Commit Graph

824 Commits

Author SHA1 Message Date
Randy Dunlap
d28bee0c0a [PATCH] Doc/kernel-doc: add more usage info
- Add info that structs, unions, enums, and typedefs are supported.

- Add doc about "private:" and "public:" tags for struct fields.

- Fix some typos.

- Remove some trailing whitespace.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:27 -08:00
Paul E. McKenney
d19720a909 [PATCH] RCU documentation fixes (January 2006 update)
Updates to in-tree RCU documentation based on comments over the past few
months.

Signed-off-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:25 -08:00
Christoph Lameter
a48d07afdf [PATCH] Direct Migration V9: migrate_pages() extension
Add direct migration support with fall back to swap.

Direct migration support on top of the swap based page migration facility.

This allows the direct migration of anonymous pages and the migration of file
backed pages by dropping the associated buffers (requires writeout).

Fall back to swap out if necessary.

The patch is based on lots of patches from the hotplug project but the code
was restructured, documented and simplified as much as possible.

Note that an additional patch that defines the migrate_page() method for
filesystems is necessary in order to avoid writeback for anonymous and file
backed pages.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Mike Kravetz <kravetz@us.ibm.com>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:16 -08:00
Christoph Lameter
2a16e3f4b0 [PATCH] Reclaim slab during zone reclaim
If large amounts of zone memory are used by empty slabs then zone_reclaim
becomes uneffective.  This patch shakes the slab a bit.

The problem with this patch is that the slab reclaim is not containable to a
zone.  Thus slab reclaim may affect the whole system and be extremely slow.
This also means that we cannot determine how many pages were freed in this
zone.  Thus we need to go off node for at least one allocation.

The functionality is disabled by default.

We could modify the shrinkers to take a zone parameter but that would be quite
invasive.  Better ideas are welcome.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:16 -08:00
Christoph Lameter
1b2ffb7896 [PATCH] Zone reclaim: Allow modification of zone reclaim behavior
In some situations one may want zone_reclaim to behave differently.  For
example a process writing large amounts of memory will spew unto other nodes
to cache the writes if many pages in a zone become dirty.  This may impact the
performance of processes running on other nodes.

Allowing writes during reclaim puts a stop to that behavior and throttles the
process by restricting the pages to the local zone.

Similarly one may want to contain processes to local memory by enabling
regular swap behavior during zone_reclaim.  Off node memory allocation can
then be controlled through memory policies and cpusets.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:16 -08:00
Christoph Lameter
2a11ff06d7 [PATCH] zone_reclaim: configurable off node allocation period.
Currently the zone_reclaim code has a fixed window of 30 seconds of off node
allocations should a local zone have no unused pagecache pages left.  Reclaim
will be attempted again after this timeout period to avoid repeated useless
scans for memory.  This is also useful to established sufficiently large off
node allocation chunks to relieve the local node.

It may be beneficial to adjust that time period for some special situations.
For example if memory use was exceeding node capacity one may want to give up
for longer periods of time.  If memory spikes intermittendly then one may want
to shorten the time period to reduce the number of off node allocations.

This patch allows just that....

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:16 -08:00
David Gibson
c125a1838a [PATCH] powerpc: Add flattened device tree documentation
The flattened device tree is the only supported way of booting ARCH=powerpc
kernels on non Open Firmware machines.  The documentation for the flattened
tree format and contents has been discussed on mailing lists and lately has
been living in the dtc git tree.  Really, it ought to go in the kernel's
Documentation directory for maximum visibility.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:14 -08:00
Rafael J. Wysocki
853609b61e [PATCH] swsusp: use bytes as image size units
Make swsusp use bytes as the image size units, which is needed for future
compatibility.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:12 -08:00
Linus Torvalds
ef59c4e935 Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6 2006-01-31 18:13:32 -08:00
Richard Knutsson
051d989773 [PATCH] pci: Schedule removal of pci_module_init
Scheduled the removal of pci_module_init.

Signed-off-by: Richard Knutsson <ricknu-0@student.ltu.se>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-31 18:00:10 -08:00
Adrian Bunk
b4b2c0411e [PATCH] PCI: schedule PCI_LEGACY_PROC for removal
PCI_LEGACY_PROC is deprecated since 2.5.53 in favor of lspci(8).

