Commit graph

66 commits

Author SHA1 Message Date
Jason Baron
5d592b44b2 tracing: tracepoints for softirq entry/exit - add softirq-to-name array
Create a 'softirq_to_name' array, which is indexed by softirq #, so
that we can easily convert between the softirq index # and its name, in
order to get more meaningful output messages.

LKML-Reference: <20090312183336.GB3352@redhat.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
2009-03-12 21:15:02 -04:00
Yinghai Lu
4a046d1754 x86: arch_probe_nr_irqs
Impact: save RAM with large NR_CPUS, get smaller nr_irqs

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Mike Travis <travis@sgi.com>
2009-01-12 17:39:24 -08:00
Linus Torvalds
3610639d1f Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  hrtimer: splitout peek ahead functionality, fix
  hrtimer: fixup comments
  hrtimer: fix recursion deadlock by re-introducing the softirq
  hrtimer: simplify hotplug migration
  hrtimer: fix HOTPLUG_CPU=n compile warning
  hrtimer: splitout peek ahead functionality
2009-01-06 17:10:53 -08:00
Jesper Juhl
8c3659347e include/linux/interrupt.h: do not include linux/irqnr.h twice
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:14 -08:00
Peter Zijlstra
a6037b61c2 hrtimer: fix recursion deadlock by re-introducing the softirq
Impact: fix rare runtime deadlock

There are a few sites that do:

  spin_lock_irq(&foo)
  hrtimer_start(&bar)
    __run_hrtimer(&bar)
      func()
        spin_lock(&foo)

which obviously deadlocks. In order to avoid this, never call __run_hrtimer()
from hrtimer_start*() context, but instead defer this to softirq context.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-05 13:14:33 +01:00
Linus Torvalds
7d3b56ba37 Merge branch 'cpus4096-for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'cpus4096-for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (77 commits)
  x86: setup_per_cpu_areas() cleanup
  cpumask: fix compile error when CONFIG_NR_CPUS is not defined
  cpumask: use alloc_cpumask_var_node where appropriate
  cpumask: convert shared_cpu_map in acpi_processor* structs to cpumask_var_t
  x86: use cpumask_var_t in acpi/boot.c
  x86: cleanup some remaining usages of NR_CPUS where s/b nr_cpu_ids
  sched: put back some stack hog changes that were undone in kernel/sched.c
  x86: enable cpus display of kernel_max and offlined cpus
  ia64: cpumask fix for is_affinity_mask_valid()
  cpumask: convert RCU implementations, fix
  xtensa: define __fls
  mn10300: define __fls
  m32r: define __fls
  h8300: define __fls
  frv: define __fls
  cris: define __fls
  cpumask: CONFIG_DISABLE_OBSOLETE_CPUMASK_FUNCTIONS
  cpumask: zero extra bits in alloc_cpumask_var_node
  cpumask: replace for_each_cpu_mask_nr with for_each_cpu in kernel/time/
  cpumask: convert mm/
  ...
2009-01-03 12:04:39 -08:00
Linus Torvalds
b840d79631 Merge branch 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (66 commits)
  x86: export vector_used_by_percpu_irq
  x86: use logical apicid in x2apic_cluster's x2apic_cpu_mask_to_apicid_and()
  sched: nominate preferred wakeup cpu, fix
  x86: fix lguest used_vectors breakage, -v2
  x86: fix warning in arch/x86/kernel/io_apic.c
  sched: fix warning in kernel/sched.c
  sched: move test_sd_parent() to an SMP section of sched.h
  sched: add SD_BALANCE_NEWIDLE at MC and CPU level for sched_mc>0
  sched: activate active load balancing in new idle cpus
  sched: bias task wakeups to preferred semi-idle packages
  sched: nominate preferred wakeup cpu
  sched: favour lower logical cpu number for sched_mc balance
  sched: framework for sched_mc/smt_power_savings=N
  sched: convert BALANCE_FOR_xx_POWER to inline functions
  x86: use possible_cpus=NUM to extend the possible cpus allowed
  x86: fix cpu_mask_to_apicid_and to include cpu_online_mask
  x86: update io_apic.c to the new cpumask code
  x86: Introduce topology_core_cpumask()/topology_thread_cpumask()
  x86: xen: use smp_call_function_many()
  x86: use work_on_cpu in x86/kernel/cpu/mcheck/mce_amd_64.c
  ...

