87 Commits

Author SHA1 Message Date
Helge Deller
b1bef1388c parisc: irq: Make irq_stack_union static to avoid sparse warning
Signed-off-by: Helge Deller <deller@gmx.de>
2023-08-31 22:36:12 +02:00
Helge Deller
bcfaf17f18 parisc: irq: Add irq-related function declarations
Move function declarations for do_cpu_irq_mask(), timer_interrupt() and
ipi_interrupt() to header file.

Signed-off-by: Helge Deller <deller@gmx.de>
2023-06-30 17:14:15 +02:00
Sebastian Andrzej Siewior
8cbb2b50ee asm-generic: Conditionally enable do_softirq_own_stack() via Kconfig.
Remove the CONFIG_PREEMPT_RT symbol from the ifdef around
do_softirq_own_stack() and move it to Kconfig instead.

Enable softirq stacks based on SOFTIRQ_ON_OWN_STACK which depends on
HAVE_SOFTIRQ_ON_OWN_STACK and its default value is set to !PREEMPT_RT.
This ensures that softirq stacks are not used on PREEMPT_RT and avoids
a 'select' statement on an option which has a 'depends' statement.

Link: https://lore.kernel.org/YvN5E%2FPrHfUhggr7@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-09-05 17:20:55 +02:00
Linus Torvalds
3bd6e5854b asm-generic: updates for 6.0
There are three independent sets of changes:
 
  - Sai Prakash Ranjan adds tracing support to the asm-generic
    version of the MMIO accessors, which is intended to help
    understand problems with device drivers and has been part
    of Qualcomm's vendor kernels for many years.
 
  - A patch from Sebastian Siewior to rework the handling of
    IRQ stacks in softirqs across architectures, which is
    needed for enabling PREEMPT_RT.
 
  - The last patch to remove the CONFIG_VIRT_TO_BUS option and
    some of the code behind that, after the last users of this
    old interface made it in through the netdev, scsi, media and
    staging trees.
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Merge tag 'asm-generic-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

Pull asm-generic updates from Arnd Bergmann:
 "There are three independent sets of changes:

   - Sai Prakash Ranjan adds tracing support to the asm-generic version
     of the MMIO accessors, which is intended to help understand
     problems with device drivers and has been part of Qualcomm's vendor
     kernels for many years

   - A patch from Sebastian Siewior to rework the handling of IRQ stacks
     in softirqs across architectures, which is needed for enabling
     PREEMPT_RT

   - The last patch to remove the CONFIG_VIRT_TO_BUS option and some of
     the code behind that, after the last users of this old interface
     made it in through the netdev, scsi, media and staging trees"

* tag 'asm-generic-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
  uapi: asm-generic: fcntl: Fix typo 'the the' in comment
  arch/*/: remove CONFIG_VIRT_TO_BUS
  soc: qcom: geni: Disable MMIO tracing for GENI SE
  serial: qcom_geni_serial: Disable MMIO tracing for geni serial
  asm-generic/io: Add logging support for MMIO accessors
  KVM: arm64: Add a flag to disable MMIO trace for nVHE KVM
  lib: Add register read/write tracing support
  drm/meson: Fix overflow implicit truncation warnings
  irqchip/tegra: Fix overflow implicit truncation warnings
  coresight: etm4x: Use asm-generic IO memory barriers
  arm64: io: Use asm-generic high level MMIO accessors
  arch/*: Disable softirq stacks on PREEMPT_RT.
2022-08-05 10:07:23 -07:00
Samuel Holland
073352e951 genirq: Add and use an irq_data_update_affinity helper
Some architectures and irqchip drivers modify the cpumask returned by
irq_data_get_affinity_mask, usually by copying in to it. This is
problematic for uniprocessor configurations, where the affinity mask
should be constant, as it is known at compile time.

Add and use a setter for the affinity mask, following the pattern of
irq_data_update_effective_affinity. This allows the getter function to
return a const cpumask pointer.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> # Xen bits
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220701200056.46555-7-samuel@sholland.org
2022-07-07 09:38:04 +01:00
Sebastian Andrzej Siewior
f2c5092190 arch/*: Disable softirq stacks on PREEMPT_RT.
PREEMPT_RT preempts softirqs and the current implementation avoids
do_softirq_own_stack() and only uses __do_softirq().

