Commit Graph

648 Commits

Author SHA1 Message Date
Grant Likely
d6b0d1f705 irqdomain: Eliminate dedicated radix lookup functions
In preparation to remove the slow revmap path, eliminate the public
radix revmap lookup functions.  This simplifies the code and makes the
slowpath removal patch a lot simpler.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>
2012-07-11 16:16:00 +01:00
Grant Likely
98aa468e04 irqdomain: Support for static IRQ mapping and association.
This adds a new strict mapping API for supporting creation of linux IRQs
at existing positions within the domain. The new routines are as follows:

For dynamic allocation and insertion to specified ranges:

	- irq_create_identity_mapping()
	- irq_create_strict_mappings()

These will allocate and associate a range of linux IRQs at the specified
location. This can be used by controllers that have their own static linux IRQ
definitions to map a hwirq range to, as well as for platforms that wish to
establish 1:1 identity mapping between linux and hwirq space.

For insertion to specified ranges by platforms that do their own irq_desc
management:

	- irq_domain_associate()
	- irq_domain_associate_many()

These in turn call back in to the domain's ->map() routine, for further
processing by the platform. Disassociation of IRQs get handled through
irq_dispose_mapping() as normal.

With these in place it should be possible to begin migration of legacy IRQ
domains to linear ones, without requiring special handling for static vs
dynamic IRQ definitions in DT vs non-DT paths. This also makes it possible
for domains with static mappings to adopt whichever tree model best fits
their needs, rather than simply restricting them to linear revmaps.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
[grant.likely: Reorganized irq_domain_associate{,_many} to have all logic in one place]
[grant.likely: Add error checking for unallocated irq_descs at associate time]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>
2012-07-11 16:15:37 +01:00
Grant Likely
2a71a1a9da irqdomain: Always update revmap when setting up a virq
At irq_setup_virq() time all of the data needed to update the reverse
map is available, but the current code ignores it and relies upon the
slow path to insert revmap records.  This patch adds revmap updating
to the setup path so the slow path will no longer be necessary.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>
2012-07-11 16:15:34 +01:00
Grant Likely
913af20707 irqdomain: Split disassociating code into separate function
This patch moves the irq disassociation code out into a separate
function in preparation to extend irq_setup_virq to handle multiple
irqs and rename it for use by interrupt controller drivers.  The new
function will be used by irq_setup_virq() in its error path.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>
2012-07-11 16:15:34 +01:00
Dong Aisheng
22076c7712 irq_domain: correct a minor wrong comment for linear revmap
The revmap type should be linear for irq_domain_add_linear function.

Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-07-11 15:07:27 +01:00
Mark Brown
781d0f46d8 irq_domain: Standardise legacy/linear domain selection
A large proportion of interrupt controllers that support legacy mappings
do so because non-DT systems need to use fixed IRQ numbers when registering
devices via buses but can otherwise use a linear mapping. The interrupt
controller itself typically is not affected by the mapping used and best
practice is to use a linear mapping where possible so drivers frequently
select at runtime depending on if a legacy range has been allocated to
them.

Standardise this behaviour by providing irq_domain_register_simple() which
will allocate a linear mapping unless a positive first_irq is provided in
which case it will fall back to a legacy mapping. This helps make best
practice for irq_domain adoption clearer.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-07-11 14:59:17 +01:00
Grant Likely
aed98048bd irqdomain: Make ops->map hook optional
There isn't a really compelling reason to force ->map to be populated,
so allow it to be left unset.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>
2012-06-17 15:41:57 -06:00
Grant Likely
7325570471 irqdomain: Remove unnecessary test for IRQ_DOMAIN_MAP_LEGACY
Where irq_domain_associate() is called in irq_create_mapping, there is
no need to test for IRQ_DOMAIN_MAP_LEGACY because it is already tested
for earlier in the routine.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>
2012-06-15 12:08:09 -06:00
Paul Mundt
5ca4db61e8 irqdomain: Simple NUMA awareness.
While common irqdesc allocation is node aware, the irqdomain code is not.

Presently we observe a number of regressions/inconsistencies on
NUMA-capable platforms:

- Platforms using irqdomains with legacy mappings, where the
  irq_descs are allocated node-local and the irqdomain data
  structure is not.

- Drivers implementing irqdomains will lose node locality
  regardless of the underlying struct device's node id.

