Commit Graph

535 Commits

Author SHA1 Message Date
Yinghai Lu ed4dea6e0e genirq: Use IRQ_BITMAP_BITS as search size in irq_alloc_descs()
The runtime expansion of nr_irqs does not take into account that
bitmap_find_next_zero_area() returns "start" + size in case the search
for an matching zero area fails. That results in a start value which
can be completely off and is not covered by the following
expand_nr_irqs() and possibly outside of the absolute limit. But we
use it without further checking.

Use IRQ_BITMAP_BITS as the limit for the bitmap search and expand
nr_irqs when the start bit is beyond nr_irqs. So start is always
pointing to the correct area in the bitmap. nr_irqs is just the limit
for irq enumerations, not the real limit for the irq space.

[ tglx: Let irq_expand_nr_irqs() take the new upper end so we do not
  	expand nr_irqs more than necessary. Made changelog readable ]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4D6014F9.8040605@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-21 21:20:00 +01:00
Thomas Gleixner a61d825808 genirq: Fix misplaced status update in irq_disable()
We lazy disable interrupt lines, so only mark the line masked, when
the chip provides an irq_disable callback.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-21 21:19:59 +01:00
Thomas Gleixner a439520f8b genirq: Implement irq_data based move_*_irq() versions
No need to lookup the irq descriptor when calling from a chip callback
function which has irq_data already handy.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:25 +01:00
Thomas Gleixner 77694b408a genirq; Add fasteoi irq_chip quirk
Some chips want irq_eoi() only called when an interrupt is actually
handled. So they have checks for INPROGRESS and DISABLED in their
irq_eoi callbacks. Add a chip flag, which allows to handle that in the
generic code. No impact on the fastpath.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:24 +01:00
Thomas Gleixner 781295762d genirq: Add preflow handler support
sparc64 needs to call a preflow handler on certain interrupts befor
calling the action chain. Integrate it into handle_fasteoi_irq. Must
be enabled via CONFIG_IRQ_FASTEOI_PREFLOW. No impact when disabled.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David S. Miller <davem@davemloft.net>
2011-02-19 12:58:24 +01:00
Thomas Gleixner 3836ca08aa genirq: Consolidate set_chip_handler functions
No need to have separate functions if we have one plus inline wrappers.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:23 +01:00
Thomas Gleixner 02725e7471 genirq: Use irq_get/put functions
Convert the management functions to use the common irq_get/put
function.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:23 +01:00
Thomas Gleixner d5eb4ad2df genirq: Implement irq_get/put_desc_[bus]locked/unlock()
Most of the managing functions get the irq descriptor and lock it -
either with or without buslock. Instead of open coding this over and
over provide a common function to do that.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:23 +01:00
Thomas Gleixner 091738a266 genirq: Remove real old transition functions
These transition helpers are stale for years now. Remove them.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:23 +01:00
Thomas Gleixner a6967caf00 genirq: Remove desc->status when GENERIC_HARDIRQS_NO_COMPAT=y
If everything uses the right accessors, then enabling
GENERIC_HARDIRQS_NO_COMPAT should just work. If not it will tell you.

Don't be lazy and use the trick which I use in the core code!

git grep status_use_accessors

will unearth it in a split second. Offenders are tracked down and not
slapped with stinking trouts. This time we use frozen shark for a
better educational value.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:22 +01:00
Thomas Gleixner e1ef824146 genirq: Reflect IRQ_MOVE_PCNTXT in irq_data state
Required by x86.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:22 +01:00
Thomas Gleixner 7f94226f03 genirq: Move wakeup state to irq_data
Some irq_chips need to know the state of wakeup mode for
setting the trigger type etc. Reflect it in irq_data state.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:22 +01:00
Thomas Gleixner d4d5e08960 genirq: Add IRQCHIP_SET_TYPE_MASKED flag
irq_chips, which require to mask the chip before changing the trigger
type should set this flag. So the core takes care of it and the
requirement for looking into desc->status in the chip goes away.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
2011-02-19 12:58:22 +01:00
Thomas Gleixner 5d4d8fc9ac genirq: Cleanup irq.h
Put the constants into an enum and document them.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:21 +01:00
Thomas Gleixner f9e4989eb8 genirq: Force wrapped access to desc->status in core code
Force the usage of wrappers by another nasty CPP substitution.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:21 +01:00
Thomas Gleixner 1ccb4e612f genirq: Wrap the remaning IRQ_* flags
Use wrappers to keep them away from the core code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:21 +01:00
Thomas Gleixner 876dbd4cc1 genirq: Mirror irq trigger type bits in irq_data.state
That's the data structure chip functions get provided. Also allow them
to signal the core code that they updated the flags in irq_data.state
by returning IRQ_SET_MASK_OK_NOCOPY. The default is unchanged.

