alloc irq_2_iommu on node 0
[  302.974328] igbvf 0000:81:10.4: irq 265 for MSI/MSI-X
[  302.977778]   alloc irq_desc for 266 on node 4
[  302.980347]   alloc kstat_irqs on node 4
[  302.995312] free_memtype request 0xefb28000-0xefb29000
[  302.998816] igbvf 0000:81:10.4: Failed to initialize MSI-X interrupts.

... it turns out that when trying to enable MSI-X,
__assign_irq_vector(new, cfg_new, apic->target_cpus()) can not
get vector because for x2apic target-cpus returns cpumask_of(0)

Update that to online_mask like xapic.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Acked-by: NSuresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <4A785AFF.3050902@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

In uv_setup_irq(), the call to create_irq() initially assigns
IRQ vectors to cpu 0. The subsequent call to
assign_irq_vector() in arch_enable_uv_irq() migrates the IRQ to
another cpu and frees the cpu 0 vector - at least it will be
freed as soon as the "IRQ move" completes.

arch_enable_uv_irq() needs to send a cleanup IPI to complete
the IRQ move. Otherwise, assignment of GRU interrupts on large
systems (>200 cpus) will exhaust the cpu 0 interrupt vectors
and initialization of the GRU driver will fail.
Signed-off-by: NJack Steiner <steiner@sgi.com>
LKML-Reference: <20090720142840.GA8885@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

One system has socket 1 come up as BSP.

kexeced kernel reports BSP as:

[    1.524550] Initializing cgroup subsys cpuacct
[    1.536064] initial_apicid:20
[    1.537135] ht_mask_width:1
[    1.538128] core_select_mask:f
[    1.539126] core_plus_mask_width:5
[    1.558479] CPU: Physical Processor ID: 0
[    1.559501] CPU: Processor Core ID: 0
[    1.560539] CPU: L1 I cache: 32K, L1 D cache: 32K
[    1.579098] CPU: L2 cache: 256K
[    1.580085] CPU: L3 cache: 24576K
[    1.581108] CPU 0/0x20 -> Node 0
[    1.596193] CPU 0 microcode level: 0xffff0008

It doesn't have correct physical processor id and will get an
error:

[   38.840859] CPU0 attaching sched-domain:
[   38.848287]  domain 0: span 0,8,72 level SIBLING
[   38.851151]   groups: 0 8 72
[   38.858137]   domain 1: span 0,8-15,72-79 level MC
[   38.868944]    groups: 0,8,72 9,73 10,74 11,75 12,76 13,77 14,78 15,79
[   38.881383] ERROR: parent span is not a superset of domain->span
[   38.890724]    domain 2: span 0-7,64-71 level CPU
[   38.899237] ERROR: domain->groups does not contain CPU0
[   38.909229]     groups: 8-15,72-79
[   38.912547] ERROR: groups don't span domain->span
[   38.919665]     domain 3: span 0-127 level NODE
[   38.930739]      groups: 0-7,64-71 8-15,72-79 16-23,80-87 24-31,88-95 32-39,96-103 40-47,104-111 48-55,112-119 56-63,120-127

it turns out: we can not use current_cpu_data in phys_pgd_id
for x2apic.

identify_boot_cpu() is called by check_bugs() before
smp_prepare_cpus() and till smp_prepare_cpus() current_cpu_data
for bsp is assigned with boot_cpu_data.

Just make phys_pkg_id for x2apic is aligned to xapic.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Acked-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A6ADD0D.10002@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Change SGI UV default apicid mode to "physical". This is
required to match settings in the UV hub chip.
Signed-off-by: NJack Steiner <steiner@sgi.com>
LKML-Reference: <20090727143856.GA8905@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The UV BIOS has added additional MMR ranges that are mapped via
EFI virtual mode mappings. These ranges should be deleted from
ranges mapped by uv_system_init().
Signed-off-by: NJack Steiner <steiner@sgi.com>
Cc: linux-mm@kvack.org
LKML-Reference: <20090727143656.GA7698@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

UV blades may not have any blade-local memory. Add a field
(nid) to the UV blade structure to indicates whether the node
has local memory. This is needed by the GRU driver (pushed
separately).
Signed-off-by: NJack Steiner <steiner@sgi.com>
Cc: linux-mm@kvack.org
LKML-Reference: <20090727143507.GA7006@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The variable apic_numaq placed in noninit section references the
function wakeup_secondary_cpu_via_nmi(), which is in __cpuinit
section. Thus causes a section mismatch warning. To avoid such
mismatch we mark apic_numaq as __refdata.

