litmus-rt.git/include/asm-x86_64, branch linux-tip

i386/x86_64: move headers to include/asm-x86

2007-10-11T09:20:03+00:00

Move the headers to include/asm-x86 and fixup the
header install make rules

Signed-off-by: Thomas Gleixner 
Signed-off-by: Ingo Molnar

x86_64: remove unused header file:

2007-10-11T09:11:39+00:00

Signed-off-by: Thomas Gleixner 
Signed-off-by: Ingo Molnar

Remove unnecessary cast in prefetch()

2007-10-05T15:04:35+00:00

It is ok to call prefetch() function with NULL argument, as specifically
commented in include/linux/prefetch.h.  But in standard C, it is invalid
to dereference NULL pointer (see C99 standard 6.5.3.2 paragraph 4 and
note #84).

prefetch() has a memory reference for its argument.

Newer gcc versions (4.3 and above) will use that to conclude that "x"
argument is non-null and thus wreaking havok everywhere prefetch() was
inlined.

Fixed by removing cast and changing asm constraint.

[ It seems in theory gcc 4.2 could miscompile this too; although no
  cases known.  In 2.6.24 we should probably switch to
  __builtin_prefetch() instead, but this is a simpler fix for now.
				-- AK ]

Signed-off-by: Serge Belyshev 
Signed-off-by: Andi Kleen 
Signed-off-by: Linus Torvalds

Revert "x86-64: Disable local APIC timer use on AMD systems with C1E"

2007-09-26T22:43:41+00:00

This reverts commit e66485d747505e9d960b864fc6c37f8b2afafaf0, since
Rafael Wysocki noticed that the change only works for his in -mm, not in
mainline (and that both "noapictimer" _and_ "apicmaintimer" are broken
on his hardware, but that's apparently not a regression, just a symptom
of the same issue that causes the automatic apic timer disable to not
work).

It turns out that it really doesn't work correctly on x86-64, since
x86-64 doesn't use the generic clock events for timers yet.

Thanks to Rafal for testing, and here's the ugly details on x86-64 as
per Thomas:

  "I just looked into the code and the logic vs.  noapictimer on SMP is
   completely broken.

   On i386 the noapictimer option not only disables the local APIC
   timer, it also registers the CPUs for broadcasting via IPI on SMP
   systems.

   The x86-64 code uses the broadcast only when the local apic timer is
   active, i.e.  "noapictimer" is not on the command line.  This defeats
   the whole purpose of "noapictimer".  It should be there to make boxen
   work, where the local APIC timer actually has a hardware problem,
   e.g.  the nx6325.

   The current implementation of x86_64 only fixes the ACPI c-states
   related problem where the APIC timer stops in C3(2), nothing else.

   On nx6325 and other AMD X2 equipped systems which have the C1E
   enabled we run into the following:

   PIT keeps jiffies (and the system) running, but the local APIC timer
   interrupts can get out of sync due to this C1E effect.

   I don't think this is a critical problem, but it is wrong
   nevertheless.

   I think it's safe to revert the C1E patch and postpone the fix to the
   clock events conversion."

On further reflection, Thomas noted:

   "It's even worse than I thought on the first check:

    "noapictimer" on the command line of an SMP box prevents _ONLY_ the
    boot CPU apic timer from being used.  But the secondary CPU is still
    unconditionally setting up the APIC timer and uses the non
    calibrated variable calibration_result, which is of course 0, to
    setup the APIC timer.  Wreckage guaranteed."

so we'll just have to wait for the x86 merge to hopefully fix this up
for x86-64.

Tested-and-requested-by: Rafael J. Wysocki 
Acked-by: Thomas Gleixner 
Signed-off-by: Linus Torvalds

x86-64: Disable local APIC timer use on AMD systems with C1E

2007-09-26T16:22:04+00:00

commit 3556ddfa9284a86a59a9b78fe5894430f6ab4eef titled

 [PATCH] x86-64: Disable local APIC timer use on AMD systems with C1E

solves a problem with AMD dual core laptops e.g. HP nx6325 (Turion 64
X2) with C1E enabled:

When both cores go into idle at the same time, then the system switches
into C1E state, which is basically the same as C3. This stops the local
apic timer.

This was debugged right after the dyntick merge on i386 and despite the
patch title it fixes only the 32 bit path.

x86_64 is still missing this fix. It seems that mainline is not really
affected by this issue, as the PIT is running and keeps jiffies
incrementing, but that's just waiting for trouble.

-mm suffers from this problem due to the x86_64 high resolution timer
patches.