Fixed up trivial conflict in kernel/time/tick-sched.c manually
2009-01-02 11:44:09 -08:00
Rusty Russell
d036e67b40 cpumask: convert kernel/irq
Impact: Reduce stack usage, use new cpumask API.  ALPHA mod!

Main change is that irq_default_affinity becomes a cpumask_var_t, so
treat it as a pointer (this effects alpha).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-01-01 10:12:26 +10:30
Linus Torvalds
db200df0b3 Merge branch 'irq-fixes-for-linus-4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'irq-fixes-for-linus-4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  sparseirq: move __weak symbols into separate compilation unit
  sparseirq: work around __weak alias bug
  sparseirq: fix hang with !SPARSE_IRQ
  sparseirq: set lock_class for legacy irq when sparse_irq is selected
  sparseirq: work around compiler optimizing away __weak functions
  sparseirq: fix desc->lock init
  sparseirq: do not printk when migrating IRQ descriptors
  sparseirq: remove duplicated arch_early_irq_init()
  irq: simplify for_each_irq_desc() usage
  proc: remove ifdef CONFIG_SPARSE_IRQ from stat.c
  irq: for_each_irq_desc() move to irqnr.h
  hrtimer: remove #include <linux/irq.h>
2008-12-31 09:00:59 -08:00
Rusty Russell
2ca1a61583 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:

	arch/x86/kernel/io_apic.c
2008-12-31 23:05:57 +10:30
Linus Torvalds
179475a3b4 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, sparseirq: clean up Kconfig entry
  x86: turn CONFIG_SPARSE_IRQ off by default
  sparseirq: fix numa_migrate_irq_desc dependency and comments
  sparseirq: add kernel-doc notation for new member in irq_desc, -v2
  locking, irq: enclose irq_desc_lock_class in CONFIG_LOCKDEP
  sparseirq, xen: make sure irq_desc is allocated for interrupts
  sparseirq: fix !SMP building, #2
  x86, sparseirq: move irq_desc according to smp_affinity, v7
  proc: enclose desc variable of show_stat() in CONFIG_SPARSE_IRQ
  sparse irqs: add irqnr.h to the user headers list
  sparse irqs: handle !GENIRQ platforms
  sparseirq: fix !SMP && !PCI_MSI && !HT_IRQ build
  sparseirq: fix Alpha build failure
  sparseirq: fix typo in !CONFIG_IO_APIC case
  x86, MSI: pass irq_cfg and irq_desc
  x86: MSI start irq numbering from nr_irqs_gsi
  x86: use NR_IRQS_LEGACY
  sparse irq_desc[] array: core kernel and x86 changes
  genirq: record IRQ_LEVEL in irq_desc[]
  irq.h: remove padding from irq_desc on 64bits
2008-12-30 16:20:19 -08:00
Yinghai Lu
43a256322a sparseirq: move __weak symbols into separate compilation unit
GCC has a bug with __weak alias functions: if the functions are in
the same compilation unit as their call site, GCC can decide to
inline them - and thus rob the linker of the opportunity to override
the weak alias with the real thing.

So move all the IRQ handling related __weak symbols to kernel/irq/chip.c.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-29 12:15:49 +01:00
Rusty Russell
968ea6d80e Merge ../linux-2.6-x86
Conflicts:

	arch/x86/kernel/io_apic.c
	kernel/sched.c
	kernel/sched_stats.h
2008-12-13 21:55:51 +10:30
Rusty Russell
0de26520c7 cpumask: make irq_set_affinity() take a const struct cpumask
Impact: change existing irq_chip API

Not much point with gentle transition here: the struct irq_chip's
setaffinity method signature needs to change.