This plugs in NUMA node id proliferation across the various allocation
callsites by way of_node_to_nid() node lookup. While of_node_to_nid()
does the right thing for OF-capable platforms it doesn't presently handle
the non-DT case. This is trivially dealt with by simply wraping in to
numa_node_id() unconditionally.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-06-15 12:08:00 -06:00
Grant Likely
efd68e7254 devicetree: add helper inline for retrieving a node's full name
The pattern (np ? np->full_name : "<none>") is rather common in the
kernel, but can also make for quite long lines.  This patch adds a new
inline function, of_node_full_name() so that the test for a valid node
pointer doesn't need to be open coded at all call sites.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
2012-06-15 11:44:03 -06:00
Linus Torvalds
9171c670b4 Merge branches 'irq-urgent-for-linus' and 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq and smpboot updates from Thomas Gleixner:
 "Just cleanup patches with no functional change and a fix for suspend
  issues."

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Introduce irq_do_set_affinity() to reduce duplicated code
  genirq: Add IRQS_PENDING for nested and simple irq

* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  smpboot, idle: Fix comment mismatch over idle_threads_init()
  smpboot, idle: Optimize calls to smp_processor_id() in idle_threads_init()
2012-06-04 11:36:51 -07:00
Linus Torvalds
fb21affa49 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull second pile of signal handling patches from Al Viro:
 "This one is just task_work_add() series + remaining prereqs for it.

  There probably will be another pull request from that tree this
  cycle - at least for helpers, to get them out of the way for per-arch
  fixes remaining in the tree."

Fix trivial conflict in kernel/irq/manage.c: the merge of Andrew's pile
had brought in commit 97fd75b7b8 ("kernel/irq/manage.c: use the
pr_foo() infrastructure to prefix printks") which changed one of the
pr_err() calls that this merge moves around.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
  keys: kill task_struct->replacement_session_keyring
  keys: kill the dummy key_replace_session_keyring()
  keys: change keyctl_session_to_parent() to use task_work_add()
  genirq: reimplement exit_irq_thread() hook via task_work_add()
  task_work_add: generic process-context callbacks
  avr32: missed _TIF_NOTIFY_RESUME on one of do_notify_resume callers
  parisc: need to check NOTIFY_RESUME when exiting from syscall
  move key_repace_session_keyring() into tracehook_notify_resume()
  TIF_NOTIFY_RESUME is defined on all targets now
2012-05-31 18:47:30 -07:00
Andrew Morton
97fd75b7b8 kernel/irq/manage.c: use the pr_foo() infrastructure to prefix printks
Use the module-wide pr_fmt() mechanism rather than open-coding "genirq: "
everywhere.

Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31 17:49:26 -07:00
Linus Torvalds
b343c8beec irqdomain changes for v3.5 merge window
Minor changes and fixups for irqdomain infrastructure.  Most
 important change adds ability to remove registered irqdomain.
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Merge tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6

Pull irqdomain changes from Grant Likely:
 "Minor changes and fixups for irqdomain infrastructure.  The most
  important change adds the ability to remove a registered irqdomain."

* tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6:
  irqdomain: Document size parameter of irq_domain_add_linear()
  irqdomain: trivial pr_fmt conversion.
  irqdomain: Kill off duplicate definitions.
  irqdomain: Make irq_domain_simple_map() static.
  irqdomain: Export remaining public API symbols.
  irqdomain: Support removal of IRQ domains.
2012-05-24 13:55:24 -07:00
Jiang Liu
818b0f3bfb genirq: Introduce irq_do_set_affinity() to reduce duplicated code
All invocations of chip->irq_set_affinity() are doing the same return
value checks. Let them all use a common function.

[ tglx: removed the silly likely while at it ]

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Keping Chen <chenkeping@huawei.com>
Link: http://lkml.kernel.org/r/1333120296-13563-3-git-send-email-jiang.liu@huawei.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-05-24 22:36:40 +02:00
Ning Jiang
23812b9d9e genirq: Add IRQS_PENDING for nested and simple irq
Every interrupt which is an active wakeup source needs the ability to
abort suspend if there is a pending irq. Right now only edge and level
irqs can do that.

            |
       +---------+
       |   INTC  |
       +---------+
               | GPIO_IRQ
            +------------+
            |  gpio-exp  |
            +------------+
              |        |
         GPIO0_IRQ  GPIO1_IRQ

In the above diagram, gpio expander has irq number GPIO_IRQ, it is
connected with two sub GPIO pins, GPIO0 and GPIO1.

During suspend, we set IRQF_NO_SUSPEND for GPIO_IRQ so that gpio
expander driver can handle the sub irq GPIO0_IRQ and GPIO1_IRQ, and
these two irqs themselves can further be handled by simple or nested
irq in some drivers(typically gpio and mfd driver). If they are used
as wakeup sources during suspend, we want them to be able to abort
suspend too.

Setting IRQS_PENDING flag in handle_nested_irq() and handle_simple_irq()
when the irq is disabled allows check_wakeup_irqs() to identify such
irqs as source for aborting suspend.

