Commit Graph

285 Commits

Author SHA1 Message Date
Pavel Emelianov f72fa70760 [PATCH] Fix misrouted interrupts deadlocks
While testing kernel on machine with "irqpoll" option I've caught such a
lockup:

	__do_IRQ()
	   spin_lock(&desc->lock);
           desc->chip->ack(); /* IRQ is ACKed */
	note_interrupt()
	misrouted_irq()
	handle_IRQ_event()
           if (...)
	      local_irq_enable_in_hardirq();
	/* interrupts are enabled from now */
	...
	__do_IRQ() /* same IRQ we've started from */
	   spin_lock(&desc->lock); /* LOCKUP */

Looking at misrouted_irq() code I've found that a potential deadlock like
this can also take place:

1CPU:
__do_IRQ()
   spin_lock(&desc->lock); /* irq = A */
misrouted_irq()
   for (i = 1; i < NR_IRQS; i++) {
      spin_lock(&desc->lock); /* irq = B */
      if (desc->status & IRQ_INPROGRESS) {

2CPU:
__do_IRQ()
   spin_lock(&desc->lock); /* irq = B */
misrouted_irq()
   for (i = 1; i < NR_IRQS; i++) {
      spin_lock(&desc->lock); /* irq = A */
      if (desc->status & IRQ_INPROGRESS) {

As the second lock on both CPUs is taken before checking that this irq is
being handled in another processor this may cause a deadlock.  This issue
is only theoretical.

I propose the attached patch to fix booth problems: when trying to handle
misrouted IRQ active desc->lock may be unlocked.

Acked-by: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-13 07:40:43 -08:00
Ingo Molnar a460e745e8 [PATCH] genirq: clean up irq-flow-type naming
Introduce desc->name and eliminate the handle_irq_name() hack.  Add
set_irq_chip_and_handler_name() to set the flow type and name at once.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Matthew Wilcox <willy@debian.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-17 08:18:45 -07:00
Reinette Chatre 01a3ee2b20 [PATCH] bitmap: parse input from kernel and user buffers
lib/bitmap.c:bitmap_parse() is a library function that received as input a
user buffer.  This seemed to have originated from the way the write_proc
function of the /proc filesystem operates.

This has been reworked to not use kmalloc and eliminates a lot of
get_user() overhead by performing one access_ok before using __get_user().

We need to test if we are in kernel or user space (is_user) and access the
buffer differently.  We cannot use __get_user() to access kernel addresses
in all cases, for example in architectures with separate address space for
kernel and user.

This function will be useful for other uses as well; for example, taking
input for /sysfs instead of /proc, so it was changed to accept kernel
buffers.  We have this use for the Linux UWB project, as part as the
upcoming bandwidth allocator code.

Only a few routines used this function and they were changed too.

Signed-off-by: Reinette Chatre <reinette.chatre@linux.intel.com>
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Joe Korty <joe.korty@ccur.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-11 11:14:22 -07:00
Frederik Deweerdt e317c8ccaa [PATCH] ixp4xxdefconfig arm fixes
With the following patch, the ixp4xxdefconfig builds correctly.  I'll
test some more configs if I get some time.

Signed-off-by: Frederik Deweerdt <frederik.deweerdt@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-06 12:11:08 -07:00
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
David Howells da482792a6 IRQ: Typedef the IRQ handler function type
Typedef the IRQ handler function type.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1356d1e5fd256997e3d3dce0777ab787d0515c7a commit)
2006-10-05 13:28:27 +01:00
David Howells 57a58a9435 IRQ: Typedef the IRQ flow handler function type
Typedef the IRQ flow handler function type.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 8e973fbdf5716b93a0a8c0365be33a31ca0fa351 commit)
2006-10-05 13:28:06 +01:00
Eric W. Biederman 1f80025e62 [PATCH] msi: simplify msi sanity checks by adding with generic irq code
Currently msi.c is doing sanity checks that make certain before an irq is
destroyed it has no more users.

By adding irq_has_action I can perform the test is a generic way, instead of
relying on a msi specific data structure.

By performing the core check in dynamic_irq_cleanup I ensure every user of
dynamic irqs has a test present and we don't free resources that are in use.

In msi.c this allows me to kill the attrib.state member of msi_desc and all of
the assciated code to maintain it.

To keep from freeing data structures when irq cleanup code is called to soon
changing dyanamic_irq_cleanup is insufficient because there are msi specific
data structures that are also not safe to free.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg KH <greg@kroah.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 07:55:29 -07:00
Eric W. Biederman 3a16d71362 [PATCH] genirq: irq: add a dynamic irq creation API
With the msi support comes a new concept in irq handling, irqs that are
created dynamically at run time.

Currently the msi code allocates irqs backwards.  First it allocates a
platform dependent routing value for an interrupt the ``vector'' and then it
figures out from the vector which irq you are on.

This msi backwards allocator suffers from two basic problems.  The allocator
suffers because it is trying to do something that is architecture specific in
a generic way making it brittle, inflexible, and tied to tightly to the
architecture implementation.  The alloctor also suffers from it's very
backwards nature as it has tied things together that should have no
dependencies.

To solve the basic dynamic irq allocation problem two new architecture
specific functions are added: create_irq and destroy_irq.

create_irq takes no input and returns an unused irq number, that won't be
reused until it is returned to the free poll with destroy_irq.  The irq then
can be used for any purpose although the only initial consumer is the msi
code.

destroy_irq takes an irq number allocated with create_irq and returns it to
the free pool.