Fortunately, not widely used code, but hits a few architectures.

Note: In irq_select_affinity() I save a temporary in by mangling
irq_desc[irq].affinity directly.  Ingo, does this break anything?

(Folded in fix from KOSAKI Motohiro)

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Reviewed-by: Grant Grundler <grundler@parisc-linux.org>
Acked-by: Ingo Molnar <mingo@redhat.com>
Cc: ralf@linux-mips.org
Cc: grundler@parisc-linux.org
Cc: jeremy@xensource.com
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
2008-12-13 21:20:26 +10:30
Ingo Molnar
0ebb26e7a4 sparse irqs: handle !GENIRQ platforms
Impact: build fix

fix:

 In file included from /home/mingo/tip/arch/m68k/amiga/amiints.c:39:
 /home/mingo/tip/include/linux/interrupt.h:21: error: expected identifier or '('
 /home/mingo/tip/arch/m68k/amiga/amiints.c: In function 'amiga_init_IRQ':

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-12 12:28:50 +01:00
Yinghai Lu
0b8f1efad3 sparse irq_desc[] array: core kernel and x86 changes
Impact: new feature

Problem on distro kernels: irq_desc[NR_IRQS] takes megabytes of RAM with
NR_CPUS set to large values. The goal is to be able to scale up to much
larger NR_IRQS value without impacting the (important) common case.

To solve this, we generalize irq_desc[NR_IRQS] to an (optional) array of
irq_desc pointers.

When CONFIG_SPARSE_IRQ=y is used, we use kzalloc_node to get irq_desc,
this also makes the IRQ descriptors NUMA-local (to the site that calls
request_irq()).

This gets rid of the irq_cfg[] static array on x86 as well: irq_cfg now
uses desc->chip_data for x86 to store irq_cfg.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-08 14:31:51 +01:00
Peter Zijlstra
ca109491f6 hrtimer: removing all ur callback modes
Impact: cleanup, move all hrtimer processing into hardirq context

This is an attempt at removing some of the hrtimer complexity by
reducing the number of callback modes to 1.

This means that all hrtimer callback functions will be ran from HARD-irq
context.

I went through all the 30 odd hrtimer callback functions in the kernel
and saw only one that I'm not quite sure of, which is the one in
net/can/bcm.c - hence I'm CC-ing the folks responsible for that code.

Furthermore, the hrtimer core now calls callbacks directly with IRQs
disabled in case you try to enqueue an expired timer. If this timer is a
periodic timer (which should use hrtimer_forward() to advance its time)
then it might be possible to end up in an inf. recursive loop due to the
fact that hrtimer_forward() doesn't round up to the next timer
granularity, and therefore keeps on calling the callback - obviously
this needs a fix.

Aside from that, this seems to compile and actually boot on my dual core
test box - although I'm sure there are some bugs in, me not hitting any
makes me certain :-)

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-25 15:45:46 +01:00
Linus Torvalds
9301975ec2 Merge branch 'genirq-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
This merges branches irq/genirq, irq/sparseirq-v4, timers/hpet-percpu
and x86/uv.

The sparseirq branch is just preliminary groundwork: no sparse IRQs are
actually implemented by this tree anymore - just the new APIs are added
while keeping the old way intact as well (the new APIs map 1:1 to
irq_desc[]).  The 'real' sparse IRQ support will then be a relatively
small patch ontop of this - with a v2.6.29 merge target.

* 'genirq-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (178 commits)
  genirq: improve include files
  intr_remapping: fix typo
  io_apic: make irq_mis_count available on 64-bit too
  genirq: fix name space collisions of nr_irqs in arch/*
  genirq: fix name space collision of nr_irqs in autoprobe.c
  genirq: use iterators for irq_desc loops
  proc: fixup irq iterator
  genirq: add reverse iterator for irq_desc
  x86: move ack_bad_irq() to irq.c
  x86: unify show_interrupts() and proc helpers
  x86: cleanup show_interrupts
  genirq: cleanup the sparseirq modifications
  genirq: remove artifacts from sparseirq removal
  genirq: revert dynarray
  genirq: remove irq_to_desc_alloc
  genirq: remove sparse irq code
  genirq: use inline function for irq_to_desc
  genirq: consolidate nr_irqs and for_each_irq_desc()
  x86: remove sparse irq from Kconfig
  genirq: define nr_irqs for architectures with GENERIC_HARDIRQS=n
  ...
2008-10-20 13:23:01 -07:00
Thomas Gleixner
dd3a1db900 genirq: improve include files
Move the irq_desc related iterators out of irq.h, into irqnr.h, also
available via interrupt.h.

