Commit Graph

4395 Commits

Author SHA1 Message Date
Uwe Kleine-König
82736f4d1d generic irqs: handle failure of irqchip->set_type in setup_irq
set_type returns an int indicating success or failure, but up to now
setup_irq ignores that.

In my case this resulted in a machine hang:

gpio-keys requested IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING, but
arm/ns9xxx can only trigger on one direction so set_type didn't touch
the configuration which happens do default to a level sensitiveness and
returned -EINVAL.  setup_irq ignored that and unmasked the irq.  This
resulted in an endless triggering of the gpio-key interrupt service
routine which effectively killed the machine.

With this patch applied setup_irq propagates the error to the caller.

Note that before in the case

	chip && !chip->set_type && !chip->name

a NULL pointer was feed to printk.  This is fixed, too.

Signed-off-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:24 -07:00
David Howells
f0af566da6 pm: fix try_to_freeze_tasks()'s use of do_div()
Fix try_to_freeze_tasks()'s use of do_div() on an s64 by making
elapsed_csecs64 a u64 instead and dividing that.

Possibly this should be guarded lest the interval calculation turn up
negative, but the possible negativity of the result of the division is
cast away anyway.

This was introduced by patch 438e2ce68d.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:24 -07:00
Zhang Rui
2f15fc4bdf pm: schedule sysrq poweroff on boot cpu
schedule sysrq poweroff on boot cpu.

sysrq poweroff needs to disable nonboot cpus, and we need to run this on boot
cpu to avoid any recursion.  http://bugzilla.kernel.org/show_bug.cgi?id=10897

[kosaki.motohiro@jp.fujitsu.com: build fix]
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Rus <harbour@sfinx.od.ua>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:24 -07:00
Zhang Rui
c1a220e7ac pm: introduce new interfaces schedule_work_on() and queue_work_on()
This interface allows adding a job on a specific cpu.

Although a work struct on a cpu will be scheduled to other cpu if the cpu
dies, there is a recursion if a work task tries to offline the cpu it's
running on.  we need to schedule the task to a specific cpu in this case.
http://bugzilla.kernel.org/show_bug.cgi?id=10897

[oleg@tv-sign.ru: cleanups]
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Rus <harbour@sfinx.od.ua>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:23 -07:00
Akinobu Mita
0d83304c7e pm: hibernation: simplify memory bitmap
This patch simplifies the memory bitmap manipulations.

- remove the member size in struct bm_block

It is not necessary for struct bm_block to have the number of bit chunks that
can be calculated by using end_pfn and start_pfn.

- use find_next_bit() for memory_bm_next_pfn

No need to invent the bitmap library only for the memory bitmap.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:23 -07:00
David Brownell
77437fd4e6 pm: boot time suspend selftest
Boot-time test for system suspend states (STR or standby).  The generic
RTC framework triggers wakeup alarms, which are used to exit those states.

  - Measures some aspects of suspend time ... this uses "jiffies" until
    someone converts it to use a timebase that works properly even while
    timer IRQs are disabled.

  - Triggered by a command line parameter.  By default nothing even
    vaguely troublesome will happen, but "test_suspend=mem" will give
    you a brief STR test during system boot.  (Or you may need to use
    "test_suspend=standby" instead, if your hardware needs that.)

This isn't without problems.  It fires early enough during boot that for
example both PCMCIA and MMC stacks have misbehaved.  The workaround in
those cases was to boot without such media cards inserted.

[matthltc@us.ibm.com: fix compile failure in boot time suspend selftest]
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Pavel Machek <pavel@suse.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-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>
2008-07-24 10:47:22 -07:00
Pavel Machek
0d63081d41 swsusp: provide users with a hint about the no_console_suspend option
Tell the user about the no_console_suspend option, so that we don't have to
tell each bug reporter personally.

