Commit graph

327 commits

Author SHA1 Message Date
Adrian Bunk
f1aa14b2e9 x86: kernel/setup_32.c: unexport machine_id
This patch removes the unused EXPORT_SYMBOL(machine_id).

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-30 00:22:22 +01:00
Joerg Roedel
0440d4c00d x86 gart: rename symbols only used for the GART implementation
This patch renames the 4 symbols iommu_hole_init(), iommu_aperture,
iommu_aperture_allowed, iommu_aperture_disabled. All these symbols are only
used for the GART implementation of IOMMUs.

It adds and additional gart_ prefix to them.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-30 00:22:22 +01:00
Joerg Roedel
79da087441 x86 gart: make some variables and functions static
This patch makes some functions and variables static in pci-gart_64.c which are
not used somewhere else.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Muli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-30 00:22:22 +01:00
Joerg Roedel
966396d3a0 x86 gart: rename CONFIG_IOMMU to CONFIG_GART_IOMMU
This patch renames the IOMMU config option to GART_IOMMU because in fact it
means the GART and not general support for an IOMMU on x86.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Muli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-30 00:22:22 +01:00
Joerg Roedel
395624fcdd x86 gart: rename iommu.h to gart.h
This patch renames the include file asm-x86/iommu.h to asm-x86/gart.h to make
clear to which IOMMU implementation it belongs. The patch also adds "GART" to
the Kconfig line.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Muli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-30 00:22:22 +01:00
H. Peter Anvin
e1054b39b2 x86: additional CPUID strings; fix strings for AMD-ecx
Additional CPUID strings (sse4_1, sse4_2, sse5, skinit, wdt); fix the
positioning of the AMD ecx strings (cr8_legacy was duplicated under
two different names, so the alignment of all the other strings were
off by one.)

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-30 00:22:22 +01:00
Linus Torvalds
6a22c57b8d Revert "x86_64: allocate sparsemem memmap above 4G"
This reverts commit 2e1c49db4c.

First off, testing in Fedora has shown it to cause boot failures,
bisected down by Martin Ebourne, and reported by Dave Jobes.  So the
commit will likely be reverted in the 2.6.23 stable kernels.

Secondly, in the 2.6.24 model, x86-64 has now grown support for
SPARSEMEM_VMEMMAP, which disables the relevant code anyway, so while the
bug is not visible any more, it's become invisible due to the code just
being irrelevant and no longer enabled on the only architecture that
this ever affected.

Reported-by: Dave Jones <davej@redhat.com>
Tested-by: Martin Ebourne <fedora@ebourne.me.uk>
Cc: Zou Nan hai <nanhai.zou@intel.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-29 14:05:37 -07:00
FUJITA Tomonori
5336940dd8 x86: fix pci-gart failure handling
blk_rq_map_sg doesn't initialize sg->dma_address/length to zero
anymore. Some low level drivers reuse sg lists without initializing so
IOMMUs might get non-zero dma_address/length. If map_sg fails, we need
pass the number of the mapped entries to gart_unmap_sg.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-29 09:18:03 +01:00
Ken'ichi Ohmichi
69243f9125 x86: Dump filtering supports x86_64 sparsemem
This patch adds the symbol "init_level4_pgt" to the vmcoreinfo data so
that makedumpfile (dump filtering command) supports x86_64 sparsemem 
kernel of linux-2.6.24.

makedumpfile creates a small dumpfile by excluding unnecessary pages for
the analysis. It checks attributes in page structures and distinguishes
necessary pages and unnecessary ones. To check them, makedumpfile gets
the vmcoreinfo data which has the minimum debugging information only for
dump filtering.

For older x86_64 kernel (linux-2.6.23 or before), makedumpfile translates
the virtual address of page structure into physical address by subtracting
PAGE_OFFSET from virtual address, but this translation isn't effective for
linux-2.6.24 sparsemem kernel, because its page structures are in virtual
memmap area. makedumpfile should translate their virtual address by 4-levels
paging and it needs the symbol "init_level4_pgt".

Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-27 20:57:43 +02:00
Jeff Garzik
03d0d20e64 x86: fix compiler warnings in arch/x86/kernel/early-quirks.c
fix this warning:

arch/x86/kernel/early-quirks.c:40: warning: nvidia_hpet_check defined but not used

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-27 20:57:43 +02:00
Jeff Garzik
74a3d2d331 x86: fix !SMP compiler warning in arch/x86/kernel/acpi/processor.c
Fix !CONFIG_SMP warning:

arch/x86/kernel/acpi/processor.c: In function arch_acpi_processor_init_pdc:
arch/x86/kernel/acpi/processor.c:65: warning: unused variable cpu

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-27 20:57:43 +02:00
Eric W. Biederman
bd53147db8 x86: Fix boot protocol KEEP_SEGMENTS check.
The kernel only ever supports 1 version of the boot protocol
so there is no need to check the boot protocol revision to
see if a feature is supported.

Both x86 and x86_64 support the same boot protocol so we need
to implement the KEEP_SEGMENTS on x86_64 as well.  It isn't
just paravirt bootloaders that could use this functionality.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Zachary Amsden <zach@vmware.com>
Cc: Andi Kleen <ak@suse.de>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-27 20:57:43 +02:00
James Bottomley
0cca1ca647 x86: voyager: fix bogus conversion to per_cpu for boot_cpu_info
There were two problems.  Firstly, someone forgot the struct keyword in
front of cpuinfo_x86, so I take it this wasn't even compile checked.
Secondly, the actual definition has this as a SHARED_ALIGNED, so the
definitions mismatch.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-27 20:57:43 +02:00
Thomas Gleixner
027447c491 x86: export smp_ops to allow modular build of KVM
KVM uses smp_call_function_mask and therefor need smp_ops to be exported.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-27 20:57:43 +02:00
Thomas Gleixner
ceff8d859c Revert "i386: export i386 smp_call_function_mask() to modules"
This reverts commit 6442eea937.

The patch breaks smp_ops and needs to be reverted. The solution to
allow modular build of KVM is to export smp_ops instead.

Pointed-out-by: James Bottomley

  <jejb> tglx, so write out 100 times "voyager is a useful architecture" ...
  <tglx> yes, Sir