We were warned by the following warning:

  WARNING: arch/x86/kernel/built-in.o(.data+0x932c): Section mismatch in
  reference from the variable apic_numaq to the function
  .cpuinit.text:wakeup_secondary_cpu_via_nmi()
Signed-off-by: NRakib Mullick <rakib.mullick@gmail.com>
LKML-Reference: <b9df5fa10907120407p6b4f67dtf4d563155488188a@mail.gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The variable apic_es7000_cluster references the function __cpuinit
wakeup_secondary_cpu_via_mip() from a noninit section. So we've been
warned by the following warning. To avoid possible collision between
init/noninit, its best to mark the variable as __refdata.

We were warned by the following warning:

  LD      arch/x86/kernel/apic/built-in.o
  WARNING: arch/x86/kernel/apic/built-in.o(.data+0x198c): Section
  mismatch in reference from the variable apic_es7000_cluster to the
  function .cpuinit.text:wakeup_secondary_cpu_via_mip()
Signed-off-by: NRakib Mullick <rakib.mullick@gmail.com>
LKML-Reference: <b9df5fa10907120404k6279a10ch5e9682432272706f@mail.gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Stephen reported that his DL585 G2 needed noapic after 2.6.22 (?)

Dann bisected it down to:
  commit 30a18d6c
  Date:   Tue Feb 19 03:21:20 2008 -0800

      x86: multi pci root bus with different io resource range, on
      64-bit

It turns out that:
  1. that AMD-based systems have two HT chains.
  2. BIOS doesn't allocate resources for BAR 6 of devices under 8132 etc
  3. that multi-peer-root patch will try to split root resources to peer
     root resources according to PCI conf of NB
  4. PCI core assigns unassigned resources, but they overlap with BARs
     that are used by ioapic addr of io4 and 8132.

The reason: at that point ioapic address are not inserted yet.  Solution
is to insert ioapic resources into the tree a bit earlier.
Reported-by: NStephen Frost <sfrost@snowman.net>
Reported-and-Tested-by: Ndann frazier <dannf@hp.com>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: stable@kernel.org
Signed-off-by: NJesse Barnes <jbarnes@jbarnes-g45.(none)>

Commit 5fd29d6c ("printk: clean up
handling of log-levels and newlines") changed printk semantics.  printk
lines with multiple KERN_<level> prefixes are no longer emitted as
before the patch.

<level> is now included in the output on each additional use.

Remove all uses of multiple KERN_<level>s in formats.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

setup_nox2apic() is writing 1 to disable_x2apic but no one is reading it.
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
LKML-Reference: <1246554239.2242.27.camel@jaswinder.satnam>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Instead of this:

[   75.690022] <7>printing local APIC contents on CPU#0/0:
[   75.704406] ... APIC ID:      00000000 (0)
[   75.707905] ... APIC VERSION: 00060015
[   75.722551] ... APIC TASKPRI: 00000000 (00)
[   75.725473] ... APIC PROCPRI: 00000000
[   75.728592] ... APIC LDR: 00000001
[   75.742137] ... APIC SPIV: 000001ff
[   75.744101] ... APIC ISR field:
[   75.746648] 0123456789abcdef0123456789abcdef
[   75.746649] <7>00000000000000000000000000000000

Improve the code to be saner and simpler and just print out
the bitfield in a single line using hexa values - not as a
(rather pointless) binary bitfield.