[akpm@linux-foundation.org: clarify the text a little]
Signed-off-by: Pavel Machek <pavel@suse.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:22 -07:00
Andrew G. Morgan
ab763c7112 security: filesystem capabilities refactor kernel code
To date, we've tried hard to confine filesystem support for capabilities
to the security modules.  This has left a lot of the code in
kernel/capability.c in a state where it looks like it supports something
that filesystem support for capabilities actually suppresses when the LSM
security/commmoncap.c code runs.  What is left is a lot of code that uses
sub-optimal locking in the main kernel

With this change we refactor the main kernel code and make it explicit
which locks are needed and that the only remaining kernel races in this
area are associated with non-filesystem capability code.

Signed-off-by: Andrew G. Morgan <morgan@kernel.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:22 -07:00
Andi Kleen
e5ff215941 hugetlb: multiple hstates for multiple page sizes
Add basic support for more than one hstate in hugetlbfs.  This is the key
to supporting multiple hugetlbfs page sizes at once.

- Rather than a single hstate, we now have an array, with an iterator
- default_hstate continues to be the struct hstate which we use by default
- Add functions for architectures to register new hstates

[akpm@linux-foundation.org: coding-style fixes]
Acked-by: Adam Litke <agl@us.ibm.com>
Acked-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:17 -07:00
Mel Gorman
a1e78772d7 hugetlb: reserve huge pages for reliable MAP_PRIVATE hugetlbfs mappings until fork()
This patch reserves huge pages at mmap() time for MAP_PRIVATE mappings in
a similar manner to the reservations taken for MAP_SHARED mappings.  The
reserve count is accounted both globally and on a per-VMA basis for
private mappings.  This guarantees that a process that successfully calls
mmap() will successfully fault all pages in the future unless fork() is
called.

The characteristics of private mappings of hugetlbfs files behaviour after
this patch are;

1. The process calling mmap() is guaranteed to succeed all future faults until
   it forks().
2. On fork(), the parent may die due to SIGKILL on writes to the private
   mapping if enough pages are not available for the COW. For reasonably
   reliable behaviour in the face of a small huge page pool, children of
   hugepage-aware processes should not reference the mappings; such as
   might occur when fork()ing to exec().
3. On fork(), the child VMAs inherit no reserves. Reads on pages already
   faulted by the parent will succeed. Successful writes will depend on enough
   huge pages being free in the pool.
4. Quotas of the hugetlbfs mount are checked at reserve time for the mapper
   and at fault time otherwise.

Before this patch, all reads or writes in the child potentially needs page
allocations that can later lead to the death of the parent.  This applies
to reads and writes of uninstantiated pages as well as COW.  After the
patch it is only a write to an instantiated page that causes problems.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Adam Litke <agl@us.ibm.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:16 -07:00
Adrian Bunk
c748e1340e mm/vmstat.c: proper externs
This patch adds proper extern declarations for five variables in
include/linux/vmstat.h

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:14 -07:00
Linus Torvalds
338b9bb3ad Merge branch 'x86/auditsc' of git://git.kernel.org/pub/scm/linux/kernel/git/frob/linux-2.6-roland
* 'x86/auditsc' of git://git.kernel.org/pub/scm/linux/kernel/git/frob/linux-2.6-roland:
  i386 syscall audit fast-path
  x86_64 ia32 syscall audit fast-path
  x86_64 syscall audit fast-path
  x86_64: remove bogus optimization in sysret_signal
2008-07-23 20:39:21 -07:00
Linus Torvalds
7f9dce3837 Merge branch 'sched/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sched: hrtick_enabled() should use cpu_active()
  sched, x86: clean up hrtick implementation
  sched: fix build error, provide partition_sched_domains() unconditionally
  sched: fix warning in inc_rt_tasks() to not declare variable 'rq' if it's not needed
  cpu hotplug: Make cpu_active_map synchronization dependency clear
  cpu hotplug, sched: Introduce cpu_active_map and redo sched domain managment (take 2)
  sched: rework of "prioritize non-migratable tasks over migratable ones"
  sched: reduce stack size in isolated_cpu_setup()
  Revert parts of "ftrace: do not trace scheduler functions"

