Commit Graph

222 Commits

Author SHA1 Message Date
Thomas Gleixner 6fd4e86125 tasklets: Switch tasklet_disable() to the sleep wait variant
-- NOT FOR IMMEDIATE MERGING --

Now that all users of tasklet_disable() are invoked from sleepable context,
convert it to use tasklet_unlock_wait() which might sleep.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210309084242.726452321@linutronix.de
2021-03-17 16:34:07 +01:00
Thomas Gleixner eb2dafbba8 tasklets: Prevent tasklet_unlock_spin_wait() deadlock on RT
tasklet_unlock_spin_wait() spin waits for the TASKLET_STATE_SCHED bit in
the tasklet state to be cleared. This works on !RT nicely because the
corresponding execution can only happen on a different CPU.

On RT softirq processing is preemptible, therefore a task preempting the
softirq processing thread can spin forever.

Prevent this by invoking local_bh_disable()/enable() inside the loop. In
case that the softirq processing thread was preempted by the current task,
current will block on the local lock which yields the CPU to the preempted
softirq processing thread. If the tasklet is processed on a different CPU
then the local_bh_disable()/enable() pair is just a waste of processor
cycles.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210309084241.988908275@linutronix.de
2021-03-17 16:33:57 +01:00
Peter Zijlstra da04474740 tasklets: Replace spin wait in tasklet_unlock_wait()
tasklet_unlock_wait() spin waits for TASKLET_STATE_RUN to be cleared. This
is wasting CPU cycles in a tight loop which is especially painful in a
guest when the CPU running the tasklet is scheduled out.

tasklet_unlock_wait() is invoked from tasklet_kill() which is used in
teardown paths and not performance critical at all. Replace the spin wait
with wait_var_event().

There are no users of tasklet_unlock_wait() which are invoked from atomic
contexts. The usage in tasklet_disable() has been replaced temporarily with
the spin waiting variant until the atomic users are fixed up and will be
converted to the sleep wait variant later.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210309084241.783936921@linutronix.de
2021-03-17 16:33:55 +01:00
Thomas Gleixner b0cd02c2a9 tasklets: Use spin wait in tasklet_disable() temporarily
To ease the transition use spin waiting in tasklet_disable() until all
usage sites from atomic context have been cleaned up.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210309084241.685352806@linutronix.de
2021-03-17 16:33:54 +01:00
Thomas Gleixner ca5f625118 tasklets: Provide tasklet_disable_in_atomic()
Replacing the spin wait loops in tasklet_unlock_wait() with
wait_var_event() is not possible as a handful of tasklet_disable()
invocations are happening in atomic context. All other invocations are in
teardown paths which can sleep.

Provide tasklet_disable_in_atomic() and tasklet_unlock_spin_wait() to
convert the few atomic use cases over, which allows to change
tasklet_disable() and tasklet_unlock_wait() in a later step.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210309084241.563164193@linutronix.de
2021-03-17 16:33:52 +01:00
Thomas Gleixner 6951547a13 tasklets: Use static inlines for stub implementations
Inlines exist for a reason.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210309084241.407702697@linutronix.de
2021-03-17 16:33:51 +01:00
Thomas Gleixner d2da74d127 tasklets: Replace barrier() with cpu_relax() in tasklet_unlock_wait()
A barrier() in a tight loop which waits for something to happen on a remote
CPU is a pointless exercise. Replace it with cpu_relax() which allows HT
siblings to make progress.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210309084241.249343366@linutronix.de
2021-03-17 16:33:51 +01:00
Davidlohr Bueso 3a0ade0c52 tasklet: Remove tasklet_kill_immediate
Ever since RCU was converted to softirq, it has no users.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20210306213658.12862-1-dave@stgolabs.net
2021-03-16 15:06:31 +01:00
Barry Song cbe16f35be genirq: Add IRQF_NO_AUTOEN for request_irq/nmi()
Many drivers don't want interrupts enabled automatically via request_irq().
So they are handling this issue by either way of the below two:

(1)
  irq_set_status_flags(irq, IRQ_NOAUTOEN);
  request_irq(dev, irq...);

(2)
  request_irq(dev, irq...);
  disable_irq(irq);

The code in the second way is silly and unsafe. In the small time gap
between request_irq() and disable_irq(), interrupts can still come.

The code in the first way is safe though it's subobtimal.

Add a new IRQF_NO_AUTOEN flag which can be handed in by drivers to
request_irq() and request_nmi(). It prevents the automatic enabling of the
requested interrupt/nmi in the same safe way as #1 above. With that the
various usage sites of #1 and #2 above can be simplified and corrected.

Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: dmitry.torokhov@gmail.com
Link: https://lore.kernel.org/r/20210302224916.13980-2-song.bao.hua@hisilicon.com
2021-03-06 12:48:00 +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 cd1a41ceba softirq: Move __ARCH_HAS_DO_SOFTIRQ to Kconfig
To prepare for inlining do_softirq_own_stack() replace
__ARCH_HAS_DO_SOFTIRQ with a Kconfig switch and select it in the affected
architectures.

This allows in the next step to move the function prototype and the inline
stub into a seperate asm-generic header file which is required to avoid
include recursion.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210210002513.181713427@linutronix.de
2021-02-10 23:34:16 +01:00
Thomas Gleixner a313357e70 genirq: Move irq_has_action() into core code
This function uses irq_to_desc() and is going to be used by modules to
replace the open coded irq_to_desc() (ab)usage. The final goal is to remove
the export of irq_to_desc() so driver cannot fiddle with it anymore.

Move it into the core code and fixup the usage sites to include the proper
header.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201210194042.548936472@linutronix.de
2020-12-15 16:19:30 +01:00
John Garry 1d3aec8928 genirq/affinity: Add irq_update_affinity_desc()
Add a function to allow the affinity of an interrupt be switched to
managed, such that interrupts allocated for platform devices may be
managed.

This new interface has certain limitations, and attempts to use it in the
following circumstances will fail:
- For when the kernel is configured for generic IRQ reservation mode (in
  config GENERIC_IRQ_RESERVATION_MODE). The reason being that it could
  conflict with managed vs. non-managed interrupt accounting.
- The interrupt is already started, which should not be the case during
  init
- The interrupt is already configured as managed, which means double init

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/1606905417-183214-2-git-send-email-john.garry@huawei.com
2020-12-11 14:47:50 +00:00
Joe Perches 33def8498f treewide: Convert macro and uses of __section(foo) to __section("foo")
Use a more generic form for __section that requires quotes to avoid
complications with clang and gcc differences.