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-31 18:00:10 -08:00
Adrian Bunk
7f2c01ab8a [PATCH] USB: drivers/usb/media/w9968cf.c: remove hooks for the vpp module
- the w9968cf-vpp module is not intended for inclusion into the kernel
- the upstream w9968cf package shipping the w9968cf-vpp module suggests
  to simply replace the w9968cf module shipped with the kernel

Therefore, there seems to be no good reason spending some bytes of
kernel memory for hooks for the w9968cf-vpp module.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Luca Risolia <luca.risolia@studio.unibo.it>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-31 17:23:42 -08:00
Luca Risolia
7ce08c93e3 [PATCH] USB: Add ET61X[12]51 Video4Linux2 driver
This patch adds a Video4Linux2 driver giving support
to ET61X151 and ET61X251 PC Camera Controllers made by
Etoms Electronics.

Signed-off-by: Luca Risolia <luca.risolia@studio.unibo.it>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-31 17:23:39 -08:00
Luca Risolia
cd6fcc555f [PATCH] USB: SN9C10x driver updates
SN9C10x driver updates:

- Use kzalloc() instead of kmalloc()
- Move some macro definitions from sn9c102.h to sn9c102_core.c
- Use vfree() and vmalloc_32() instead of rvfree() and rvmalloc()
- Fix mmap() sys call
- Documentation updates

Signed-off-by: Luca Risolia <luca.risolia@studio.unibo.it>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-31 17:23:38 -08:00
Luca Risolia
a966f3e751 [PATCH] USB: SN9C10x driver updates and bugfixes
SN9C10x driver updates and bugfixes.

Changes: + new, - removed, * cleanup, @ bugfix:

@ fix poll()
@ Remove bad get_ctrl()'s
* Reduce ioctl stack usage
* Remove final ";" from some macro definitions
* Better support for SN9C103
+ Add sn9c102_write_regs()
+ Add 0x0c45/0x602d to the list of SN9C10x based devices
+ Add support for OV7630 image sensors
+ Provide support for the built-in microphone interface of the SN9C103
+ Documentation updates
+ Add 0x0c45/0x602e to the list of SN9C10x based devices

Signed-off-by: Luca Risolia <luca.risolia@studio.unibo.it>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-31 17:23:38 -08:00
Hannes Reinecke
d60256b1b3 [SCSI] aic7xxx: update documentation
This patch updates the documentation for aic7xxx and aic79xx with fixes
from the adaptec driver.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-01-31 14:39:49 -06:00
Sumant Patro
1341c93922 [SCSI] megaraid_sas: new template defined to represent each type of controllers
This patch defines a new template to represent each type of
controllers (identified by the processor used). The template has
members that is set with appropriate values during driver
initialisation. This change is done to support new controllers with
minimal change to existing code. In future, for a new controller
support, a template will be declared and its members initialised
appropriately.

Signed-off-by: Sumant Patro <Sumant.Patro@lsil.com>

Rejections fixed and
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-01-29 11:25:30 -06:00
Sumant Patro
cb59aa6a7c [SCSI] megaraid_sas: cleanup queue command path
This patch (originally submitted by Christoph Hellwig) removes code
duplication in megasas_build_cmd.  It also defines
MEGASAS_IOC_FIRMWARE32 to allow 64 bit compiled applications to work.

Signed-off-by: Sumant Patro <Sumant.Patro@lsil.com>

Rejections fixed and
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-01-29 11:18:16 -06:00
Alan Cox
da9bb1d27b [PATCH] EDAC: core EDAC support code
This is a subset of the bluesmoke project core code, stripped of the NMI work
which isn't ready to merge and some of the "interesting" proc functionality
that needs reworking or just has no place in kernel.  It requires no core
kernel changes except the added scrub functions already posted.

The goal is to merge further functionality only after the core code is
accepted and proven in the base kernel, and only at the point the upstream
extras are really ready to merge.

From: doug thompson <norsk5@xmission.com>

  This converts EDAC to sysfs and is the final chunk neccessary before EDAC
  has a stable user space API and can be considered for submission into the
  base kernel.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: doug thompson <norsk5@xmission.com>
Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-18 19:20:31 -08:00
Christoph Lameter
1743660b91 [PATCH] Zone reclaim: proc override
proc support for zone reclaim

This patch creates a proc entry /proc/sys/vm/zone_reclaim_mode that may be
used to override the automatic determination of the zone reclaim made on
bootup.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-18 19:20:17 -08:00
Linus Torvalds
fb60a9fee9 Merge branch 'for-linus' of git://brick.kernel.dk/data/git/linux-2.6-block 2006-01-16 23:43:11 -08:00
Linus Torvalds
d669af9d5a Merge master.kernel.org:/pub/scm/linux/kernel/git/mchehab/v4l-dvb 2006-01-16 23:20:01 -08:00
Miklos Szeredi
bacac382fb [PATCH] fuse: update documentation for sysfs
Add documentation for new attributes in sysfs.  Also describe the filesystem.

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-16 23:15:31 -08:00
Mauro Carvalho Chehab
f87d09be8c Merge branch 'master' of ssh://master.kernel.org/pub/scm/linux/kernel/git/mchehab/v4l-dvb 2006-01-16 08:39:30 -02:00
Tejun Heo
5a22579137 barrier.txt got lost while the new barrier patchset was climbing up
the ladder to the mainline.  Add it back.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <axboe@suse.de>
2006-01-16 09:45:58 +01:00
Linus Torvalds
3f02d072d4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial 2006-01-15 16:43:29 -08:00
Mauro Carvalho Chehab
f1dccedc81 Merge ssh://master.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 2006-01-15 20:59:29 -02:00
Ingo Molnar
a9df3d0f31 [PATCH] When CONFIG_CC_OPTIMIZE_FOR_SIZE, allow gcc4 to control inlining
If optimizing for size (CONFIG_CC_OPTIMIZE_FOR_SIZE), allow gcc4 compilers
to decide what to inline and what not - instead of the kernel forcing gcc
to inline all the time.  This requires several places that require to be
inlined to be marked as such, previous patches in this series do that.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:16 -08:00
Randy Dunlap
16ab3adf56 [PATCH] Update kernel-parameters.txt IOSCHED to spell out 'anticipatory'
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:14 -08:00
Randy Dunlap
a6b25b675d [PATCH] nlm kernel-parameters update
Add 2 lockd kernel parameters and spell 2 others correctly.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Cc: Olaf Kirch <okir@suse.de>
Cc: <buraphalinuxserver@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:14 -08:00
Robin Holt
7339ff8302 [PATCH] Add tmpfs options for memory placement policies
Anything that writes into a tmpfs filesystem is liable to disproportionately
decrease the available memory on a particular node.  Since there's no telling
what sort of application (e.g.  dd/cp/cat) might be dropping large files
there, this lets the admin choose the appropriate default behavior for their
site's situation.

Introduce a tmpfs mount option which allows specifying a memory policy and
a second option to specify the nodelist for that policy.  With the default
policy, tmpfs will behave as it does today.  This patch adds support for
preferred, bind, and interleave policies.

The default policy will cause pages to be added to tmpfs files on the node
which is doing the writing.  Some jobs expect a single process to create
and manage the tmpfs files.  This results in a node which has a
significantly reduced number of free pages.

With this patch, the administrator can specify the policy and nodes for
that policy where they would prefer allocations.

This patch was originally written by Brent Casavant and Hugh Dickins.  I
added support for the bind and preferred policies and the mpol_nodelist
mount option.

