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2018-01-16hrtimer: Make hrtimer_force_reprogramm() unconditionally availableAnna-Maria Gleixner1-32/+28
hrtimer_force_reprogram() needs to be available unconditionally for softirq based hrtimers. Move the function and all required struct members out of the CONFIG_HIGH_RES_TIMERS #ifdef. There is no functional change because hrtimer_force_reprogram() is only invoked when hrtimer_cpu_base.hres_active is true and CONFIG_HIGH_RES_TIMERS=y. Making it unconditional increases the text size for the CONFIG_HIGH_RES_TIMERS=n case slightly, but avoids replication of that code for the upcoming softirq based hrtimers support. Most of the code gets eliminated in the CONFIG_HIGH_RES_TIMERS=n case by the compiler. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@chromium.org Link: http://lkml.kernel.org/r/20171221104205.7269-19-anna-maria@linutronix.de [ Made it build on !CONFIG_HIGH_RES_TIMERS ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16hrtimer: Make hrtimer_reprogramm() unconditionalAnna-Maria Gleixner2-70/+65
hrtimer_reprogram() needs to be available unconditionally for softirq based hrtimers. Move the function and all required struct members out of the CONFIG_HIGH_RES_TIMERS #ifdef. There is no functional change because hrtimer_reprogram() is only invoked when hrtimer_cpu_base.hres_active is true. Making it unconditional increases the text size for the CONFIG_HIGH_RES_TIMERS=n case, but avoids replication of that code for the upcoming softirq based hrtimers support. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@chromium.org Link: http://lkml.kernel.org/r/20171221104205.7269-18-anna-maria@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16hrtimer: Make hrtimer_cpu_base.next_timer handling unconditionalAnna-Maria Gleixner2-12/+4
hrtimer_cpu_base.next_timer stores the pointer to the next expiring timer in a CPU base. This pointer cannot be dereferenced and is solely used to check whether a hrtimer which is removed is the hrtimer which is the first to expire in the CPU base. If this is the case, then the timer hardware needs to be reprogrammed to avoid an extra interrupt for nothing. Again, this is conditional functionality, but there is no compelling reason to make this conditional. As a preparation, hrtimer_cpu_base.next_timer needs to be available unconditonally. Aside of that the upcoming support for softirq based hrtimers requires access to this pointer unconditionally as well, so our motivation is not entirely simplicity based. Make the update of hrtimer_cpu_base.next_timer unconditional and remove the #ifdef cruft. The impact on CONFIG_HIGH_RES_TIMERS=n && CONFIG_NOHZ=n is marginal as it's just a store on an already dirtied cacheline. No functional change. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@chromium.org Link: http://lkml.kernel.org/r/20171221104205.7269-17-anna-maria@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16hrtimer: Make the remote enqueue check unconditionalAnna-Maria Gleixner2-23/+9
hrtimer_cpu_base.expires_next is used to cache the next event armed in the timer hardware. The value is used to check whether an hrtimer can be enqueued remotely. If the new hrtimer is expiring before expires_next, then remote enqueue is not possible as the remote hrtimer hardware cannot be accessed for reprogramming to an earlier expiry time. The remote enqueue check is currently conditional on CONFIG_HIGH_RES_TIMERS=y and hrtimer_cpu_base.hres_active. There is no compelling reason to make this conditional. Move hrtimer_cpu_base.expires_next out of the CONFIG_HIGH_RES_TIMERS=y guarded area and remove the conditionals in hrtimer_check_target(). The check is currently a NOOP for the CONFIG_HIGH_RES_TIMERS=n and the !hrtimer_cpu_base.hres_active case because in these cases nothing updates hrtimer_cpu_base.expires_next yet. This will be changed with later patches which further reduce the #ifdef zoo in this code. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@chromium.org Link: http://lkml.kernel.org/r/20171221104205.7269-16-anna-maria@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16hrtimer: Use accesor functions instead of direct accessAnna-Maria Gleixner1-2/+2
__hrtimer_hres_active() is now available unconditionally, so replace open coded direct accesses to hrtimer_cpu_base.hres_active. No functional change. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@chromium.org Link: http://lkml.kernel.org/r/20171221104205.7269-15-anna-maria@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16hrtimer: Make the hrtimer_cpu_base::hres_active field unconditional, to ↵Anna-Maria Gleixner2-28/+23
simplify the code The hrtimer_cpu_base::hres_active_member field depends on CONFIG_HIGH_RES_TIMERS=y currently, and all related functions to this member are conditional as well. To simplify the code make it unconditional and set it to zero during initialization. (This will also help with the upcoming softirq based hrtimers code.) The conditional code sections can be avoided by adding IS_ENABLED(HIGHRES) conditionals into common functions, which ensures dead code elimination. There is no functional change. Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: keescook@chromium.org Link: http://lkml.kernel.org/r/20171221104205.7269-14-anna-maria@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16hrtimer: Make room in 'struct hrtimer_cpu_base'Anna-Maria Gleixner1-2/+2