Fixed up conflicts in include/asm-x86/thread_info.h (due to the
TIF_SINGLESTEP unification vs TIF_HRTICK_RESCHED removal) and
kernel/sched_fair.c (due to cpu_active_map vs for_each_cpu_mask_nr()
introduction).
2008-07-23 19:36:53 -07:00
Linus Torvalds
26dcce0fab Merge branch 'cpus4096-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'cpus4096-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (31 commits)
  NR_CPUS: Replace NR_CPUS in speedstep-centrino.c
  cpumask: Provide a generic set of CPUMASK_ALLOC macros, FIXUP
  NR_CPUS: Replace NR_CPUS in cpufreq userspace routines
  NR_CPUS: Replace per_cpu(..., smp_processor_id()) with __get_cpu_var
  NR_CPUS: Replace NR_CPUS in arch/x86/kernel/genapic_flat_64.c
  NR_CPUS: Replace NR_CPUS in arch/x86/kernel/genx2apic_uv_x.c
  NR_CPUS: Replace NR_CPUS in arch/x86/kernel/cpu/proc.c
  NR_CPUS: Replace NR_CPUS in arch/x86/kernel/cpu/mcheck/mce_64.c
  cpumask: Optimize cpumask_of_cpu in lib/smp_processor_id.c, fix
  cpumask: Use optimized CPUMASK_ALLOC macros in the centrino_target
  cpumask: Provide a generic set of CPUMASK_ALLOC macros
  cpumask: Optimize cpumask_of_cpu in lib/smp_processor_id.c
  cpumask: Optimize cpumask_of_cpu in kernel/time/tick-common.c
  cpumask: Optimize cpumask_of_cpu in drivers/misc/sgi-xp/xpc_main.c
  cpumask: Optimize cpumask_of_cpu in arch/x86/kernel/ldt.c
  cpumask: Optimize cpumask_of_cpu in arch/x86/kernel/io_apic_64.c
  cpumask: Replace cpumask_of_cpu with cpumask_of_cpu_ptr
  Revert "cpumask: introduce new APIs"
  cpumask: make for_each_cpu_mask a bit smaller
  net: Pass reference to cpumask variable in net/sunrpc/svc.c
  ...

Fix up trivial conflicts in drivers/cpufreq/cpufreq.c manually
2008-07-23 18:37:44 -07:00
Linus Torvalds
d7b6de14a0 Merge branch 'core/softlockup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core/softlockup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  softlockup: fix invalid proc_handler for softlockup_panic
  softlockup: fix watchdog task wakeup frequency
  softlockup: fix watchdog task wakeup frequency
  softlockup: show irqtrace
  softlockup: print a module list on being stuck
  softlockup: fix NMI hangs due to lock race - 2.6.26-rc regression
  softlockup: fix false positives on nohz if CPU is 100% idle for more than 60 seconds
  softlockup: fix softlockup_thresh fix
  softlockup: fix softlockup_thresh unaligned access and disable detection at runtime
  softlockup: allow panic on lockup
2008-07-23 18:34:13 -07:00
Roland McGrath
86a1c34a92 x86_64 syscall audit fast-path
This adds a fast path for 64-bit syscall entry and exit when
TIF_SYSCALL_AUDIT is set, but no other kind of syscall tracing.
This path does not need to save and restore all registers as
the general case of tracing does.  Avoiding the iret return path
when syscall audit is enabled helps performance a lot.

Signed-off-by: Roland McGrath <roland@redhat.com>
2008-07-23 17:47:32 -07:00
Uwe Kleine-König
2db873211b set_irq_wake: fix return code and wake status tracking
Since 15a647eba9 set_irq_wake returned -ENXIO
if another device had it already enabled.  Zero is the right value to
return in this case.  Moreover the change to desc->status was not reverted
if desc->chip->set_wake returned an error.