This way non-genirq (and even non-hardirq) architectures get the
common definitions and iterators.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-18 14:05:18 +02:00
David S. Miller
54514a70ad softirq: Add support for triggering softirq work on softirqs.
This is basically a genericization of Jens Axboe's block layer
remote softirq changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-17 08:46:56 +02:00
Thomas Gleixner
70dd4d992a genirq: consolidate nr_irqs and for_each_irq_desc()
Move all of those to linux/irq.h where they belong.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-10-16 16:53:14 +02:00
Thomas Gleixner
7ef0c30dbf genirq: define nr_irqs for architectures with GENERIC_HARDIRQS=n
Revert the sparse irq changes in m68k/s390/sparc and just define
nr_irqs as NR_IRQS for those architectures.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-10-16 16:53:14 +02:00
Yinghai Lu
c7fb03a475 irq, fs/proc: replace loop with nr_irqs for proc/stat
Replace another nr_irqs loop to avoid the allocation of all sparse
irq entries - use for_each_irq_desc instead.

v2: make sure arch without GENERIC_HARDIRQS works too

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16 16:52:33 +02:00
Yinghai Lu
85c0f90978 irq: introduce nr_irqs
at this point nr_irqs is equal NR_IRQS

convert a few easy users from NR_IRQS to dynamic nr_irqs.

v2: according to Eric, we need to take care of arch without generic_hardirqs

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16 16:52:05 +02:00
Alexey Dobriyan
978b0116cd softirq: allocate less vectors
We don't need whole 32 of them, only NR_SOFTIRQS.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-06 20:04:36 +02:00
Mark Asselstine
f6ac436dcc Remove the deprecated cli() sti() functions
These functions have been deprecated for some time now but remained until
all legacy callers could be removed.  With a few commits in 2.6.26 this
has happened so now we can remove these deprecated functions.

Signed-off-by: Mark Asselstine <mark.asselstine@windriver.com>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-05 14:33:48 -07:00
Linus Torvalds
61d97f4fcf Merge branch 'genirq' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'genirq' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  genirq: remove extraneous checks in manage.c
  genirq: Expose default irq affinity mask (take 3)
2008-07-15 10:39:22 -07:00
Max Krasnyansky
1840475676 genirq: Expose default irq affinity mask (take 3)
Current IRQ affinity interface does not provide a way to set affinity
for the IRQs that will be allocated/activated in the future.
This patch creates /proc/irq/default_smp_affinity that lets users set
default affinity mask for the newly allocated IRQs. Changing the default
does not affect affinity masks for the currently active IRQs, they
have to be changed explicitly.

Updated based on Paul J's comments and added some more documentation.

Signed-off-by: Max Krasnyansky <maxk@qualcomm.com>
Cc: pj@sgi.com
Cc: a.p.zijlstra@chello.nl
Cc: tglx@linutronix.de
Cc: rdunlap@xenotime.net
Cc: mingo@elte.hu
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-06-05 15:18:30 +02:00
Carlos R. Mafra
962cf36c5b Remove argument from open_softirq which is always NULL
As git-grep shows, open_softirq() is always called with the last argument
being NULL