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-27 20:57:43 +02:00
Linus Torvalds
26adc0d585 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hpa/linux-2.6-x86setup
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hpa/linux-2.6-x86setup:
  x86 setup: sizeof() is unsigned, unbreak comparisons
  x86 setup: handle boot loaders which set up the stack incorrectly
2007-10-26 13:56:01 -07:00
Linus Torvalds
0e4bd10c9b Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/x86
* git://git.kernel.org/pub/scm/linux/kernel/git/sam/x86:
  x86: kill the old i386 and x86_64 directories
  x86: move i386 and x86_64 Kconfig files to x86 directory
  kconfig: small code refactoring in kconfig Makefile
  x86: unification of i386 and x86_64 Kconfig.debug
  x86: move defconfig files for i386 and x86_64 to x86
  x86: move i386 and x86_64 Makefiles to arch/x86
2007-10-26 13:49:29 -07:00
H. Peter Anvin
e6e1ace990 x86 setup: sizeof() is unsigned, unbreak comparisons
We use signed values for limit checking since the values can go
negative under certain circumstances.  However, sizeof() is unsigned
and forces the comparison to be unsigned, so move the comparison into
the heap_free() macros so we can ensure it is a signed comparison.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2007-10-25 20:20:06 -07:00
H. Peter Anvin
6b6815c6d5 x86 setup: handle boot loaders which set up the stack incorrectly
Apparently some specific versions of LILO enter the kernel with a
stack pointer that doesn't match the rest of the segments.  Make our
best attempt at untangling the resulting mess.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2007-10-25 19:55:03 -07:00
Linus Torvalds
22fa8d59be Merge git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86
* git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86:
  x86: fix bogus KERN_ALERT on oops
  x86: lguest build fix
  x86: fix CONFIG_KEXEC build breakage
2007-10-25 15:48:05 -07:00
Linus Torvalds
7f14957453 Merge branch 'sg' of git://git.kernel.dk/linux-2.6-block
* 'sg' of git://git.kernel.dk/linux-2.6-block:
  fix sg_phys to use dma_addr_t
  ub: add sg_init_table for sense and read capacity commands
  x86: pci-gart fix
  blackfin: fix sg fallout
  xtensa: dma-mapping.h is using linux/scatterlist.h functions, so include it
  SG: audit of drivers that use blk_rq_map_sg()
  arch/um/drivers/ubd_kern.c: fix a building error
  SG: Change sg_set_page() to take length and offset argument
  AVR32: Fix sg_page breakage
  mmc: sg fallout
  m68k: sg fallout
  More SG build fixes
  sg: add missing sg_init_table calls to zfcp
  SG build fix
2007-10-25 15:44:54 -07:00
Sam Ravnborg
47572387d5 x86: move i386 and x86_64 Kconfig files to x86 directory
After a small change in kconfig Makefile we could
move all x86 Kconfig files to x86 directory.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-10-25 22:37:02 +02:00
Randy Dunlap
d013a27cb7 x86: unification of i386 and x86_64 Kconfig.debug
Adding proper dependencies so the two Kconfig.debug files
are now identical and move the result file to x86.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-10-25 22:35:10 +02:00
Sam Ravnborg
2266cfd50d x86: move defconfig files for i386 and x86_64 to x86
With some small changes to kconfig makefile we can now
locate the defconfig files for i386 and x86_64 in
the configs/ subdirectory under x86.
make ARCH=i386 defconfig and make defconfig
works as expected also after this change.
But arch maintainers shall now update a defconfig file in
the configs/ directory.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-10-25 22:27:41 +02:00
Sam Ravnborg
74b469f2e6 x86: move i386 and x86_64 Makefiles to arch/x86
Moving the ARCH specific Makefiles for i386 and x86_64
required a litle bit tweaking in the top-lvel Makefile.

SRCARCH is now set in the top-level Makefile
because we need this info to include the correct
arch Makefile.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-10-25 22:27:34 +02:00
FUJITA Tomonori
e88a39dee1 x86: pci-gart fix
map_sg could copy the last sg element to another position (if merging
some elements). It breaks sg chaining. This copies only
dma_address/length instead of the whole sg element.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-25 09:13:32 +02:00
Rusty Russell
e1e72965ec lguest: documentation update
Went through the documentation doing typo and content fixes.  This
patch contains only comment and whitespace changes.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-25 15:02:50 +10:00
Jeff Garzik
4cfe6c3c1c lguest: build fix
Fix this error (i386 !SMP build)

arch/x86/lguest/boot.c: In function ‘lguest_init’:
arch/x86/lguest/boot.c:1059: error: ‘pm_power_off’ undeclared (first use in this function)

by including linux/pm.h.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-25 14:15:09 +10:00
Rusty Russell
25c47bb353 lguest: use defines from x86 headers instead of magic numbers
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-10-25 14:09:53 +10:00
Alexey Dobriyan
eec407c9ac x86: fix bogus KERN_ALERT on oops
fix this:

printing eip: f881b9f3 *pdpt = 0000000000003001 <1>*pde = 000000000480a067 *pte = 0000000000000000
						^^^

[ mingo: added KERN_CONT as suggested by Pekka Enberg ]

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-24 12:58:02 +02:00
Jeff Garzik
230e55adf6 x86: lguest build fix
Fix this error (i386 !SMP build):

arch/x86/lguest/boot.c: In function lguest_init:
arch/x86/lguest/boot.c:1059: error: pm_power_off undeclared (first use in this function)

by including linux/pm.h.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-24 12:58:02 +02:00
Mike Galbraith
1fb473d8f4 x86: fix CONFIG_KEXEC build breakage
X86_32 build fix to commit 62a31a03b3

Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-24 12:58:01 +02:00
Linus Torvalds
25c263542d Merge branch 'irq-upstream' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/misc-2.6
* 'irq-upstream' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/misc-2.6:
  [SPARC, XEN, NET/CXGB3] use irq_handler_t where appropriate
  drivers/char/riscom8: clean up irq handling
  isdn/sc: irq handler clean
  isdn/act2000: fix major bug. clean irq handler.
  char/pcmcia/synclink_cs: trim trailing whitespace
  drivers/char/ip2: separate polling and irq-driven work entry points
  drivers/char/ip2: split out irq core logic into separate function
  [NETDRVR] lib82596, netxen: delete pointless tests from irq handler
  Eliminate pointless casts from void* in a few driver irq handlers.
  [PARPORT] Remove unused 'irq' argument from parport irq functions
  [PARPORT] Kill useful 'irq' arg from parport_{generic_irq,ieee1284_interrupt}
  [PARPORT] Consolidate code copies into a single generic irq handler
2007-10-23 18:57:39 -07:00
Jeff Garzik
7c2399756a [SPARC, XEN, NET/CXGB3] use irq_handler_t where appropriate
Rather than hand-rolling our own prototype, make the code more
future-proof by using the standard irq_handler_t typedef.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2007-10-23 19:53:17 -04:00
Carlos Corbacho
1b82ba6e47 x86: Add HPET force support for MCP55 (nForce 5) chipsets
Add support to force_hpet for all known MCP55 (nForce 5) chipset
LPC bridges.

These are the untested nForce 5 chips (taken from Mikko's original 
patch, and checked against pci.ids).

Signed-off-by: Carlos Corbacho <cathectic@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

 arch/x86/kernel/quirks.c |   18 ++++++++++++++++++
 1 file changed, 18 insertions(+)
2007-10-23 22:37:25 +02:00
Carlos Corbacho
d79a5f80dc x86: Force enable HPET for CK804 (nForce 4) chipsets
This patch adds a quirk from LinuxBIOS to force enable HPET on
the nVidia CK804 (nForce 4) chipset.

This quirk can very likely support more than just nForce 4
(LinuxBIOS use the same code for nForce 5), and possibly nForce 3,
but I don't have those chipsets, so cannot add and test them.

Tested on an Abit KN9 (CK804).

Signed-off-by: Carlos Corbacho <cathectic@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

 Documentation/kernel-parameters.txt |    3 +-
 arch/x86/kernel/quirks.c            |   37 +++++++++++++++++++++++++++++++++++-
 2 files changed, 38 insertions(+), 2 deletions(-)
2007-10-23 22:37:25 +02:00
H. Peter Anvin
fa76dab935 x86: clean up setup.h and the boot code
Make <asm/setup.h> usable by the boot code.

Clean up vestiges of the old command-line protocol from setup.h and
head_32.S (it is still supported from the boot loader point of
view, since it is converted to the new command-line protocol by the
boot code.)

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-23 22:37:25 +02:00
Rafael J. Wysocki
0de80bcc2b x86: Save registers in saved_context during suspend and hibernation
During hibernation and suspend on x86_64 save CPU registers in the saved_context
structure rather than in a handful of separate variables.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-23 22:37:24 +02:00
Thomas Gleixner
d88203d1ab x86: whitespace cleanup of mce_64.c
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-23 22:37:23 +02:00
Thomas Gleixner
01e11182e7 x86: consolidate the cpu/ related code usage
The x86_64 arch/x86/kernel/Makefile uses references into 
arch/x86/kernel/cpu/... to use code from there.

Unifiy it with the nicely structured i386 way and reuse the existing
subdirectory make rules.

Also move the machine check related source into ...kernel/cpu/mcheck,
where the other machine check related code is.

No code change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-23 22:37:23 +02:00
Thomas Gleixner
3bc258ad87 x86: prepare consolidation of cpu/ related code usage
Move mce.c to mce_32.c to allow the later move of the x86_64 mce.c
from arch/x86/kernel/ to ...kernel/cpu/mcheck

No code change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-23 22:37:23 +02:00
Thomas Gleixner
34d19e29c9 x86: prepare consolidation of cpu/ related Makefiles
Prepare the makefiles in x86/kernel/cpu and x86/kernel/cpu/mcheck to
be used by the x86_64 build as well.