Partially reused Linus's initial fix for this.
Reported-and-Tested-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A4C43BC.90506@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

To support domain-isolation usages, the platform hardware must be
capable of uniquely identifying the requestor (source-id) for each
interrupt message. Without source-id checking for interrupt remapping
, a rouge guest/VM with assigned devices can launch interrupt attacks
to bring down anothe guest/VM or the VMM itself.

This patch adds source-id checking for interrupt remapping, and then
really isolates interrupts for guests/VMs with assigned devices.

Because PCI subsystem is not initialized yet when set up IOAPIC
entries, use read_pci_config_byte to access PCI config space directly.
Signed-off-by: NWeidong Han <weidong.han@intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Vegard Nossum reported:

[  503.576724] ACPI: Preparing to enter system sleep state S5
[  503.710857] Disabling non-boot CPUs ...
[  503.716853] Power down.
[  503.717770] ------------[ cut here ]------------
[  503.717770] WARNING: at arch/x86/kernel/apic/apic.c:249 native_apic_write_du)
[  503.717770] Hardware name: OptiPlex GX100
[  503.717770] Modules linked in:
[  503.717770] Pid: 2136, comm: halt Not tainted 2.6.30 #443
[  503.717770] Call Trace:
[  503.717770]  [<c154d327>] ? printk+0x18/0x1a
[  503.717770]  [<c1017358>] ? native_apic_write_dummy+0x38/0x50
[  503.717770]  [<c10360fc>] warn_slowpath_common+0x6c/0xc0
[  503.717770]  [<c1017358>] ? native_apic_write_dummy+0x38/0x50
[  503.717770]  [<c1036165>] warn_slowpath_null+0x15/0x20
[  503.717770]  [<c1017358>] native_apic_write_dummy+0x38/0x50
[  503.717770]  [<c1017173>] disconnect_bsp_APIC+0x63/0x100
[  503.717770]  [<c1019e48>] disable_IO_APIC+0xb8/0xc0
[  503.717770]  [<c1214231>] ? acpi_power_off+0x0/0x29
[  503.717770]  [<c1015e55>] native_machine_shutdown+0x65/0x80
[  503.717770]  [<c1015c36>] native_machine_power_off+0x26/0x30
[  503.717770]  [<c1015c49>] machine_power_off+0x9/0x10
[  503.717770]  [<c1046596>] kernel_power_off+0x36/0x40
[  503.717770]  [<c104680d>] sys_reboot+0xfd/0x1f0
[  503.717770]  [<c109daa0>] ? perf_swcounter_event+0xb0/0x130
[  503.717770]  [<c109db7d>] ? perf_counter_task_sched_out+0x5d/0x120
[  503.717770]  [<c102dfc6>] ? finish_task_switch+0x56/0xd0
[  503.717770]  [<c154da1e>] ? schedule+0x49e/0xb40
[  503.717770]  [<c10444b0>] ? sys_kill+0x70/0x160
[  503.717770]  [<c119d9db>] ? selinux_file_ioctl+0x3b/0x50
[  503.717770]  [<c10dd443>] ? sys_ioctl+0x63/0x70
[  503.717770]  [<c1003024>] sysenter_do_call+0x12/0x22
[  503.717770] ---[ end trace 8157b5d0ed378f15 ]---

|
| That's including this commit:
|
| commit 103428e5
|Author: Cyrill Gorcunov <gorcunov@openvz.org>
|Date:   Sun Jun 7 16:48:40 2009 +0400
|
|    x86, apic: Fix dummy apic read operation together with broken MP handling
|

If we have apic disabled we don't even switch to APIC mode and do not
calling for connect_bsp_APIC. Though on SMP compiled kernel the
native_machine_shutdown does try to write the apic register anyway.

Fix it with explicit check if we really should touch apic registers.
Reported-by: NVegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: NCyrill Gorcunov <gorcunov@openvz.org>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <20090617181322.GG10822@lenovo>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NHuang Weiyi <weiyi.huang@gmail.com>
LKML-Reference: <1244895686-2348-1-git-send-email-weiyi.huang@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This compiler warning:

  arch/x86/kernel/apic/io_apic.c: In function ‘ioapic_write_entry’:
  arch/x86/kernel/apic/io_apic.c:466: warning: ‘eu’ is used uninitialized in this function
  arch/x86/kernel/apic/io_apic.c:465: note: ‘eu’ was declared here

Is bogus as 'eu' is always initialized. But annotate it away by
initializing the variable, to make it easier for people to notice
real warnings. A compiler that sees through this logic will
optimize away the initialization.
Signed-off-by: NFigo.zhang <figo1802@gmail.com>
LKML-Reference: <1245248720.3312.27.camel@myhost>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

So we make sure MAXSMP gets a cleared cpumask
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Don't hardcode to node zero for early boot IRQ setup memory allocations.

[ penberg@cs.helsinki.fi: minor cleanups ]
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NPekka Enberg <penberg@cs.helsinki.fi>

Now that we set up the slab allocator earlier, we can get rid of some
alloc_bootmem_cpumask_var() calls in boot code.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NPekka Enberg <penberg@cs.helsinki.fi>

Fix bug in the SGI UV macros that support systems with multiple
coherency domains.  The macros used for referencing global MMR
(chipset registers) are failing to correctly "or" the NASID
(node identifier) bits that reside above M+N. These high bits
are supplied automatically by the chipset for memory accesses
coming from the processor socket.

However, the bits must be present for references to the special
global MMR space used to map chipset registers. (See uv_hub.h
for more details ...)

The bug results in references to invalid/incorrect nodes.
Signed-off-by: NJack Steiner <steiner@sgi.com>
Cc: <stable@kernel.org>
LKML-Reference: <20090608154405.GA16395@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Ingo Molnar reported that read_apic is buggy novadays:

[    0.000000] Using APIC driver default
[    0.000000] SMP: Allowing 1 CPUs, 0 hotplug CPUs
[    0.000000] Local APIC disabled by BIOS -- you can enable it with "lapic"
[    0.000000] APIC: disable apic facility
[    0.000000] ------------[ cut here ]------------
[    0.000000] WARNING: at arch/x86/kernel/apic/apic.c:254 native_apic_read_dummy+0x2d/0x3b()
[    0.000000] Hardware name: HP OmniBook PC

Indeed we still rely on apic->read operation for SMP compiled
kernel. And instead of disfigure the SMP code with #ifdef we
allow to call apic->read. To capture any unexpected results
we check for apic->read being called for sane reason via
WARN_ON_ONCE but(!) instead of OR we should use AND logical
operation (thanks Yinghai for spotting the root of the problem).

Along with that we could be have bad MP table and we are
to fix it that way no SMP started and no complains about
BIOS bug if apic was just disabled via command line.
Signed-off-by: NCyrill Gorcunov <gorcunov@openvz.org>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <20090607124840.GD4547@lenovo>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

lapic_resume forgets to restore interrupts on fail paths.
Fix that.
Signed-off-by: NJiri Slaby <jirislaby@gmail.com>
Acked-by: NCyrill Gorcunov <gorcunov@openvz.org>
LKML-Reference: <1243497289-18591-1-git-send-email-jirislaby@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>

Fix the fact that the IOAPIC version number in the x86_64 code path always
gets assigned to 0, instead of the correct value.

Before the patch: (from "dmesg" output):

 ACPI: IOAPIC (id[0x08] address[0xfec00000] gsi_base[0])
 IOAPIC[0]: apic_id 8, version 0, address 0xfec00000, GSI 0-23     <---

 After the patch:
 ACPI: IOAPIC (id[0x08] address[0xfec00000] gsi_base[0])
 IOAPIC[0]: apic_id 8, version 32, address 0xfec00000, GSI 0-23    <---

History:

io_apic_get_version() was compiled out of the x86_64 code path in the commit
f2c2cca3:

Author: Andi Kleen <ak@suse.de>
Date:   Tue Sep 26 10:52:37 2006 +0200

    [PATCH] Remove APIC version/cpu capability mpparse checking/printing

    ACPI went to great trouble to get the APIC version and CPU capabilities
    of different CPUs before passing them to the mpparser. But all
    that data was used was to print it out.  Actually it even faked some data
    based on the boot cpu, not on the actual CPU being booted.