Signed-off-by: Ning Jiang <ning.n.jiang@gmail.com>
Cc: rjw@sisk.pl
Link: http://lkml.kernel.org/r/CAH3Oq6T905%2B3fkF43NAMMFvJvq7dsk_so6T2vQ8ZJrA5xiU3YA@mail.gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-05-24 22:27:45 +02:00
Oleg Nesterov
4d1d61a6b2 genirq: reimplement exit_irq_thread() hook via task_work_add()
exit_irq_thread() and task->irq_thread are needed to handle the unexpected
(and unlikely) exit of irq-thread.

We can use task_work instead and make this all private to
kernel/irq/manage.c, cleanup plus micro-optimization.

1. rename exit_irq_thread() to irq_thread_dtor(), make it
   static, and move it up before irq_thread().

2. change irq_thread() to do task_work_add(irq_thread_dtor)
   at the start and task_work_cancel() before return.

   tracehook_notify_resume() can never play with kthreads,
   only do_exit()->exit_task_work() can call the callback
   and this is what we want.

3. remove task_struct->irq_thread and the special hook
   in do_exit().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alexander Gordeev <agordeev@redhat.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Smith <dsmith@redhat.com>
Cc: "Frank Ch. Eigler" <fche@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-23 22:11:12 -04:00
Linus Torvalds
3a8580f820 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML updates from Richard Weinberger:
 "Most changes are bug fixes and cleanups"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: missing checks of __put_user()/__get_user() return values
  um: stub_rt_sigsuspend isn't needed these days anymore
  um/x86: merge (and trim) 32- and 64-bit variants of ptrace.h
  irq: Remove irq_chip->release()
  um: Remove CONFIG_IRQ_RELEASE_METHOD
  um: Remove usage of irq_chip->release()
  um: Implement um_free_irq()
  um: Fix __swp_type()
  um: Implement a custom pte_same() function
  um: Add BUG() to do_ops()'s error path
  um: Remove unused variables
  um: bury unused _TIF_RESTORE_SIGMASK
  um: wrong sigmask saved in case of multiple sigframes
  um: add TIF_NOTIFY_RESUME
  um: ->restart_block.fn needs to be reset on sigreturn
2012-05-23 09:01:41 -07:00
Linus Torvalds
471368557a Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core irq changes from Ingo Molnar:
 "A collection of small fixes."

By Thomas Gleixner
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hexagon: Remove select of not longer existing Kconfig switches
  arm: Select core options instead of redefining them
  genirq: Do not consider disabled wakeup irqs
  genirq: Allow check_wakeup_irqs to notice level-triggered interrupts
  genirq: Be more informative on irq type mismatch
  genirq: Reject bogus threaded irq requests
  genirq: Streamline irq_action
2012-05-21 20:33:19 -07:00
Richard Weinberger
875682648b irq: Remove irq_chip->release()
As it's only user (UML) does no longer need it we can get
rid of it.

Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2012-05-21 21:09:38 +02:00
Mark Brown
a87487e687 irqdomain: Document size parameter of irq_domain_add_linear()
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-05-19 13:07:51 -06:00
Paul Mundt
54a9058860 irqdomain: trivial pr_fmt conversion.
Convert to pr_fmt before things start to get out of hand and some
janitors start getting overly excited.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-05-19 12:59:15 -06:00
Paul Mundt
5c5806e50b irqdomain: Make irq_domain_simple_map() static.
Presently irq_domain_simple_map() isn't labelled as static, but there's
no definition for it in the public irqdomain header either. At present
all in-tree ->map users have meaningful work to do, and all others are
using irq_domain_simple_ops directly. Make it static for now, as it can
always be exported and added to the public API later.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-05-19 12:35:33 -06:00
Paul Mundt
ecd84eb20a irqdomain: Export remaining public API symbols.
modules making use of irq domains at the very least need access to the
add/remove/lookup routines, though there's nothing preventing them from
using the remainder of the public API, either.

The current set of exports seem primarily geared at DT-enabled platforms
using DT-backed IRQ domains, where many of the API accesses are hidden
away in OF code. The non-DT cases need to do most of this on their own.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-05-19 12:34:38 -06:00
Paul Mundt
58ee99ada2 irqdomain: Support removal of IRQ domains.
Now that IRQ domains are being used by modules it's necessary to support
removing them, too. This adds a new irq_domain_remove() routine for doing
the bulk of the heavy lifting. It's left as an exercise to the caller to
ensure all mappings have been appropriatey disposed of before attempting
to remove the domain.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-05-19 12:32:35 -06:00
Jiri Kosina
3911ff30f5 genirq: export handle_edge_irq() and irq_to_desc()
Export handle_edge_irq() and irq_to_desc() to modules to allow them to
do things such as

	__irq_set_handler_locked(...., handle_edge_irq);

This fixes

	ERROR: "handle_edge_irq" [drivers/gpio/gpio-pch.ko] undefined!
	ERROR: "irq_to_desc" [drivers/gpio/gpio-pch.ko] undefined!

when gpio-pch is being built as a module.