Disable the unused softirqs stacks on PREEMPT_RT to save some memory and
ensure that do_softirq_own_stack() is not used bwcause it is not expected.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-06-15 17:40:59 +02:00
Helge Deller
beb48dfd96 parisc: Move CPU startup-related functions into .text section
If CONFIG_HOTPLUG_CPU is enabled, those functions will be run again
after bootup. So they need to reside in the .text section.

Signed-off-by: Helge Deller <deller@gmx.de>
2022-03-29 21:37:12 +02:00
Helge Deller
ac2dd32794 parisc: Clean up cpu_check_affinity() and drop cpu_set_affinity_irq()
The cpu_set_affinity_irq() isn't needed. Not the CPU irqs need to
change, but the slave irq chips simply need to be reprogrammed to
a new CPU irq with the txn_* functions.

Signed-off-by: Helge Deller <deller@gmx.de>
2022-03-29 21:37:12 +02:00
Helge Deller
2214c0e772 parisc: Move thread_info into task struct
This implements the CONFIG_THREAD_INFO_IN_TASK option.

With this change:
- before thread_info was part of the stack and located at the beginning of the stack
- now the thread_info struct is moved and located inside the task_struct structure
- the stack is allocated and handled like the major other platforms
- drop the cpu field of thread_info and use instead the one in task_struct

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sven Schnelle <svens@stackframe.org>
2021-11-01 07:35:59 +01:00
Linus Torvalds
29c395c77a Rework of the X86 irq stack handling:
The irq stack switching was moved out of the ASM entry code in course of
   the entry code consolidation. It ended up being suboptimal in various
   ways.
 
   - Make the stack switching inline so the stackpointer manipulation is not
     longer at an easy to find place.
 
   - Get rid of the unnecessary indirect call.
 
   - Avoid the double stack switching in interrupt return and reuse the
     interrupt stack for softirq handling.
 
   - A objtool fix for CONFIG_FRAME_POINTER=y builds where it got confused
     about the stack pointer manipulation.
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Merge tag 'x86-entry-2021-02-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 irq entry updates from Thomas Gleixner:
 "The irq stack switching was moved out of the ASM entry code in course
  of the entry code consolidation. It ended up being suboptimal in
  various ways.

  This reworks the X86 irq stack handling:

   - Make the stack switching inline so the stackpointer manipulation is
     not longer at an easy to find place.

   - Get rid of the unnecessary indirect call.

   - Avoid the double stack switching in interrupt return and reuse the
     interrupt stack for softirq handling.

   - A objtool fix for CONFIG_FRAME_POINTER=y builds where it got
     confused about the stack pointer manipulation"

* tag 'x86-entry-2021-02-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Fix stack-swizzle for FRAME_POINTER=y
  um: Enforce the usage of asm-generic/softirq_stack.h
  x86/softirq/64: Inline do_softirq_own_stack()
  softirq: Move do_softirq_own_stack() to generic asm header
  softirq: Move __ARCH_HAS_DO_SOFTIRQ to Kconfig
  x86: Select CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK
  x86/softirq: Remove indirection in do_softirq_own_stack()
  x86/entry: Use run_sysvec_on_irqstack_cond() for XEN upcall
  x86/entry: Convert device interrupts to inline stack switching
  x86/entry: Convert system vectors to irq stack macro
  x86/irq: Provide macro for inlining irq stack switching
  x86/apic: Split out spurious handling code
  x86/irq/64: Adjust the per CPU irq stack pointer by 8
  x86/irq: Sanitize irq stack tracking
  x86/entry: Fix instrumentation annotation
2021-02-24 16:32:23 -08:00
John David Anglin
31680c1d15 parisc: Bump 64-bit IRQ stack size to 64 KB
Bump 64-bit IRQ stack size to 64 KB.

I had a kernel IRQ stack overflow on the mx3210 debian buildd machine.  This patch increases the
64-bit IRQ stack size to 64 KB.  The 64-bit stack size needs to be larger than the 32-bit stack
size since registers are twice as big.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
2021-02-12 16:31:51 +01:00
Thomas Gleixner
db1cc7aede softirq: Move do_softirq_own_stack() to generic asm header
To avoid include recursion hell move the do_softirq_own_stack() related
content into a generic asm header and include it from all places in arch/
which need the prototype.