Remove the quote operator # from compiler_attributes.h __section macro.

Convert all unquoted __section(foo) uses to quoted __section("foo").
Also convert __attribute__((section("foo"))) uses to __section("foo")
even if the __attribute__ has multiple list entry forms.

Conversion done using the script at:

    https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@gooogle.com>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-25 14:51:49 -07:00
Romain Perier 12cc923f1c tasklet: Introduce new initialization API
Nowadays, modern kernel subsystems that use callbacks pass the data
structure associated with a given callback as argument to the callback.
The tasklet subsystem remains one which passes an arbitrary unsigned
long to the callback function. This has several problems:

- This keeps an extra field for storing the argument in each tasklet
  data structure, it bloats the tasklet_struct structure with a redundant
  .data field

- No type checking can be performed on this argument. Instead of
  using container_of() like other callback subsystems, it forces callbacks
  to do explicit type cast of the unsigned long argument into the required
  object type.

- Buffer overflows can overwrite the .func and the .data field, so
  an attacker can easily overwrite the function and its first argument
  to whatever it wants.

Add a new tasklet initialization API, via DECLARE_TASKLET() and
tasklet_setup(), which will replace the existing ones.

This work is greatly inspired by the timer_struct conversion series,
see commit e99e88a9d2 ("treewide: setup_timer() -> timer_setup()")

To avoid problems with both -Wcast-function-type (which is enabled in
the kernel via -Wextra is several subsystems), and with mismatched
function prototypes when build with Control Flow Integrity enabled,
this adds the "use_callback" member to let the tasklet caller choose
which union member to call through. Once all old API uses are removed,
this and the .data member will be removed as well. (On 64-bit this does
not grow the struct size as the new member fills the hole after atomic_t,
which is also "int" sized.)

Signed-off-by: Romain Perier <romain.perier@gmail.com>
Co-developed-by: Allen Pais <allen.lkml@gmail.com>
Signed-off-by: Allen Pais <allen.lkml@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2020-07-30 11:16:01 -07:00
Kees Cook b13fecb1c3 treewide: Replace DECLARE_TASKLET() with DECLARE_TASKLET_OLD()
This converts all the existing DECLARE_TASKLET() (and ...DISABLED)
macros with DECLARE_TASKLET_OLD() in preparation for refactoring the
tasklet callback type. All existing DECLARE_TASKLET() users had a "0"
data argument, it has been removed here as well.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
2020-07-30 11:15:58 -07:00
Thomas Gleixner f0178fc01f x86/entry: Unbreak __irqentry_text_start/end magic
The entry rework moved interrupt entry code from the irqentry to the
noinstr section which made the irqentry section empty.

This breaks boundary checks which rely on the __irqentry_text_start/end
markers to find out whether a function in a stack trace is
interrupt/exception entry code. This affects the function graph tracer and
filter_irq_stacks().

As the IDT entry points are all sequentialy emitted this is rather simple
to unbreak by injecting __irqentry_text_start/end as global labels.

To make this work correctly:

  - Remove the IRQENTRY_TEXT section from the x86 linker script
  - Define __irqentry so it breaks the build if it's used
  - Adjust the entry mirroring in PTI
  - Remove the redundant kprobes and unwinder bound checks

Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2020-06-11 15:15:29 +02:00
Thomas Gleixner acd26bcf36 genirq: Provide interrupt injection mechanism
Error injection mechanisms need a half ways safe way to inject interrupts as
invoking generic_handle_irq() or the actual device interrupt handler
directly from e.g. a debugfs write is not guaranteed to be safe.

On x86 generic_handle_irq() is unsafe due to the hardware trainwreck which
is the base of x86 interrupt delivery and affinity management.

Move the irq debugfs injection code into a separate function which can be
used by error injection code as well.

The implementation prevents at least that state is corrupted, but it cannot
close a very tiny race window on x86 which might result in a stale and not
serviced device interrupt under very unlikely circumstances.

This is explicitly for debugging and testing and not for production use or
abuse in random driver code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lkml.kernel.org/r/20200306130623.990928309@linutronix.de
2020-03-08 11:06:42 +01:00
Linus Torvalds 043cf46825 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Ingo Molnar:
 "The main changes in the timer code in this cycle were:

   - Clockevent updates:

      - timer-of framework cleanups. (Geert Uytterhoeven)

      - Use timer-of for the renesas-ostm and the device name to prevent
        name collision in case of multiple timers. (Geert Uytterhoeven)

      - Check if there is an error after calling of_clk_get in asm9260
        (Chuhong Yuan)

   - ABI fix: Zero out high order bits of nanoseconds on compat
     syscalls. This got broken a year ago, with apparently no side
     effects so far.

     Since the kernel would use random data otherwise I don't think we'd
     have other options but to fix the bug, even if there was a side
     effect to applications (Dmitry Safonov)

   - Optimize ns_to_timespec64() on 32-bit systems: move away from
     div_s64_rem() which can be slow, to div_u64_rem() which is faster
     (Arnd Bergmann)

   - Annotate KCSAN-reported false positive data races in
     hrtimer_is_queued() users by moving timer->state handling over to
     the READ_ONCE()/WRITE_ONCE() APIs. This documents these accesses
     (Eric Dumazet)

   - Misc cleanups and small fixes"

[ I undid the "ABI fix" and updated the comments instead. The reason
  there were apparently no side effects is that the fix was a no-op.