Signed-off-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-23 09:35:53 -07:00
Linus Torvalds
6eaaaac974 Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  remove CONFIG_KMOD from core kernel code
  remove CONFIG_KMOD from lib
  remove CONFIG_KMOD from sparc64
  rework try_then_request_module to do less in non-modular kernels
  remove mention of CONFIG_KMOD from documentation
  make CONFIG_KMOD invisible
  modules: Take a shortcut for checking if an address is in a module
  module: turn longs into ints for module sizes
  Shrink struct module: CONFIG_UNUSED_SYMBOLS ifdefs
  module: reorder struct module to save space on 64 bit builds
  module: generic each_symbol iterator function
  module: don't use stop_machine for waiting rmmod
2008-07-22 13:17:15 -07:00
Linus Torvalds
53baaaa968 Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (79 commits)
  arm: bus_id -> dev_name() and dev_set_name() conversions
  sparc64: fix up bus_id changes in sparc core code
  3c59x: handle pci_name() being const
  MTD: handle pci_name() being const
  HP iLO driver
  sysdev: Convert the x86 mce tolerant sysdev attribute to generic attribute
  sysdev: Add utility functions for simple int/ulong variable sysdev attributes
  sysdev: Pass the attribute to the low level sysdev show/store function
  driver core: Suppress sysfs warnings for device_rename().
  kobject: Transmit return value of call_usermodehelper() to caller
  sysfs-rules.txt: reword API stability statement
  debugfs: Implement debugfs_remove_recursive()
  HOWTO: change email addresses of James in HOWTO
  always enable FW_LOADER unless EMBEDDED=y
  uio-howto.tmpl: use unique output names
  uio-howto.tmpl: use standard copyright/legal markings
  sysfs: don't call notify_change
  sysdev: fix debugging statements in registration code.
  kobject: should use kobject_put() in kset-example
  kobject: reorder kobject to save space on 64 bit builds
  ...
2008-07-22 13:13:47 -07:00
Atsushi Nemoto
5f17156fc5 Fix build on COMPAT platforms when CONFIG_EPOLL is disabled
Add missing cond_syscall() entry for compat_sys_epoll_pwait.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: Davide Libenzi <davidel@xmailserver.org>
Cc: <stable@kernel.org>		[2.6.25.x, 2.6.26.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-22 09:59:41 -07:00
Miao Xie
91cd4d6ef0 cpusets: fix wrong domain attr updates
Fix wrong domain attr updates, or we will always update the first sched
domain attr.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>	[2.6.26.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-22 09:59:41 -07:00
Johannes Berg
a1ef5adb4c remove CONFIG_KMOD from core kernel code
Always compile request_module when the kernel allows modules.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-22 19:24:31 +10:00
Rusty Russell
3a642e99ba modules: Take a shortcut for checking if an address is in a module
This patch keeps track of the boundaries of module allocation, in
order to speed up module_text_address().

Inspired by Arjan's version, which required arch-specific defines:

	Various pieces of the kernel (lockdep, latencytop, etc) tend
	to store backtraces, sometimes at a relatively high
	frequency. In itself this isn't a big performance deal (after
	all you're using diagnostics features), but there have been
	some complaints from people who have over 100 modules loaded
	that this is a tad too slow.

	This is due to the new backtracer code which looks at every
	slot on the stack to see if it's a kernel/module text address,
	so that's 1024 slots.  1024 times 100 modules... that's a lot
	of list walking.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-22 19:24:28 +10:00
Denys Vlasenko
2f0f2a334b module: turn longs into ints for module sizes
This shrinks module.o and each *.ko file.

And finally, structure members which hold length of module
code (four such members there) and count of symbols
are converted from longs to ints.

We cannot possibly have a module where 32 bits won't
be enough to hold such counts.

For one, module loading checks module size for sanity
before loading, so such insanely big module will fail
that test first.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-22 19:24:27 +10:00
Denys Vlasenko
f7f5b67557 Shrink struct module: CONFIG_UNUSED_SYMBOLS ifdefs
module.c and module.h conatains code for finding
exported symbols which are declared with EXPORT_UNUSED_SYMBOL,
and this code is compiled in even if CONFIG_UNUSED_SYMBOLS is not set
and thus there can be no EXPORT_UNUSED_SYMBOLs in modules anyway
(because EXPORT_UNUSED_SYMBOL(x) are compiled out to nothing then).