The upcoming softirq based hrtimers support requires an additional field in the hrtimer_cpu_base struct, which would grow the struct size beyond a cache line. The hrtimer_cpu_base::nr_retries and ::nr_hangs members are solely used for diagnostic output and have no requirement to be 'unsigned int'. Make them 'unsigned short' to create room for the new struct member. No functional change. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@chromium.org Link: http://lkml.kernel.org/r/20171221104205.7269-13-anna-maria@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16hrtimer: Store running timer in hrtimer_clock_baseAnna-Maria Gleixner2-26/+22
The pointer to the currently running timer is stored in hrtimer_cpu_base before the base lock is dropped and the callback is invoked. This results in two levels of indirections and the upcoming support for softirq based hrtimer requires splitting the "running" storage into soft and hard IRQ context expiry. Storing both in the cpu base would require conditionals in all code paths accessing that information. It's possible to have a per clock base sequence count and running pointer without changing the semantics of the related mechanisms because the timer base pointer cannot be changed while a timer is running the callback. Unfortunately this makes cpu_clock base larger than 32 bytes on 32-bit kernels. Instead of having huge gaps due to alignment, remove the alignment and let the compiler pack CPU base for 32-bit kernels. The resulting cache access patterns are fortunately not really different from the current behaviour. On 64-bit kernels the 64-byte alignment stays and the behaviour is unchanged. This was determined by analyzing the resulting layout and looking at the number of cache lines involved for the frequently used clocks. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@chromium.org Link: http://lkml.kernel.org/r/20171221104205.7269-12-anna-maria@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16hrtimer: Switch 'for' loop to _ffs() evaluationAnna-Maria Gleixner1-10/+21
Looping over all clock bases to find active bits is suboptimal if not all bases are active. Avoid this by converting it to a __ffs() evaluation. The functionallity is outsourced into its own function and is called via a macro as suggested by Peter Zijlstra. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@chromium.org Link: http://lkml.kernel.org/r/20171221104205.7269-11-anna-maria@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16tracing/hrtimer: Print the hrtimer mode in the 'hrtimer_start' tracepointAnna-Maria Gleixner2-12/+17
The 'hrtimer_start' tracepoint lacks the mode information. The mode is important because consecutive starts can switch from ABS to REL or from PINNED to non PINNED. Append the mode field. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@chromium.org Link: http://lkml.kernel.org/r/20171221104205.7269-10-anna-maria@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16tracing/hrtimer: Fix tracing bugs by taking all clock bases and modes into ↵Anna-Maria Gleixner1-4/+16
account So far only CLOCK_MONOTONIC and CLOCK_REALTIME were taken into account as well as HRTIMER_MODE_ABS/REL in the hrtimer_init tracepoint. The query for detecting the ABS or REL timer modes is not valid anymore, it got broken by the introduction of HRTIMER_MODE_PINNED. HRTIMER_MODE_PINNED is not evaluated in the hrtimer_init() call, but for the sake of completeness print all given modes. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@chromium.org Link: http://lkml.kernel.org/r/20171221104205.7269-9-anna-maria@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16hrtimer: Clean up 'enum hrtimer_mode'Anna-Maria Gleixner1-5/+11
It's not obvious that the HRTIMER_MODE variants are bit combinations, because all modes are hard coded constants currently. Change it so the bit meanings are clear; and use the symbols for creating modes which combine bits. While at it get rid of the ugly tail comments as well. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@chromium.org Link: http://lkml.kernel.org/r/20171221104205.7269-8-anna-maria@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16hrtimer: Ensure POSIX compliance (relative CLOCK_REALTIME hrtimers)Anna-Maria Gleixner1-1/+6
The POSIX specification defines that relative CLOCK_REALTIME timers are not affected by clock modifications. Those timers have to use CLOCK_MONOTONIC to ensure POSIX compliance. The introduction of the additional HRTIMER_MODE_PINNED mode broke this requirement for pinned timers. There is no user space visible impact because user space timers are not using pinned mode, but for consistency reasons this needs to be fixed. Check whether the mode has the HRTIMER_MODE_REL bit set instead of comparing with HRTIMER_MODE_ABS. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@chromium.org Fixes: 597d0275736d ("timers: Framework for identifying pinned timers") Link: http://lkml.kernel.org/r/20171221104205.7269-7-anna-maria@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16hrtimer: Fix hrtimer_start[_range_ns]() function descriptionsAnna-Maria Gleixner2-7/+8
The hrtimer_start[_range_ns]() functions start a timer reliably on this CPU only when HRTIMER_MODE_PINNED is set. Furthermore the HRTIMER_MODE_PINNED mode is not considered when a hrtimer is initialized. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@chromium.org Link: http://lkml.kernel.org/r/20171221104205.7269-6-anna-maria@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16hrtimer: Clean up the 'int clock' parameter of schedule_hrtimeout_range_clock()Anna-Maria Gleixner2-7/+7