  The updated comment is to say _why_ it was a no-op.    - Linus ]

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  time: Zero the upper 32-bits in __kernel_timespec on 32-bit
  time: Rename tsk->real_start_time to ->start_boottime
  hrtimer: Remove the comment about not used HRTIMER_SOFTIRQ
  time: Fix spelling mistake in comment
  time: Optimize ns_to_timespec64()
  hrtimer: Annotate lockless access to timer->state
  clocksource/drivers/asm9260: Add a check for of_clk_get
  clocksource/drivers/renesas-ostm: Use unique device name instead of ostm
  clocksource/drivers/renesas-ostm: Convert to timer_of
  clocksource/drivers/timer-of: Use unique device name instead of timer
  clocksource/drivers/timer-of: Convert last full_name to %pOF
2019-12-03 12:20:25 -08:00
Jonathan Corbet 5ca470a0c3 docs: Add request_irq() documentation
While checking the results of the :c:func: removal, I noticed that there
was no documentation for request_irq(), and request_threaded_irq() was not
mentioned at all.  Add a kerneldoc comment for request_irq() and add
request_threaded_irq() to the list of functions.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-11-18 12:40:59 -07:00
Sebastian Andrzej Siewior 3bbc53f4ae hrtimer: Remove the comment about not used HRTIMER_SOFTIRQ
The softirq `HRTIMER_SOFTIRQ' was not used since commit c6eb3f70d4
("hrtimer: Get rid of hrtimer softirq").

But it got used again, beginning with commit 5da7016046 ("hrtimer:
Implement support for softirq based hrtimers"), which did not remove the
comment. Remove it now.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191107091924.13410-1-bigeasy@linutronix.de
2019-11-12 16:15:57 +01:00
Linus Torvalds 77dcfe2b9e Power management updates for 5.4-rc1
- Rework the main suspend-to-idle control flow to avoid repeating
    "noirq" device resume and suspend operations in case of spurious
    wakeups from the ACPI EC and decouple the ACPI EC wakeups support
    from the LPS0 _DSM support (Rafael Wysocki).
 
  - Extend the wakeup sources framework to expose wakeup sources as
    device objects in sysfs (Tri Vo, Stephen Boyd).
 
  - Expose system suspend statistics in sysfs (Kalesh Singh).
 
  - Introduce a new haltpoll cpuidle driver and a new matching
    governor for virtualized guests wanting to do guest-side polling
    in the idle loop (Marcelo Tosatti, Joao Martins, Wanpeng Li,
    Stephen Rothwell).
 
  - Fix the menu and teo cpuidle governors to allow the scheduler tick
    to be stopped if PM QoS is used to limit the CPU idle state exit
    latency in some cases (Rafael Wysocki).
 
  - Increase the resolution of the play_idle() argument to microseconds
    for more fine-grained injection of CPU idle cycles (Daniel Lezcano).
 
  - Switch over some users of cpuidle notifiers to the new QoS-based
    frequency limits and drop the CPUFREQ_ADJUST and CPUFREQ_NOTIFY
    policy notifier events (Viresh Kumar).
 
  - Add new cpufreq driver based on nvmem for sun50i (Yangtao Li).
 
  - Add support for MT8183 and MT8516 to the mediatek cpufreq driver
    (Andrew-sh.Cheng, Fabien Parent).
 
  - Add i.MX8MN support to the imx-cpufreq-dt cpufreq driver (Anson
    Huang).
 
  - Add qcs404 to cpufreq-dt-platdev blacklist (Jorge Ramirez-Ortiz).
 
  - Update the qcom cpufreq driver (among other things, to make it
    easier to extend and to use kryo cpufreq for other nvmem-based
    SoCs) and add qcs404 support to it  (Niklas Cassel, Douglas
    RAILLARD, Sibi Sankar, Sricharan R).
 
  - Fix assorted issues and make assorted minor improvements in the
    cpufreq code (Colin Ian King, Douglas RAILLARD, Florian Fainelli,
    Gustavo Silva, Hariprasad Kelam).
 
  - Add new devfreq driver for NVidia Tegra20 (Dmitry Osipenko, Arnd
    Bergmann).
 
  - Add new Exynos PPMU events to devfreq events and extend that
    mechanism (Lukasz Luba).
 
  - Fix and clean up the exynos-bus devfreq driver (Kamil Konieczny).
 
  - Improve devfreq documentation and governor code, fix spelling
    typos in devfreq (Ezequiel Garcia, Krzysztof Kozlowski, Leonard
    Crestez, MyungJoo Ham, Gaël PORTAY).
 
  - Add regulators enable and disable to the OPP (operating performance
    points) framework (Kamil Konieczny).
 
  - Update the OPP framework to support multiple opp-suspend properties
    (Anson Huang).
 
  - Fix assorted issues and make assorted minor improvements in the OPP
    code (Niklas Cassel, Viresh Kumar, Yue Hu).
 
  - Clean up the generic power domains (genpd) framework (Ulf Hansson).
 
  - Clean up assorted pieces of power management code and documentation
    (Akinobu Mita, Amit Kucheria, Chuhong Yuan).
 
  - Update the pm-graph tool to version 5.5 including multiple fixes
    and improvements (Todd Brandt).
 
  - Update the cpupower utility (Benjamin Weis, Geert Uytterhoeven,
    Sébastien Szymanski).
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Merge tag 'pm-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "These include a rework of the main suspend-to-idle code flow (related
  to the handling of spurious wakeups), a switch over of several users
  of cpufreq notifiers to QoS-based limits, a new devfreq driver for
  Tegra20, a new cpuidle driver and governor for virtualized guests, an
  extension of the wakeup sources framework to expose wakeup sources as
  device objects in sysfs, and more.

  Specifics:

   - Rework the main suspend-to-idle control flow to avoid repeating
     "noirq" device resume and suspend operations in case of spurious
     wakeups from the ACPI EC and decouple the ACPI EC wakeups support
     from the LPS0 _DSM support (Rafael Wysocki).

   - Extend the wakeup sources framework to expose wakeup sources as
     device objects in sysfs (Tri Vo, Stephen Boyd).

   - Expose system suspend statistics in sysfs (Kalesh Singh).

   - Introduce a new haltpoll cpuidle driver and a new matching governor
     for virtualized guests wanting to do guest-side polling in the idle
     loop (Marcelo Tosatti, Joao Martins, Wanpeng Li, Stephen Rothwell).

   - Fix the menu and teo cpuidle governors to allow the scheduler tick
     to be stopped if PM QoS is used to limit the CPU idle state exit
     latency in some cases (Rafael Wysocki).

   - Increase the resolution of the play_idle() argument to microseconds
     for more fine-grained injection of CPU idle cycles (Daniel
     Lezcano).