This patch adds required #ifdefs.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-22 19:24:27 +10:00
Rusty Russell
dafd0940c9 module: generic each_symbol iterator function
Introduce an each_symbol() iterator to avoid duplicating the knowledge
about the 5 different sections containing symbols.  Currently only
used by find_symbol(), but will be used by symbol_put_addr() too.

(Includes NULL ptr deref fix by Jiri Kosina <jkosina@suse.cz>)

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jiri Kosina <jkosina@suse.cz>
2008-07-22 19:24:26 +10:00
Rusty Russell
da39ba5e1d module: don't use stop_machine for waiting rmmod
rmmod has a little-used "-w" option, meaning that instead of failing if the
module is in use, it should block until the module becomes unused.

In this case, we don't need to use stop_machine: Max Krasnyansky
indicated that would be useful for SystemTap which loads/unloads new
modules frequently.

Cc: Max Krasnyansky <maxk@qualcomm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-22 19:24:25 +10:00
Andi Kleen
4a0b2b4dbe sysdev: Pass the attribute to the low level sysdev show/store function
This allow to dynamically generate attributes and share show/store
functions between attributes. Right now most attributes are generated
by special macros and lots of duplicated code. With the attribute
passed it's instead possible to attach some data to the attribute
and then use that in shared low level functions to do different things.

I need this for the dynamically generated bank attributes in the x86
machine check code, but it'll allow some further cleanups.

I converted all users in tree to the new show/store prototype. It's a single
huge patch to avoid unbisectable sections.

Runtime tested: x86-32, x86-64
Compiled only: ia64, powerpc
Not compile tested/only grep converted: sh, arm, avr32

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:55:02 -07:00
Ingo Molnar
ba42059fbd sched: hrtick_enabled() should use cpu_active()
Peter pointed out that hrtick_enabled() should use cpu_active().

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-20 11:02:06 +02:00
Ingo Molnar
d986434a7d Merge branch 'sched/urgent' into sched/devel 2008-07-20 11:01:29 +02:00
Peter Zijlstra
31656519e1 sched, x86: clean up hrtick implementation
random uvesafb failures were reported against Gentoo:

  http://bugs.gentoo.org/show_bug.cgi?id=222799

and Mihai Moldovan bisected it back to:

> 8f4d37ec07 is first bad commit
> commit 8f4d37ec07
> Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Date:   Fri Jan 25 21:08:29 2008 +0100
>
>    sched: high-res preemption tick

Linus suspected it to be hrtick + vm86 interaction and observed:

> Btw, Peter, Ingo: I think that commit is doing bad things. They aren't
> _incorrect_ per se, but they are definitely bad.
>
> Why?
>
> Using random _TIF_WORK_MASK flags is really impolite for doing
> "scheduling" work. There's a reason that arch/x86/kernel/entry_32.S
> special-cases the _TIF_NEED_RESCHED flag: we don't want to exit out of
> vm86 mode unnecessarily.
>
> See the "work_notifysig_v86" label, and how it does that
> "save_v86_state()" thing etc etc.

Right, I never liked having to fiddle with those TIF flags. Initially I
needed it because the hrtimer base lock could not nest in the rq lock.
That however is fixed these days.

Currently the only reason left to fiddle with the TIF flags is remote
wakeups. We cannot program a remote cpu's hrtimer. I've been thinking
about using the new and improved IPI function call stuff to implement
hrtimer_start_on().

However that does require that smp_call_function_single(.wait=0) works
from interrupt context - /me looks at the latest series from Jens - Yes
that does seem to be supported, good.

Here's a stab at cleaning this stuff up ...