Making this functionality per architecture increases the simplicity of the irq
allocation code and increases it's flexibility.

dynamic_irq_init() and dynamic_irq_cleanup() are added to automate the
irq_desc initializtion that should happen for dynamic irqs.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 07:55:27 -07:00
Eric W. Biederman e7b946e98a [PATCH] genirq: irq: add moved_masked_irq
Currently move_native_irq disables and renables the irq we are migrating to
ensure we don't take that irq when we are actually doing the migration
operation.  Disabling the irq needs to happen but sometimes doing the work is
move_native_irq is too late.

On x86 with ioapics the irq move sequences needs to be:
edge_triggered:
  mask irq.
  move irq.
  unmask irq.
  ack irq.
level_triggered:
  mask irq.
  ack irq.
  move irq.
  unmask irq.

We can easily perform the edge triggered sequence, with the current defintion
of move_native_irq.  However the level triggered case does not map well.  For
that I have added move_masked_irq, to allow me to disable the irqs around both
the ack and the move.

Q: Why have we not seen this problem earlier?

A: The only symptom I have been able to reproduce is that if we change
   the vector before acknowleding an irq the wrong irq is acknowledged.
   Since we currently are not reprogramming the irq vector during
   migration no problems show up.

   We have to mask the irq before we acknowledge the irq or else we could
   hit a window where an irq is asserted just before we acknowledge it.

   Edge triggered irqs do not have this problem because acknowledgements
   do not propogate in the same way.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 07:55:26 -07:00
Eric W. Biederman a24ceab4f4 [PATCH] genirq: irq: convert the move_irq flag from a 32bit word to a single bit
The primary aim of this patchset is to remove maintenances problems caused by
the irq infrastructure.  The two big issues I address are an artificially
small cap on the number of irqs, and that MSI assumes vector == irq.  My
primary focus is on x86_64 but I have touched other architectures where
necessary to keep them from breaking.

- To increase the number of irqs I modify the code to look at the (cpu,
  vector) pair instead of just looking at the vector.

  With a large number of irqs available systems with a large irq count no
  longer need to compress their irq numbers to fit.  Removing a lot of brittle
  special cases.

  For acpi guys the result is that irq == gsi.

- Addressing the fact that MSI assumes irq == vector takes a few more
  patches.  But suffice it to say when I am done none of the generic irq code
  even knows what a vector is.

In quick testing on a large Unisys x86_64 machine we stumbled over at least
one driver that assumed that NR_IRQS could always fit into an 8 bit number.
This driver is clearly buggy today.  But this has become a class of bugs that
it is now much easier to hit.

This patch:

This is a minor space optimization.  In practice I don't think this has any
affect because of our alignment constraints and the other fields but there is
not point in chewing up an uncessary word and since we already read the flag
field this should improve the cache hit ratio of the irq handler.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 07:55:26 -07:00
Yoichi Yuasa 538d9d532b [PATCH] irq: remove a extra line
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:07 -07:00
Yoichi Yuasa 2ff6fd8f4a [PATCH] irq: fixed coding style
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:07 -07:00
David Howells af8c65b57a [PATCH] FRV: permit __do_IRQ() to be dispensed with
Permit __do_IRQ() to be dispensed with based on a configuration option.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:53 -07:00
Ingo Molnar 86998aa653 [PATCH] genirq core: fix handle_level_irq()
while porting the -rt tree to 2.6.18-rc7 i noticed the following
screaming-IRQ scenario on an SMP system:

 2274  0Dn.:1 0.001ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.010ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.020ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.029ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.039ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.048ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.058ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.068ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.077ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.087ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)
 2274  0Dn.:1 0.097ms: do_IRQ+0xc/0x103  <= (ret_from_intr+0x0/0xf)

as it turns out, the bug is caused by handle_level_irq(), which if it
races with another CPU already handling this IRQ, it _unmasks_ the IRQ
line on the way out. This is not how 2.6.17 works, and we introduced
this bug in one of the early genirq cleanups right before it went into
-mm. (the bug was not in the genirq patchset for a long time, and we
didnt notice the bug due to the lack of -rt rebase to the new genirq
code. -rt, and hardirq-preemption in particular opens up such races much
wider than anything else.)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-19 07:57:20 -07:00
Imre Deak e1ed7ac77b [PATCH] genirq: fix typo in IRQ resend
Fix a bug where the IRQ_PENDING flag is never cleared and the ISR is called
endlessly without an actual interrupt.

Signed-off-by: Imre Deak <imre.deak@solidboot.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-16 12:54:30 -07:00
Henrik Kretzschmar 43a1dd502f [PATCH] kerneldoc for handle_bad_irq()
Adds the description of the parameters from handle_bad_irq().

Signed-off-by: Henrik Kretzschmar <henne@nachtwindheim.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-01 11:39:09 -07:00
David Brownell 15a647eba9 [PATCH] genirq: {en,dis}able_irq_wake() need refcounting too
IRQs need refcounting and a state flag to track whether the the IRQ should
be enabled or disabled as a "normal IRQ" source after a series of calls to
{en,dis}able_irq().  For shared IRQs, the IRQ must be enabled so long as at
least one driver needs it active.