This was introduced by commit df9541a60a ("gpio: pch9: Use proper flow
type handlers") that added

	__irq_set_handler_locked(d->irq, handle_edge_irq);

but handle_edge_irq() was not exported for modules (and inlined
__irq_set_handler_locked() requires irq_to_desc() exported as well)

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-15 08:10:07 -07:00
Thomas Gleixner
9c6079aa1b genirq: Do not consider disabled wakeup irqs
If an wakeup interrupt has been disabled before the suspend code
disables all interrupts then we have to ignore the pending flag.

Otherwise we would abort suspend over and over as nothing clears the
pending flag because the interrupt is disabled.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: NeilBrown <neilb@suse.de>
2012-05-04 23:38:50 +02:00
Thomas Gleixner
d4dc0f90d2 genirq: Allow check_wakeup_irqs to notice level-triggered interrupts
Level triggered interrupts do not cause IRQS_PENDING to be set when
they fire while "disabled" as the 'pending' state is always present in
the level - they automatically refire where re-enabled.

However the IRQS_PENDING flag is also used to abort a suspend cycle -
if any 'is_wakeup_set' interrupt is PENDING, check_wakeup_irqs() will
cause suspend to abort. Without IRQS_PENDING, suspend won't abort.

Consequently, level-triggered interrupts that fire during the 'noirq'
phase of suspend do not currently abort suspend.

So set IRQS_PENDING even for level triggered interrupts, and make sure
to clear the flag in check_irq_resend.

[ Changelog by courtesy of Neil ]

Tested-by: NeilBrown <neilb@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-05-04 23:38:50 +02:00
Paul Gortmaker
9f3045eca8 irq: hide debug macros so they don't collide with others.
The file kernel/irq/debug.h temporarily defines P, PS, PD
and then undefines them.  However these names aren't really
"internal" enough, and collide with other more legit users
such as the ones in the xtensa arch, causing:

In file included from kernel/irq/internals.h:58:0,
                 from kernel/irq/irqdesc.c:18:
kernel/irq/debug.h:8:0: warning: "PS" redefined [enabled by default]
arch/xtensa/include/asm/regs.h:59:0: note: this is the location of the previous definition

Add a handful of underscores to do a better job of hiding these
temporary macros.

Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-04-23 12:30:03 -04:00
Thomas Gleixner
f5d89470f9 genirq: Be more informative on irq type mismatch
We require that shared interrupts agree on a few flag settings. Right
now we silently return with an error code without giving any hint why
we reject it.

Make the printout unconditionally and actually useful by printing the
flags of the new and the already registered action.

Convert all printks to pr_* and use a proper prefix while at it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-04-19 13:56:56 +02:00
Thomas Gleixner
1c6c69525b genirq: Reject bogus threaded irq requests
Requesting a threaded interrupt without a primary handler and without
IRQF_ONESHOT set is dangerous.

The core will use the default primary handler for it, which merily
wakes the thread. For a level type interrupt this results in an
interrupt storm, because the interrupt line is reenabled after the
primary handler runs. The device has still the line asserted, which
brings us back into the primary handler.

While this works for edge type interrupts, we play it safe and reject
unconditionally because we can't say for sure which type this
interrupt really has. The type flags are unreliable as the underlying
chip implementation can override them. And we cannot assume that
developers using that interface know what they are doing.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-04-19 13:56:56 +02:00
Grant Likely
5269a9ab7d irq_domain: fix type mismatch in debugfs output format
sizeof(void*) returns an unsigned long, but it was being used as a width parameter to a "%-*s" format string which requires an int.  On 64 bit platforms this causes a type mismatch:

    linux/kernel/irq/irqdomain.c:575: warning: field width should have type
    'int', but argument 6 has type 'long unsigned int'

This change casts the size to an int so printf gets the right data type.

Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: David Daney <david.daney@cavium.com>
2012-04-12 16:25:48 -06:00
Grant Likely
6fa6c8e25e irq_domain: Move irq_virq_count into NOMAP revmap
This patch replaces the old global setting of irq_virq_count that is only
used by the NOMAP mapping and instead uses a revmap_data property so that
the maximum NOMAP allocation can be set per NOMAP irq_domain.