Mihai reported test success as well.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Mihai Moldovan <ionic@ionic.de>
Cc: Michal Januszewski <spock@gentoo.org>
Cc: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-20 10:37:28 +02:00
Mike Travis
c18a41fbbc cpumask: Optimize cpumask_of_cpu in kernel/time/tick-common.c
* Optimize various places where a pointer to the cpumask_of_cpu value
    will result in reducing stack pressure.

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 22:02:59 +02:00
Mike Travis
65c0118453 cpumask: Replace cpumask_of_cpu with cpumask_of_cpu_ptr
* This patch replaces the dangerous lvalue version of cpumask_of_cpu
    with new cpumask_of_cpu_ptr macros.  These are patterned after the
    node_to_cpumask_ptr macros.

    In general terms, if there is a cpumask_of_cpu_map[] then a pointer to
    the cpumask_of_cpu_map[cpu] entry is used.  The cpumask_of_cpu_map
    is provided when there is a large NR_CPUS count, reducing
    greatly the amount of code generated and stack space used for
    cpumask_of_cpu().  The pointer to the cpumask_t value is needed for
    calling set_cpus_allowed_ptr() to reduce the amount of stack space
    needed to pass the cpumask_t value.

    If there isn't a cpumask_of_cpu_map[], then a temporary variable is
    declared and filled in with value from cpumask_of_cpu(cpu) as well as
    a pointer variable pointing to this temporary variable.  Afterwards,
    the pointer is used to reference the cpumask value.  The compiler
    will optimize out the extra dereference through the pointer as well
    as the stack space used for the pointer, resulting in identical code.

    A good example of the orthogonal usages is in net/sunrpc/svc.c:

	case SVC_POOL_PERCPU:
	{
		unsigned int cpu = m->pool_to[pidx];
		cpumask_of_cpu_ptr(cpumask, cpu);

		*oldmask = current->cpus_allowed;
		set_cpus_allowed_ptr(current, cpumask);
		return 1;
	}
	case SVC_POOL_PERNODE:
	{
		unsigned int node = m->pool_to[pidx];
		node_to_cpumask_ptr(nodecpumask, node);

		*oldmask = current->cpus_allowed;
		set_cpus_allowed_ptr(current, nodecpumask);
		return 1;
	}

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 22:02:57 +02:00
Ingo Molnar
bb2c018b09 Merge branch 'linus' into cpus4096
Conflicts:

	drivers/acpi/processor_throttling.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 22:00:54 +02:00
Hiroshi Shimamoto
4dca10a960 softlockup: fix invalid proc_handler for softlockup_panic
The type of softlockup_panic is int, but the proc_handler is
proc_doulongvec_minmax(). This handler is for unsigned long.

This handler should be proc_dointvec_minmax().

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 18:29:28 +02:00
David Howells
577b4a58d2 sched: fix warning in inc_rt_tasks() to not declare variable 'rq' if it's not needed
Fix inc_rt_tasks() to not declare variable 'rq' if it's not needed.  It is
declared if CONFIG_SMP or CONFIG_RT_GROUP_SCHED, but only used if CONFIG_SMP.

This is a consequence of patch 1f11eb6a8b plus
patch 1100ac91b6.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 13:56:03 +02:00
Max Krasnyansky
39b0fad712 cpu hotplug: Make cpu_active_map synchronization dependency clear
This goes on top of the cpu_active_map (take 2) patch.

Currently we depend on the stop_machine to provide nescessesary
synchronization for the cpu_active_map updates.
As Dmitry Adamushko pointed this is fragile and is not much clearer
than the previous scheme. In other words we do not want to depend on
the internal stop machine operation here.
So make the synchronization rules clear by doing synchronize_sched()
after clearing out cpu active bit.

Tested on quad-Core2 with:

   while true; do
      for i in 1 2 3; do
        echo 0 > /sys/devices/system/cpu/cpu$i/online
      done
      for i in 1 2 3; do
        echo 1 > /sys/devices/system/cpu/cpu$i/online
      done
   done
and
   stress -c 200

No lockdep, preempt or other complaints.