   - Switch over some users of cpuidle notifiers to the new QoS-based
     frequency limits and drop the CPUFREQ_ADJUST and CPUFREQ_NOTIFY
     policy notifier events (Viresh Kumar).

   - Add new cpufreq driver based on nvmem for sun50i (Yangtao Li).

   - Add support for MT8183 and MT8516 to the mediatek cpufreq driver
     (Andrew-sh.Cheng, Fabien Parent).

   - Add i.MX8MN support to the imx-cpufreq-dt cpufreq driver (Anson
     Huang).

   - Add qcs404 to cpufreq-dt-platdev blacklist (Jorge Ramirez-Ortiz).

   - Update the qcom cpufreq driver (among other things, to make it
     easier to extend and to use kryo cpufreq for other nvmem-based
     SoCs) and add qcs404 support to it (Niklas Cassel, Douglas
     RAILLARD, Sibi Sankar, Sricharan R).

   - Fix assorted issues and make assorted minor improvements in the
     cpufreq code (Colin Ian King, Douglas RAILLARD, Florian Fainelli,
     Gustavo Silva, Hariprasad Kelam).

   - Add new devfreq driver for NVidia Tegra20 (Dmitry Osipenko, Arnd
     Bergmann).

   - Add new Exynos PPMU events to devfreq events and extend that
     mechanism (Lukasz Luba).

   - Fix and clean up the exynos-bus devfreq driver (Kamil Konieczny).

   - Improve devfreq documentation and governor code, fix spelling typos
     in devfreq (Ezequiel Garcia, Krzysztof Kozlowski, Leonard Crestez,
     MyungJoo Ham, Gaël PORTAY).

   - Add regulators enable and disable to the OPP (operating performance
     points) framework (Kamil Konieczny).

   - Update the OPP framework to support multiple opp-suspend properties
     (Anson Huang).

   - Fix assorted issues and make assorted minor improvements in the OPP
     code (Niklas Cassel, Viresh Kumar, Yue Hu).

   - Clean up the generic power domains (genpd) framework (Ulf Hansson).

   - Clean up assorted pieces of power management code and documentation
     (Akinobu Mita, Amit Kucheria, Chuhong Yuan).

   - Update the pm-graph tool to version 5.5 including multiple fixes
     and improvements (Todd Brandt).

   - Update the cpupower utility (Benjamin Weis, Geert Uytterhoeven,
     Sébastien Szymanski)"

* tag 'pm-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (126 commits)
  cpuidle-haltpoll: Enable kvm guest polling when dedicated physical CPUs are available
  cpuidle-haltpoll: do not set an owner to allow modunload
  cpuidle-haltpoll: return -ENODEV on modinit failure
  cpuidle-haltpoll: set haltpoll as preferred governor
  cpuidle: allow governor switch on cpuidle_register_driver()
  PM: runtime: Documentation: add runtime_status ABI document
  pm-graph: make setVal unbuffered again for python2 and python3
  powercap: idle_inject: Use higher resolution for idle injection
  cpuidle: play_idle: Increase the resolution to usec
  cpuidle-haltpoll: vcpu hotplug support
  cpufreq: Add qcs404 to cpufreq-dt-platdev blacklist
  cpufreq: qcom: Add support for qcs404 on nvmem driver
  cpufreq: qcom: Refactor the driver to make it easier to extend
  cpufreq: qcom: Re-organise kryo cpufreq to use it for other nvmem based qcom socs
  dt-bindings: opp: Add qcom-opp bindings with properties needed for CPR
  dt-bindings: opp: qcom-nvmem: Support pstates provided by a power domain
  Documentation: cpufreq: Update policy notifier documentation
  cpufreq: Remove CPUFREQ_ADJUST and CPUFREQ_NOTIFY policy notifier events
  PM / Domains: Verify PM domain type in dev_pm_genpd_set_performance_state()
  PM / Domains: Simplify genpd_lookup_dev()
  ...
2019-09-17 19:15:14 -07:00
Thomas Gleixner b6a32bbd87 genirq: Force interrupt threading on RT
Switch force_irqthreads from a boot time modifiable variable to a compile
time constant when CONFIG_PREEMPT_RT is enabled.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190816160923.12855-1-bigeasy@linutronix.de
2019-08-19 15:45:48 +02:00
Rafael J. Wysocki 3a79bc63d9 PCI: irq: Introduce rearm_wake_irq()
Introduce a new function, rearm_wake_irq(), allowing a wakeup IRQ
to be armed for systen wakeup detection again without running any
action handlers associated with it after it has been armed for
wakeup detection and triggered.

That is useful for IRQs, like ACPI SCI, that may deliver wakeup
as well as non-wakeup interrupts when armed for systen wakeup
detection.  In those cases, it may be possible to determine whether
or not the delivered interrupt is a systen wakeup one without
running the entire action handler (or handlers, if the IRQ is
shared) for the IRQ, and if the interrupt turns out to be a
non-wakeup one, the IRQ can be rearmed with the help of the
new function.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
2019-07-23 09:37:51 +02:00
Mauro Carvalho Chehab 151f4e2bdc docs: power: convert docs to ReST and rename to *.rst
Convert the PM documents to ReST, in order to allow them to
build with Sphinx.

The conversion is actually:
  - add blank lines and indentation in order to identify paragraphs;
  - fix tables markups;
  - add some lists markups;
  - mark literal blocks;
  - adjust title markups.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
2019-06-14 16:08:36 -05:00
Thomas Gleixner d7dcf26ff0 softirq: Remove tasklet_hrtimer
There are no more users of this interface.
Remove it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Link: https://lkml.kernel.org/r/20190301224821.29843-4-bigeasy@linutronix.de
2019-03-22 14:36:02 +01:00
Thomas Gleixner a324ca9cad irqchip updates for Linux 5.1
- Core pseudo-NMI handling code
 - Allow the default irq domain to be retrieved
 - A new interrupt controller for the Loongson LS1X platform
 - Affinity support for the SiFive PLIC
 - Better support for the iMX irqsteer driver
 - NUMA aware memory allocations for GICv3
 - A handful of other fixes (i8259, GICv3, PLIC)
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Merge tag 'irqchip-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core

Pull irqchip updates from Marc Zyngier

- Core pseudo-NMI handling code
- Allow the default irq domain to be retrieved
- A new interrupt controller for the Loongson LS1X platform
- Affinity support for the SiFive PLIC
- Better support for the iMX irqsteer driver
- NUMA aware memory allocations for GICv3
- A handful of other fixes (i8259, GICv3, PLIC)
2019-02-23 10:53:31 +01:00
Ming Lei c66d4bd110 genirq/affinity: Add new callback for (re)calculating interrupt sets
The interrupt affinity spreading mechanism supports to spread out
affinities for one or more interrupt sets. A interrupt set contains one or
more interrupts. Each set is mapped to a specific functionality of a
device, e.g. general I/O queues and read I/O queus of multiqueue block
devices.