    Remove all this code because it's not needed.

    Cc: len.brown@intel.com

At the time, the IOAPIC version number was deliberately not printed
in the x86_64 code path. However, after the x86 and x86_64 files were
merged, the net result is that the IOAPIC version is printed incorrectly
in the x86_64 code path.

The patch below provides a fix. I have tested it with acpi, and with
acpi=off, and did not see any problems.
Signed-off-by: NNaga Chumbalkar <nagananda.chumbalkar@hp.com>
Acked-by: NYinghai Lu <yhlu.kernel@gmail.com>
LKML-Reference: <20090416014230.4885.94926.sendpatchset@localhost.localdomain>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
*************************

Always use NMI for performance-monitoring interrupt as there could be
racy situations if we switch between irq and nmi mode frequently.
Signed-off-by: NYong Wang <yong.y.wang@intel.com>
LKML-Reference: <20090529052835.GA13657@ywang-moblin2.bj.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The 64bit machine check code is in many ways much better than
the 32bit machine check code: it is more specification compliant,
is cleaner, only has a single code base versus one per CPU,
has better infrastructure for recovery, has a cleaner way to communicate
with user space etc. etc.

Use the 64bit code for 32bit too.

This is the second attempt to do this. There was one a couple of years
ago to unify this code for 32bit and 64bit.  Back then this ran into some
trouble with K7s and was reverted.

I believe this time the K7 problems (and some others) are addressed.
I went over the old handlers and was very careful to retain
all quirks.

But of course this needs a lot of testing on old systems. On newer
64bit capable systems I don't expect much problems because they have been
already tested with the 64bit kernel.

I made this a CONFIG for now that still allows to select the old
machine check code. This is mostly to make testing easier,
if someone runs into a problem we can ask them to try
with the CONFIG switched.

The new code is default y for more coverage.

Once there is confidence the 64bit code works well on older hardware
too the CONFIG_X86_OLD_MCE and the associated code can be easily
removed.

This causes a behaviour change for 32bit installations. They now
have to install the mcelog package to be able to log
corrected machine checks.

The 64bit machine check code only handles CPUs which support the
standard Intel machine check architecture described in the IA32 SDM.
The 32bit code has special support for some older CPUs which
have non standard machine check architectures, in particular
WinChip C3 and Intel P5.  I made those a separate CONFIG option
and kept them for now. The WinChip variant could be probably
removed without too much pain, it doesn't really do anything
interesting. P5 is also disabled by default (like it
was before) because many motherboards have it miswired, but
according to Alan Cox a few embedded setups use that one.

Forward ported/heavily changed version of old patch, original patch
included review/fixes from Thomas Gleixner, Bert Wesarg.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

remove the x86 specific interrupt throttle
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090525153931.616671838@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This replaces the struct perf_counter_context in the task_struct with
a pointer to a dynamically allocated perf_counter_context struct.  The
main reason for doing is this is to allow us to transfer a
perf_counter_context from one task to another when we do lazy PMU
switching in a later patch.

This has a few side-benefits: the task_struct becomes a little smaller,
we save some memory because only tasks that have perf_counters attached
get a perf_counter_context allocated for them, and we can remove the
inclusion of <linux/perf_counter.h> in sched.h, meaning that we don't
end up recompiling nearly everything whenever perf_counter.h changes.

The perf_counter_context structures are reference-counted and freed
when the last reference is dropped.  A context can have references
from its task and the counters on its task.  Counters can outlive the
task so it is possible that a context will be freed well after its
task has exited.

Contexts are allocated on fork if the parent had a context, or
otherwise the first time that a per-task counter is created on a task.
In the latter case, we set the context pointer in the task struct
locklessly using an atomic compare-and-exchange operation in case we
raced with some other task in creating a context for the subject task.