Likewise, IRQs need the same support to track whether the IRQ should be
enabled or disabled as a "wakeup event" source after a series of calls to
{en,dis}able_irq_wake().  For shared IRQs, the IRQ must be enabled as a
wakeup source during sleep so long as at least one driver needs it.  But
right now they _don't have_ that refcounting ...  which means sharing a
wakeup-capable IRQ can't work correctly in some configurations.

This patch adds the refcount and flag mechanisms to set_irq_wake() -- which
is what {en,dis}able_irq_wake() call -- and minimal documentation of what
the irq wake mechanism does.

Drivers relying on the older (broken) "toggle" semantics will trigger a
warning; that'll be a handful of drivers on ARM systems.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-31 13:28:36 -07:00
Linus Torvalds 912b2539e1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
* git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
  powerpc: add defconfig for Freescale MPC8349E-mITX board
  powerpc: Add base support for the Freescale MPC8349E-mITX eval board
  Documentation: correct values in MPC8548E SEC example node
  [POWERPC] Actually copy over i8259.c to arch/ppc/syslib this time
  [POWERPC] Add new interrupt mapping core and change platforms to use it
  [POWERPC] Copy i8259 code back to arch/ppc
  [POWERPC] New device-tree interrupt parsing code
  [POWERPC] Use the genirq framework
  [PATCH] genirq: Allow fasteoi handler to retrigger disabled interrupts
  [POWERPC] Update the SWIM3 (powermac) floppy driver
  [POWERPC] Fix error handling in detecting legacy serial ports
  [POWERPC] Fix booting on Momentum "Apache" board (a Maple derivative)
  [POWERPC] Fix various offb and BootX-related issues
  [POWERPC] Add a default config for 32-bit CHRP machines
  [POWERPC] fix implicit declaration on cell.
  [POWERPC] change get_property to return void *
2006-07-03 15:28:34 -07:00
Ingo Molnar 366c7f554e [PATCH] lockdep: annotate enable_in_hardirq()
Make use of local_irq_enable_in_hardirq() API to annotate places that enable
hardirqs in hardirq context.

Has no effect on non-lockdep kernels.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:09 -07:00
Ingo Molnar 243c7621aa [PATCH] lockdep: annotate genirq
Teach special (recursive) locking code to the lock validator.  Has no effect
on non-lockdep kernels.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:06 -07:00
Ingo Molnar fbb9ce9530 [PATCH] lockdep: core
Do 'make oldconfig' and accept all the defaults for new config options -
reboot into the kernel and if everything goes well it should boot up fine and
you should have /proc/lockdep and /proc/lockdep_stats files.

Typically if the lock validator finds some problem it will print out
voluminous debug output that begins with "BUG: ..." and which syslog output
can be used by kernel developers to figure out the precise locking scenario.

What does the lock validator do?  It "observes" and maps all locking rules as
they occur dynamically (as triggered by the kernel's natural use of spinlocks,
rwlocks, mutexes and rwsems).  Whenever the lock validator subsystem detects a
new locking scenario, it validates this new rule against the existing set of
rules.  If this new rule is consistent with the existing set of rules then the
new rule is added transparently and the kernel continues as normal.  If the
new rule could create a deadlock scenario then this condition is printed out.

When determining validity of locking, all possible "deadlock scenarios" are
considered: assuming arbitrary number of CPUs, arbitrary irq context and task
context constellations, running arbitrary combinations of all the existing
locking scenarios.  In a typical system this means millions of separate
scenarios.  This is why we call it a "locking correctness" validator - for all
rules that are observed the lock validator proves it with mathematical
certainty that a deadlock could not occur (assuming that the lock validator
implementation itself is correct and its internal data structures are not
corrupted by some other kernel subsystem).  [see more details and conditionals
of this statement in include/linux/lockdep.h and
Documentation/lockdep-design.txt]

Furthermore, this "all possible scenarios" property of the validator also
enables the finding of complex, highly unlikely multi-CPU multi-context races
via single single-context rules, increasing the likelyhood of finding bugs
drastically.  In practical terms: the lock validator already found a bug in
the upstream kernel that could only occur on systems with 3 or more CPUs, and
which needed 3 very unlikely code sequences to occur at once on the 3 CPUs.
That bug was found and reported on a single-CPU system (!).  So in essence a
race will be found "piecemail-wise", triggering all the necessary components
for the race, without having to reproduce the race scenario itself!  In its
short existence the lock validator found and reported many bugs before they
actually caused a real deadlock.

To further increase the efficiency of the validator, the mapping is not per
"lock instance", but per "lock-class".  For example, all struct inode objects
in the kernel have inode->inotify_mutex.  If there are 10,000 inodes cached,
then there are 10,000 lock objects.  But ->inotify_mutex is a single "lock
type", and all locking activities that occur against ->inotify_mutex are
"unified" into this single lock-class.  The advantage of the lock-class
approach is that all historical ->inotify_mutex uses are mapped into a single
(and as narrow as possible) set of locking rules - regardless of how many
different tasks or inode structures it took to build this set of rules.  The
set of rules persist during the lifetime of the kernel.