schedule_hrtimeout_range_clock() uses an 'int clock' parameter for the clock ID, instead of the customary predefined "clockid_t" type. In hrtimer coding style the canonical variable name for the clock ID is 'clock_id', therefore change the name of the parameter here as well to make it all consistent. While at it, clean up the description for the 'clock_id' and 'mode' function parameters. The clock modes and the clock IDs are not restricted as the comment suggests. Fix the mode description as well for the callers of schedule_hrtimeout_range_clock(). No functional changes intended. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@chromium.org Link: http://lkml.kernel.org/r/20171221104205.7269-5-anna-maria@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16hrtimer: Fix kerneldoc syntax for 'struct hrtimer_cpu_base'Anna-Maria Gleixner1-4/+4
The '/**' sequence marks the start of a structure description. Add the missing second asterisk. While at it adapt the ordering of the struct members to the struct definition and document the purpose of expires_next more precisely. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: keescook@chromium.org Link: http://lkml.kernel.org/r/20171221104205.7269-4-anna-maria@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16hrtimer: Correct blatantly incorrect commentThomas Gleixner1-3/+3
The protection of a hrtimer which runs its callback against migration to a different CPU has nothing to do with hard interrupt context. The protection against migration of a hrtimer running the expiry callback is the pointer in the cpu_base which holds a pointer to the currently running timer. This pointer is evaluated in the code which potentially switches the timer base and makes sure it's kept on the CPU on which the callback is running. Reported-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: keescook@chromium.org Link: http://lkml.kernel.org/r/20171221104205.7269-3-anna-maria@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16hrtimer: Optimize the hrtimer code by using static keys for ↵Thomas Gleixner5-65/+60
migration_enable/nohz_active The hrtimer_cpu_base::migration_enable and ::nohz_active fields were originally introduced to avoid accessing global variables for these decisions. Still that results in a (cache hot) load and conditional branch, which can be avoided by using static keys. Implement it with static keys and optimize for the most critical case of high performance networking which tends to disable the timer migration functionality. No change in functionality. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: keescook@chromium.org Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1801142327490.2371@nanos Link: https://lkml.kernel.org/r/20171221104205.7269-2-anna-maria@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-16Merge branch 'timers/urgent' into timers/core, to pick up dependent fixIngo Molnar95-341/+616
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-15timers: Unconditionally check deferrable baseThomas Gleixner1-1/+1
When the timer base is checked for expired timers then the deferrable base must be checked as well. This was missed when making the deferrable base independent of base::nohz_active. Fixes: ced6d5c11d3e ("timers: Use deferrable base independent of base::nohz_active") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: stable@vger.kernel.org Cc: rt@linutronix.de
2018-01-14posix-cpu-timers: Make set_process_cpu_timer() more robustMax R. P. Grossmann1-2/+1
Because the return value of cpu_timer_sample_group() is not checked, compilers and static checkers can legitimately warn about a potential use of the uninitialized variable 'now'. This is not a runtime issue as all call sites hand in valid clock ids. Also cpu_timer_sample_group() is invoked unconditionally even when the result is not used because *oldval is NULL. Make the invocation conditional and check the return value. [ tglx: Massage changelog ] Signed-off-by: Max R. P. Grossmann <m@max.pm> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: john.stultz@linaro.org Link: https://lkml.kernel.org/r/20180108190157.10048-1-m@max.pm
2018-01-08clocksource/drivers/stm32: Start the timer's counter soonerDaniel Lezcano1-3/+18
As we have a lot of timers on this platform, we can have potentially all the timers enabled in the DT, so we don't want to start the timer for every probe otherwise they will be running for nothing as only one will be used. Start the timer only when setting the mode or when the clocksource is enabled. Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1515418139-23276-20-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08clocksource/drivers/stm32: Add the timer delay callbackDaniel Lezcano1-0/+13
Add the timer delay callback, that saves us ~90ms of boot time. Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1515418139-23276-19-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08clocksource/drivers/stm32: Add clocksource functionalityBenjamin Gaignard1-0/+37
The scene is set for the clocksource functionality, let's add it for this driver. Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1515418139-23276-18-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08clocksource/drivers/stm32: Factor out more of the clockevent codeDaniel Lezcano1-25/+82
In order to prepare the clocksource code, let's factor out the clockevent code, split the prescaler and timer width code into separate functions. Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1515418139-23276-17-git-send-email-daniel.lezcano@linaro.org [ Small edits. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08clocksource/drivers/stm32: Add oneshot modeBenjamin Gaignard1-12/+44
The stm32 timer block is able to have a counter and a comparator. Instead of using the auto-reload register for periodic events, we switch to oneshot mode by using the comparator register. The timer is able to generate an interrupt when the counter overflows but we don't want that as this counter will be use as a clocksource in the next patches. So it is disabled by the UDIS bit of the control register. Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1515418139-23276-16-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08clocksource/drivers/stm32: Compute a prescaler value with a targeted rateBenjamin Gaignard1-1/+11