The type bits should be accessed via:

val = irqd_get_trigger_type(irqdata);
and
irqd_set_trigger_type(irqdata, val);

Coders who access them directly will be tracked down and slapped with
stinking trouts.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:20 +01:00
Thomas Gleixner 2bdd10558c genirq: Move IRQ_AFFINITY_SET to core
Keep status in sync until last abuser is gone.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:20 +01:00
Thomas Gleixner bce43032ad genirq: Reuse existing can set affinty check
Add a !desc check while at it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:20 +01:00
Thomas Gleixner a005677b3d genirq: Mirror IRQ_PER_CPU and IRQ_NO_BALANCING in irq_data.state
That's the right data structure to look at for arch code.

Accessor functions are provided.

	 irqd_is_per_cpu(irqdata);
	 irqd_can_balance(irqdata);

Coders who access them directly will be tracked down and slapped with
stinking trouts.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:20 +01:00
Thomas Gleixner 1ce6068dac genirq: Move debug code to separate header
It'll break when I'm going to undefine the constants.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:19 +01:00
Thomas Gleixner fae581e588 genirq: Remove CHECK_IRQ_PER_CPU from core code
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:19 +01:00
Thomas Gleixner 6a58fb3bad genirq: Remove CONFIG_IRQ_PER_CPU
The saving of this switch is minimal versus the ifdef mess it
creates. Simple enable PER_CPU unconditionally and remove the config
switch.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:19 +01:00
Thomas Gleixner f230b6d5c4 genirq: Add IRQ_MOVE_PENDING to irq_data.state
chip implementations need to know about it. Keep status in sync until
all users are fixed. 

Accessor function: irqd_is_setaffinity_pending(irqdata)

Coders who access them directly will be tracked down and slapped with
stinking trouts.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:18 +01:00
Thomas Gleixner 6d2cd17fde genirq: Move IRQ_WAKEUP to core
No users outside of core.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:18 +01:00
Thomas Gleixner c531e8361f genirq: Move IRQ_SUSPENDED to core
No users outside of core.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:18 +01:00
Thomas Gleixner 6e40262ea4 genirq: Move IRQ_MASKED to core
Keep status in sync until all users are fixed.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:17 +01:00
Thomas Gleixner 2a0d6fb335 genirq: Move IRQ_PENDING flag to core
Keep status in sync until all users are fixed.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:17 +01:00
Thomas Gleixner c1594b77e4 genirq: Move IRQ_DISABLED to core
Keep status in sync until all abusers are fixed.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:17 +01:00
Thomas Gleixner 163ef30911 genirq: Move IRQ_REPLAY and IRQ_WAITING to core
No users outside of core.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:16 +01:00
Thomas Gleixner 3d67baec7f genirq: Move IRQ_ONESHOT to core
No users outside of core.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:16 +01:00
Thomas Gleixner 009b4c3b8a genirq: Add IRQ_INPROGRESS to core
We need to maintain the flag for now in both fields status and istate.
Add a CONFIG_GENERIC_HARDIRQS_NO_COMPAT switch to allow testing w/o
the status one. Wrap the access to status IRQ_INPROGRESS in a inline
which can be turned of with CONFIG_GENERIC_HARDIRQS_NO_COMPAT along
with the define.

There is no reason that anything outside of core looks at this. That
needs some modifications, but we'll get there.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:16 +01:00
Thomas Gleixner 6954b75b48 genirq: Move IRQ_POLL_INPROGRESS to core
No users outside of core.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:15 +01:00
Thomas Gleixner 6f91a52d9b genirq: Use modify_status for set_irq_nested_thread
No need for a separate function in the core code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:15 +01:00
Thomas Gleixner 7acdd53e5b genirq: Move IRQ_SPURIOUS_DISABLED to core state
No users outside.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:15 +01:00
Thomas Gleixner bd062e7667 genirq: Move IRQ_AUTODETECT to internal state
No users outside of core

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:15 +01:00
Thomas Gleixner e6bea9c404 genirq: Protect tglx from tripping over his own feet
The irq_desc.status field will either go away or renamed to
settings. Anyway we need to maintain compatibility to avoid breaking
the world and some more. While moving bits into the core, I need to
avoid that I use any of the still existing IRQ_ bits in the core code
by typos. So that file will hold the inline wrappers and some nasty
CPP tricks to break the build when typoed.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:14 +01:00
Thomas Gleixner dbec07bac6 genirq: Add internal state field to irq_desc
That field will contain internal state information which is not going
to be exposed to anything outside the core code - except via accessor
functions. I'm tired of everyone fiddling in irq_desc.status.

core_internal_state__do_not_mess_with_it is clear enough, annoying to
type and easy to grep for. Offenders will be tracked down and slapped
with stinking trouts.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:14 +01:00
Thomas Gleixner 35e857cbeb genirq: Fixup core code namespace fallout
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:13 +01:00
Thomas Gleixner c78b9b65fa genirq: Implement generic irq_show_interrupts()
All archs implement show_interrupts() in more or less the same
way. That's tons of duplicated code with different bugs with no
value. Implement a generic version and deprecate show_interrupts()

Unfortunately we need some ifdeffery for !GENERIC_HARDIRQ archs.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:13 +01:00
Thomas Gleixner 1277a5325a genirq: Simplify handle_irq_event()
Now that all core users are converted one layer can go.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:13 +01:00
Thomas Gleixner 0877d66257 genirq: Use handle_irq_event() in the spurious poll code
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:13 +01:00
Thomas Gleixner 849f061c25 genirq: Use handle_perpcu_event() in handle_percpu_irq()
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:12 +01:00
Thomas Gleixner a60a5dc2db genirq: Use handle_irq_event() in handle_edge_irq()
It's safe to drop the IRQ_INPROGRESS flag between action chain walks
as we are protected by desc->lock.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:12 +01:00
Thomas Gleixner a7ae4de5c8 genirq: Use handle_irq_event() in handle_fasteoi_irq()
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:12 +01:00
Thomas Gleixner 1529866c63 genirq: Use handle_irq_event() in handle_level_irq()
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:12 +01:00
Thomas Gleixner 107781e721 genirq: Use handle_irq_event() in handle_simple_irq()
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:11 +01:00
Thomas Gleixner 4912609f22 genirq: Implement handle_irq_event()
Core code replacement for the ugly camel case. It contains all the
code which is shared in all handlers.

     clear status flags
     set INPROGRESS flag
     unlock
     call action chain
     note_interrupt
     lock
     clr INPROGRESS flag

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:11 +01:00
Thomas Gleixner d78f8dd36b genirq: Do not fiddle with IRQ_MASKED in handle_edge_irq()
IRQ_MASKED is set in mask_ack_irq() anyway. Remove it from
handle_edge_irq() to allow simpler ab^HHreuse of that function.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20110202212551.918484270@linutronix.de>
2011-02-19 12:58:11 +01:00
Thomas Gleixner 3aae994fb0 genirq: Consolidate IRQ_DISABLED
Handle IRQ_DISABLED consistent.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:11 +01:00
Thomas Gleixner 50f7c03275 genirq: Remove default magic
Now that everything uses the wrappers, we can remove the default
functions. None of those functions is performance critical.

That makes the IRQ_MASKED flag tracking fully consistent.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:10 +01:00
Thomas Gleixner 87923470c7 genirq: Consolidate disable/enable
Create irq_disable/enable and use them to keep the flags consistent.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:10 +01:00
Thomas Gleixner 4699923861 genirq: Consolidate startup/shutdown of interrupts
Aside of duplicated code some of the startup/shutdown sites do not
handle the MASKED/DISABLED flags and the depth field at all. Move that
to a helper function and take care of it there.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20110202212551.787481468@linutronix.de>
2011-02-19 12:58:10 +01:00
Thomas Gleixner 3b56f0585f genirq: Remove bogus conditional
The if (chip->irq_shutdown) check will always evaluate to true, as we
fill in chip->irq_shutdown with default_shutdown in
irq_chip_set_defaults() if the chip does not provide its own function.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20110202212551.667607458@linutronix.de>
2011-02-19 12:58:10 +01:00
Thomas Gleixner 1535dfacbf genirq: Move irq thread flags to core
Soleley used in core code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:09 +01:00
Thomas Gleixner fe200ae48e genirq: Mark polled irqs and defer the real handler
With the chip.end() function gone we might run into a situation where
a poll call runs and the real interrupt comes in, sees IRQ_INPROGRESS
and disables the line. That might be a perfect working one, which will
then be masked forever.

So mark them polled while the poll runs. When the real handler sees
IRQ_INPROGRESS it checks the poll flag and waits for the polling to
complete. Add the necessary amount of sanity checks to it to avoid
deadlocks.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:09 +01:00
Thomas Gleixner d05c65fff0 genirq: spurious: Run only one poller at a time
No point in running concurrent pollers which confuse each other by
setting PENDING.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:09 +01:00
Thomas Gleixner c7259cd7af genirq: Do not poll disabled, percpu and timer interrupts
There is no point in polling disabled lines.

percpu does not make sense at all because we only poll on the cpu
we're currently running on. Also polling per_cpu interrupts is racy as
hell. The handler runs without locking so we might get a huge
surprise.

If the timer interrupt needs polling, then we wont get there anyway.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:09 +01:00
Thomas Gleixner fa27271bc8 genirq: Fixup poll handling
try_one_irq() contains redundant code and lots of useless checks for
shared interrupts. Check for shared before setting IRQ_INPROGRESS and
then call handle_IRQ_event() while pending. Shorter version with the
same functionality.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:08 +01:00
Thomas Gleixner b738a50a20 genirq: Warn when handler enables interrupts
We run all handlers with interrupts disabled and expect them not to
enable them. Warn when we catch one who does.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:08 +01:00
Thomas Gleixner 1082687e8d genirq: Plug race in report_bad_irq()
We cannot walk the action chain unlocked. Even if IRQ_INPROGRESS is
set an action can be removed and we follow a null pointer. It's safe
to take the lock there, because the code which removes the action will
call synchronize_irq() which waits unlocked for IRQ_INPROGRESS going
away.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:08 +01:00
Thomas Gleixner 2b879eaf09 genirq: Remove redundant thread affinity setting
Thread affinity is already set by setup_affinity().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:08 +01:00
Thomas Gleixner 3b8249e759 genirq: Do not copy affinity before set
While rumaging through arch code I found that there are a few
workarounds which deal with the fact that the initial affinity setting
from request_irq() copies the mask into irq_data->affinity before the
chip code is called. In the normal path we unconditionally copy the
mask when the chip code returns 0.

Copy after the code is called and add a return code
IRQ_SET_MASK_OK_NOCOPY for the chip functions, which prevents the
copy. That way we see the real mask when the chip function decided to
truncate it further as some arches do. IRQ_SET_MASK_OK is 0, which is
the current behaviour.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:07 +01:00
Thomas Gleixner 569bda8df1 genirq: Always apply cpu online mask
If the affinity had been set by the user, then a later request_irq()
will honour that setting. But online cpus can have changed. So apply
the online mask and for this case as well.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:07 +01:00
Thomas Gleixner b008207cbd genirq: Rremove redundant check
IRQ_NO_BALANCING is already checked in irq_can_set_affinity() above,
no need to check it again.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:07 +01:00
Thomas Gleixner 1fa46f1f07 genirq: Simplify affinity related code
There is lot of #ifdef CONFIG_GENERIC_PENDING_IRQ along with
duplicated code in the irq core. Move the #ifdeffery into one place
and cleanup the code so it's readable. No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:07 +01:00
Thomas Gleixner a0cd9ca2b9 genirq: Namespace cleanup
The irq namespace has become quite convoluted. My bad.  Clean it up
and deprecate the old functions. All new functions follow the scheme:

irq number based:
    irq_set/get/xxx/_xxx(unsigned int irq, ...)

irq_data based:
	 irq_data_set/get/xxx/_xxx(struct irq_data *d, ....)

irq_desc based:
	 irq_desc_get_xxx(struct irq_desc *desc)

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:06 +01:00
Thomas Gleixner 43abe43ce0 genirq: Add missing buslock to set_irq_type(), set_irq_wake()
chips behind a slow bus cannot update the chip under desc->lock, but
we miss the chip_buslock/chip_bus_sync_unlock() calls around the set
type and set wake functions.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:06 +01:00
Thomas Gleixner e7bcecb7b1 genirq: Make nr_irqs runtime expandable
We face more and more the requirement to expand nr_irqs at
runtime. The reason are irq expanders which can not be detected in the
early boot stage. So we speculate nr_irqs to have enough room. Further
Xen needs extra irq numbers and we really want to avoid adding more
"detection" code into the early boot. There is no real good reason why
we need to limit nr_irqs at early boot.

Allow the allocation code to expand nr_irqs. We have already 8k extra
number space in the allocation bitmap, so lets use it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:58:06 +01:00
Thomas Gleixner 218502bfe6 Merge branch 'irq/urgent' into irq/core
Reason: Further patches are conflicting with mainline fixes

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-19 12:56:43 +01:00
Thomas Gleixner 6d83f94db9 genirq: Disable the SHIRQ_DEBUG call in request_threaded_irq for now
With CONFIG_SHIRQ_DEBUG=y we call a newly installed interrupt handler
in request_threaded_irq().

The original implementation (commit a304e1b8) called the handler
_BEFORE_ it was installed, but that caused problems with handlers
calling disable_irq_nosync(). See commit 377bf1e4.

It's braindead in the first place to call disable_irq_nosync in shared
handlers, but ....

Moving this call after we installed the handler looks innocent, but it
is very subtle broken on SMP.

Interrupt handlers rely on the fact, that the irq core prevents
reentrancy.

Now this debug call violates that promise because we run the handler
w/o the IRQ_INPROGRESS protection - which we cannot apply here because
that would result in a possibly forever masked interrupt line.

A concurrent real hardware interrupt on a different CPU results in
handler reentrancy and can lead to complete wreckage, which was
unfortunately observed in reality and took a fricking long time to
debug.

Leave the code here for now. We want this debug feature, but that's
not easy to fix. We really should get rid of those
disable_irq_nosync() abusers and remove that function completely.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: stable@kernel.org # .28 -> .37
2011-02-19 12:11:13 +01:00
Thomas Gleixner c1ee626428 genirq: Prevent access beyond allocated_irqs bitmap
Lars-Peter Clausen pointed out:

   I stumbled upon this while looking through the existing archs using
   SPARSE_IRQ.  Even with SPARSE_IRQ the NR_IRQS is still the upper
   limit for the number of IRQs.

   Both PXA and MMP set NR_IRQS to IRQ_BOARD_START, with
   IRQ_BOARD_START being the number of IRQs used by the core.

   In various machine files the nr_irqs field of the ARM machine
   defintion struct is then set to "IRQ_BOARD_START + NR_BOARD_IRQS".

   As a result "nr_irqs" will greater then NR_IRQS which then again
   causes the "allocated_irqs" bitmap in the core irq code to be
   accessed beyond its size overwriting unrelated data.

The core code really misses a sanity check there.