To see the rough magnitude of checking that the lock validator does, here's a
portion of /proc/lockdep_stats, fresh after bootup:

 lock-classes:                            694 [max: 2048]
 direct dependencies:                  1598 [max: 8192]
 indirect dependencies:               17896
 all direct dependencies:             16206
 dependency chains:                    1910 [max: 8192]
 in-hardirq chains:                      17
 in-softirq chains:                     105
 in-process chains:                    1065
 stack-trace entries:                 38761 [max: 131072]
 combined max dependencies:         2033928
 hardirq-safe locks:                     24
 hardirq-unsafe locks:                  176
 softirq-safe locks:                     53
 softirq-unsafe locks:                  137
 irq-safe locks:                         59
 irq-unsafe locks:                      176

The lock validator has observed 1598 actual single-thread locking patterns,
and has validated all possible 2033928 distinct locking scenarios.

More details about the design of the lock validator can be found in
Documentation/lockdep-design.txt, which can also found at:

   http://redhat.com/~mingo/lockdep-patches/lockdep-design.txt

[bunk@stusta.de: cleanups]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:03 -07:00
Benjamin Herrenschmidt 5a43a066b1 [PATCH] genirq: Allow fasteoi handler to retrigger disabled interrupts
Make the fasteoi handler mark disabled interrupts as pending if they
happen anyway. This allow implementation of a delayed disable scheme
with the fasteoi handler.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-07-03 19:54:59 +10:00
Thomas Gleixner 284c66806e [PATCH] genirq:fixup missing SA_PERCPU replacement
The irqflags consolidation converted SA_PERCPU_IRQ to IRQF_PERCPU but
did not define the new constant.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-02 17:29:22 -07:00
Thomas Gleixner d061daa0e3 [PATCH] genirq: ARM dyntick cleanup
Linus: "The hacks in kernel/irq/handle.c are really horrid. REALLY
horrid."

They are indeed. Move the dyntick quirks to ARM where they belong.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-02 17:29:21 -07:00
Linus Torvalds b4b9034132 Merge branch 'genirq' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'genirq' of master.kernel.org:/home/rmk/linux-2.6-arm: (24 commits)
  [ARM] 3683/2:  ARM: Convert at91rm9200 to generic irq handling
  [ARM] 3682/2:  ARM: Convert ixp4xx to generic irq handling
  [ARM] 3702/1: ARM: Convert ixp23xx to generic irq handling
  [ARM] 3701/1: ARM: Convert plat-omap to generic irq handling
  [ARM] 3700/1: ARM: Convert lh7a40x to generic irq handling
  [ARM] 3699/1: ARM: Convert s3c2410 to generic irq handling
  [ARM] 3698/1: ARM: Convert sa1100 to generic irq handling
  [ARM] 3697/1: ARM: Convert shark to generic irq handling
  [ARM] 3696/1: ARM: Convert clps711x to generic irq handling
  [ARM] 3694/1: ARM: Convert ecard driver to generic irq handling
  [ARM] 3693/1: ARM: Convert omap1 to generic irq handling
  [ARM] 3691/1: ARM: Convert imx to generic irq handling
  [ARM] 3688/1: ARM: Convert clps7500 to generic irq handling
  [ARM] 3687/1: ARM: Convert integrator to generic irq handling
  [ARM] 3685/1: ARM: Convert pxa to generic irq handling
  [ARM] 3684/1: ARM: Convert l7200 to generic irq handling
  [ARM] 3681/1: ARM: Convert ixp2000 to generic irq handling
  [ARM] 3680/1: ARM: Convert footbridge to generic irq handling
  [ARM] 3695/1: ARM drivers/pcmcia: Fixup includes
  [ARM] 3689/1: ARM drivers/input/touchscreen: Fixup includes
  ...

Manual conflict resolved in kernel/irq/handle.c (butt-ugly ARM tickless
code).
2006-07-02 15:07:45 -07:00
Thomas Gleixner 3cca53b02a [PATCH] irq-flags: generic irq: Use the new IRQF_ constants
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-02 13:58:49 -07:00
Thomas Gleixner f8b5473fcb [ARM] 3690/1: genirq: Introduce and make use of dummy irq chip
Patch from Thomas Gleixner

From: Thomas Gleixner <tglx@linutronix.de>

ARM has a couple of really dumb interrupt controllers.
Implement a generic one and fixup the ARM migration. ARM reused
the no_irq_chip for this purpose, but this does not work out
for platforms which are not converted to the new interrupt
type handling model.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-07-01 22:30:08 +01:00
Thomas Gleixner a2166abd06 [ARM] 3679/1: ARM: Make ARM dyntick implementation work with genirq
Patch from Thomas Gleixner

From: Thomas Gleixner <tglx@linutronix.de>

Make the ARM dyntick implementation work with the generic
irq code. This hopefully goes away once we consolidated the
dyntick implementations.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-07-01 22:30:07 +01:00
Bjorn Helgaas e8c4b9d003 [PATCH] IRQ: warning message cleanup
Make warnings more consistent.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-01 09:55:57 -07:00
Bjorn Helgaas 17311c03c3 [PATCH] IRQ: Use SA_PERCPU_IRQ, not IRQ_PER_CPU, for irqaction.flags
IRQ_PER_CPU is a bit in the struct irq_desc "status" field, not in the
struct irqaction "flags", so the previous code checked the wrong bit.