The number of interrupts per set is defined by the driver. It depends on
the total number of available interrupts for the device, which is
determined by the PCI capabilites and the availability of underlying CPU
resources, and the number of queues which the device provides and the
driver wants to instantiate.

The driver passes initial configuration for the interrupt allocation via a
pointer to struct irq_affinity.

Right now the allocation mechanism is complex as it requires to have a loop
in the driver to determine the maximum number of interrupts which are
provided by the PCI capabilities and the underlying CPU resources.  This
loop would have to be replicated in every driver which wants to utilize
this mechanism. That's unwanted code duplication and error prone.

In order to move this into generic facilities it is required to have a
mechanism, which allows the recalculation of the interrupt sets and their
size, in the core code. As the core code does not have any knowledge about the
underlying device, a driver specific callback is required in struct
irq_affinity, which can be invoked by the core code. The callback gets the
number of available interupts as an argument, so the driver can calculate the
corresponding number and size of interrupt sets.

At the moment the struct irq_affinity pointer which is handed in from the
driver and passed through to several core functions is marked 'const', but for
the callback to be able to modify the data in the struct it's required to
remove the 'const' qualifier.

Add the optional callback to struct irq_affinity, which allows drivers to
recalculate the number and size of interrupt sets and remove the 'const'
qualifier.

For simple invocations, which do not supply a callback, a default callback
is installed, which just sets nr_sets to 1 and transfers the number of
spreadable vectors to the set_size array at index 0.

This is for now guarded by a check for nr_sets != 0 to keep the NVME driver
working until it is converted to the callback mechanism.

To make sure that the driver configuration is correct under all circumstances
the callback is invoked even when there are no interrupts for queues left,
i.e. the pre/post requirements already exhaust the numner of available
interrupts.

At the PCI layer irq_create_affinity_masks() has to be invoked even for the
case where the legacy interrupt is used. That ensures that the callback is
invoked and the device driver can adjust to that situation.

[ tglx: Fixed the simple case (no sets required). Moved the sanity check
  	for nr_sets after the invocation of the callback so it catches
  	broken drivers. Fixed the kernel doc comments for struct
  	irq_affinity and de-'This patch'-ed the changelog ]

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Bjorn Helgaas <helgaas@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: linux-nvme@lists.infradead.org
Cc: linux-pci@vger.kernel.org
Cc: Keith Busch <keith.busch@intel.com>
Cc: Sumit Saxena <sumit.saxena@broadcom.com>
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Shivasharan Srikanteshwara <shivasharan.srikanteshwara@broadcom.com>
Link: https://lkml.kernel.org/r/20190216172228.512444498@linutronix.de
2019-02-18 11:21:28 +01:00
Ming Lei 9cfef55bb5 genirq/affinity: Store interrupt sets size in struct irq_affinity
The interrupt affinity spreading mechanism supports to spread out
affinities for one or more interrupt sets. A interrupt set contains one
or more interrupts. Each set is mapped to a specific functionality of a
device, e.g. general I/O queues and read I/O queus of multiqueue block
devices.

The number of interrupts per set is defined by the driver. It depends on
the total number of available interrupts for the device, which is
determined by the PCI capabilites and the availability of underlying CPU
resources, and the number of queues which the device provides and the
driver wants to instantiate.

The driver passes initial configuration for the interrupt allocation via
a pointer to struct irq_affinity.

Right now the allocation mechanism is complex as it requires to have a
loop in the driver to determine the maximum number of interrupts which
are provided by the PCI capabilities and the underlying CPU resources.
This loop would have to be replicated in every driver which wants to
utilize this mechanism. That's unwanted code duplication and error
prone.

In order to move this into generic facilities it is required to have a
mechanism, which allows the recalculation of the interrupt sets and
their size, in the core code. As the core code does not have any
knowledge about the underlying device, a driver specific callback will
be added to struct affinity_desc, which will be invoked by the core
code. The callback will get the number of available interupts as an
argument, so the driver can calculate the corresponding number and size
of interrupt sets.

To support this, two modifications for the handling of struct irq_affinity
are required:

1) The (optional) interrupt sets size information is contained in a
   separate array of integers and struct irq_affinity contains a
   pointer to it.

   This is cumbersome and as the maximum number of interrupt sets is small,
   there is no reason to have separate storage. Moving the size array into
   struct affinity_desc avoids indirections and makes the code simpler.

2) At the moment the struct irq_affinity pointer which is handed in from
   the driver and passed through to several core functions is marked
   'const'.

   With the upcoming callback to recalculate the number and size of
   interrupt sets, it's necessary to remove the 'const'
   qualifier. Otherwise the callback would not be able to update the data.

Implement #1 and store the interrupt sets size in 'struct irq_affinity'.

No functional change.

[ tglx: Fixed the memcpy() size so it won't copy beyond the size of the
  	source. Fixed the kernel doc comments for struct irq_affinity and
  	de-'This patch'-ed the changelog ]

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Bjorn Helgaas <helgaas@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: linux-nvme@lists.infradead.org
Cc: linux-pci@vger.kernel.org
Cc: Keith Busch <keith.busch@intel.com>
Cc: Sumit Saxena <sumit.saxena@broadcom.com>
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Shivasharan Srikanteshwara <shivasharan.srikanteshwara@broadcom.com>
Link: https://lkml.kernel.org/r/20190216172228.423723127@linutronix.de
2019-02-18 11:21:27 +01:00
Thomas Gleixner 0145c30e89 genirq/affinity: Code consolidation
All information and calculations in the interrupt affinity spreading code
is strictly unsigned int. Though the code uses int all over the place.

