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2017-06-14clocksource/drivers/fttmr010: Implement delay timerLinus Walleij
This timer is often used on the ARM architecture, so as with so many siblings, we can implement delay timers, removing the need for the system to calibrate jiffys at boot, and potentially handling CPU frequency scaling on targets. We cannot just protect the Kconfig with a "depends on ARM" because it is already known that different architectures are using Faraday IP blocks, so it is better to make things open-ended and use Result on boot dmesg: Switching to timer-based delay loop, resolution 40n Calibrating delay loop (skipped), value calculated using timer frequency.. 50.00 BogoMIPS (lpj=250000) This is accurately the timer frequency, 250MHz on the APB bus. Cc: Andrew Jeffery <andrew@aj.id.au> Cc: Joel Stanley <joel@jms.id.au> Cc: Jonas Jensen <jonas.jensen@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Jonas Jensen <jonas.jensen@gmail.com> Tested-by: Andrew Jeffery <andrew@aj.id.au> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-06-14clocksource/drivers: Add timer-of common init routineDaniel Lezcano
The different drivers are all using the same pattern when initializing. 1. Get the base address 2. Get the irq number 3. Get the clock 4. Prepare and enable the clock 5. Get the rate 6. Request an interrupt Instead of repeating again and again these steps in all the drivers, let's provide a common init routine to give the opportunity to factor all of them out. We can expect a significant kernel size improvement when the common routine will be used in all the drivers. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-06-14clocksource/drivers/tcb_clksrc: Save timer context on suspend/resumeAlexandre Belloni
On sama5d2, power to the core may be cut while entering suspend mode. It is necessary to save and restore the TCB registers. Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-06-14clocksource/drivers/fttmr010: Optimize sched_clock()Linus Walleij
The sched_clock() call should be really fast so we want to avoid an extra if() clause on the read path if possible. Implement two sched_clock_read() functions, one if the timer counts up and one if it counts down. Incidentally this also mirrors how clocksource_mmio_init() works and make things simple and easy to understand. Suggested-by: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Andrew Jeffery <andrew@aj.id.au> Cc: Joel Stanley <joel@jms.id.au> Cc: Jonas Jensen <jonas.jensen@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-06-14clocksource/drivers: Add an alias macro CLOCKSOURCE_OF_DECLAREDaniel Lezcano
The macro CLOCKSOURCE_OF_DECLARE has been rename to TIMER_OF_DECLARE. In order to prevent conflicts for the next merge window, a temporary alias has been added which will be removed later. Cc: Arnd Bergman <arnd@arndb.de> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-06-14clocksource/drivers: Rename CLKSRC_ACPI to TIMER_ACPIDaniel Lezcano
The config option name is now renamed to 'TIMER_ACPI' for consistency with the CLOCKSOURCE_OF_DECLARE => TIMER_OF_DECLARE change. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2017-06-14clocksource/drivers: Rename CLKSRC_OF to TIMER_OFDaniel Lezcano
The config option name is now renamed to 'TIMER_OF' for consistency with the CLOCKSOURCE_OF_DECLARE => TIMER_OF_DECLARE change. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2017-06-14clocksource/drivers: Rename clksrc table to timerDaniel Lezcano
The table name is now renamed to 'timer' for consistency with the CLOCKSOURCE_OF_DECLARE => TIMER_OF_DECLARE change. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2017-06-14clocksource/drivers: Rename CLOCKSOURCE_ACPI_DECLARE to TIMER_ACPI_DECLAREDaniel Lezcano
The macro name is now renamed to 'TIMER_ACPI_DECLARE' for consistency with the CLOCKSOURCE_OF_DECLARE => TIMER_OF_DECLARE change. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2017-06-14clocksource/drivers: Rename clocksource_probe to timer_probeDaniel Lezcano
The function name is now renamed to 'timer_probe' for consistency with the CLOCKSOURCE_OF_DECLARE => TIMER_OF_DECLARE change. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Heiko Stuebner <heiko@sntech.de> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2017-06-14clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLAREDaniel Lezcano
The CLOCKSOURCE_OF_DECLARE macro is used widely for the timers to declare the clocksource at early stage. However, this macro is also used to initialize the clockevent if any, or the clockevent only. It was originally suggested to declare another macro to initialize a clockevent, so in order to separate the two entities even they belong to the same IP. This was not accepted because of the impact on the DT where splitting a clocksource/clockevent definition does not make sense as it is a Linux concept not a hardware description. On the other side, the clocksource has not interrupt declared while the clockevent has, so it is easy from the driver to know if the description is for a clockevent or a clocksource, IOW it could be implemented at the driver level. So instead of dealing with a named clocksource macro, let's use a more generic one: TIMER_OF_DECLARE. The patch has not functional changes. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Neil Armstrong <narmstrong@baylibre.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Matthias Brugger <matthias.bgg@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2017-06-12Revert "clockevents: Add a clkevt-of mechanism like clksrc-of"Daniel Lezcano