This allows architectures to provide an inline implementation of
do_softirq_own_stack() without introducing a lot of #ifdeffery all over the
place.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210210002513.289960691@linutronix.de
2021-02-10 23:34:16 +01:00
Thomas Gleixner
7435248e6d parisc/irq: Use irq_desc_kstat_cpu() in show_interrupts()
The irq descriptor is already there, no need to look it up again.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-parisc@vger.kernel.org
Link: https://lore.kernel.org/r/20201210194043.659522455@linutronix.de
2020-12-15 16:19:31 +01:00
Thomas Gleixner
bb0e5192f5 parisc/irq: Simplify irq count output for /proc/interrupts
The SMP variant works perfectly fine on UP as well.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-parisc@vger.kernel.org
Link: https://lore.kernel.org/r/20201210194043.172893840@linutronix.de
2020-12-15 16:19:30 +01:00
afzal mohammed
997ba65736 parisc: Replace setup_irq() by request_irq()
request_irq() is preferred over setup_irq(). Invocations of setup_irq()
occur after memory allocators are ready.

Per tglx[1], setup_irq() existed in olden days when allocators were not
ready by the time early interrupts were initialized.

Hence replace setup_irq() by request_irq().

[1] https://lkml.kernel.org/r/alpine.DEB.2.20.1710191609480.1971@nanos

Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2020-04-05 22:05:23 +02:00
Thomas Gleixner
de6cc6515a treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 153
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 or at your option any
  later version this program is distributed in the hope that it will
  be useful but without any warranty without even the implied warranty
  of merchantability or fitness for a particular purpose see the gnu
  general public license for more details you should have received a
  copy of the gnu general public license along with this program if
  not write to the free software foundation inc 675 mass ave cambridge
  ma 02139 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 77 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.837555891@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Helge Deller
f73493eb4a parisc: Improve initial IRQ to CPU assignment
On parisc, each IRQ can only be handled by one CPU, and currently CPU0
is choosen as default for handling all IRQs by default.
With this patch we now assign each requested IRQ to one of the online
CPUs (and thus distribute the IRQs across all CPUs), even without an
instance of irqbalance running.

Signed-off-by: Helge Deller <deller@gmx.de>
2019-02-21 20:37:11 +01:00
Helge Deller
b102f29b2d parisc: Count IPI function call interrupts
Like other platforms, count the number of IPI function call interrupts
and show it in /proc/interrupts.

Signed-off-by: Helge Deller <deller@gmx.de>
2019-02-21 20:37:11 +01:00
Helge Deller
237a97d61e parisc: Show rescheduling interrupts on SMP machines only
Signed-off-by: Helge Deller <deller@gmx.de>
2019-02-21 20:37:11 +01:00
Helge Deller
8f8201dfed parisc: Increase thread and stack size to 32kb
Since kernel 4.11 the thread and irq stacks on parisc randomly overflow
the default size of 16k. The reason why stack usage suddenly grew is yet
unknown.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # 4.11+
Signed-off-by: Helge Deller <deller@gmx.de>
2017-07-31 08:41:26 +02:00
Helge Deller
5bc64bd246 parisc: Disable further stack checks when panic occurs during stack check
Before the irq handler detects a low stack and then panics the kernel, disable
further stack checks to avoid recursive panics.

Reported-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
2017-07-23 20:59:45 +02:00
Helge Deller
b1b4e435e4 parisc: Filter out spurious interrupts in PA-RISC irq handler
When detecting a serial port on newer PA-RISC machines (with iosapic) we have a
long way to go to find the right IRQ line, registering it, then registering the
serial port and the irq handler for the serial port. During this phase spurious
interrupts for the serial port may happen which then crashes the kernel because
the action handler might not have been set up yet.

So, basically it's a race condition between the serial port hardware and the
CPU which sets up the necessary fields in the irq sructs. The main reason for
this race is, that we unmask the serial port irqs too early without having set
up everything properly before (which isn't easily possible because we need the
IRQ number to register the serial ports).