block/blk-core.c:       open_softirq(BLOCK_SOFTIRQ, blk_done_softirq, NULL);
kernel/hrtimer.c:       open_softirq(HRTIMER_SOFTIRQ, run_hrtimer_softirq, NULL);
kernel/rcuclassic.c:    open_softirq(RCU_SOFTIRQ, rcu_process_callbacks, NULL);
kernel/rcupreempt.c:    open_softirq(RCU_SOFTIRQ, rcu_process_callbacks, NULL);
kernel/sched.c: open_softirq(SCHED_SOFTIRQ, run_rebalance_domains, NULL);
kernel/softirq.c:       open_softirq(TASKLET_SOFTIRQ, tasklet_action, NULL);
kernel/softirq.c:       open_softirq(HI_SOFTIRQ, tasklet_hi_action, NULL);
kernel/timer.c: open_softirq(TIMER_SOFTIRQ, run_timer_softirq, NULL);
net/core/dev.c: open_softirq(NET_TX_SOFTIRQ, net_tx_action, NULL);
net/core/dev.c: open_softirq(NET_RX_SOFTIRQ, net_rx_action, NULL);

This observation has already been made by Matthew Wilcox in June 2002
(http://www.cs.helsinki.fi/linux/linux-kernel/2002-25/0687.html)

"I notice that none of the current softirq routines use the data element
passed to them."

and the situation hasn't changed since them. So it appears we can safely
remove that extra argument to save 128 (54) bytes of kernel data (text).

Signed-off-by: Carlos R. Mafra <crmafra@ift.unesp.br>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-25 07:43:15 +02:00
Adrian Bunk
eb0f1c442d proper __do_softirq() prototype
Add a proper prototype for __do_softirq() in include/linux/interrupt.h

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:02 -07:00
Russell King
d7b906897e [S390] genirq/clockevents: move irq affinity prototypes/inlines to interrupt.h
> Generic code is not supposed to include irq.h. Replace this include
> by linux/hardirq.h instead and add/replace an include of linux/irq.h
> in asm header files where necessary.
> This change should only matter for architectures that make use of
> GENERIC_CLOCKEVENTS.
> Architectures in question are mips, x86, arm, sh, powerpc, uml and sparc64.
>
> I did some cross compile tests for mips, x86_64, arm, powerpc and sparc64.
> This patch fixes also build breakages caused by the include replacement in
> tick-common.h.

I generally dislike adding optional linux/* includes in asm/* includes -
I'm nervous about this causing include loops.

However, there's a separate point to be discussed here.

That is, what interfaces are expected of every architecture in the kernel.
If generic code wants to be able to set the affinity of interrupts, then
that needs to become part of the interfaces listed in linux/interrupt.h
rather than linux/irq.h.

So what I suggest is this approach instead (against Linus' tree of a
couple of days ago) - we move irq_set_affinity() and irq_can_set_affinity()
to linux/interrupt.h, change the linux/irq.h includes to linux/interrupt.h
and include asm/irq_regs.h where needed (asm/irq_regs.h is supposed to be
rarely used include since not much touches the stacked parent context
registers.)

Build tested on ARM PXA family kernels and ARM's Realview platform
kernels which both use genirq.

[ tglx@linutronix.de: add GENERIC_HARDIRQ dependencies ]

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-04-17 07:47:05 +02:00
Harvey Harrison
b3c9752868 include/linux: Remove all users of FASTCALL() macro
FASTCALL() is always expanded to empty, remove it.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-13 16:21:18 -08:00
Adrian Bunk
f74596d079 proper show_interrupts() prototype
Add a proper prototype for show_interrupts() in include/linux/interrupt.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>
2008-02-06 10:41:02 -08:00
Dipankar Sarma
c2d727aa2f Preempt-RCU: Use softirq instead of tasklets for
This patch makes RCU use softirq instead of tasklets.

It also adds a memory barrier after raising the softirq
inorder to ensure that the cpu sees the most recently updated
value of rcu->cur while processing callbacks.
The discussion of the related theoretical race pointed out
by James Huang can be found here --> http://lkml.org/lkml/2007/11/20/603

Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Reviewed-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-25 21:08:23 +01:00
Ahmed S. Darwish
b4471cbb09 Completely remove deprecated IRQ flags (SA_*)
Only very little files use the deprecated SA_* IRQ flags in latest pull.  This
patch series removes such macros from the tree and transfrom old code to the
new IRQF_* flags.