This went unnoticed so far as by chance the compiler/linker places
data behind that bitmap which gets initialized later on those affected
platforms.

So the obvious fix would be to add a sanity check in early_irq_init()
and break all affected platforms. Though that check wants to be
backported to stable as well, which will require to fix all known
problematic platforms and probably some more yet not known ones as
well. Lots of churn.

A way simpler solution is to allocate a slightly larger bitmap and
avoid the whole churn w/o breaking anything. Add a few warnings when
an arch returns utter crap.

Reported-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org # .37
Cc: Haojian Zhuang <haojian.zhuang@marvell.com>
Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
2011-02-19 12:10:51 +01:00
Thomas Gleixner 51327ada71 Merge branch 'irq/for-mips' into irq/core
Reason: irq/for-mips is provided for mips to make core independent
        progress. Merge it into irq/core to avoid conflicts

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-11 00:27:03 +01:00
David Daney 986c011ddb genirq: Call bus_lock/unlock functions in setup_irq()
irq_chips that supply .irq_bus_lock/.irq_bus_sync_unlock functions,
expect that the other chip methods will be called inside of calls to
the pair.  If this expectation is not met, things tend to not work.

Make setup_irq() call chip_bus_lock()/chip_bus_sync_unlock() too.

For the vast majority of irq_chips, this will be a NOP as most don't
have these bus lock functions.

[ tglx: No we don't want to call that in __setup_irq(). Way too many
  	error exit pathes. ]

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
LKML-Reference: <1297296265-18680-1-git-send-email-ddaney@caviumnetworks.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-11 00:25:13 +01:00
Thomas Gleixner 44951a60ff genirq: Remove dead code
CONFIG_KSTAT_IRQS_ONDEMAND does not exist. It's not worth to implement
it. Use sparse irqs if you care about memory consumption of the
interrupt layer.

Found by undertaker: http://vamos.informatik.uni-erlangen.de/trac/undertaker

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-08 19:37:13 +01:00
Thomas Gleixner c9a443cdf7 Merge branch 'irq/for-xen' into irq/core
irq/for-xen contains new functionality to avoid Xen private irq
hackery. That branch has a single irq commit and is pulled by Xen to
base their new features on.

Merge it into irq/core as other patches modify the same code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-08 16:38:21 +01:00
Thomas Gleixner dc5f219e88 genirq: Add IRQF_FORCE_RESUME
Xen needs to reenable interrupts which are marked IRQF_NO_SUSPEND in the
resume path. Add a flag to force the reenabling in the resume code.

Tested-and-acked-by: Ian Campbell <Ian.Campbell@eu.citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-08 16:36:47 +01:00
Thomas Gleixner 285c1a2c3a Merge branch 'irq/urgent' into irq/core
Reason: Get mainline fixes integrated. Further patches conflict with
        them

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-02-05 21:50:05 +01:00
Thomas Gleixner f1a06390d0 genirq: Prevent irq storm on migration
move_native_irq() masks and unmasks the interrupt line
unconditionally, but the interrupt line might be masked due to a
threaded oneshot handler in progress. Unmasking the line in that case
can lead to interrupt storms. Observed on PREEMPT_RT.

Originally-from: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org
2011-02-02 22:15:08 +01:00
Thomas Gleixner 1fb0ef31f4 genirq: Fix affinity notifier fallout
The new code of commit cd7eab44e(genirq: Add IRQ affinity notifiers)
references irq_desc.affinity which fails to compile with
CONFIG_GENERIC_HARDIRQS_NO_DEPRECATED=y.

Use irq_desc.irq_data.affinity instead.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ben Hutchings <bhutchings@solarflare.com>
2011-01-31 08:57:41 +01:00
Ben Hutchings cd7eab44e9 genirq: Add IRQ affinity notifiers
When initiating I/O on a multiqueue and multi-IRQ device, we may want
to select a queue for which the response will be handled on the same
or a nearby CPU.  This requires a reverse-map of IRQ affinity.  Add a
notification mechanism to support this.