Signed-off-by: Max Krasnyansky <maxk@qualcomm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 13:23:18 +02:00
Max Krasnyansky
e761b77252 cpu hotplug, sched: Introduce cpu_active_map and redo sched domain managment (take 2)
This is based on Linus' idea of creating cpu_active_map that prevents
scheduler load balancer from migrating tasks to the cpu that is going
down.

It allows us to simplify domain management code and avoid unecessary
domain rebuilds during cpu hotplug event handling.

Please ignore the cpusets part for now. It needs some more work in order
to avoid crazy lock nesting. Although I did simplfy and unify domain
reinitialization logic. We now simply call partition_sched_domains() in
all the cases. This means that we're using exact same code paths as in
cpusets case and hence the test below cover cpusets too.
Cpuset changes to make rebuild_sched_domains() callable from various
contexts are in the separate patch (right next after this one).

This not only boots but also easily handles
	while true; do make clean; make -j 8; done
and
	while true; do on-off-cpu 1; done
at the same time.
(on-off-cpu 1 simple does echo 0/1 > /sys/.../cpu1/online thing).

Suprisingly the box (dual-core Core2) is quite usable. In fact I'm typing
this on right now in gnome-terminal and things are moving just fine.

Also this is running with most of the debug features enabled (lockdep,
mutex, etc) no BUG_ONs or lockdep complaints so far.

I believe I addressed all of the Dmitry's comments for original Linus'
version. I changed both fair and rt balancer to mask out non-active cpus.
And replaced cpu_is_offline() with !cpu_active() in the main scheduler
code where it made sense (to me).

Signed-off-by: Max Krasnyanskiy <maxk@qualcomm.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Gregory Haskins <ghaskins@novell.com>
Cc: dmitry.adamushko@gmail.com
Cc: pj@sgi.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 13:22:25 +02:00
Dmitry Adamushko
7ebefa8cee sched: rework of "prioritize non-migratable tasks over migratable ones"
(1) handle in a generic way all cases when a newly woken-up task is
not migratable (not just a corner case when "rt_se->nr_cpus_allowed ==
1")

(2) if current is to be preempted, then make sure "p" will be picked
up by pick_next_task_rt().
i.e. move task's group at the head of its list as well.

currently, it's not a case for the group-scheduling case as described
here: http://www.ussg.iu.edu/hypermail/linux/kernel/0807.0/0134.html

Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Gregory Haskins <ghaskins@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 12:55:14 +02:00
Mike Travis
13b40c1e40 sched: reduce stack size in isolated_cpu_setup()
* Remove 16k stack requirements in isolated_cpu_setup when NR_CPUS=4096.

Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 11:55:42 +02:00
Ingo Molnar
d88c169197 Revert parts of "ftrace: do not trace scheduler functions"
the removal of -mno-spe in the !ftrace case was not intended.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 08:59:24 +02:00
Ingo Molnar
393d81aa02 Merge branch 'linus' into xen-64bit 2008-07-17 23:57:20 +02:00
Linus Torvalds
bdec6cace4 Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  ftrace: do not trace library functions
  ftrace: do not trace scheduler functions
  ftrace: fix lockup with MAXSMP
  ftrace: fix merge buglet
2008-07-17 10:37:10 -07:00
Jeremy Fitzhardinge
93a0886e23 x86, xen, power: fix up config dependencies on PM
Xen save/restore needs bits of code enabled by PM_SLEEP, and PM_SLEEP
depends on PM.  So make XEN_SAVE_RESTORE depend on PM and PM_SLEEP
depend on XEN_SAVE_RESTORE.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-17 19:25:20 +02:00
Ingo Molnar
c349e0a01c ftrace: do not trace scheduler functions
do not trace scheduler functions - it's still a bit fragile
and can lock up with:

  http://redhat.com/~mingo/misc/config-Thu_Jul_17_13_34_52_CEST_2008

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-17 17:40:11 +02:00
Roland McGrath
666f164f4f fix dangling zombie when new parent ignores children
This fixes an arcane bug that we think was a regression introduced
by commit b2b2cbc4b2.  When a parent
ignores SIGCHLD (or uses SA_NOCLDWAIT), its children would self-reap
but they don't if it's using ptrace on them.  When the parent thread
later exits and ceases to ptrace a child but leaves other live
threads in the parent's thread group, any zombie children are left
dangling.  The fix makes them self-reap then, as they would have
done earlier if ptrace had not been in use.