I've grepped the whole tree to make sure that no more files than the patched
ones use such deprecated macros.  I hope this series won't introduce build
errors.

Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Matthew Wilcox <willy@debian.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:43:00 -07:00
Guennadi Liakhovetski
aa5346a212 provide stubs for enable_irq_wake() and disable_irq_wake()
Provide {enable,disable}_irq_wakeup dummies for undefined
cross-compilers for platforms without CONFIG_GENERIC_IRQ.

Needed by wake-up-from-a-serial-port.patch

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:42:50 -07:00
Al Viro
0af3678f7c rip some includes from linux/interrupt.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-28 19:42:22 -07:00
Al Viro
e9ed7e722e take declarations of enable_irq() et.al. to linux/interrupt.h
Now that the last inlined instances are gone, all that is left to do
is turning disable_irq_nosync on arm26 and m68k from defines to aliases
and we are all set - we can make these externs in linux/interrupt.h
uncoditional and kill remaining instances in asm/irq.h

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-22 11:44:00 -07:00
Benjamin Herrenschmidt
2d3fbbb391 Add hard_irq_disable()
Some architectures, like powerpc, implement lazy disabling of interrupts.
That means that on those, local_irq_disable() doesn't actually disable
interrupts on the CPU, but only sets some per CPU flag which cause them to be
disabled only if an interrupt actually occurs.

However, in some cases, such as stop_machine, we really want interrupts to be
fully disabled.  For example, I have code using stop machine to do ECC error
injection, used to verify operations of the ECC hardware, that sort of thing.
It really needs to make sure that nothing is actually writing to memory while
the injection happens.  Similar examples can be found in other low level bits
and pieces.

This patch implements a generic hard_irq_disable() function which is meant to
be called -after- local_irq_disable() and ensures that interrupts are fully
disabled on that CPU.  The default implementation is a nop, though powerpc
does already provide an appropriate one.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-11 08:29:34 -07:00
Bernhard Walle
d85a60d85e Add IRQF_IRQPOLL flag (common code)
irqpoll is broken on some architectures that don't use the IRQ 0 for the timer
interrupt like IA64.  This patch adds a IRQF_IRQPOLL flag.

Each architecture is handled in a separate pach.  As I left the irq == 0 as
condition, this should not break existing architectures that use timer_irq ==
0 and that I did't address with that patch (because I don't know).

This patch:

This patch adds a IRQF_IRQPOLL flag that the interrupt registration code could
use for the interrupt it wants to use for IRQ polling.

Because this must not be the timer interrupt, an additional flag was added
instead of re-using the IRQF_TIMER constant.  Until all architectures will
have an IRQF_IRQPOLL interrupt, irq == 0 will stay as alternative as it should
not break anything.

Also, note_interrupt() is called on CPU-specific interrupts to be used as
interrupt source for IRQ polling.

Signed-off-by: Bernhard Walle <bwalle@suse.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Matthew Wilcox <willy@debian.org>
Cc: Grant Grundler <grundler@google.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:22 -07:00
Thomas Gleixner
0e8638e2ac Deprecate SA_xxx interrupt flags -V2
The deprecation of the SA_xxx interrupt flags did not emit deprecated
warnings. Andrew said about the removal of the deprecated flag defines:

> This is going to break a lot of external stuff.  We should have found
> a way to make usage of SA_* emit deprecated warnings (or _some_
> warning) to warn people of impending doom.  But I can't immediately
> find a way of doing that. if we _can_ find a way of doing this, I
> suspect we'll need to do it, and give people another six months.  It's
> going to get ugly out there.  We shall see...

Define the deprecated flags as a call to a __deprecated inline function
so a warning is emitted on compile time.

Extend the reprieve of out of tree drivers to 9/2007.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:08 -07:00
Monakhov Dmitriy
616883df78 IRQ: add __must_check to request_irq
This could help to find buggy drivers where request_irq return value wasn't
checked.  There's just no reason to ignore errors which can and do occur.
Anyone who got warning during compilation have to realise what it is't
realy safe code.