Signed-off-by: Brent Casavant <bcasavan@sgi.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Robin Holt <holt@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 18:27:07 -08:00
Alexey Dobriyan
3235798804 Fix "stuct", "strut", "struc" typos
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-01-15 02:12:54 +01:00
Randy Dunlap
fad6a94ee6 Documentation/hpet.txt typo
Fix a typo.  Requested by Petr Vandrovec.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-01-15 02:09:54 +01:00
Adrian Bunk
575c968718 spelling: s/appropiate/appropriate/
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-01-15 02:00:17 +01:00
Linus Torvalds
12dbf3fc4d Merge master.kernel.org:/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6 2006-01-14 12:16:07 -08:00
Linus Torvalds
61b7efddc5 Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/spi-2.6 2006-01-14 10:43:26 -08:00
Xose Vazquez Perez
e1b114ee90 [PATCH] docs: update some updated code docs
Based on comments from Randy Dunlap on my previous commit
5b0ed2c64d

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-14 10:39:53 -08:00
David Brownell
2e10c84b9c [PATCH] SPI: add spi_butterfly driver
This adds a bitbanging parport based adaptor cable for AVR Butterfly, giving
SPI links to its DataFlash chip and (eventually) firmware running in the card.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-13 16:29:56 -08:00
David Brownell
7111763d39 [PATCH] spi: misc fixes
This collects some small SPI patches that seem to be missing from the MM tree:

  - spi_butterfly kbuild hooks got dropped somehow; this restores them
  - quick fix for a (theoretical?) m25p80_write() oops noted by Andrew
  - quick fix for a potential config-specific oops for mtd_dataflash()
  - minor doc tweaks

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-13 16:29:56 -08:00
David Brownell
0c868461fc [PATCH] SPI core tweaks, bugfix
This includes various updates to the SPI core:

  - Fixes a driver model refcount bug in spi_unregister_master() paths.

  - The spi_master structures now have wrappers which help keep drivers
    from needing class-level get/put for device data or for refcounts.

  - Check for a few setup errors that would cause oopsing later.

  - Docs say more about memory management.  Highlights the use of DMA-safe
    i/o buffers, and zero-initializing spi_message and such metadata.

  - Provide a simple alloc/free for spi_message and its spi_transfer;
    this is only one of the possible memory management policies.

Nothing to break code that already works.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-13 16:29:55 -08:00
David Brownell
b885244eb2 [PATCH] spi: add spi_driver to SPI framework
This is a refresh of the "Simple SPI Framework" found in 2.6.15-rc3-mm1
which makes the following changes:

  * There's now a "struct spi_driver".  This increase the footprint
    of the core a bit, since it now includes code to do what the driver
    core was previously handling directly.  Documentation and comments
    were updated to match.

  * spi_alloc_master() now does class_device_initialize(), so it can
    at least be refcounted before spi_register_master().  To match,
    spi_register_master() switched over to class_device_add().

  * States explicitly that after transfer errors, spi_devices will be
    deselected.  We want fault recovery procedures to work the same
    for all controller drivers.

  * Minor tweaks:  controller_data no longer points to readonly data;
    prevent some potential cast-from-null bugs with container_of calls;
    clarifies some existing kerneldoc,

And a few small cleanups.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-13 16:29:54 -08:00
David Brownell
8ae12a0d85 [PATCH] spi: simple SPI framework
This is the core of a small SPI framework, implementing the model of a
queue of messages which complete asynchronously (with thin synchronous
wrappers on top).

  - It's still less than 2KB of ".text" (ARM).  If there's got to be a
    mid-layer for something so simple, that's the right size budget.  :)

  - The guts use board-specific SPI device tables to build the driver
    model tree.  (Hardware probing is rarely an option.)

  - This version of Kconfig includes no drivers.  At this writing there
    are two known master controller drivers (PXA/SSP, OMAP MicroWire)
    and three protocol drivers (CS8415a, ADS7846, DataFlash) with LKML
    mentions of other drivers in development.

  - No userspace API.  There are several implementations to compare.
    Implement them like any other driver, and bind them with sysfs.

The changes from last version posted to LKML (on 11-Nov-2005) are minor,
and include:

  - One bugfix (removes a FIXME), with the visible effect of making device
    names be "spiB.C" where B is the bus number and C is the chipselect.

  - The "caller provides DMA mappings" mechanism now has kerneldoc, for
    DMA drivers that want to be fancy.

  - Hey, the framework init can be subsys_init.  Even though board init
    logic fires earlier, at arch_init ... since the framework init is
    for driver support, and the board init support uses static init.