This patch is a work-around for this problem. It adds checks to the CPU irq
handler to verify if the IRQ action field has been initialized already. If not,
we just skip this interrupt (which isn't critical for a serial port at bootup).
The real fix would probably involve rewriting all PA-RISC specific IRQ code
(for CPU, IOSAPIC, GSC and EISA) to use IRQ domains with proper parenting of
the irq chips and proper irq enabling along this line.

This bug has been in the PA-RISC port since the beginning, but the crashes
happened very rarely with currently used hardware.  But on the latest machine
which I bought (a C8000 workstation), which uses the fastest CPUs (4 x PA8900,
1GHz) and which has the largest possible L1 cache size (64MB each), the kernel
crashed at every boot because of this race. So, without this patch the machine
would currently be unuseable.

For the record, here is the flow logic:
1. serial_init_chip() in 8250_gsc.c calls iosapic_serial_irq().
2. iosapic_serial_irq() calls txn_alloc_irq() to find the irq.
3. iosapic_serial_irq() calls cpu_claim_irq() to register the CPU irq
4. cpu_claim_irq() unmasks the CPU irq (which it shouldn't!)
5. serial_init_chip() then registers the 8250 port.
Problems:
- In step 4 the CPU irq shouldn't have been registered yet, but after step 5
- If serial irq happens between 4 and 5 have finished, the kernel will crash

Signed-off-by: Helge Deller <deller@gmx.de>
2015-09-08 15:31:16 +02:00
Jiang Liu
d2109a1219 parisc/irq: Use access helper irq_data_get_affinity_mask()
Use access helper irq_data_get_affinity_mask() to hide implementation
details of struct irq_desc.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Link: http://lkml.kernel.org/r/1433145945-789-24-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-31 22:20:04 +02:00
Rusty Russell
409e56f3ef parisc: fix up obsolete cpu function usage.
Thanks to spatch.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
2015-03-05 15:25:08 +10:30
Thomas Gleixner
1ed71e59bc parisc: Validate online cpus in irq_set_affinity() callbacks
The [user space] interface does not filter out offline cpus. It merily
guarantees that the mask contains at least one online cpu.

So the selector in the irq chip implementation needs to make sure to
pick only an online cpu because otherwise:

     Offline Core 1
     Set affinity to 0xe (is valid due to online mask 0xd)
     cpumask_first will pick core 1, which is offline

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Link: http://lkml.kernel.org/r/20140304203100.859489993@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-03-12 13:07:41 +01:00
Linus Torvalds
1006fae359 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull IRQ changes from Ingo Molnar:
 "The biggest change this cycle are the softirq/hardirq stack
  interaction and nesting fixes, cleanups and reorganizations from
  Frederic.  This is the longer followup story to the softirq nesting
  fix that is already upstream (commit ded797547548: "irq: Force hardirq
  exit's softirq processing on its own stack")"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip: bcm2835: Convert to use IRQCHIP_DECLARE macro
  powerpc: Tell about irq stack coverage
  x86: Tell about irq stack coverage
  irq: Optimize softirq stack selection in irq exit
  irq: Justify the various softirq stack choices
  irq: Improve a bit softirq debugging
  irq: Optimize call to softirq on hardirq exit
  irq: Consolidate do_softirq() arch overriden implementations
  x86/irq: Correct comment about i8259 initialization
2013-11-12 10:02:59 +09:00
Helge Deller
6f0c4aa61d parisc: do not count IPI calls twice
The number of IPI calls is already visible as per-cpu IPI irq counters
in/proc/cpuinfo, so let's drop this additional counting.

This partly reverts:
cd85d55 parisc: more irq statistics in /proc/interrupts

Signed-off-by: Helge Deller <deller@gmx.de>
2013-11-07 22:28:54 +01:00
Frederic Weisbecker
7d65f4a655 irq: Consolidate do_softirq() arch overriden implementations
All arch overriden implementations of do_softirq() share the following
common code: disable irqs (to avoid races with the pending check),
check if there are softirqs pending, then execute __do_softirq() on
a specific stack.

Consolidate the common parts such that archs only worry about the
stack switch.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@au1.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@au1.ibm.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
2013-10-01 12:53:25 +02:00
Helge Deller
d96b51ec14 parisc: fix irq stack on UP and SMP
The logic to detect if the irq stack was already in use with
raw_spin_trylock() is wrong, because it will generate a "trylock failure
on UP" error message with CONFIG_SMP=n and CONFIG_DEBUG_SPINLOCK=y.

arch_spin_trylock() can't be used either since in the CONFIG_SMP=n case
no atomic protection is given and we are reentrant here. A mutex didn't
worked either and brings more overhead by turning off interrupts.