SA_PERCPU_IRQ is only used by drivers/char/mmtimer.c for SGI ia64 boxes.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-01 09:55:57 -07:00
Jörn Engel 6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Ingo Molnar 47c2a3aa44 [PATCH] genirq: add chip->eoi(), fastack -> fasteoi
Clean up the fastack concept by turning it into fasteoi and introducing the
->eoi() method for chips.

This also allows the cleanup of an i386 EOI quirk - now the quirk is
cleanly separated from the pure ACK implementation.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:26 -07:00
Benjamin Herrenschmidt 98bb244b68 [PATCH] genirq: fasteoi handler: handle interrupt disabling
Note when a disable interrupt happened with the fasteoi handler as well so
that delayed disable can be implemented with fasteoi-type controllers.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:25 -07:00
Ingo Molnar 43f7775944 [PATCH] genirq: more verbose debugging on unexpected IRQ vectors
One frequent sign of IRQ handling bugs is the appearance of unexpected
vectors.  Print out all the IRQ state in that case.  We dont want this patch
upstream, but it is useful during initial testing.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:25 -07:00
Ingo Molnar f1c2662cbc [PATCH] genirq: cleanup: no_irq_type -> no_irq_chip rename
Rename no_irq_type to no_irq_chip.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:25 -07:00
Thomas Gleixner e76de9f8eb [PATCH] genirq: add SA_TRIGGER support
Enable drivers to request an IRQ with a given irq-flow (trigger/polarity)
setting.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:24 -07:00
Thomas Gleixner ba9a2331ba [PATCH] genirq: add irq-wake (power-management) support
Enable platforms to set the irq-wake (power-management) properties of an IRQ.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:24 -07:00
Ingo Molnar 7a55713ab4 [PATCH] genirq: add handle_bad_irq()
Handle bad IRQ vectors via the irqchip mechanism.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:24 -07:00
Thomas Gleixner dd87eb3a24 [PATCH] genirq: add irq-chip support
Enable platforms to use the irq-chip and irq-flow abstractions: allow setting
of the chip, the type and provide highlevel handlers for common irq-flows.

[rostedt@goodmis.org: misroute-irq: Don't call desc->chip->end because of edge interrupts]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:24 -07:00
Thomas Gleixner 6a6de9ef58 [PATCH] genirq: core
Core genirq support: add the irq-chip and irq-flow abstractions.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:24 -07:00
Ingo Molnar a34db9b28a [PATCH] genirq: update copyrights
Update/add copyrights in the generic IRQ code.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:24 -07:00
Thomas Gleixner 94d39e1f6e [PATCH] genirq: add IRQ_NOAUTOEN support
Enable platforms to disable the automatic enabling of freshly set up irqs.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:24 -07:00
Thomas Gleixner 6550c775cb [PATCH] genirq: add IRQ_NOREQUEST support
Enable platforms to disable request_irq() for certain interrupts.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:24 -07:00
Thomas Gleixner 3418d72404 [PATCH] genirq: add IRQ_NOPROBE support
Introduce IRQ_NOPROBE: enables platforms to control chip-probing.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:24 -07:00
Thomas Gleixner a4633adcdb [PATCH] genirq: add genirq sw IRQ-retrigger
Enable platforms that do not have a hardware-assisted hardirq-resend mechanism
to resend them via a softirq-driven IRQ emulation mechanism.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:23 -07:00
Ingo Molnar 77a5afecdb [PATCH] genirq: cleanup: no_irq_type cleanups
Clean up no_irq_type: share the NOP functions where possible, and properly
name the ack_bad() function.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:23 -07:00
Ingo Molnar 8d28bc751b [PATCH] genirq: doc: handle_IRQ_event() and __do_IRQ() comments
Document handle_IRQ_event() and __do_IRQ().

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:23 -07:00
Ingo Molnar c0ad90a32f [PATCH] genirq: add ->retrigger() irq op to consolidate hw_irq_resend()
Add ->retrigger() irq op to consolidate hw_irq_resend() implementations.
(Most architectures had it defined to NOP anyway.)

NOTE: ia64 needs testing. i386 and x86_64 tested.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:23 -07:00
Thomas Gleixner 096c8131c5 [PATCH] genirq: debug: better debug printout in enable_irq()
Make enable_irq() debug printouts user-readable.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:23 -07:00
Ingo Molnar 0d7012a968 [PATCH] genirq: cleanup: turn ARCH_HAS_IRQ_PER_CPU into CONFIG_IRQ_PER_CPU
Cleanup: change ARCH_HAS_IRQ_PER_CPU into a Kconfig method.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:23 -07:00
Ingo Molnar cd916d31cc [PATCH] genirq: cleanup: merge pending_irq_cpumask[] into irq_desc[]
Consolidation: remove the pending_irq_cpumask[NR_IRQS] array and move it into
the irq_desc[NR_IRQS].pending_mask field.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:22 -07:00
Ingo Molnar 4a733ee126 [PATCH] genirq: cleanup: merge irq_dir[], smp_affinity_entry[] into irq_desc[]
Consolidation: remove the irq_dir[NR_IRQS] and the smp_affinity_entry[NR_IRQS]
arrays and move them into the irq_desc[] array.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:22 -07:00
Ingo Molnar 34ffdb7233 [PATCH] genirq: cleanup: reduce irq_desc_t use, mark it obsolete
Cleanup: remove irq_desc_t use from the generic IRQ code, and mark it
obsolete.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:22 -07:00
Ingo Molnar 06fcb0c6fb [PATCH] genirq: cleanup: misc code cleanups
Assorted code cleanups to the generic IRQ code.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:22 -07:00
Ingo Molnar 2e60bbb6d5 [PATCH] genirq: cleanup: remove fastcall
Now that i386 defaults to regparm, explicit uses of fastcall are not needed
anymore.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:22 -07:00
Ingo Molnar a8553acd6c [PATCH] genirq: cleanup: remove irq_descp()
Cleanup: remove irq_descp() - explicit use of irq_desc[] is shorter and more
readable.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:22 -07:00
Ingo Molnar a53da52fd7 [PATCH] genirq: cleanup: merge irq_affinity[] into irq_desc[]
Consolidation: remove the irq_affinity[NR_IRQS] array and move it into the
irq_desc[NR_IRQS].affinity field.