This is based closely on work by Thomas Gleixner <tglx@linutronix.de>.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Cc: linux-net-drivers@solarflare.com
Cc: Tom Herbert <therbert@google.com>
Cc: David Miller <davem@davemloft.net>
LKML-Reference: <1295470904.11126.84.camel@bwh-desktop>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-01-22 17:34:25 +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
Eric Dumazet 6c9ae009b2 irq: use per_cpu kstat_irqs
Use modern per_cpu API to increment {soft|hard}irq counters, and use
per_cpu allocation for (struct irq_desc)->kstats_irq instead of an array.

This gives better SMP/NUMA locality and saves few instructions per irq.

With small nr_cpuids values (8 for example), kstats_irq was a small array
(less than L1_CACHE_BYTES), potentially source of false sharing.

In the !CONFIG_SPARSE_IRQ case, remove the huge, NUMA/cache unfriendly
kstat_irqs_all[NR_IRQS][NR_CPUS] array.

Note: we still populate kstats_irq for all possible irqs in
early_irq_init().  We probably could use on-demand allocations.  (Code
included in alloc_descs()).  Problem is not all IRQS are used with a prior
alloc_descs() call.

kstat_irqs_this_cpu() is not used anymore, remove it.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Reviewed-by: Christoph Lameter <cl@linux.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:31 -08:00
Peter Zijlstra c9b5f501ef sched: Constify function scope static struct sched_param usage
Function-scope statics are discouraged because they are
easily overlooked and can cause subtle bugs/races due to
their global (non-SMP safe) nature.

Linus noticed that we did this for sched_param - at minimum
make the const.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: Message-ID: <AANLkTinotRxScOHEb0HgFgSpGPkq_6jKTv5CfvnQM=ee@mail.gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-01-07 15:55:45 +01:00
Ingo Molnar 8e9255e6a2 Merge branch 'linus' into sched/core
Merge reason: we want to queue up dependent cleanup

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-12-08 20:15:29 +01:00
Kenji Kaneshige 25c9170ed6 genirq: Fix incorrect proc spurious output
Since commit a1afb637(switch /proc/irq/*/spurious to seq_file) all
/proc/irq/XX/spurious files show the information of irq 0.

Current irq_spurious_proc_open() passes on NULL as the 3rd argument,
which is used as an IRQ number in irq_spurious_proc_show(), to the
single_open(). Because of this, all the /proc/irq/XX/spurious file
shows IRQ 0 information regardless of the IRQ number.

To fix the problem, irq_spurious_proc_open() must pass on the
appropreate data (IRQ number) to single_open().

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Reviewed-by: Yong Zhang <yong.zhang0@gmail.com>
LKML-Reference: <4CF4B778.90604@jp.fujitsu.com>
Cc: stable@kernel.org [2.6.33+]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-12-01 08:44:26 +01:00
Ingo Molnar 92fd4d4d67 Merge commit 'v2.6.37-rc2' into sched/core
Merge reason: Move to a .37-rc base.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-11-18 13:22:26 +01:00
Linus Torvalds 82279e6bd7 Merge branches 'irq-core-for-linus' and 'core-locking-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:
  genirq: Fix up irq_node() for irq_data changes.
  genirq: Add single IRQ reservation helper
  genirq: Warn if enable_irq is called before irq is set up

* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  semaphore: Remove mutex emulation
  staging: Final semaphore cleanup
  jbd2: Convert jbd2_slab_create_sem to mutex
  hpfs: Convert sbi->hpfs_creation_de to mutex

Fix up trivial change/delete conflicts with deleted 'dream' drivers
(drivers/staging/dream/camera/{mt9d112.c,mt9p012_fox.c,mt9t013.c,s5k3e2fx.c})
2010-10-31 20:40:24 -04:00
KAMEZAWA Hiroyuki 478735e388 /proc/stat: fix scalability of irq sum of all cpu
In /proc/stat, the number of per-IRQ event is shown by making a sum each
irq's events on all cpus.  But we can make use of kstat_irqs().

kstat_irqs() do the same calculation, If !CONFIG_GENERIC_HARDIRQ,
it's not a big cost. (Both of the number of cpus and irqs are small.)