So, let's use the fastest path for parisc which is the ldcw instruction.

Counting how often the irq stack was used is pretty useless, so just
drop this piece of code.

Signed-off-by: Helge Deller <deller@gmx.de>
2013-05-24 23:29:01 +02:00
Helge Deller
d0c3be806a parisc: show number of FPE and unaligned access handler calls in /proc/interrupts
Show number of floating point assistant and unaligned access fixup
handler in /proc/interrupts file.

Signed-off-by: Helge Deller <deller@gmx.de>
2013-05-24 22:35:26 +02:00
Helge Deller
416821d3d6 parisc: implement irq stacks - part 2 (v2)
This patch fixes few build issues which were introduced with the last
irq stack patch, e.g. the combination of stack overflow check and irq
stack.

Furthermore we now do proper locking and change the irq bh handler
to use the irq stack as well.

In /proc/interrupts one now can monitor how huge the irq stack has grown
and how often it was preferred over the kernel stack.

IRQ stacks are now enabled by default just to make sure that we not
overflow the kernel stack by accident.

Signed-off-by: Helge Deller <deller@gmx.de>
2013-05-11 21:10:15 +02:00
Helge Deller
0fc537d1d6 parisc: tlb flush counting fix for SMP and UP
Fix up build error on UP and show correctly number of function call
(ipi) irqs.

Signed-off-by: Helge Deller <deller@gmx.de>
2013-05-07 23:44:04 +02:00
Helge Deller
cd85d5514d parisc: more irq statistics in /proc/interrupts
Add framework and initial values for more fine grained statistics in
/proc/interrupts.

Signed-off-by: Helge Deller <deller@gmx.de>
2013-05-07 22:39:22 +02:00
Helge Deller
200c880420 parisc: implement irq stacks
Default kernel stack size on parisc is 16k.  During tests we found that the
kernel stack can easily grow beyond 13k, which leaves 3k left for irq
processing.

This patch adds the possibility to activate an additional stack of 16k per CPU
which is being used during irq processing.  This implementation does not yet
uses this irq stack for the irq bh handler.

The assembler code for call_on_stack was heavily cleaned up by John
David Anglin.

CC: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
2013-05-07 22:30:35 +02:00
Helge Deller
9372450cc2 parisc: add kernel stack overflow check
Add the CONFIG_DEBUG_STACKOVERFLOW config option to enable checks to
detect kernel stack overflows.

Stack overflows can not be detected reliable since we do not want to
introduce too much overhead.

Instead, during irq processing in do_cpu_irq_mask() we check kernel
stack usage of the interrupted kernel process. Kernel threads can be
easily detected by checking the value of space register 7 (sr7) which
is zero when running inside the kernel.

Since THREAD_SIZE is 16k and PAGE_SIZE is 4k, reduce the alignment of
the init thread to the lower value (PAGE_SIZE) in the kernel
vmlinux.ld.S linker script.

Signed-off-by: Helge Deller <deller@gmx.de>
2013-05-07 21:34:07 +02:00
Peter Zijlstra
b54cb2332e parisc: remove IRQF_DISABLED
People are playing odd games with IRQF_DISABLED, remove it.

Its not reliable, since shared interrupt lines could disable it for you,
and its possible and allowed for archs to disable IRQs to limit IRQ nesting.

Therefore, simply mandate that _ALL_ IRQ handlers are run with IRQs disabled.

[ This _should_ not break anything, since we've mandated that IRQ handlers
  _must_ be able to deal with this for a _long_ time ]

IRQ handlers should be fast, no if buts and any other exceptions. We also have
plenty instrumentation to find any offending IRQ latency sources.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Helge Deller <deller@gmx.de>
2013-02-20 22:50:26 +01:00
John David Anglin
cac1f12b9f parisc: don't claim cpu irqs more than once
The CPU irqs (timer and IPI) are not shared and only need to be claimed once.
A mismatch error occurs if they are claimed more than once.