This is a quick and dirty port of the i386 code to x86_64.

I spent quite a time with Rafael to debug the -mm / hrt wreckage until
someone pointed us to this. I really had forgotten that we debugged this
half a year ago already.

Sigh, is it just me or is there something yelling arch/x86 into my ear?

Signed-off-by: Thomas Gleixner 
Tested-by: Rafael J. Wysocki 
Signed-off-by: Linus Torvalds

Revert "x86_64: Quicklist support for x86_64"

2007-09-21T19:09:41+00:00

This reverts commit 34feb2c83beb3bdf13535a36770f7e50b47ef299.

Suresh Siddha points out that this one breaks the fundamental
requirement that you cannot free page table pages before the TLB caches
are flushed.  The quicklists do not give the same kinds of guarantees
that the mmu_gather structure does, at least not in NUMA configurations.

Requested-by: Suresh Siddha 
Acked-by: Andi Kleen 
Cc: Andrew Morton 
Cc: Christoph Lameter 
Cc: Asit Mallick 
Cc: Tony Luck 
Signed-off-by: Linus Torvalds

Pull bugzilla-1641 into release branch

2007-08-25T02:19:05+00:00

ACPI: boot correctly with "nosmp" or "maxcpus=0"

2007-08-21T04:33:35+00:00

In MPS mode, "nosmp" and "maxcpus=0" boot a UP kernel with IOAPIC disabled.
However, in ACPI mode, these parameters didn't completely disable
the IO APIC initialization code and boot failed.

init/main.c:
	Disable the IO_APIC if "nosmp" or "maxcpus=0"
	undefine disable_ioapic_setup() when it doesn't apply.

i386:
	delete ioapic_setup(), it was a duplicate of parse_noapic()
	delete undefinition of disable_ioapic_setup()

x86_64:
	rename disable_ioapic_setup() to parse_noapic() to match i386
	define disable_ioapic_setup() in header to match i386

http://bugzilla.kernel.org/show_bug.cgi?id=1641

Acked-by: Andi Kleen 
Signed-off-by: Len Brown

x86_64: Fix to keep watchdog disabled by default for i386/x86_64

2007-08-18T17:25:25+00:00

Fixed wrong expression which enabled watchdogs even if nmi_watchdog kernel
parameter wasn't set. This regression got slightly introduced with commit
b7471c6da94d30d3deadc55986cc38d1ff57f9ca.

Introduced NMI_DISABLED (-1) which allows to switch the value of NMI_DEFAULT
without breaking the APIC NMI watchdog code (again).

Fixes:
   https://bugzilla.novell.com/show_bug.cgi?id=298084
   http://bugzilla.kernel.org/show_bug.cgi?id=7839
And likely some more nmi_watchdog=0 related issues.

Signed-off-by: Daniel Gollub 
Signed-off-by: Andi Kleen 
Signed-off-by: Linus Torvalds

finish i386 and x86-64 sysdata conversion

2007-08-11T22:47:42+00:00

This patch finishes the i386 and x86-64 ->sysdata conversion and hopefully
also fixes Riku's and Andy's observed bugs.  It is based on Yinghai Lu's
and Andy Whitcroft's patches (thanks!) with some changes:

- introduce pci_scan_bus_with_sysdata() and use it instead of
  pci_scan_bus() where appropriate. pci_scan_bus_with_sysdata() will
  allocate the sysdata structure and then call pci_scan_bus().
- always allocate pci_sysdata dynamically. The whole point of this
  sysdata work is to make it easy to do root-bus specific things
  (e.g., support PCI domains and IOMMU's). I dislike using a default
  struct pci_sysdata in some places and a dynamically allocated
  pci_sysdata elsewhere - the potential for someone indavertantly
  changing the default structure is too high.
- this patch only makes the minimal changes necessary, i.e., the NUMA node is
  always initialized to -1. Patches to do the right thing with regards
  to the NUMA node can build on top of this (either add a 'node'
  parameter to pci_scan_bus_with_sysdata() or just update the node
  when it becomes known).

The patch was compile tested with various configurations (e.g., NUMAQ,
VISWS) and run-time tested on i386 and x86-64.  Unfortunately none of my
machines exhibited the bugs so caveat emptor.

Andy, could you please see if this fixes the NUMA issues you've seen?
Riku, does this fix "pci=noacpi" on your laptop?

Signed-off-by: Muli Ben-Yehuda 
Cc: Yinghai Lu 
Cc: Andi Kleen 
Cc: Chuck Ebbert 
Cc: 
Cc: Andy Whitcroft 
Cc: Jeff Garzik 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds