Commit Graph

45 Commits

Author SHA1 Message Date
Thomas Gleixner
764e0da14f timers: Fixup the Kconfig consolidation fallout
Sigh, I missed to check which architecture Kconfig files actually
include the core Kconfig file. There are a few which did not. So we
broke them.

Instead of adding the includes to those, we are better off to move the
include to init/Kconfig like we did already with irqs and others.

This does not change anything for the architectures using the old
style periodic timer mode. It just solves the build wreckage there.

For those architectures which use the clock events infrastructure it
moves the include of the core Kconfig file to "General setup" which is
a way more logical place than having it at random locations specified
by the architecture specific Kconfigs.

Reported-by: Ingo Molnar <mingo@kernel.org>
Cc: Anna-Maria Gleixner <anna-maria@glx-um.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-05-21 23:43:46 +02:00
Anna-Maria Gleixner
ea5332098e mn10300: Use generic time config
Signed-off-by: Anna-Maria Gleixner <anna-maria@glx-um.de>
Cc: David Howells <dhowells@redhat.com>
Link: http://lkml.kernel.org/r/20120518163106.201635926@glx-um.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-05-21 11:01:43 +02:00
Cong Wang
d314d74c69 nmi watchdog: do not use cpp symbol in Kconfig
ARCH_HAS_NMI_WATCHDOG is a macro defined by arch, but config
HARDLOCKUP_DETECTOR depends on it.  This is wrong, ARCH_HAS_NMI_WATCHDOG
has to be a Kconfig config, and arch's need it should select it
explicitly.

Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Cc: David Howells <dhowells@redhat.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:31 -07:00
Michael S. Tsirkin
34f1bdee19 mn10300: switch to GENERIC_PCI_IOMAP
The pci_iomap variant that arch/mn10300/unit-asb2305/pci-iomap.c
uses differs from the generic one in that it does
not use ioremap_nocache for PCI addresses.
However, it turns out that PCI addresses are
automatically noncached, so switching to ioremap_nocache
and to the generic implementation is safe.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-12-04 16:00:17 +02:00
Linus Torvalds
39adff5f69 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  time, s390: Get rid of compile warning
  dw_apb_timer: constify clocksource name
  time: Cleanup old CONFIG_GENERIC_TIME references that snuck in
  time: Change jiffies_to_clock_t() argument type to unsigned long
  alarmtimers: Fix error handling
  clocksource: Make watchdog reset lockless
  posix-cpu-timers: Cure SMP accounting oddities
  s390: Use direct ktime path for s390 clockevent device
  clockevents: Add direct ktime programming function
  clockevents: Make minimum delay adjustments configurable
  nohz: Remove "Switched to NOHz mode" debugging messages
  proc: Consider NO_HZ when printing idle and iowait times
  nohz: Make idle/iowait counter update conditional
  nohz: Fix update_ts_time_stat idle accounting
  cputime: Clean up cputime_to_usecs and usecs_to_cputime macros
  alarmtimers: Rework RTC device selection using class interface
  alarmtimers: Add try_to_cancel functionality
  alarmtimers: Add more refined alarm state tracking
  alarmtimers: Remove period from alarm structure
  alarmtimers: Remove interval cap limit hack
  ...
2011-10-26 17:15:03 +02:00
John Stultz
dcb69290af time: Cleanup old CONFIG_GENERIC_TIME references that snuck in
Awhile back I removed all the CONFIG_GENERIC_TIME referecnes as
the last of the non-GENERIC_TIME arches were converted.

However, due to the functionality being important and around for
awhile, there apparently were some out of tree hardware enablement
patches that used it and have since been merged.

This patch removes the remaining instances of GENERIC_TIME.

Singed-off-by: John Stultz <john.stultz@linaro.org>
2011-10-04 13:07:47 -07:00
Paul Bolle
395cf9691d doc: fix broken references
There are numerous broken references to Documentation files (in other
Documentation files, in comments, etc.). These broken references are
caused by typo's in the references, and by renames or removals of the
Documentation files. Some broken references are simply odd.

Fix these broken references, sometimes by dropping the irrelevant text
they were part of.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-09-27 18:08:04 +02:00
Akinobu Mita
63e424c844 arch: remove CONFIG_GENERIC_FIND_{NEXT_BIT,BIT_LE,LAST_BIT}
By the previous style change, CONFIG_GENERIC_FIND_NEXT_BIT,
CONFIG_GENERIC_FIND_BIT_LE, and CONFIG_GENERIC_FIND_LAST_BIT are not used
to test for existence of find bitops anymore.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-26 17:12:38 -07:00
Thomas Gleixner
78c8982564 genirq: Remove the now obsolete config options and select statements
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-03-30 14:13:23 +02:00
Thomas Gleixner
2a8f55b1f5 mn10300: Use generic show_interrupts()
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-03-29 14:48:19 +02:00
David Howells
e460d64405 MN10300: Use KGDB 2011-03-18 16:54:31 +00:00
David Howells
67ddb4052d MN10300: Create generic kernel debugger hooks
Create generic kernel debugger hooks in the MN10300 arch and make gdbstub use
them.  This is a preparation for KGDB support.

Signed-off-by: David Howells <dhowells@redhat.com>
2011-03-18 16:54:30 +00:00
David Howells
792576b1c5 MN10300: Introduce a general config option for kernel debugger hooks
Introduce a general config option for kernel debugger hooks so that both
gdbstub and kgdb can use it and add a header file for both debuggers to use.

Signed-off-by: David Howells <dhowells@redhat.com>
2011-03-18 16:54:30 +00:00
Thomas Gleixner
df43b86b41 MN10300: Select GENERIC_HARDIRQS_NO_DEPRECATED
All chips converted.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Howells <dhowells@redhat.com>
2011-03-18 16:52:53 +00:00
David Howells
4692edbd4c MN10300: Select HAVE_GENERIC_HARDIRQS rather than GENERIC_HARDIRQS
Select HAVE_GENERIC_HARDIRQS rather than GENERIC_HARDIRQS in MN10300's main
Kconfig file to avoid this warning:

warning: (MN10300) selects GENERIC_HARDIRQS which has unmet direct dependencies (HAVE_GENERIC_HARDIRQS)

Signed-off-by: David Howells <dhowells@redhat.com>
2011-03-18 16:52:53 +00:00
Thomas Gleixner
73a173a411 MN10300: Remove stale code
mn10300 implements clocksource and clockevents and selects them
unconditionally in Kconfig. Remove the stale code which seems to be a
leftover of the conversion. Cleanup the configuration switches as well.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Mark Salter <msalter@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2011-03-18 16:52:49 +00:00
Thomas Gleixner
b169c908a5 mn10300: Use generic irq Kconfig
No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Howells <dhowells@redhat.com>
2011-01-21 11:55:33 +01:00
Thomas Gleixner
1c77ff22f5 genirq: Remove __do_IRQ
All architectures are finally converted. Remove the cruft.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Michal Simek <monstr@monstr.eu>
Acked-by: David Howells <dhowells@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jeff Dike <jdike@addtoit.com>
2011-01-21 11:55:31 +01:00
Amerigo Wang
351f8f8e64 kernel: clean up USE_GENERIC_SMP_HELPERS
For arch which needs USE_GENERIC_SMP_HELPERS, it has to select
USE_GENERIC_SMP_HELPERS, rather than leaving a choice to user, since they
don't provide their own implementions.

Also, move on_each_cpu() to kernel/smp.c, it is strange to put it in
kernel/softirq.c.

For arch which doesn't use USE_GENERIC_SMP_HELPERS, e.g.  blackfin, only
on_each_cpu() is compiled.

Signed-off-by: Amerigo Wang <amwang@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:08 -08:00
Linus Torvalds
51399a3919 Merge branch 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6
* 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6: (38 commits)
  kbuild: convert `arch/tile' to the kconfig mainmenu upgrade
  README: cite nconfig
  Revert "kconfig: Temporarily disable dependency warnings"
  kconfig: Use PATH_MAX instead of 128 for path buffer sizes.
  kconfig: Fix realloc usage()
  kconfig: Propagate const
  kconfig: Don't go out from read config loop when you read new symbol
  kconfig: fix menuconfig on debian lenny
  kbuild: migrate all arch to the kconfig mainmenu upgrade
  kconfig: expand file names
  kconfig: use the file's name of sourced file
  kconfig: constify file name
  kconfig: don't emit warning upon rootmenu's prompt redefinition
  kconfig: replace KERNELVERSION usage by the mainmenu's prompt
  kconfig: delay gconf window initialization
  kconfig: expand by default the rootmenu's prompt
  kconfig: add a symbol string expansion helper
  kconfig: regen parser
  kconfig: implement the `mainmenu' directive
  kconfig: allow PACKAGE to be defined on the compiler's command-line
  ...

Fix up trivial conflict in arch/mn10300/Kconfig
2010-10-28 16:16:39 -07:00
Akira Takeuchi
a5e03ca2fd MN10300: Change "Matsushita" to "Panasonic".
Change externally visible "Matsushita" instances to "Panasonic" throughout the
MN10300 arch code.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-27 17:29:00 +01:00
Akira Takeuchi
62747cd27e MN10300: ASB2364: Add support for SMSC911X and SMC911X
Add support for SMSC911X and SMC911X for the ASB2364 unit.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: steve.glendinning@smsc.com
cc: netdev@vger.kernel.org
2010-10-27 17:28:58 +01:00
Mark Salter
730c1fad0e MN10300: Generic time support
Implement generic time support for MN10300.

Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-27 17:28:57 +01:00
Akira Takeuchi
368dd5acd1 MN10300: And Panasonic AM34 subarch and implement SMP
Implement the Panasonic MN10300 AM34 CPU subarch and implement SMP support for
MN10300.  Also implement support for the MN2WS0060 processor and the ASB2364
evaluation board which are AM34 based.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-27 17:28:55 +01:00
Akira Takeuchi
37e4ec9636 MN10300: Make various interrupt priority settings configurable
Make the settings of interrupt priorities used by various services configurable
at run time.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-27 17:28:54 +01:00
Akira Takeuchi
278d91c460 MN10300: Make the FPU operate in non-lazy mode under SMP
Make the FPU operate in non-lazy mode under SMP so that when the process that
is currently using the FPU migrates to a different CPU, we don't have to ping
its previous CPU to flush the FPU context.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-27 17:28:52 +01:00
Akira Takeuchi
a9bc60ebfd MN10300: Make the use of PIDR to mark TLB entries controllable
Make controllable the use of the PIDR register to mark TLB entries as belonging
to particular processes.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-27 17:28:49 +01:00
Akira Takeuchi
8f19e3daf3 MN10300: AM34 erratum requires MMUCTR read and write on exception entry
An AM34 erratum requires MMUCTR read and write on entry to certain exceptions,
prior to EPSW.NMID being cleared to allow NMIs to happen.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-27 17:28:48 +01:00
David Howells
b478491f26 MN10300: Allow some cacheflushes to be avoided if cache snooping is available
The AM34 core is able to do cache snooping, and so can skip some of the cache
flushing.

Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-27 17:28:46 +01:00
David Howells
0bc42d7fcb MN10300: Cache: Split cache bits out of arch Kconfig
Split the cache bits out of arch/mn10300/Kconfig as they're quite complex.

Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-27 17:28:41 +01:00
Akira Takeuchi
8fbbf7c76a MN10300: Add CPU register bits for AM34
Add CPU register declarations for the AM34 subarch.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-27 17:28:40 +01:00
Akira Takeuchi
22d4225f61 MN10300: Differentiate AM33_2 and AM33_3 in config
Differentiate AM33_2 and AM33_3 CPU cores in configuration.  The MN103E010
processor contains an AM33_2 core.

Whilst we're at it, prepare for AM34-based stuff by declaring AM34_2 too.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-27 17:28:38 +01:00
Michal Marek
239060b93b Merge branch 'kbuild/rc-fixes' into kbuild/kconfig
We need to revert the temporary hack in 71ebc01, hence the merge.
2010-10-12 15:09:06 +02:00
Mark Salter
ed3473b18f MN10300: Arch doesn't support HAVE_ARCH_TRACEHOOK
Remove specification of HAVE_ARCH_TRACEHOOK for MN10300 as the arch does not
support it at this time.

Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-23 10:20:58 -07:00
Arnaud Lacombe
838a2e55e6 kbuild: migrate all arch to the kconfig mainmenu upgrade
Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Michal Marek <mmarek@suse.cz>
2010-09-19 22:54:11 -04:00
John Stultz
592913ecb8 time: Kill off CONFIG_GENERIC_TIME
Now that all arches have been converted over to use generic time via
clocksources or arch_gettimeoffset(), we can remove the GENERIC_TIME
config option and simplify the generic code.

Signed-off-by: John Stultz <johnstul@us.ibm.com>
LKML-Reference: <1279068988-21864-4-git-send-email-johnstul@us.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-07-27 12:40:54 +02:00
John Stultz
f7a56575fa mn10300: Convert mn10300 to use read/update_persistent_clock
This patch converts the mn10300 architecture to use the generic
read_persistent_clock and update_persistent_clock interfaces, reducing
the amount of arch specific code we have to maintain, and allowing for
further cleanups in the future.

I have not built or tested this patch, so help from arch maintainers
would be appreciated.

Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <1267675049-12337-3-git-send-email-johnstul@us.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-03-13 01:14:09 +01:00
David Howells
5d289964e1 MN10300: Add utrace/tracehooks support
Add utrace/tracehooks support to MN10300.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11 09:02:20 -07:00
David Howells
62b8e680e6 MN10300: Kill MN10300's own profiling Kconfig
Kill MN10300's own profiling Kconfig as this is superfluous given that the
profiling options have moved to init/Kconfig and arch/Kconfig.  Not only is
this now superfluous, but the dependencies are not correct.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-09 10:53:16 -07:00
David Howells
58bafe72ad mn10300: fix oprofile
oprofile for MN10300 seems to have been broken by the advent of the new
tracing framework.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-20 17:57:48 -08:00
Matt Helsley
dc52ddc0e6 container freezer: implement freezer cgroup subsystem
This patch implements a new freezer subsystem in the control groups
framework.  It provides a way to stop and resume execution of all tasks in
a cgroup by writing in the cgroup filesystem.

The freezer subsystem in the container filesystem defines a file named
freezer.state.  Writing "FROZEN" to the state file will freeze all tasks
in the cgroup.  Subsequently writing "RUNNING" will unfreeze the tasks in
the cgroup.  Reading will return the current state.

* Examples of usage :

   # mkdir /containers/freezer
   # mount -t cgroup -ofreezer freezer  /containers
   # mkdir /containers/0
   # echo $some_pid > /containers/0/tasks

to get status of the freezer subsystem :

   # cat /containers/0/freezer.state
   RUNNING

to freeze all tasks in the container :

   # echo FROZEN > /containers/0/freezer.state
   # cat /containers/0/freezer.state
   FREEZING
   # cat /containers/0/freezer.state
   FROZEN

to unfreeze all tasks in the container :

   # echo RUNNING > /containers/0/freezer.state
   # cat /containers/0/freezer.state
   RUNNING

This is the basic mechanism which should do the right thing for user space
task in a simple scenario.

It's important to note that freezing can be incomplete.  In that case we
return EBUSY.  This means that some tasks in the cgroup are busy doing
something that prevents us from completely freezing the cgroup at this
time.  After EBUSY, the cgroup will remain partially frozen -- reflected
by freezer.state reporting "FREEZING" when read.  The state will remain
"FREEZING" until one of these things happens:

	1) Userspace cancels the freezing operation by writing "RUNNING" to
		the freezer.state file
	2) Userspace retries the freezing operation by writing "FROZEN" to
		the freezer.state file (writing "FREEZING" is not legal
		and returns EIO)
	3) The tasks that blocked the cgroup from entering the "FROZEN"
		state disappear from the cgroup's set of tasks.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: export thaw_process]
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Signed-off-by: Matt Helsley <matthltc@us.ibm.com>
Acked-by: Serge E. Hallyn <serue@us.ibm.com>
Tested-by: Matt Helsley <matthltc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:52:34 -07:00
David Woodhouse
6b213e1bc2 Remove redundant CONFIG_ARCH_SUPPORTS_AOUT
We don't need this any more; arguably we never really did.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2008-09-06 19:30:20 +01:00
Linus Torvalds
8e3e076c5a BKL: revert back to the old spinlock implementation
The generic semaphore rewrite had a huge performance regression on AIM7
(and potentially other BKL-heavy benchmarks) because the generic
semaphores had been rewritten to be simple to understand and fair.  The
latter, in particular, turns a semaphore-based BKL implementation into a
mess of scheduling.

The attempt to fix the performance regression failed miserably (see the
previous commit 00b41ec261 'Revert
"semaphore: fix"'), and so for now the simple and sane approach is to
instead just go back to the old spinlock-based BKL implementation that
never had any issues like this.

This patch also has the advantage of being reported to fix the
regression completely according to Yanmin Zhang, unlike the semaphore
hack which still left a couple percentage point regression.

As a spinlock, the BKL obviously has the potential to be a latency
issue, but it's not really any different from any other spinlock in that
respect.  We do want to get rid of the BKL asap, but that has been the
plan for several years.

These days, the biggest users are in the tty layer (open/release in
particular) and Alan holds out some hope:

  "tty release is probably a few months away from getting cured - I'm
   afraid it will almost certainly be the very last user of the BKL in
   tty to get fixed as it depends on everything else being sanely locked."

so while we're not there yet, we do have a plan of action.

Tested-by: Yanmin Zhang <yanmin_zhang@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Alexander Viro <viro@ftp.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-10 20:58:02 -07:00
David Howells
860f7be283 MN10300: define HZ as a config option
Define HZ as a config option.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-23 17:12:13 -08:00
David Howells
b920de1b77 mn10300: add the MN10300/AM33 architecture to the kernel
Add architecture support for the MN10300/AM33 CPUs produced by MEI to the
kernel.

This patch also adds board support for the ASB2303 with the ASB2308 daughter
board, and the ASB2305.  The only processor supported is the MN103E010, which
is an AM33v2 core plus on-chip devices.

[akpm@linux-foundation.org: nuke cvs control strings]
Signed-off-by: Masakazu Urade <urade.masakazu@jp.panasonic.com>
Signed-off-by: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:30 -08:00