After discussing it, this feature is dropped as it is not considered adequate: https://patchwork.kernel.org/patch/9639317/ There is no user of this macro yet, so there is no impact on the drivers. This reverts commit 376bc27150f180d9f5eddec6a14117780177589d. Cc: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-06-12clocksource/drivers/fttmr010: Fix aspeed-2500 initializationDaniel Lezcano
The recent changes made the fttmr010 to be more generic and support different timers with a very few differences like moxart or aspeed. The aspeed timer uses a countdown and there is a test against the aspeed2400 compatible string to set a flag. With the previous patch, we added the aspeed2500 compatible string but without taking care of setting the countdown flag. Fix this by specifiying a init function and pass the aspeed flag to a common init function. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Andrew Jeffery <andrew@aj.id.au> Reviewed-by: Andrew Jeffery <andrew@aj.id.au> Acked-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-06-12clocksource/drivers/fttmr010: Add AST2500 compatible stringDaniel Lezcano
Also clean up space-before-tab issues in the documentation. Signed-off-by: Andrew Jeffery <andrew@aj.id.au> Acked-by: Joel Stanley <joel@jms.id.au> Acked-by: Rob Herring <robh@kernel.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-06-12clocksource/drivers/fttmr010: Merge Moxa into FTTMR010Linus Walleij
This merges the Moxa Art timer driver into the Faraday FTTMR010 driver and replaces all Kconfig symbols to use the Faraday driver instead. We are now so similar that the drivers can be merged by just adding a few lines to the Faraday timer. Differences: - The Faraday driver explicitly sets the counter to count upwards for the clocksource, removing the need for the clocksource core to invert the value. - The Faraday driver also handles sched_clock() On the Aspeed, the counter can only count downwards, so support the timers in downward-counting mode as well, and flag the Aspeed to use this mode. This mode was tested on the Gemini so I have high hopes that it'll work fine on the Aspeed as well. After this we have one driver for all three SoCs and a generic Faraday FTTMR010 timer driver, which is nice. Cc: Joel Stanley <joel@jms.id.au> Cc: Jonas Jensen <jonas.jensen@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Joel Stanley <joel@jms.id.au> Tested-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-06-12clocksource/drivers/fttmr010: Switch to use TIMER2 srcLinus Walleij
This switches the clocksource to TIMER2 like the Moxart driver does. Mainly to make it more similar to the Moxart/Aspeed driver but also because it seems more neat to use the timers in order: use timer 1, then timer 2. Cc: Joel Stanley <joel@jms.id.au> Tested-by: Jonas Jensen <jonas.jensen@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-06-12clocksource/drivers/fttmr010: Switch to use bitopsLinus Walleij
This switches the drivers to use the bitops BIT() macro to define bits. Cc: Joel Stanley <joel@jms.id.au> Tested-by: Jonas Jensen <jonas.jensen@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-06-12clocksource/drivers/fttmr010: Use state containerLinus Walleij
This converts the Faraday FTTMR010 to use the state container design pattern. Take some care to handle the state container and free:ing of resources as has been done in the Moxa driver. Cc: Joel Stanley <joel@jms.id.au> Tested-by: Jonas Jensen <jonas.jensen@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-06-12clocksource/drivers/fttmr010: Drop Gemini specificsLinus Walleij
The Gemini now has a proper clock driver and a proper PCLK assigned in its device tree. Drop the Gemini-specific hacks to look up the system speed and rely on the clock framework like everyone else. Cc: Joel Stanley <joel@jms.id.au> Tested-by: Jonas Jensen <jonas.jensen@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-06-12clocksource/drivers/fttmr010: Merge FTTMR010 DT bindingsLinus Walleij
This merges the Moxa and FTTMR010 device tree bindings into the Faraday binding document to avoid confusion. The FTTMR010 is the IP block used by these SoCs, in vanilla or modified variant. The Aspeed variant is modified such that it is no longer fully register-compatible with FTTMR010 so for this reason it is not listed with two compatible strings, instead just one. Cc: Joel Stanley <joel@jms.id.au> Tested-by: Jonas Jensen <jonas.jensen@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Rob Herring <robh@kernel.org> Acked-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-06-12clocksource/drivers/fttmr010: Fix the clock handlingLinus Walleij