[akpm@osdl.org: sparc64 build fix]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:22 -07:00
Ingo Molnar 74ffd553a3 [PATCH] genirq: sem2mutex probe_sem -> probing_active
Convert the irq auto-probing semaphore to a mutex.  (This allows us to find
probing API usage bugs sooner, via the mutex debugging code.)

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:21 -07:00
Ingo Molnar d1bef4ed5f [PATCH] genirq: rename desc->handler to desc->chip
This patch-queue improves the generic IRQ layer to be truly generic, by adding
various abstractions and features to it, without impacting existing
functionality.

While the queue can be best described as "fix and improve everything in the
generic IRQ layer that we could think of", and thus it consists of many
smaller features and lots of cleanups, the one feature that stands out most is
the new 'irq chip' abstraction.

The irq-chip abstraction is about describing and coding and IRQ controller
driver by mapping its raw hardware capabilities [and quirks, if needed] in a
straightforward way, without having to think about "IRQ flow"
(level/edge/etc.) type of details.

This stands in contrast with the current 'irq-type' model of genirq
architectures, which 'mixes' raw hardware capabilities with 'flow' details.
The patchset supports both types of irq controller designs at once, and
converts i386 and x86_64 to the new irq-chip design.

As a bonus side-effect of the irq-chip approach, chained interrupt controllers
(master/slave PIC constructs, etc.) are now supported by design as well.

The end result of this patchset intends to be simpler architecture-level code
and more consolidation between architectures.

We reused many bits of code and many concepts from Russell King's ARM IRQ
layer, the merging of which was one of the motivations for this patchset.

This patch:

rename desc->handler to desc->chip.

Originally i did not want to do this, because it's a big patch.  But having
both "desc->handler", "desc->handle_irq" and "action->handler" caused a
large degree of confusion and made the code appear alot less clean than it
truly is.

I have also attempted a dual approach as well by introducing a
desc->chip alias - but that just wasnt robust enough and broke
frequently.

So lets get over with this quickly.  The conversion was done automatically
via scripts and converts all the code in the kernel.

This renaming patch is the first one amongst the patches, so that the
remaining patches can stay flexible and can be merged and split up
without having some big monolithic patch act as a merge barrier.

[akpm@osdl.org: build fix]
[akpm@osdl.org: another build fix]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:21 -07:00
Jan Beulich 908dcecda1 [PATCH] adjust handle_IRR_event() return type
Correct the return type of handle_IRQ_event() (inconsistency noticed during
Xen development), and remove redundant declarations.  The return type
adjustment required breaking out the definition of irqreturn_t into a
separate header, in order to satisfy current include order dependencies.

Signed-off-by: Jan Beulich <jbeulich@novell.com>

Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ian Molton <spyro@f2s.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Hirokazu Takata <takata.hirokazu@renesas.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:43:08 -07:00
Andreas Mohr 83d4e6e7fb [PATCH] make noirqdebug/irqfixup __read_mostly, add (un)likely()
Signed-off-by: Andreas Mohr <andi@lisas.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:43:05 -07:00
Daniel Walker 89d0cf01c0 [PATCH] invert irq/migration.c brach prediction
If you get to that point in the code it means that desc->move_irq is set,
pending_irq_cpumask[irq] and cpu_online_map should have a value.  Still
pretty good chance anding those two you'll still have a value.  So these
two branch predictors should be inverted.

Signed-off-by: Daniel Walker <dwalker@mvista.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:43:04 -07:00
Zhang Yanmin 1b61b910e9 [PATCH] x86: kernel irq balance doesn't work
On i386, kernel irq balance doesn't work.

1) In function do_irq_balance, after kernel finds the min_loaded cpu but
   before calling set_pending_irq to really pin the selected_irq to the
   target cpu, kernel does a cpus_and with irq_affinity[selected_irq].
   Later on, when the irq is acked, kernel would calls
   move_native_irq=>desc->handler->set_affinity to change the irq affinity.
    However, every function pointed by
   hw_interrupt_type->set_affinity(unsigned int irq, cpumask_t cpumask)
   always changes irq_affinity[irq] to cpumask.  Next time when recalling
   do_irq_balance, it has to do cpu_ands again with
   irq_affinity[selected_irq], but irq_affinity[selected_irq] already
   becomes one cpu selected by the first irq balance.

2) Function balance_irq in file arch/i386/kernel/io_apic.c has the same
   issue.