Signed-off-by: Monakhov Dmitriy <dmonakhov@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:00 -07:00
Roman Zippel
b3e2fd9ceb lockdep: Add missing disable/enable irq variant
Add missing disable/enable irq variant

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-04 17:59:06 -07:00
Andrew Morton
6168a702ab [PATCH] Declare init_irq_proc before we use it.
powerpc gets:

init/main.c: In function `do_basic_setup':
init/main.c:714: warning: implicit declaration of function `init_irq_proc'

but we cannot include linux/irq.h in generic code.

Fix it by moving the declaration into linux/interrupt.h instead.

And make sure all code that defines init_irq_proc() is including
linux/interrupt.h.

And nuke an ifdef-in-C

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-19 14:21:50 -08:00
Thomas Gleixner
54cdfdb47f [PATCH] hrtimers: add high resolution timer support
Implement high resolution timers on top of the hrtimers infrastructure and the
clockevents / tick-management framework.  This provides accurate timers for
all hrtimer subsystem users.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 08:13:59 -08:00
Thomas Gleixner
950f4427c2 [PATCH] Add irq flag to disable balancing for an interrupt
Add a flag so we can prevent the irq balancing of an interrupt.  Move the
bits, so we have room for more :)

Necessary for the ability to setup clocksources more flexible (e.g.  use the
different HPET channels per CPU)

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-16 08:13:56 -08:00
Tejun Heo
9ac7849e35 devres: device resource management
Implement device resource management, in short, devres.  A device
driver can allocate arbirary size of devres data which is associated
with a release function.  On driver detach, release function is
invoked on the devres data, then, devres data is freed.

devreses are typed by associated release functions.  Some devreses are
better represented by single instance of the type while others need
multiple instances sharing the same release function.  Both usages are
supported.

devreses can be grouped using devres group such that a device driver
can easily release acquired resources halfway through initialization
or selectively release resources (e.g. resources for port 1 out of 4
ports).

This patch adds devres core including documentation and the following
managed interfaces.

* alloc/free	: devm_kzalloc(), devm_kzfree()
* IO region	: devm_request_region(), devm_release_region()
* IRQ		: devm_request_irq(), devm_free_irq()
* DMA		: dmam_alloc_coherent(), dmam_free_coherent(),
		  dmam_declare_coherent_memory(), dmam_pool_create(),
		  dmam_pool_destroy()
* PCI		: pcim_enable_device(), pcim_pin_device(), pci_is_managed()
* iomap		: devm_ioport_map(), devm_ioport_unmap(), devm_ioremap(),
		  devm_ioremap_nocache(), devm_iounmap(), pcim_iomap_table(),
		  pcim_iomap(), pcim_iounmap()

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-02-09 17:39:36 -05:00
Christoph Lameter
c9819f4593 [PATCH] sched: use softirq for load balancing
Call rebalance_tick (renamed to run_rebalance_domains) from a newly introduced
softirq.

We calculate the earliest time for each layer of sched domains to be rescanned
(this is the rescan time for idle) and use the earliest of those to schedule
the softirq via a new field "next_balance" added to struct rq.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Peter Williams <pwil3058@bigpond.net.au>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Cc: "Chen, Kenneth W" <kenneth.w.chen@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-10 09:55:42 -08:00
Andrew Morton
676dcb8bc2 [PATCH] add bottom_half.h
With CONFIG_SMP=n:

  drivers/input/ff-memless.c:384: warning: implicit declaration of function 'local_bh_disable'
  drivers/input/ff-memless.c:393: warning: implicit declaration of function 'local_bh_enable'

Really linux/spinlock.h should include linux/interrupt.h.  But interrupt.h
includes sched.h which will need spinlock.h.

So the patch breaks the _bh declarations out into a separate header and
includes it in both interrupt.h and spinlock.h.

Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Cc: Andi Kleen <ak@suse.de>
Cc: <stable@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:20 -08:00
David Howells
7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00