We need to also prepare and enable the clock we are using to get the right reference count and avoid it being shut off. Tested-by: Jonas Jensen <jonas.jensen@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-06-12arm: aspeed: Add clock-names property to timer nodeAndrew Jeffery
The merging of a number of clocksource drivers into fttmr010 means we require clock-names to be specified in the Aspeed timer node, else the clocksource fails to probe and boot hangs. Signed-off-by: Andrew Jeffery <andrew@aj.id.au> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-06-04alarmtimer: Switch over to generic set/get/rearm routineThomas Gleixner
All required callbacks are in place. Switch the alarm timer based posix interval timer callbacks to the common implementation and remove the incorrect private implementation. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.825471962@linutronix.de
2017-06-04alarmtimer: Implement arm callbackThomas Gleixner
Preparatory change to utilize the common posix timer mechanisms. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.747567162@linutronix.de
2017-06-04alarmtimer: Implement try_to_cancel callbackThomas Gleixner
Preparatory change to utilize the common posix timer mechanisms. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.670026824@linutronix.de
2017-06-04alarmtimer: Implement remaining callbackThomas Gleixner
Preparatory change to utilize the common posix timer mechanisms. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.592676753@linutronix.de
2017-06-04alarmtimer: Implement forward callbackThomas Gleixner
Preparatory change to utilize the common posix timer mechanisms. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.513694229@linutronix.de
2017-06-04alarmtimer: Implement timer_rearm() callbackThomas Gleixner
Preparatory change to utilize the common posix timer mechanisms. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.434598989@linutronix.de
2017-06-04posix-timers: Make use of cancel/arm callbacksThomas Gleixner
Replace the hrtimer calls by calls to the new try_to_cancel()/arm() kclock callbacks and move the hrtimer specific implementation into the corresponding callback functions. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.355396667@linutronix.de
2017-06-04posix-timers: Add cancel/arm callbacksThomas Gleixner
Add timer_try_to_cancel() and timer_arm() callbacks to kclock which allow to make common_timer_set() usable by both hrtimer and alarmtimer based clocks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.278022962@linutronix.de
2017-06-04posix-timers: Zero settings value in common codeThomas Gleixner
Zero out the settings struct in the common code so the callbacks do not have to do it themself. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.200870713@linutronix.de
2017-06-04posix-timers: Make use of forward/remaining callbacksThomas Gleixner
Replace the hrtimer calls by calls to the new forward/remaining kclock callbacks and move the hrtimer specific implementation into the corresponding callback functions. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.121437232@linutronix.de
2017-06-04posix-timers: Add forward/remaining callbacksThomas Gleixner
Add two callbacks to kclock which allow using common_)timer_get() for both hrtimer and alarm timer based clocks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211657.044915536@linutronix.de
2017-06-04posix-timers: Add active flag to k_itimerThomas Gleixner
Keep track of the activation state of posix timers. This is a preparatory change for making common_timer_get() usable by both hrtimer and alarm timer implementations. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.967783982@linutronix.de
2017-06-04posix-timers: Use timer_rearm() callback in posixtimer_rearm()Thomas Gleixner
Use the new timer_rearm() callback to replace the conditional hardcoded calls into the hrtimer and cpu timer code. This allows later to bring the same logic to alarmtimers. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.889661919@linutronix.de
2017-06-04posix-timers: Rename do_schedule_next_timerThomas Gleixner
That function is a misnomer. Rename it with a proper prefix to posixtimer_rearm(). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.811362578@linutronix.de
2017-06-04posix-timers: Add timer_rearm() callbackThomas Gleixner
Add a timer_rearm() callback which is used to make the rescheduling of posix interval timers independent of the underlying clock implementation. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.732632167@linutronix.de
2017-06-04posix-timers: Store k_clock pointer in k_itimerThomas Gleixner
Having the k_clock pointer in the k_itimer struct avoids the lookup in several code pathes and makes the next steps of unification of the hrtimer and alarmtimer based posix timers simpler. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.641222072@linutronix.de
2017-06-04posix-timers: Move interval out of the unionThomas Gleixner
Preparatory patch to unify the alarm timer and hrtimer based posix interval timer handling. The interval is used as a criteria for rearming decisions so moving it out of the clock specific data structures allows later unification. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.563922908@linutronix.de