This also removes the task pointer from the perf_counter struct.  The
task pointer was not used anywhere and would make it harder to move a
context from one task to another.  Anything that needed to know which
task a counter was attached to was already using counter->ctx->task.

The __perf_counter_init_context function moves up in perf_counter.c
so that it can be called from find_get_context, and now initializes
the refcount, but is otherwise unchanged.

We were potentially calling list_del_counter twice: once from
__perf_counter_exit_task when the task exits and once from
__perf_counter_remove_from_context when the counter's fd gets closed.
This adds a check in list_del_counter so it doesn't do anything if
the counter has already been removed from the lists.

Since perf_counter_task_sched_in doesn't do anything if the task doesn't
have a context, and leaves cpuctx->task_ctx = NULL, this adds code to
__perf_install_in_context to set cpuctx->task_ctx if necessary, i.e. in
the case where the current task adds the first counter to itself and
thus creates a context for itself.

This also adds similar code to __perf_counter_enable to handle a
similar situation which can arise when the counters have been disabled
using prctl; that also leaves cpuctx->task_ctx = NULL.

[ Impact: refactor counter context management to prepare for new feature ]
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <18966.10075.781053.231153@cargo.ozlabs.ibm.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Peter bisected that:

| commit b9c61b70
| Date:   Wed May 6 10:10:06 2009 -0700
|
|     x86/pci: update pirq_enable_irq() to setup io apic routing
|
|     So we can set io apic routing only when enabling the device irq.

wrecked his opteron box, ata1 interrupts fail to get through.

ata1 is using irq 11:

[    1.451839] sata_svw 0000:01:0e.0: version 2.3
[    1.456333] sata_svw 0000:01:0e.0: PCI INT A -> GSI 11 (level, low) -> IRQ 11
[    1.463639] scsi0 : sata_svw
[    1.466949] scsi1 : sata_svw
[    1.470022] scsi2 : sata_svw
[    1.473090] scsi3 : sata_svw
[    1.476112] ata1: SATA max UDMA/133 mmio m8192@0xff3fe000 port 0xff3fe000 irq 11
[    1.483490] ata2: SATA max UDMA/133 mmio m8192@0xff3fe000 port 0xff3fe100 irq 11
[    1.490870] ata3: SATA max UDMA/133 mmio m8192@0xff3fe000 port 0xff3fe200 irq 11
[    1.498247] ata4: SATA max UDMA/133 mmio m8192@0xff3fe000 port 0xff3fe300 irq 11

that pin is overlapped with pin with legacy ones.

We should not set bits in pin_programmed here, so that those bit could
be set later via io_apic_set_pci_routing().

[ Impact: fix boot hang on certain systems ]
Reported-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NYinghai Lu <yinghai.lu@kernel.org>
Tested-by: NPeter Zijlstra <peterz@infradead.org>
Cc: Jack Steiner <steiner@sgi.com>
LKML-Reference: <4A119990.9020606@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

should not call that if apic is disabled.

[ Impact: fix crash on certain UP configs ]
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
LKML-Reference: <4A09CCBB.2000306@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

according to Ingo, io_apic irq-setup related functions have too many
parameters with a repetitive signature.

So reduce related funcs to get less params by passing a pointer
to a newly defined io_apic_irq_attr structure.

v2: io_apic_irq ==> irq_attr
    triggering ==> trigger

v3: add set_io_apic_irq_attr

[ Impact: cleanup ]
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <4A08ACD3.2070401@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

* Arun R Bharadwaj <arun@linux.vnet.ibm.com> [2009-04-16 12:11:36]:

The following pinned hrtimers have been identified and marked:
1)sched_rt_period_timer
2)tick_sched_timer
3)stack_trace_timer_fn

[ tglx: fixup the hrtimer pinned mode ]
Signed-off-by: NArun R Bharadwaj <arun@linux.vnet.ibm.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Ed found that on 32-bit, boot_cpu_physical_apicid is not read right,
when the mptable is broken.