[akpm@osdl.org: cleanups]
Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:57 -07:00
Andrew Morton 13e87ec686 [PATCH] request_irq(): remove warnings from irq probing
- Add new SA_PROBEIRQ which suppresses the new sharing-mismatch warning.
  Some drivers like to use request_irq() to find an unused interrupt slot.

- Use it in i82365.c

- Kill unused SA_PROBE.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-28 08:33:46 -07:00
Christoph Hellwig d824e66a9a [PATCH] build kernel/irq/migration.c only if CONFIG_GENERIC_PENDING_IRQ is set
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-11 06:18:41 -07:00
Ingo Molnar cd7b24bb18 [PATCH] warn if free_irq() is called from IRQ context
Warn if free_irq() is called in IRQ context - free_irq() can execute /proc
VFS work, which must not be done in IRQ context.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:56:53 -08:00
Dimitri Sivanich f516342745 [PATCH] Add SA_PERCPU_IRQ flag support
Add support for SA_PERCPU_IRQ (only mmtimer.c uses this at this stage).

Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:23:01 -08:00
Bryan Holty 501f2499b8 [PATCH] IRQ: prevent enabling of previously disabled interrupt
This fix prevents re-disabling and enabling of a previously disabled
interrupt.  On an SMP system with irq balancing enabled; If an interrupt is
disabled from within its own interrupt context with disable_irq_nosync and is
also earmarked for processor migration, the interrupt is blindly moved to the
other processor and enabled without regard for its current "enabled" state.
If there is an interrupt pending, it will unexpectedly invoke the irq handler
on the new irq owning processor (even though the irq was previously disabled)

The more intuitive fix would be to invoke disable_irq_nosync and
enable_irq, but since we already have the desc->lock from __do_IRQ, we
cannot call them directly.  Instead we can use the same logic to disable
and enable found in disable_irq_nosync and enable_irq, with regards to the
desc->depth.

This now prevents a disabled interrupt from being re-disabled, and more
importantly prevents a disabled interrupt from being incorrectly enabled on
a different processor.

Signed-off-by: Bryan Holty <lgeek@frontiernet.net>
Cc: Andi Kleen <ak@muc.de>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:22:55 -08:00
Andrew Morton c777ac5594 [PATCH] irq: uninline migration functions
Uninline some massive IRQ migration functions.  Put them in the new
kernel/irq/migration.c.

Cc: Andi Kleen <ak@muc.de>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:22:55 -08:00
Adrian Bunk 97a41e2612 [PATCH] kernel/: small cleanups
This patch contains the following cleanups:
- make needlessly global functions static
- every file should include the headers containing the prototypes for
  it's global functions

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:48 -08:00
Ivan Kokshaysky eee45269b0 [PATCH] Alpha: convert to generic irq framework (generic part)
Thanks to Christoph for doing most of the work.

This allows automatic SMP IRQ affinity assignment other than default "all
interrupts on all CPUs" which is rather expensive.  This might be useful if
the hardware can be programmed to distribute interrupts among different
CPUs, like Alpha does.

Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:40 -08:00
Matthew Wilcox c2b5a251b9 [PATCH] Check the irq number is within bounds
Most of the functions already check. Do the ones that didn't.

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-23 11:11:28 -08:00
Randy Dunlap 1e5d533142 [PATCH] more kernel-doc cleanups, additions
Various core kernel-doc cleanups:
- add missing function parameters in ipc, irq/manage, kernel/sys,
  kernel/sysctl, and mm/slab;
- move description to just above function for kernel_restart()

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:55 -08:00
Paul Mackerras beeca08738 Don't call a NULL ack function in the generic IRQ code.
Some IRQ controllers don't need an ack function (e.g. OpenPIC on
PPC platforms) and for them we'd rather not have the overhead
of doing an indirect call to a function that does nothing.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-09-28 20:29:44 +10:00
Karsten Wiese f26fdd5992 [PATCH] CHECK_IRQ_PER_CPU() to avoid dead code in __do_IRQ()
IRQ_PER_CPU is not used by all architectures.  This patch introduces the
macros ARCH_HAS_IRQ_PER_CPU and CHECK_IRQ_PER_CPU() to avoid the generation
of dead code in __do_IRQ().

ARCH_HAS_IRQ_PER_CPU is defined by architectures using IRQ_PER_CPU in their
include/asm_ARCH/irq.h file.

Through grepping the tree I found the following architectures currently use
IRQ_PER_CPU:

        cris, ia64, ppc, ppc64 and parisc.

Signed-off-by: Karsten Wiese <annabellesgarden@yahoo.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:29 -07:00
Ashok Raj 54d5d42404 [PATCH] x86/x86_64: deferred handling of writes to /proc/irqxx/smp_affinity
When handling writes to /proc/irq, current code is re-programming rte
entries directly. This is not recommended and could potentially cause
chipset's to lockup, or cause missing interrupts.

CONFIG_IRQ_BALANCE does this correctly, where it re-programs only when the
interrupt is pending. The same needs to be done for /proc/irq handling as well.
Otherwise user space irq balancers are really not doing the right thing.

- Changed pending_irq_balance_cpumask to pending_irq_migrate_cpumask for
  lack of a generic name.
- added move_irq out of IRQ_BALANCE, and added this same to X86_64
- Added new proc handler for write, so we can do deferred write at irq
  handling time.
- Display of /proc/irq/XX/smp_affinity used to display CPU_MASKALL, instead
  it now shows only active cpu masks, or exactly what was set.
- Provided a common move_irq implementation, instead of duplicating
  when using generic irq framework.