There is exactly one user of irq_virq_count in-tree right now: PS3.
Also, irq_virq_count is only useful for the NOMAP mapping.  So,
instead of having a single global irq_virq_count values, this change
drops it entirely and added a max_irq argument to irq_domain_add_nomap().
That makes it a property of an individual nomap irq domain instead of
a global system settting.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
2012-04-12 00:37:48 -06:00
Grant Likely
15e06bf64f irqdomain: Fix debugfs formatting
This patch fixes the irq_domain_mapping debugfs output to pad pointer
values with leading zeros so that pointer values are displayed
correctly.  Otherwise you get output similar to "0x 5e0000000000000".
Also, when the irq_domain is set to 'null'

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: David Daney <david.daney@cavium.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
2012-04-11 01:01:45 -06:00
Mika Westerberg
ac5830a33f irq_domain: correct the debugfs file name
The actual name of the irq_domain mapping debugfs file is
"irq_domain_mapping" not "virq_mapping".

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-04-10 22:39:17 -06:00
David Daney
5b7526e3a6 irq/irq_domain: Quit ignoring error returns from irq_alloc_desc_from().
In commit 4bbdd45a (irq_domain/powerpc: eliminate irq_map; use
irq_alloc_desc() instead) code was added that ignores error returns
from irq_alloc_desc_from() by (silently) casting the return value to
unsigned.  The negitive value error return now suddenly looks like a
valid irq number.

Commits cc79ca69 (irq_domain: Move irq_domain code from powerpc to
kernel/irq) and 1bc04f2c (irq_domain: Add support for base irq and
hwirq in legacy mappings) move this code to its current location in
irqdomain.c

The result of all of this is a null pointer dereference OOPS if one of
the error cases is hit.

The fix: Don't cast away the negativeness of the return value and then
check for errors.

Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
[grant.likely: dropped addition of new 'irq' variable]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-04-10 22:39:16 -06:00
Linus Torvalds
f558c27238 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull genirq updates from Thomas Gleixner.

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Adjust irq thread affinity on IRQ_SET_MASK_OK_NOCOPY return value
  genirq: Respect NUMA node affinity in setup_irq_irq affinity()
  genirq: Get rid of unneeded force parameter in irq_finalize_oneshot()
  genirq: Minor readablity improvement in irq_wake_thread()
2012-03-30 18:08:05 -07:00
Jiang Liu
f5cb92ac82 genirq: Adjust irq thread affinity on IRQ_SET_MASK_OK_NOCOPY return value
irq_move_masked_irq() checks the return code of
chip->irq_set_affinity() only for 0, but IRQ_SET_MASK_OK_NOCOPY is
also a valid return code, which is there to avoid a redundant copy of
the cpumask. But in case of IRQ_SET_MASK_OK_NOCOPY we not only avoid
the redundant copy, we also fail to adjust the thread affinity of an
eventually threaded interrupt handler.

Handle IRQ_SET_MASK_OK (==0) and IRQ_SET_MASK_OK_NOCOPY(==1) return
values correctly by checking the valid return values seperately.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Keping Chen <chenkeping@huawei.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1333120296-13563-2-git-send-email-jiang.liu@huawei.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-30 23:13:46 +02:00
Linus Torvalds
12679a2d7e Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm
Pull more ARM updates from Russell King.

This got a fair number of conflicts with the <asm/system.h> split, but
also with some other sparse-irq and header file include cleanups.  They
all looked pretty trivial, though.

* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (59 commits)
  ARM: fix Kconfig warning for HAVE_BPF_JIT
  ARM: 7361/1: provide XIP_VIRT_ADDR for no-MMU builds
  ARM: 7349/1: integrator: convert to sparse irqs
  ARM: 7259/3: net: JIT compiler for packet filters
  ARM: 7334/1: add jump label support
  ARM: 7333/2: jump label: detect %c support for ARM
  ARM: 7338/1: add support for early console output via semihosting
  ARM: use set_current_blocked() and block_sigmask()
  ARM: exec: remove redundant set_fs(USER_DS)
  ARM: 7332/1: extract out code patch function from kprobes
  ARM: 7331/1: extract out insn generation code from ftrace
  ARM: 7330/1: ftrace: use canonical Thumb-2 wide instruction format
  ARM: 7351/1: ftrace: remove useless memory checks
  ARM: 7316/1: kexec: EOI active and mask all interrupts in kexec crash path
  ARM: Versatile Express: add NO_IOPORT
  ARM: get rid of asm/irq.h in asm/prom.h
  ARM: 7319/1: Print debug info for SIGBUS in user faults
  ARM: 7318/1: gic: refactor irq_start assignment
  ARM: 7317/1: irq: avoid NULL check in for_each_irq_desc loop
  ARM: 7315/1: perf: add support for the Cortex-A7 PMU
  ...
2012-03-29 16:53:48 -07:00
Grant Likely
092b2fb076 irqdomain: Remove powerpc dependency from debugfs file
The debugfs code is really generic for all platforms.  This patch removes the
powerpc-specific directory reference and makes it available to all
architectures.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-03-29 14:31:02 -06:00
Prarit Bhargava
241fc640be genirq: Respect NUMA node affinity in setup_irq_irq affinity()
We respect node affinity of devices already in the irq descriptor
allocation, but we ignore it for the initial interrupt affinity
setup, so the interrupt might be routed to a different node.