Convert it over to unsigned int.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Bjorn Helgaas <helgaas@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: linux-nvme@lists.infradead.org
Cc: linux-pci@vger.kernel.org
Cc: Keith Busch <keith.busch@intel.com>
Cc: Sumit Saxena <sumit.saxena@broadcom.com>
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Shivasharan Srikanteshwara <shivasharan.srikanteshwara@broadcom.com>
Link: https://lkml.kernel.org/r/20190216172228.336424556@linutronix.de
2019-02-18 11:21:27 +01:00
Julien Thierry 4b078c3f1a genirq: Provide NMI management for percpu_devid interrupts
Add support for percpu_devid interrupts treated as NMIs.

Percpu_devid NMIs need to be setup/torn down on each CPU they target.

The same restrictions as for global NMIs still apply for percpu_devid NMIs.

Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-02-05 14:36:58 +00:00
Julien Thierry b525903c25 genirq: Provide basic NMI management for interrupt lines
Add functionality to allocate interrupt lines that will deliver IRQs
as Non-Maskable Interrupts. These allocations are only successful if
the irqchip provides the necessary support and allows NMI delivery for the
interrupt line.

Interrupt lines allocated for NMI delivery must be enabled/disabled through
enable_nmi/disable_nmi_nosync to keep their state consistent.

To treat a PERCPU IRQ as NMI, the interrupt must not be shared nor threaded,
the irqchip directly managing the IRQ must be the root irqchip and the
irqchip cannot be behind a slow bus.

Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-02-05 14:36:57 +00:00
Jonathan Corbet 70921ae25f genirq: Fix the kerneldoc comment for struct irq_affinity_desc
A recent commit added a new field but did not update the kerneldoc comment,
leading to this build warning:

  ./include/linux/interrupt.h:268: warning: Function parameter or member 'is_managed' not described in 'irq_affinity_desc'

Add the missing information, making the docs build 0.001% quieter.

Fixes: c410abbbac ("genirq/affinity: Add is_managed to struct irq_affinity_desc")
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dou Liyang <douliyangs@gmail.com>
Link: https://lkml.kernel.org/r/20190108170432.59bae8a6@lwn.net
2019-01-18 00:18:45 +01:00
Dou Liyang c410abbbac genirq/affinity: Add is_managed to struct irq_affinity_desc
Devices which use managed interrupts usually have two classes of
interrupts:

  - Interrupts for multiple device queues
  - Interrupts for general device management

Currently both classes are treated the same way, i.e. as managed
interrupts. The general interrupts get the default affinity mask assigned
while the device queue interrupts are spread out over the possible CPUs.

Treating the general interrupts as managed is both a limitation and under
certain circumstances a bug. Assume the following situation:

 default_irq_affinity = 4..7

So if CPUs 4-7 are offlined, then the core code will shut down the device
management interrupts because the last CPU in their affinity mask went
offline.

It's also a limitation because it's desired to allow manual placement of
the general device interrupts for various reasons. If they are marked
managed then the interrupt affinity setting from both user and kernel space
is disabled. That limitation was reported by Kashyap and Sumit.

Expand struct irq_affinity_desc with a new bit 'is_managed' which is set
for truly managed interrupts (queue interrupts) and cleared for the general
device interrupts.

[ tglx: Simplify code and massage changelog ]

Reported-by: Kashyap Desai <kashyap.desai@broadcom.com>
Reported-by: Sumit Saxena <sumit.saxena@broadcom.com>
Signed-off-by: Dou Liyang <douliyangs@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-pci@vger.kernel.org
Cc: shivasharan.srikanteshwara@broadcom.com
Cc: ming.lei@redhat.com
Cc: hch@lst.de
Cc: bhelgaas@google.com
Cc: douliyang1@huawei.com
Link: https://lkml.kernel.org/r/20181204155122.6327-3-douliyangs@gmail.com
2018-12-19 11:32:08 +01:00
Dou Liyang bec04037e4 genirq/core: Introduce struct irq_affinity_desc
The interrupt affinity management uses straight cpumask pointers to convey
the automatically assigned affinity masks for managed interrupts. The core
interrupt descriptor allocation also decides based on the pointer being non
NULL whether an interrupt is managed or not.

Devices which use managed interrupts usually have two classes of
interrupts:

  - Interrupts for multiple device queues
  - Interrupts for general device management

Currently both classes are treated the same way, i.e. as managed
interrupts. The general interrupts get the default affinity mask assigned
while the device queue interrupts are spread out over the possible CPUs.

Treating the general interrupts as managed is both a limitation and under
certain circumstances a bug. Assume the following situation:

 default_irq_affinity = 4..7

So if CPUs 4-7 are offlined, then the core code will shut down the device
management interrupts because the last CPU in their affinity mask went
offline.

It's also a limitation because it's desired to allow manual placement of
the general device interrupts for various reasons. If they are marked
managed then the interrupt affinity setting from both user and kernel space
is disabled.

To remedy that situation it's required to convey more information than the
cpumasks through various interfaces related to interrupt descriptor
allocation.

Instead of adding yet another argument, create a new data structure
'irq_affinity_desc' which for now just contains the cpumask. This struct
can be expanded to convey auxilliary information in the next step.

No functional change, just preparatory work.

[ tglx: Simplified logic and clarified changelog ]

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Dou Liyang <douliyangs@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-pci@vger.kernel.org
Cc: kashyap.desai@broadcom.com
Cc: shivasharan.srikanteshwara@broadcom.com
Cc: sumit.saxena@broadcom.com
Cc: ming.lei@redhat.com
Cc: hch@lst.de
Cc: douliyang1@huawei.com
Link: https://lkml.kernel.org/r/20181204155122.6327-2-douliyangs@gmail.com
2018-12-19 11:32:08 +01:00
Jens Axboe 6da4b3ab9a genirq/affinity: Add support for allocating interrupt sets
A driver may have a need to allocate multiple sets of MSI/MSI-X interrupts,
and have them appropriately affinitized.

Add support for defining a number of sets in the irq_affinity structure, of
varying sizes, and get each set affinitized correctly across the machine.

[ tglx: Minor changelog tweaks ]

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Cc: linux-block@vger.kernel.org
Link: https://lkml.kernel.org/r/20181102145951.31979-5-ming.lei@redhat.com
2018-11-05 12:16:27 +01:00
Geert Uytterhoeven b8d62f33b7 genirq: Fix grammar s/an /a /
Fix a grammar mistake in <linux/interrupt.h>.