Interestingly, actually three paths use/set it:

 1. acpi: at that time that is already read from reg
 2. mptable: only read from mptable
 3. no madt, and no mptable, that use default apic id 0 for 64-bit, -1 for 32-bit

so we could read the apic id for the 2/3 path. We trust the hardware
register more than we trust a BIOS data structure (the mptable).

We can also avoid the double set_fixmap() when acpi_lapic
is used, and also need to move cpu_has_apic earlier and
call apic_disable().

Also when need to update the apic id, we'd better read and
set the apic version as well - so that quirks are applied precisely.

v2: make path 3 with 64bit, use -1 as apic id, so could read it later.
v3: fix whitespace problem pointed out by Ed Swierk
v5: fix boot crash

[ Impact: get correct apic id for bsp other than acpi path ]
Reported-by: NEd Swierk <eswierk@aristanetworks.com>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Acked-by: NCyrill Gorcunov <gorcunov@openvz.org>
LKML-Reference: <49FC85A9.2070702@kernel.org>
[ v4: sanity-check in the ACPI case too ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>

In case if apic were disabled by boot option
we still need read_apic operation. So fixmap
a fake apic area if needed.

[ Impact: fix boot crash ]
Signed-off-by: NCyrill Gorcunov <gorcunov@openvz.org>
Cc: yinghai@kernel.org
Cc: eswierk@aristanetworks.com
LKML-Reference: <20090511134140.GH4624@lenovo>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Both print_local_APIC (used when apic=debug kernel param is set) and
cpu_debug code missed support for some extended APIC registers that
I'd like to see.

This adds support to show:

 - extended APIC feature register
 - extended APIC control register
 - extended LVT registers

[ Impact: print more debug info ]
Signed-off-by: NAndreas Herrmann <andreas.herrmann3@amd.com>
Cc: Jaswinder Singh Rajput <jaswinder@kernel.org>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
LKML-Reference: <20090508162350.GO29045@alberich.amd.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Ed found that on 32-bit, boot_cpu_physical_apicid is not read right,
when the mptable is broken.

Interestingly, actually three paths use/set it:

 1. acpi: at that time that is already read from reg
 2. mptable: only read from mptable
 3. no madt, and no mptable, that use default apic id 0 for 64-bit, -1 for 32-bit

so we could read the apic id for the 2/3 path. We trust the hardware
register more than we trust a BIOS data structure (the mptable).

We can also avoid the double set_fixmap() when acpi_lapic
is used, and also need to move cpu_has_apic earlier and
call apic_disable().

Also when need to update the apic id, we'd better read and
set the apic version as well - so that quirks are applied precisely.

v2: make path 3 with 64bit, use -1 as apic id, so could read it later.
v3: fix whitespace problem pointed out by Ed Swierk

[ Impact: get correct apic id for bsp other than acpi path ]
Reported-by: NEd Swierk <eswierk@aristanetworks.com>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Acked-by: NCyrill Gorcunov <gorcunov@openvz.org>
LKML-Reference: <49FC85A9.2070702@kernel.org>
[ v4: sanity-check in the ACPI case too ]
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: fix fadt version checking

FADT2_REVISION_ID has value 3 aka rev 3 FADT. So need to use >= instead
of >, as other places in the code do.

[ Impact: extend scope of APIC boot quirk ]
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
LKML-Reference: <new-submission>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

So we can set io apic routing only when enabling the device irq.

This is advantageous for IRQ descriptor allocation affinity: if we set up
the IO-APIC entry later, we have a chance to allocate the IRQ descriptor
later and know which device it is on and can set affinity accordingly.

[ Impact: standardize/enhance irq-enabling sequence for mptable irqs ]
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A01C46E.8000501@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

So we could set io apic routing when ACPI is not enabled.

[ Impact: prepare for new functionality ]
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <4A01C422.5070400@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

To prepare those params for pcibios_irq_enable() to call setup_io_apic_routing().

[ Impact: extend function call API to prepare for new functionality ]
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A01C406.2040303@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>