Tested on i386/x86_64 and ia64 with CONFIG_PCI_MSI turned on and off.
Tested UP builds as well.

MSI testing: tbd: I have cards, need to look for a x-over cable, although I
did test an earlier version of this patch.  Will test in a couple days.

Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Acked-by: Zwane Mwaikambo <zwane@holomorphy.com>
Grudgingly-acked-by: Andi Kleen <ak@muc.de>
Signed-off-by: Coywolf Qi Hunt <coywolf@lovecn.org>
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:15 -07:00
Alan Cox 200803dfe4 [PATCH] irqpoll
Anyone reporting a stuck IRQ should try these options.  Its effectiveness
varies we've found in the Fedora case.  Quite a few systems with misdescribed
IRQ routing just work when you use irqpoll.  It also fixes up the VIA systems
although thats now fixed with the VIA quirk (which we could just make default
as its what Redmond OS does but Linus didn't like it historically).

A small number of systems have jammed IRQ sources or misdescribes that cause
an IRQ that we have no handler registered anywhere for.  In those cases it
doesn't help.

Signed-off-by: Alan Cox <number6@the-village.bc.nu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 21:20:35 -07:00
Luca Falavigna 47f176fdaf [PATCH] Using msleep() instead of HZ
Use msleep() in a few places.

Signed-off-by: Luca Falavigna <dktrkranz@gmail.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28 21:20:29 -07:00
Adrian Bunk 52c1da3953 [PATCH] make various thing static
Another rollup of patches which give various symbols static scope

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-24 00:06:43 -07:00
Paolo 'Blaisorblade' Giarrusso b77d6adc92 [PATCH] uml: make hw_controller_type->release exist only for archs needing it
With Chris Wedgwood <cw@f00f.org>

As suggested by Chris, we can make the "just added" method ->release
conditional to UML only (better: to archs requesting it, i.e.  only UML
currently), so that other archs don't get this unneeded crud, and if UML
won't need it any more we can kill this.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
CC: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 19:07:32 -07:00
Paolo 'Blaisorblade' Giarrusso dbce706e25 [PATCH] uml: add and use generic hw_controller_type->release
With Chris Wedgwood <cw@f00f.org>

Currently UML must explicitly call the UML-specific
free_irq_by_irq_and_dev() for each free_irq call it's done.

This is needed because ->shutdown and/or ->disable are only called when the
last "action" for that irq is removed.

Instead, for UML shared IRQs (UML IRQs are very often, if not always,
shared), for each dev_id some setup is done, which must be cleared on the
release of that fd.  For instance, for each open console a new instance
(i.e.  new dev_id) of the same IRQ is requested().

Exactly, a fd is stored in an array (pollfds), which is after read by a
host thread and passed to poll().  Each event registered by poll() triggers
an interrupt.  So, for each free_irq() we must remove the corresponding
host fd from the table, which we do via this -release() method.

In this patch we add an appropriate hook for this, and remove all uses of
it by pointing the hook to the said procedure; this is safe to do since the
said procedure.

Also some cosmetic improvements are included.

This is heavily based on some work by Chris Wedgwood, which however didn't
get the patch merged for something I'd call a "misunderstanding" (the need
for this patch wasn't cleanly explained, thus adding the generic hook was
felt as undesirable).

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
CC: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 19:07:32 -07:00
John Hawkes b60c1f6ffd [PATCH] drop note_interrupt() for per-CPU for proper scaling
The "unhandled interrupts" catcher, note_interrupt(), increments a global
desc->irq_count and grossly damages scaling of very large systems, e.g.,
>192p ia64 Altix, because of this highly contented cacheline, especially
for timer interrupts.  384p is severely crippled, and 512p is unuseable.

All calls to note_interrupt() can be disabled by booting with "noirqdebug",
but this disables the useful interrupt checking for all interrupts.

I propose eliminating note_interrupt() for all per-CPU interrupts.  This
was the behavior of linux-2.6.10 and earlier, but in 2.6.11 a code
restructuring added a call to note_interrupt() for per-CPU interrupts.
Besides, note_interrupt() is a bit racy for concurrent CPU calls anyway, as
the desc->irq_count++ increment isn't atomic (which, if done, would make
scaling even worse).

Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-28 11:14:00 -07:00
Zhang, Yanmin 4f167fb491 [PATCH] spurious interrupt fix
On my IA64 machine, after kernel 2.6.12-rc3 boots, an edge-triggered
interrupt (IRQ 46) keeps triggered over and over again.  There is no IRQ 46
interrupt action handler.  It has lots of impact on performance.

Kernel 2.6.10 and its prior versions have no the problem.  Basically,
kernel 2.6.10 will mask the spurious edge interrupt if the interrupt is
triggered for the second time and its status includes
IRQ_DISABLE|IRQ_PENDING.

Originally, IA64 kernel has its own specific _irq_desc definitions in file
arch/ia64/kernel/irq.c.  The definition initiates _irq_desc[irq].status to
IRQ_DISABLE.  Since kernel 2.6.11, it was moved to architecture independent
codes, i.e.  kernel/irq/handle.c, but kernel/irq/handle.c initiates
_irq_desc[irq].status to 0 instead of IRQ_DISABLE.

Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-17 07:59:18 -07:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00