No code change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-23 22:37:23 +02:00
Thomas Gleixner
5e4181b313 x86: Unify arch/x86/kernel/acpi Makefiles
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-23 22:37:23 +02:00
Thomas Gleixner
9b58aebc73 x86: merge arch/x86/crypto Makefiles
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-23 22:37:23 +02:00
Hiroshi Shimamoto
62a31a03b3 x86: unify crash_32/64.c
Most of contents in crash are same.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-23 22:37:23 +02:00
Hiroshi Shimamoto
9b7711f083 x86: add lapic_shutdown for x86_64
Preperatory patch to allow crash_32/64.c merging

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-23 22:37:22 +02:00
Alejandro Martinez Ruiz
4d022adab4 x86: ARRAY_SIZE cleanup
Signed-off-by: Alejandro Martinez Ruiz <alex@flawedcode.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-23 22:37:22 +02:00
Dave Johnson
8c66006538 x86: fix more TSC clock source calibration errors
The previous patch wasn't correctly handling the 'count' variable.  If
a CPU gave bad results on the 1st or 2nd run but good results on the
3rd, it wouldn't do the correct thing.  No idea if any such CPU
exists, but the patch below handles that case by discarding the bad
runs.

If a bad result (too quick, or too slow) occurs on any of the 3 runs
it will be discarded.

Also updated some comments to explain what's going on.

Signed-off-by: Dave Johnson <djohnson@sw.starentnetworks.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-23 22:37:22 +02:00
Dave Johnson
edaf420fdc x86: fix TSC clock source calibration error
I ran into this problem on a system that was unable to obtain NTP sync
because the clock was running very slow (over 10000ppm slow). ntpd had
declared all of its peers 'reject' with 'peer_dist' reason.

On investigation, the tsc_khz variable was significantly incorrect
causing xtime to run slow.  After a reboot tsc_khz was correct so I
did a reboot test to see how often the problem occurred:

Test was done on a 2000 Mhz Xeon system.  Of 689 reboots, 8 of them
had unacceptable tsc_khz values (>500ppm):

 range of tsc_khz  # of boots  % of boots
 ----------------  ----------  ----------
        < 1999750           0      0.000%
1999750 - 1999800          21      3.048%
1999800 - 1999850         166     24.128%
1999850 - 1999900         241     35.029%
1999900 - 1999950         211     30.669%
1999950 - 2000000          42      6.105%
2000000 - 2000000           0      0.000%
2000050 - 2000100           0      0.000%
                   [...]
2000100 - 2015000           1      0.145%  << BAD
2015000 - 2030000           6      0.872%  << BAD
2030000 - 2045000           1      0.145%  << BAD
2045000 <                   0      0.000%

The worst boot was 2032.577 Mhz, over 1.5% off!

It appears that on rare occasions, mach_countup() is taking longer to
complete than necessary.

I suspect that this is caused by the CPU taking a periodic SMI
interrupt right at the end of the 30ms calibration loop.  This would
cause the loop to delay while the SMI BIOS hander runs. The resulting
TSC value is beyond what it actually should be resulting in a higher
tsc_khz.

The below patch makes native_calculate_cpu_khz() take the best
(shortest duration, lowest khz) run of it's 3 calibration loops.  If a
SMI goes off causing a bad result (long duration, higher khz) it will
be discarded.

With the patch applied, 300 boots of the same system produce good
results:

 range of tsc_khz  # of boots  % of boots
 ----------------  ----------  ----------
        < 1999750           0      0.000%
1999750 - 1999800          30     10.000%
1999800 - 1999850         166     55.333%
1999850 - 1999900          89     29.667%
1999900 - 1999950          15      5.000%
1999950 <                   0      0.000%

Problem was found and tested against 2.6.18.  Patch is against 2.6.22.

Signed-off-by: Dave Johnson <djohnson@sw.starentnetworks.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-23 22:37:22 +02:00
Adrian Bunk
ea5806559f x86: add instrumentation menu
It seems commit 09cadedbdc was incomplete 
due to a clash with the x86 architecture merge.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-23 22:37:22 +02:00