Signed-off-by: John David Anglin <dave.anglin@nrc-cnrc.gc.ca>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Signed-off-by: Helge Deller <deller@gmx.de>
2013-01-07 23:06:23 +01:00
Thomas Gleixner
68f20f43da parisc: Use irq_to_desc() in show_interrupts()
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-03-29 14:48:08 +02:00
Thomas Gleixner
e2f571d294 parisc: Convert irq namespace
Convert to the new function names. Scripted with coccinelle.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: linux-parisc@vger.kernel.org
2011-03-29 14:48:08 +02:00
Thomas Gleixner
337ce6811b parisc: Convert the final irq bits
1) As promised in the comment, the core does not copy cpumask anymore
   when the arch code returns -EINVAL

2) Get the per cpu information from irq_data

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: linux-parisc@vger.kernel.org
2011-03-29 14:48:08 +02:00
Thomas Gleixner
4c4231ea2f [PARISC] Convert to new irq_chip functions
Convert all the parisc driver interrupt handlers (dino, eisa, gsc,
iosapic and superio) as well as the cpu interrupts.  Prepare
show_interrupts for GENERIC_HARDIRQS_NO_DEPRECATED and finally selects
that Kconfig option

[jejb: compile and testing fixes]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-02-10 10:22:14 -06:00
Thomas Gleixner
9804c9eaea [PARISC] fix per-cpu flag problem in the cpu affinity checkers
The CHECK_IRQ_PER_CPU is wrong, it should be checking
irq_to_desc(irq)->status not just irq.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-02-09 13:06:07 -06:00
James Bottomley
51890613f2 parisc: convert the rest of the irq handlers to simple/percpu
The generic conversion eliminates the spurious no_ack and no_end
routines, converts all the cascaded handlers to handle_simple_irq() and
makes iosapic use a modified handle_percpu_irq() to become the same as
the CPU irq's.  This isn't an essential change, but it eliminates the
mask/unmask overhead of handle_level_irq().

Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Tested-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
2010-12-04 11:15:19 -05:00
James Bottomley
d16cd297d2 parisc: fix dino/gsc interrupts
The essential problem we're currently having is that dino (and gsc) is a
cascaded CPU interrupt.  Under the old __do_IRQ() handler, our CPU
interrupts basically did an ack followed by an end.  In the new scheme,
we replaced them with level handlers which do a mask, an ack and then an
unmask (but no end).  Instead, with the renaming of end to eoi, we
actually want to call the percpu flow handlers, because they actually
have all the characteristics we want.

This patch does the conversion and gets my C360 booting again.

Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
2010-12-04 11:14:32 -05:00
Kyle McMartin
7da1272547 parisc: kill __do_IRQ
Signed-off-by: Kyle McMartin <kyle@redhat.com>
2010-10-14 01:30:54 -04:00
Kyle McMartin
f3d4605977 parisc: convert iosapic interrupts to proper flow handlers
Shift the ->end call (cpu eoi) from __do_IRQ into our
unmask handler. Also nuke some redundant code.

Signed-off-by: Kyle McMartin <kyle@redhat.com>
2010-10-14 01:30:16 -04:00
Kyle McMartin
4d4f681dc4 parisc: convert cpu interrupts to proper flow handlers
Only major change is renaming functions to match the conventions
expected by the generic irq code.

Signed-off-by: Kyle McMartin <kyle@redhat.com>
2010-10-14 01:30:13 -04:00
Kyle McMartin
ba20085c20 parisc: lay groundwork for killing __do_IRQ
Use proper accessors and handlers for generic irq cleanups. We just
call back into __do_IRQ through desc->handler now, and remove the
explicit calls.

Signed-off-by: Kyle McMartin <kyle@redhat.com>
2010-10-14 01:30:11 -04:00
Thomas Gleixner
d0608b5474 parisc: Fixup last users of irq_chip->typename
The typename member of struct irq_chip was kept for migration purposes
and is obsolete since more than 2 years. Fix up the leftovers.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
2009-12-16 03:48:56 +00:00
Thomas Gleixner
239007b844 genirq: Convert irq_desc.lock to raw_spinlock
Convert locks which cannot be sleeping locks in preempt-rt to
raw_spinlocks.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
2009-12-14 23:55:33 +01:00