Restrict the default affinity mask to the node on which the irq
descriptor is allocated.

[ tglx: Massaged changelog ]

Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Link: http://lkml.kernel.org/r/1332788538-17425-1-git-send-email-prarit@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-29 11:31:53 +02:00
Alexander Gordeev
f3f79e38d5 genirq: Get rid of unneeded force parameter in irq_finalize_oneshot()
The only place irq_finalize_oneshot() is called with force parameter set
is the threaded handler error exit path. But IRQTF_RUNTHREAD is dropped
at this point and irq_wake_thread() is not going to set it again,
since PF_EXITING is set for this thread already. So irq_finalize_oneshot()
will drop the threads bit in threads_oneshot anyway and hence the force
parameter is superfluous.

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Link: http://lkml.kernel.org/r/20120321162234.GP24806@dhcp-26-207.brq.redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-29 11:31:53 +02:00
Alexander Gordeev
69592db298 genirq: Minor readablity improvement in irq_wake_thread()
exit_irq_thread() clears IRQTF_RUNTHREAD flag and drops the thread's bit in
desc->threads_oneshot then. The bit must not be set again in between and it
does not, since irq_wake_thread() sees PF_EXITING flag first and returns.

Due to above the order or checking PF_EXITING and IRQTF_RUNTHREAD flags in
irq_wake_thread() is important. This change just makes it more visible in the
source code.

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Link: http://lkml.kernel.org/r/20120321162212.GO24806@dhcp-26-207.brq.redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-29 11:31:52 +02:00
Linus Torvalds
c207f3a431 Generialize powerpc's irq_host as irq_domain
This branch takes the PowerPC irq_host infrastructure (reverse mapping
 from Linux IRQ numbers to hardware irq numbering), generalizes it,
 renames it to irq_domain, and makes it available to all architectures.
 
 Originally the plan has been to create an all-new irq_domain
 implementation which addresses some of the powerpc shortcomings such
 as not handling 1:1 mappings well, but doing that proved to be far
 more difficult and invasive than generalizing the working code and
 refactoring it in-place.  So, this branch rips out the 'new'
 irq_domain and replaces it with the modified powerpc version (in a
 fully bisectable way of course).  It converts all users over to the
 new API and makes irq_domain selectable on any architecture.
 
 No architecture is forced to enable irq_domain, but the infrastructure
 is required for doing OpenFirmware style irq translations.  It will
 even work on SPARC even though SPARC has it's own mechanism for
 translating irqs at boot time.  MIPS, microblaze, embedded x86 and c6x
 are converted too.
 
 The resulting irq_domain code is probably still too verbose and can be
 optimized more, but that can be done incrementally and is a task for
 follow-on patches.
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Merge tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6

Pull irq_domain support for all architectures from Grant Likely:
 "Generialize powerpc's irq_host as irq_domain

  This branch takes the PowerPC irq_host infrastructure (reverse mapping
  from Linux IRQ numbers to hardware irq numbering), generalizes it,
  renames it to irq_domain, and makes it available to all architectures.

  Originally the plan has been to create an all-new irq_domain
  implementation which addresses some of the powerpc shortcomings such
  as not handling 1:1 mappings well, but doing that proved to be far
  more difficult and invasive than generalizing the working code and
  refactoring it in-place.  So, this branch rips out the 'new'
  irq_domain and replaces it with the modified powerpc version (in a
  fully bisectable way of course).  It converts all users over to the
  new API and makes irq_domain selectable on any architecture.

  No architecture is forced to enable irq_domain, but the infrastructure
  is required for doing OpenFirmware style irq translations.  It will
  even work on SPARC even though SPARC has it's own mechanism for
  translating irqs at boot time.  MIPS, microblaze, embedded x86 and c6x
  are converted too.

  The resulting irq_domain code is probably still too verbose and can be
  optimized more, but that can be done incrementally and is a task for
  follow-on patches."

* tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6: (31 commits)
  dt: fix twl4030 for non-dt compile on x86
  mfd: twl-core: Add IRQ_DOMAIN dependency
  devicetree: Add empty of_platform_populate() for !CONFIG_OF_ADDRESS (sparc)
  irq_domain: Centralize definition of irq_dispose_mapping()
  irq_domain/mips: Allow irq_domain on MIPS
  irq_domain/x86: Convert x86 (embedded) to use common irq_domain
  ppc-6xx: fix build failure in flipper-pic.c and hlwd-pic.c
  irq_domain/microblaze: Convert microblaze to use irq_domains
  irq_domain/powerpc: Replace custom xlate functions with library functions
  irq_domain/powerpc: constify irq_domain_ops
  irq_domain/c6x: Use library of xlate functions
  irq_domain/c6x: constify irq_domain structures
  irq_domain/c6x: Convert c6x to use generic irq_domain support.
  irq_domain: constify irq_domain_ops
  irq_domain: Create common xlate functions that device drivers can use
  irq_domain: Remove irq_domain_add_simple()
  irq_domain: Remove 'new' irq_domain in favour of the ppc one
  mfd: twl-core.c: Fix the number of interrupts managed by twl4030
  of/address: add empty static inlines for !CONFIG_OF
  irq_domain: Add support for base irq and hwirq in legacy mappings
  ...
2012-03-21 10:27:19 -07:00
Linus Torvalds
9c2b957db1 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf events changes for v3.4 from Ingo Molnar:

 - New "hardware based branch profiling" feature both on the kernel and
   the tooling side, on CPUs that support it.  (modern x86 Intel CPUs
   with the 'LBR' hardware feature currently.)

   This new feature is basically a sophisticated 'magnifying glass' for
   branch execution - something that is pretty difficult to extract from
   regular, function histogram centric profiles.

   The simplest mode is activated via 'perf record -b', and the result
   looks like this in perf report:

	$ perf record -b any_call,u -e cycles:u branchy

	$ perf report -b --sort=symbol
	    52.34%  [.] main                   [.] f1
	    24.04%  [.] f1                     [.] f3
	    23.60%  [.] f1                     [.] f2
	     0.01%  [k] _IO_new_file_xsputn    [k] _IO_file_overflow
	     0.01%  [k] _IO_vfprintf_internal  [k] _IO_new_file_xsputn
	     0.01%  [k] _IO_vfprintf_internal  [k] strchrnul
	     0.01%  [k] __printf               [k] _IO_vfprintf_internal
	     0.01%  [k] main                   [k] __printf

   This output shows from/to branch columns and shows the highest
   percentage (from,to) jump combinations - i.e.  the most likely taken
   branches in the system.  "branches" can also include function calls
   and any other synchronous and asynchronous transitions of the
   instruction pointer that are not 'next instruction' - such as system
   calls, traps, interrupts, etc.

   This feature comes with (hopefully intuitive) flat ascii and TUI
   support in perf report.

 - Various 'perf annotate' visual improvements for us assembly junkies.
   It will now recognize function calls in the TUI and by hitting enter
   you can follow the call (recursively) and back, amongst other
   improvements.

 - Multiple threads/processes recording support in perf record, perf
   stat, perf top - which is activated via a comma-list of PIDs:

	perf top -p 21483,21485
	perf stat -p 21483,21485 -ddd
	perf record -p 21483,21485

 - Support for per UID views, via the --uid paramter to perf top, perf
   report, etc.  For example 'perf top --uid mingo' will only show the
   tasks that I am running, excluding other users, root, etc.

 - Jump label restructurings and improvements - this includes the
   factoring out of the (hopefully much clearer) include/linux/static_key.h
   generic facility:

	struct static_key key = STATIC_KEY_INIT_FALSE;

	...

	if (static_key_false(&key))
	        do unlikely code
	else
	        do likely code

	...
	static_key_slow_inc();
	...
	static_key_slow_inc();
	...

   The static_key_false() branch will be generated into the code with as
   little impact to the likely code path as possible.  the
   static_key_slow_*() APIs flip the branch via live kernel code patching.

   This facility can now be used more widely within the kernel to
   micro-optimize hot branches whose likelihood matches the static-key
   usage and fast/slow cost patterns.

 - SW function tracer improvements: perf support and filtering support.

 - Various hardenings of the perf.data ABI, to make older perf.data's
   smoother on newer tool versions, to make new features integrate more
   smoothly, to support cross-endian recording/analyzing workflows
   better, etc.

 - Restructuring of the kprobes code, the splitting out of 'optprobes',
   and a corner case bugfix.

 - Allow the tracing of kernel console output (printk).

 - Improvements/fixes to user-space RDPMC support, allowing user-space
   self-profiling code to extract PMU counts without performing any
   system calls, while playing nice with the kernel side.