[ mingo: While at it also fix another similar error in another comment as well. ]

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Jiri Kosina <trivial@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20181008111726.26286-1-geert%2Brenesas@glider.be
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-09 07:50:41 +02:00
Frederic Weisbecker 48bda43eab softirq/s390: Move default mutators of overwritten softirq mask to s390
s390 is now the last architecture that entirely overwrites
local_softirq_pending() and uses the according default definitions of
set_softirq_pending() and or_softirq_pending().

Just move these to s390 to debloat the generic code complexity.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/1525786706-22846-12-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-14 11:25:28 +02:00
Frederic Weisbecker 0fd7d86285 softirq/core: Consolidate default local_softirq_pending() implementations
Consolidate and optimize default softirq mask API implementations.
Per-CPU operations are expected to be faster and a few architectures
already rely on them to implement local_softirq_pending() and related
accessors/mutators. Those will be migrated to the new generic code.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/1525786706-22846-6-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-14 11:25:27 +02:00
Randy Dunlap 562c45d635 headers: Drop two #included headers from <linux/interrupt.h>
It seems that <linux/interrupt.h> does not need <linux/linkage.h>
nor <linux/preempt.h>.  8 kernels builds are successful without
these 2 headers (allmodconfig, allyesconfig, allnoconfig, and
tinyconfig on both i386 and x86_64).

<linux/interrupt.h> is #included 3875 times in 4.16-rc1, so this
reduces #include processing of these 2 files by a total of 7750 times.

Since I only tested x86 builds, this needs to be tested on other
$ARCHes as well.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Link: http://lkml.kernel.org/r/b24b9ec8-4970-65f5-759a-911d4ba2fcf0@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-16 08:59:16 +01:00
Levin, Alexander (Sasha Levin) 4675ff05de kmemcheck: rip it out
Fix up makefiles, remove references, and git rm kmemcheck.

Link: http://lkml.kernel.org/r/20171007030159.22241-4-alexander.levin@verizon.com
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Vegard Nossum <vegardno@ifi.uio.no>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Tim Hansen <devtimhansen@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:05 -08:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Masami Hiramatsu 229a718605 irq: Make the irqentry text section unconditional
Generate irqentry and softirqentry text sections without
any Kconfig dependencies. This will add extra sections, but
there should be no performace impact.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David S . Miller <davem@davemloft.net>
Cc: Francis Deslauriers <francis.deslauriers@efficios.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: linux-arch@vger.kernel.org
Cc: linux-cris-kernel@axis.com
Cc: mathieu.desnoyers@efficios.com
Link: http://lkml.kernel.org/r/150172789110.27216.3955739126693102122.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10 16:28:53 +02:00
Linus Torvalds 7cb328c30a Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:

 - A few fixes mopping up the fallout of the big irq overhaul

 - Move the interrupt resource management logic out of the spin locked,
   irq disabled region to avoid unnecessary restrictions of the resource
   callbacks

 - Preparation for reworking the per cpu irq request function.

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqdomain: Allow ACPI device nodes to be used as irqdomain identifiers
  genirq/debugfs: Remove redundant NULL pointer check
  genirq: Allow to pass the IRQF_TIMER flag with percpu irq request
  genirq/timings: Move free timings out of spinlocked region
  genirq: Move irq resource handling out of spinlocked region
  genirq: Add mutex to irq desc to serialize request/free_irq()
  genirq: Move bus locking into __setup_irq()
  genirq: Force inlining of __irq_startup_managed to prevent build failure
  genirq/debugfs: Fix build for !CONFIG_IRQ_DOMAIN
2017-07-09 10:24:46 -07:00
Linus Torvalds f263fbb8d6 pci-v4.13-changes
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Merge tag 'pci-v4.13-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI updates from Bjorn Helgaas:

  - add sysfs max_link_speed/width, current_link_speed/width (Wong Vee
    Khee)

  - make host bridge IRQ mapping much more generic (Matthew Minter,
    Lorenzo Pieralisi)

  - convert most drivers to pci_scan_root_bus_bridge() (Lorenzo
    Pieralisi)

  - mutex sriov_configure() (Jakub Kicinski)

  - mutex pci_error_handlers callbacks (Christoph Hellwig)

  - split ->reset_notify() into ->reset_prepare()/reset_done()
    (Christoph Hellwig)

  - support multiple PCIe portdrv interrupts for MSI as well as MSI-X
    (Gabriele Paoloni)

  - allocate MSI/MSI-X vector for Downstream Port Containment (Gabriele
    Paoloni)

  - fix MSI IRQ affinity pre/post/min_vecs issue (Michael Hernandez)

  - test INTx masking during enumeration, not at run-time (Piotr Gregor)

  - avoid using device_may_wakeup() for runtime PM (Rafael J. Wysocki)

  - restore the status of PCI devices across hibernation (Chen Yu)

  - keep parent resources that start at 0x0 (Ard Biesheuvel)

  - enable ECRC only if device supports it (Bjorn Helgaas)

  - restore PRI and PASID state after Function-Level Reset (CQ Tang)

  - skip DPC event if device is not present (Keith Busch)

  - check domain when matching SMBIOS info (Sujith Pandel)

  - mark Intel XXV710 NIC INTx masking as broken (Alex Williamson)

  - avoid AMD SB7xx EHCI USB wakeup defect (Kai-Heng Feng)

  - work around long-standing Macbook Pro poweroff issue (Bjorn Helgaas)

  - add Switchtec "running" status flag (Logan Gunthorpe)

  - fix dra7xx incorrect RW1C IRQ register usage (Arvind Yadav)

  - modify xilinx-nwl IRQ chip for legacy interrupts (Bharat Kumar
    Gogada)

  - move VMD SRCU cleanup after bus, child device removal (Jon Derrick)

  - add Faraday clock handling (Linus Walleij)

  - configure Rockchip MPS and reorganize (Shawn Lin)

  - limit Qualcomm TLP size to 2K (hardware issue) (Srinivas Kandagatla)

  - support Tegra MSI 64-bit addressing (Thierry Reding)