2017-06-04posix-timers: Unify overrun/requeue_pending handlingThomas Gleixner
hrtimer based posix-timers and posix-cpu-timers handle the update of the rearming and overflow related status fields differently. Move that update to the common rearming code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.484936964@linutronix.de
2017-06-04posix-timers: Move posix-timer internals to coreThomas Gleixner
None of these declarations is required outside of kernel/time. Move them to an internal header. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Cc: Christoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/20170530211656.394803853@linutronix.de
2017-06-04posix-timers: Cleanup struct k_itimerThomas Gleixner
As a preparation for further changes, cleanup the formatting of the k_itimer structure and add kernel doc comments. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.316574129@linutronix.de
2017-06-04posix-timers: Avoid gazillions of forward declarationsThomas Gleixner
Move it below the actual implementations as there are new callbacks coming which would require even more forward declarations. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.238209952@linutronix.de
2017-06-04posix-clocks: Remove interval timer facility and mmap/fasync callbacksThomas Gleixner
The only user of this facility is ptp_clock, which does not implement any of those functions. Remove them to prevent accidental users. Especially the interval timer interfaces are now more or less impossible to implement because the necessary infrastructure has been confined to the core code. Aside of that it's really complex to make these callbacks implemented according to spec as the alarm timer implementation demonstrates. If at all then a nanosleep callback might be a reasonable extension. For now keep just what ptp_clock needs. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.145036286@linutronix.de
2017-06-04posix-timers: Remove unused export of posix_timer_event()Thomas Gleixner
Since the removal of the mmtimer driver the export is not longer needed. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211656.052744418@linutronix.de
2017-06-04alarmtimer: Remove pointless config conditionalThomas Gleixner
Having a IF_ENABLED(CONFIG_POSIX_TIMERS) inside of a #ifdef CONFIG_POSIX_TIMERS section is pointless. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20170530211655.975218056@linutronix.de
2017-06-04Merge branch 'timers/urgent' into WIP.timersThomas Gleixner
Pick up urgent fixes to avoid conflicts.
2017-06-04alarmtimer: Rate limit periodic intervalsThomas Gleixner
The alarmtimer code has another source of potentially rearming itself too fast. Interval timers with a very samll interval have a similar CPU hog effect as the previously fixed overflow issue. The reason is that alarmtimers do not implement the normal protection against this kind of problem which the other posix timer use: timer expires -> queue signal -> deliver signal -> rearm timer This scheme brings the rearming under scheduler control and prevents permanently firing timers which hog the CPU. Bringing this scheme to the alarm timer code is a major overhaul because it lacks all the necessary mechanisms completely. So for a quick fix limit the interval to one jiffie. This is not problematic in practice as alarmtimers are usually backed by an RTC for suspend which have 1 second resolution. It could be therefor argued that the resolution of this clock should be set to 1 second in general, but that's outside the scope of this fix. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Kostya Serebryany <kcc@google.com> Cc: syzkaller <syzkaller@googlegroups.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20170530211655.896767100@linutronix.de
2017-06-04alarmtimer: Prevent overflow of relative timersThomas Gleixner
Andrey reported a alartimer related RCU stall while fuzzing the kernel with syzkaller. The reason for this is an overflow in ktime_add() which brings the resulting time into negative space and causes immediate expiry of the timer. The following rearm with a small interval does not bring the timer back into positive space due to the same issue. This results in a permanent firing alarmtimer which hogs the CPU. Use ktime_add_safe() instead which detects the overflow and clamps the result to KTIME_SEC_MAX. Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Kostya Serebryany <kcc@google.com> Cc: syzkaller <syzkaller@googlegroups.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20170530211655.802921648@linutronix.de
2017-06-04signal: Remove non-uapi <asm/siginfo.h>Christoph Hellwig
By moving the kernel side __SI_* defintions right next to the userspace ones we can kill the non-uapi versions of <asm/siginfo.h> include include/asm-generic/siginfo.h and untangle the unholy mess of includes. [ tglx: Removed uapi/asm/siginfo.h from m32r, microblaze, mn10300 and score ] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: linux-ia64@vger.kernel.org Cc: Arnd Bergmann <arnd@arndb.de> Cc: sparclinux@vger.kernel.org Cc: "David S. Miller" <davem@davemloft.net> Link: http://lkml.kernel.org/r/20170603190102.28866-6-hch@lst.de