 - 'perf bench' improvements

 - ... and lots of internal restructurings, cleanups and fixes that made
   these features possible.  And, as usual this list is incomplete as
   there were also lots of other improvements

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (120 commits)
  perf report: Fix annotate double quit issue in branch view mode
  perf report: Remove duplicate annotate choice in branch view mode
  perf/x86: Prettify pmu config literals
  perf report: Enable TUI in branch view mode
  perf report: Auto-detect branch stack sampling mode
  perf record: Add HEADER_BRANCH_STACK tag
  perf record: Provide default branch stack sampling mode option
  perf tools: Make perf able to read files from older ABIs
  perf tools: Fix ABI compatibility bug in print_event_desc()
  perf tools: Enable reading of perf.data files from different ABI rev
  perf: Add ABI reference sizes
  perf report: Add support for taken branch sampling
  perf record: Add support for sampling taken branch
  perf tools: Add code to support PERF_SAMPLE_BRANCH_STACK
  x86/kprobes: Split out optprobe related code to kprobes-opt.c
  x86/kprobes: Fix a bug which can modify kernel code permanently
  x86/kprobes: Fix instruction recovery on optimized path
  perf: Add callback to flush branch_stack on context switch
  perf: Disable PERF_SAMPLE_BRANCH_* when not supported
  perf/x86: Add LBR software filter support for Intel CPUs
  ...
2012-03-20 10:29:15 -07:00
Thomas Gleixner
e04268b0ef genirq: Remove paranoid warnons and bogus fixups
Alexander pointed out that the warnons in the regular exit path are
bogus and the thread_mask one actually could be triggered when
__setup_irq() hands out that thread_mask again after __free_irq()
dropped irq_desc->lock.

Thinking more about it, neither IRQTF_RUNTHREAD nor the bit in
thread_mask can be set as this is the regular exit path. We come here
due to:
	__free_irq()
	   remove action from desc
	   synchronize_irq()
	   kthread_stop()

So synchronize_irq() makes sure that the thread finished running and
cleaned up both the thread_active count and thread_mask. After that
point nothing can set IRQTF_RUNTHREAD on this action. So the warnons
and the cleanups are pointless.

Reported-by: Alexander Gordeev <agordeev@redhat.com>
Cc: Ido Yariv <ido@wizery.com>
Link: http://lkml.kernel.org/r/20120315190755.GA6732@dhcp-26-207.brq.redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-16 11:27:28 +01:00
Ido Yariv
7140ea1980 genirq: Flush the irq thread on synchronization
The current implementation does not always flush the threaded handler
when disabling the irq. In case the irq handler was called, but the
threaded handler hasn't started running yet, the interrupt will be
flagged as pending, and the handler will not run. This implementation
has some issues:

First, if the interrupt is a wake source and flagged as pending, the
system will not be able to suspend.

Second, when quickly disabling and re-enabling the irq, the threaded
handler might continue to run after the irq is re-enabled without the
irq handler being called first. This might be an unexpected behavior.

In addition, it might be counter-intuitive that the threaded handler
will not be called even though the irq handler was called and returned
IRQ_WAKE_THREAD.

Fix this by always waiting for the threaded handler to complete in
synchronize_irq().

[ tglx: Massaged comments, added WARN_ONs and the missing
  	IRQTF_RUNTHREAD check in exit_irq_thread() ]

Signed-off-by: Ido Yariv <ido@wizery.com>
Link: http://lkml.kernel.org/r/1322843052-7166-1-git-send-email-ido@wizery.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-14 11:56:20 +01:00
Thomas Gleixner
df8d291f28 Merge branch 'linus' into irq/core
Reason: Get upstream fixes integrated before further modifications.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-13 16:35:16 +01:00
Ingo Molnar
35239e23c6 Merge branch 'perf/urgent' into perf/core
Merge reason: We are going to queue up a dependent patch.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-03-12 20:44:11 +01:00
Alexander Gordeev
5234ffb9f7 genirq: Get rid of unnecessary IRQTF_DIED flag
Currently IRQTF_DIED flag is set when a IRQ thread handler calls do_exit()
But also PF_EXITING per process flag gets set when a thread exits. This
fix eliminates the duplicate by using PF_EXITING flag.

Also, there is a race condition in exit_irq_thread(). In case a thread's
bit is cleared in desc->threads_oneshot (and the IRQ line gets unmasked),
but before IRQTF_DIED flag is set, a new interrupt might come in and set
just cleared bit again, this time forever. This fix throws IRQTF_DIED flag
away, eliminating the race as a result.

[ tglx: Test THREAD_EXITING first as suggested by Oleg ]

Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Link: http://lkml.kernel.org/r/20120309135958.GD2114@dhcp-26-207.brq.redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-03-09 17:19:09 +01:00