If a system is very big and CONFIG_GENERIC_HARDIRQ, it does

	for_each_irq()
		for_each_cpu()
			- look up a radix tree
			- read desc->irq_stat[cpu]
This seems not efficient. This patch adds kstat_irqs() for
CONFIG_GENRIC_HARDIRQ and change the calculation as

	for_each_irq()
		look up radix tree
		for_each_cpu()
			- read desc->irq_stat[cpu]

This reduces cost.

A test on (4096cpusp, 256 nodes, 4592 irqs) host (by Jack Steiner)

%time cat /proc/stat > /dev/null

Before Patch:	 2.459 sec
After Patch :	  .561 sec

[akpm@linux-foundation.org: unexport kstat_irqs, coding-style tweaks]
[akpm@linux-foundation.org: fix unused variable 'per_irq_sum']
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tested-by: Jack Steiner <steiner@sgi.com>
Acked-by: Jack Steiner <steiner@sgi.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-27 18:03:13 -07:00
KOSAKI Motohiro fe7de49f9d sched: Make sched_param argument static in sched_setscheduler() callers
Andrew Morton pointed out almost all sched_setscheduler() callers are
using fixed parameters and can be converted to static.  It reduces runtime
memory use a little.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: James Morris <jmorris@namei.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-10-23 17:56:48 +02:00
Thomas Gleixner 2656c36699 genirq: Warn if enable_irq is called before irq is set up
The recent changes in the genirq core unearthed a bug in arch/um which
called enable_irq() before the interrupt was set up.

Warn and return instead of crashing the machine with a NULL pointer
dereference.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Weinberger <richard@nod.at>
2010-10-22 16:10:29 +02:00
Thomas Gleixner c0a19ebc01 genirq: Fix CONFIG_GENIRQ_NO_DEPRECATED=y build
This option can be set to verify the full conversion to the new chip
functions. Fix the fallout of the patch rework, so the core code
compiles and works with it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-10-12 21:59:55 +02:00
Thomas Gleixner baa0d233af genirq: Switch sparse_irq allocator to GFP_KERNEL
The allocator functions are now called outside of preempt disabled
regions. Switch to GFP_KERNEL.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-12 16:53:45 +02:00
Thomas Gleixner a05a900a51 genirq: Make sparse_lock a mutex
No callers from atomic regions. 

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-12 16:53:45 +02:00
Thomas Gleixner 78f90d91f3 genirq: Remove the now unused sparse irq leftovers
The move_irq_desc() function was only used due to the problem that the
allocator did not free the old descriptors. So the descriptors had to
be moved in create_irq_nr(). That's history.

The code would have never been able to move active interrupt
descriptors on affinity settings. That can be done in a completely
different way w/o all this horror.

Remove all of it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-12 16:53:44 +02:00
Thomas Gleixner b7b29338dc genirq: Sanitize dynamic irq handling
Use the cleanup functions of the dynamic allocator. No need to have
separate implementations.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-12 16:53:44 +02:00
Thomas Gleixner b7d0d8258a genirq: Remove arch_init_chip_data()
This function should have not been there in the first place.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-12 16:53:44 +02:00
Thomas Gleixner b683de2b3c genirq: Query arch for number of early descriptors
sparse irq sets up NR_IRQS_LEGACY irq descriptors and archs then go
ahead and allocate more.

Use the unused return value of arch_probe_nr_irqs() to let the
architecture return the number of early allocations. Fix up all users.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-12 16:39:08 +02:00
Thomas Gleixner aa99ec0f3f genirq: Use sane sparse allocator
Make irq_to_desc_alloc_node() a wrapper around the new allocator.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
2010-10-12 16:39:07 +02:00
Thomas Gleixner 06f6c3399e genirq: Implement irq reservation
Mark a range of interrupts as allocated. In the SPARSE_IRQ=n case we
need this to update the bitmap for the legacy irqs so the enumerator
via irq_get_next_irq() works.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-10-12 16:39:07 +02:00