Signed-off-by: Roland McGrath <roland@redhat.com>
2008-07-16 18:02:34 -07:00
Roland McGrath
14dd0b8141 do_wait: return security_task_wait() error code in place of -ECHILD
This reverts the effect of commit f2cc3eb133
"do_wait: fix security checks".  That change reverted the effect of commit
7324328446.  The rationale for the original
commit still stands.  The inconsistent treatment of children hidden by
ptrace was an unintended omission in the original change and in no way
invalidates its purpose.

This makes do_wait return the error returned by security_task_wait()
(usually -EACCES) in place of -ECHILD when there are some children the
caller would be able to wait for if not for the permission failure.  A
permission error will give the user a clue to look for security policy
problems, rather than for mysterious wait bugs.

Signed-off-by: Roland McGrath <roland@redhat.com>
2008-07-16 18:02:34 -07:00
Roland McGrath
f470021adb ptrace children revamp
ptrace no longer fiddles with the children/sibling links, and the
old ptrace_children list is gone.  Now ptrace, whether of one's own
children or another's via PTRACE_ATTACH, just uses the new ptraced
list instead.

There should be no user-visible difference that matters.  The only
change is the order in which do_wait() sees multiple stopped
children and stopped ptrace attachees.  Since wait_task_stopped()
was changed earlier so it no longer reorders the children list, we
already know this won't cause any new problems.

Signed-off-by: Roland McGrath <roland@redhat.com>
2008-07-16 18:02:33 -07:00
Roland McGrath
98abed0200 do_wait reorganization
This breaks out the guts of do_wait into three subfunctions.
The control flow is less nonobvious without so much goto.
do_wait_thread and ptrace_do_wait contain the main work of the outer loop.
wait_consider_task contains the main work of the inner loop.

Signed-off-by: Roland McGrath <roland@redhat.com>
2008-07-16 18:02:33 -07:00
Linus Torvalds
dc7c65db28 Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (72 commits)
  Revert "x86/PCI: ACPI based PCI gap calculation"
  PCI: remove unnecessary volatile in PCIe hotplug struct controller
  x86/PCI: ACPI based PCI gap calculation
  PCI: include linux/pm_wakeup.h for device_set_wakeup_capable
  PCI PM: Fix pci_prepare_to_sleep
  x86/PCI: Fix PCI config space for domains > 0
  Fix acpi_pm_device_sleep_wake() by providing a stub for CONFIG_PM_SLEEP=n
  PCI: Simplify PCI device PM code
  PCI PM: Introduce pci_prepare_to_sleep and pci_back_from_sleep
  PCI ACPI: Rework PCI handling of wake-up
  ACPI: Introduce new device wakeup flag 'prepared'
  ACPI: Introduce acpi_device_sleep_wake function
  PCI: rework pci_set_power_state function to call platform first
  PCI: Introduce platform_pci_power_manageable function
  ACPI: Introduce acpi_bus_power_manageable function
  PCI: make pci_name use dev_name
  PCI: handle pci_name() being const
  PCI: add stub for pci_set_consistent_dma_mask()
  PCI: remove unused arch pcibios_update_resource() functions
  PCI: fix pci_setup_device()'s sprinting into a const buffer
  ...

Fixed up conflicts in various files (arch/x86/kernel/setup_64.c,
arch/x86/pci/irq.c, arch/x86/pci/pci.h, drivers/acpi/sleep/main.c,
drivers/pci/pci.c, drivers/pci/pci.h, include/acpi/acpi_bus.h) from x86
and ACPI updates manually.
2008-07-16 17:25:46 -07:00