  - Various additional spec/doc clarifications based on discussions
    with other folk.  It adds a brief "thank you" at the end, for folk
    who've helped nudge this framework into existence.

As I've said before, I think that "protocol tweaking" is the main support
that this driver framework will need to evolve.

From: Mark Underwood <basicmark@yahoo.com>

  Update the SPI framework to remove a potential priority inversion case by
  reverting to kmalloc if the pre-allocated DMA-safe buffer isn't available.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-13 16:29:54 -08:00
Hans Verkuil
b3d37042d7 V4L/DVB (3363): Add support for Samsung tuner TCPN 2121P30A
- Add support for Samsung tuner TCPN 2121P30A, used in
  Hauppauge PVR-500 cards.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2006-01-13 14:10:25 -02:00
Mark Haverkamp
6171b5eff2 [SCSI] aacraid: README update
Received From Mark Salyzyn.

Move the README from the driver directory to the Documentation directory.
Updated the documentation, added descriptions for cards that
were missing.

Signed-off-by: Mark Haverkamp <markh@osdl.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-01-12 11:55:16 -06:00
akpm@osdl.org
198e2f1811 [PATCH] scheduler cache-hot-autodetect
)

From: Ingo Molnar <mingo@elte.hu>

This is the latest version of the scheduler cache-hot-auto-tune patch.

The first problem was that detection time scaled with O(N^2), which is
unacceptable on larger SMP and NUMA systems. To solve this:

- I've added a 'domain distance' function, which is used to cache
  measurement results. Each distance is only measured once. This means
  that e.g. on NUMA distances of 0, 1 and 2 might be measured, on HT
  distances 0 and 1, and on SMP distance 0 is measured. The code walks
  the domain tree to determine the distance, so it automatically follows
  whatever hierarchy an architecture sets up. This cuts down on the boot
  time significantly and removes the O(N^2) limit. The only assumption
  is that migration costs can be expressed as a function of domain
  distance - this covers the overwhelming majority of existing systems,
  and is a good guess even for more assymetric systems.

  [ People hacking systems that have assymetries that break this
    assumption (e.g. different CPU speeds) should experiment a bit with
    the cpu_distance() function. Adding a ->migration_distance factor to
    the domain structure would be one possible solution - but lets first
    see the problem systems, if they exist at all. Lets not overdesign. ]

Another problem was that only a single cache-size was used for measuring
the cost of migration, and most architectures didnt set that variable
up. Furthermore, a single cache-size does not fit NUMA hierarchies with
L3 caches and does not fit HT setups, where different CPUs will often
have different 'effective cache sizes'. To solve this problem:

- Instead of relying on a single cache-size provided by the platform and
  sticking to it, the code now auto-detects the 'effective migration
  cost' between two measured CPUs, via iterating through a wide range of
  cachesizes. The code searches for the maximum migration cost, which
  occurs when the working set of the test-workload falls just below the
  'effective cache size'. I.e. real-life optimized search is done for
  the maximum migration cost, between two real CPUs.

  This, amongst other things, has the positive effect hat if e.g. two
  CPUs share a L2/L3 cache, a different (and accurate) migration cost
  will be found than between two CPUs on the same system that dont share
  any caches.

(The reliable measurement of migration costs is tricky - see the source
for details.)

Furthermore i've added various boot-time options to override/tune
migration behavior.

Firstly, there's a blanket override for autodetection:

	migration_cost=1000,2000,3000

will override the depth 0/1/2 values with 1msec/2msec/3msec values.

Secondly, there's a global factor that can be used to increase (or
decrease) the autodetected values:

	migration_factor=120

will increase the autodetected values by 20%. This option is useful to
tune things in a workload-dependent way - e.g. if a workload is
cache-insensitive then CPU utilization can be maximized by specifying
migration_factor=0.

I've tested the autodetection code quite extensively on x86, on 3
P3/Xeon/2MB, and the autodetected values look pretty good:

Dual Celeron (128K L2 cache):

 ---------------------
 migration cost matrix (max_cache_size: 131072, cpu: 467 MHz):
 ---------------------
           [00]    [01]
 [00]:     -     1.7(1)
 [01]:   1.7(1)    -
 ---------------------
 cacheflush times [2]: 0.0 (0) 1.7 (1784008)
 ---------------------

Here the slow memory subsystem dominates system performance, and even
though caches are small, the migration cost is 1.7 msecs.