  - use Rockchip normal (not privileged) register bank (Shawn Lin)

  - add HiSilicon Kirin SoC PCIe controller driver (Xiaowei Song)

  - add Sigma Designs Tango SMP8759 PCIe controller driver (Marc
    Gonzalez)

  - add MediaTek PCIe host controller support (Ryder Lee)

  - add Qualcomm IPQ4019 support (John Crispin)

  - add HyperV vPCI protocol v1.2 support (Jork Loeser)

  - add i.MX6 regulator support (Quentin Schulz)

* tag 'pci-v4.13-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (113 commits)
  PCI: tango: Add Sigma Designs Tango SMP8759 PCIe host bridge support
  PCI: Add DT binding for Sigma Designs Tango PCIe controller
  PCI: rockchip: Use normal register bank for config accessors
  dt-bindings: PCI: Add documentation for MediaTek PCIe
  PCI: Remove __pci_dev_reset() and pci_dev_reset()
  PCI: Split ->reset_notify() method into ->reset_prepare() and ->reset_done()
  PCI: xilinx: Make of_device_ids const
  PCI: xilinx-nwl: Modify IRQ chip for legacy interrupts
  PCI: vmd: Move SRCU cleanup after bus, child device removal
  PCI: vmd: Correct comment: VMD domains start at 0x10000, not 0x1000
  PCI: versatile: Add local struct device pointers
  PCI: tegra: Do not allocate MSI target memory
  PCI: tegra: Support MSI 64-bit addressing
  PCI: rockchip: Use local struct device pointer consistently
  PCI: rockchip: Check for clk_prepare_enable() errors during resume
  MAINTAINERS: Remove Wenrui Li as Rockchip PCIe driver maintainer
  PCI: rockchip: Configure RC's MPS setting
  PCI: rockchip: Reconfigure configuration space header type
  PCI: rockchip: Split out rockchip_pcie_cfg_configuration_accesses()
  PCI: rockchip: Move configuration accesses into rockchip_pcie_cfg_atu()
  ...
2017-07-08 15:51:57 -07:00
Daniel Lezcano c80081b920 genirq: Allow to pass the IRQF_TIMER flag with percpu irq request
The irq timings infrastructure tracks when interrupts occur in order to
statistically predict te next interrupt event.

There is no point to track timer interrupts and try to predict them because
the next expiration time is already known. This can be avoided via the
IRQF_TIMER flag which is passed by timer drivers in request_irq(). It marks
the interrupt as timer based which alloes to ignore these interrupts in the
timings code.

Per CPU interrupts which are requested via request_percpu_+irq() have no
flag argument, so marking per cpu timer interrupts is not possible and they
get tracked pointlessly.

Add __request_percpu_irq() as a variant of request_percpu_irq() with a
flags argument and make request_percpu_irq() an inline wrapper passing
flags = 0.

The flag parameter is restricted to IRQF_TIMER as all other IRQF_ flags
make no sense for per cpu interrupts.

The next step is to convert all existing users of request_percpu_irq() and
then remove the wrapper and the underscores.

[ tglx: Massaged changelog ]

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: peterz@infradead.org
Cc: nicolas.pitre@linaro.org
Cc: vincent.guittot@linaro.org
Cc: rafael@kernel.org
Link: http://lkml.kernel.org/r/1499344144-3964-1-git-send-email-daniel.lezcano@linaro.org
2017-07-06 23:16:22 +02:00
Daniel Lezcano e1c9214955 genirq/timings: Add infrastructure for estimating the next interrupt arrival time
An interrupt behaves with a burst of activity with periodic interval of time
followed by one or two peaks of longer interval.

As the time intervals are periodic, statistically speaking they follow a normal
distribution and each interrupts can be tracked individually.

Add a mechanism to compute the statistics on all interrupts, except the
timers which are deterministic from a prediction point of view, as their
expiry time is known.

The goal is to extract the periodicity for each interrupt, with the last
timestamp and sum them, so the next event can be predicted to a certain
extent.

Taking the earliest prediction gives the expected wakeup on the system
(assuming a timer won't expire before).

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: "Rafael J . Wysocki" <rafael@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Link: http://lkml.kernel.org/r/1498227072-5980-2-git-send-email-daniel.lezcano@linaro.org
2017-06-24 11:44:39 +02:00
Daniel Lezcano b2d3d61adb genirq/timings: Add infrastructure to track the interrupt timings
The interrupt framework gives a lot of information about each interrupt. It
does not keep track of when those interrupts occur though, which is a
prerequisite for estimating the next interrupt arrival for power management
purposes.

Add a mechanism to record the timestamp for each interrupt occurrences in a
per-CPU circular buffer to help with the prediction of the next occurrence
using a statistical model.

Each CPU can store up to IRQ_TIMINGS_SIZE events <irq, timestamp>, the
current value of IRQ_TIMINGS_SIZE is 32.

Each event is encoded into a single u64, where the high 48 bits are used
for the timestamp and the low 16 bits are for the irq number.

A static key is introduced so when the irq prediction is switched off at
runtime, the overhead is near to zero.

It results in most of the code in internals.h for inline reasons and a very
few in the new file timings.c. The latter will contain more in the next patch
which will provide the statistical model for the next event prediction.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: "Rafael J . Wysocki" <rafael@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Link: http://lkml.kernel.org/r/1498227072-5980-1-git-send-email-daniel.lezcano@linaro.org
2017-06-24 11:44:11 +02:00
Michael Hernandez 6f9a22bc57 PCI/MSI: Ignore affinity if pre/post vector count is more than min_vecs
min_vecs is the minimum amount of vectors needed to operate in MSI-X mode
which may just include the vectors that don't need affinity.

Disabling affinity settings causes the qla2xxx driver scsi_add_host() to fail
when blk_mq is enabled as the blk_mq_pci_map_queues() expects affinity masks
on each vector.

Fixes: dfef358bd1 ("PCI/MSI: Don't apply affinity if there aren't enough vectors left")
Signed-off-by: Michael Hernandez <michael.hernandez@cavium.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org	# v4.10+
2017-05-22 15:06:05 -05:00
Christoph Hellwig 25ce4be724 genirq: Return the IRQ name from free_irq()
This allows callers to get back at them instead of having to store it in
another variable.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-18 13:40:00 -05:00