Dual HT P4 (512K L2 cache):

 ---------------------
 migration cost matrix (max_cache_size: 524288, cpu: 2379 MHz):
 ---------------------
           [00]    [01]    [02]    [03]
 [00]:     -     0.4(1)  0.0(0)  0.4(1)
 [01]:   0.4(1)    -     0.4(1)  0.0(0)
 [02]:   0.0(0)  0.4(1)    -     0.4(1)
 [03]:   0.4(1)  0.0(0)  0.4(1)    -
 ---------------------
 cacheflush times [2]: 0.0 (33900) 0.4 (448514)
 ---------------------

Here it can be seen that there is no migration cost between two HT
siblings (CPU#0/2 and CPU#1/3 are separate physical CPUs). A fast memory
system makes inter-physical-CPU migration pretty cheap: 0.4 msecs.

8-way P3/Xeon [2MB L2 cache]:

 ---------------------
 migration cost matrix (max_cache_size: 2097152, cpu: 700 MHz):
 ---------------------
           [00]    [01]    [02]    [03]    [04]    [05]    [06]    [07]
 [00]:     -    19.2(1) 19.2(1) 19.2(1) 19.2(1) 19.2(1) 19.2(1) 19.2(1)
 [01]:  19.2(1)    -    19.2(1) 19.2(1) 19.2(1) 19.2(1) 19.2(1) 19.2(1)
 [02]:  19.2(1) 19.2(1)    -    19.2(1) 19.2(1) 19.2(1) 19.2(1) 19.2(1)
 [03]:  19.2(1) 19.2(1) 19.2(1)    -    19.2(1) 19.2(1) 19.2(1) 19.2(1)
 [04]:  19.2(1) 19.2(1) 19.2(1) 19.2(1)    -    19.2(1) 19.2(1) 19.2(1)
 [05]:  19.2(1) 19.2(1) 19.2(1) 19.2(1) 19.2(1)    -    19.2(1) 19.2(1)
 [06]:  19.2(1) 19.2(1) 19.2(1) 19.2(1) 19.2(1) 19.2(1)    -    19.2(1)
 [07]:  19.2(1) 19.2(1) 19.2(1) 19.2(1) 19.2(1) 19.2(1) 19.2(1)    -
 ---------------------
 cacheflush times [2]: 0.0 (0) 19.2 (19281756)
 ---------------------

This one has huge caches and a relatively slow memory subsystem - so the
migration cost is 19 msecs.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Cc: <wilder@us.ibm.com>
Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-12 09:08:50 -08:00
Linus Torvalds
593195f9b2 Merge master.kernel.org:/pub/scm/linux/kernel/git/mchehab/v4l-dvb 2006-01-11 19:36:32 -08:00
Andi Kleen
7eb903f4a5 [PATCH] x86_64: Add documentation for CPU hotplug ACPI extension
Cc: len.brown@intel.com, ashok.ray@intel.com

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-11 19:01:11 -08:00
Andi Kleen
f62a91f691 [PATCH] x86_64: Don't reserve hotplug CPUs by default
Most users don't need it so no need to waste memory.
This means an user has to specify the appropiate number of
hotplug CPUs on the command line with additional_cpus=...
or fix their BIOS to follow the convention in
Documentation/x86-64/cpu-hotplug-spec

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-11 19:01:11 -08:00
Tore Anderson
e56d5ae305 [PATCH] ext3: fix documentation of online resizing
Undocument the non-working resize= mount option in ext3, and add some
references to the ext2resize package instead, which appears to be the only
proper way of doing online resizing of ext3 filesystems.

Signed-off-by: Tore Anderson <tore@fud.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-11 18:42:10 -08:00
Akinobu Mita
75ba0861bc [PATCH] doc: refer to kdump in oops-tracing.txt
Kdump has been merged and supported on several architectures.  It is better
to encourage to use kdump rather than non standard kernel crash dump
patches.

Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-11 18:42:10 -08:00