The prescaler value is arbitrarily set to 1024 without any regard to the timer frequency. For 32-bit timers, there is no need to set a prescaler value as they wrap in an acceptable interval and give the opportunity to have precise timers on this platform. However, for 16-bit timers a prescaler value is needed if we don't want to wrap too often per second which is inefficient and adds more and more error margin. With a targeted clock of 10MHz, the 16 bits are precise enough whatever the timer frequency is as we will compute the prescaler. Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1515418139-23276-15-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08clocksource/drivers/stm32: Factor out the timer width sorting codeDaniel Lezcano1-7/+23
In order to clarify and encapsulate the code for upcoming changes, move the timer width check into a function and add some documentation. Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1515418139-23276-14-git-send-email-daniel.lezcano@linaro.org [ Spelling fixes. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08clocksource/drivers/stm32: Use the node name as timer nameDaniel Lezcano1-1/+1
As there are different timers on the stm32, use the node name for the timer name in order to give the indication of which timer the kernel is using. /proc/timer_list gives all the information with the right name, otherwise we end up digging in the kernel log and /proc/interrupt to do the connection between the used timer. Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1515418139-23276-13-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08clocksource/drivers/stm32: Convert the driver to timer_of primitivesBenjamin Gaignard2-114/+74
Convert the driver to use the timer_of() helpers. This allows the removal of a custom private structure, factors out and simplifies the code. [Daniel Lezcano]: Respin against the critical fix patch and massaged the changelog. Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1515418139-23276-12-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08clocksource/drivers/stm32: Fix kernel panic with multiple timersDaniel Lezcano1-1/+6
The current code hides a couple of bugs: - The global variable 'clock_event_ddata' is overwritten each time the init function is invoked. This is fixed with a kmemdup() instead of assigning the global variable. That prevents a memory corruption when several timers are defined in the DT. - The clockevent's event_handler is NULL if the time framework does not select the clockevent when registering it, this is fine but the init code generates in any case an interrupt leading to dereference this NULL pointer. The stm32 timer works with shadow registers, a mechanism to cache the registers. When a change is done in one buffered register, we need to artificially generate an event to force the timer to copy the content of the register to the shadowed register. The auto-reload register (ARR) is one of the shadowed register as well as the prescaler register (PSC), so in order to force the copy, we issue an event which in turn leads to an interrupt and the NULL dereference. This is fixed by inverting two lines where we clear the status register before enabling the update event interrupt. As this kernel crash is resulting from the combination of these two bugs, the fixes are grouped into a single patch. Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1515418139-23276-11-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08clocksource/drivers/timer-of: Don't request the resource by nameDaniel Lezcano1-4/+4
When the driver does not specify a name for the resource, don't use of_io_request_and_map() but of_iomap(). That prevents resource name allocation conflicts on some platforms which have the same name as the node. Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com> 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/1515418139-23276-10-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08clocksource/drivers/timer-of: Store the device node pointer in 'struct timer_of'Daniel Lezcano2-0/+4
Under certain circumstances, some specific operations must be done with the device node pointer, which forces the timer code to propagate the pointer to the functions which need it. In order to consolidate the function signatures in the different drivers by using the timer-of structure, let's store it in the timer-of structure as a handy pointer when it is needed. Tested-by: Benjamin Gaignard <benjamin.gaignard@st.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Benjamin Gaignard <benjamin.gaignard@st.com> 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/1515418139-23276-9-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08clocksource/drivers/spreadtrum: Add timer driver for the Spreadtrum SC9860 ↵Baolin Wang3-0/+167
platform The Spreadtrum SC9860 platform will use the architected timers as local clock events, but we also need a broadcast timer device to wake up the CPUs when the CPUs are in sleep mode. The Spreadtrum timer can support 32-bit or 64-bit counters, as well as supporting period mode or one-shot mode. Signed-off-by: Baolin Wang <baolin.wang@spreadtrum.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Philippe Ombredanne <pombredanne@nexb.com> 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/1515418139-23276-8-git-send-email-daniel.lezcano@linaro.org [ Minor readability edits. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08dt-bindings/clocksource: Add Spreadtrum SC9860 timer documentationBaolin Wang1-0/+20
This patch adds documentation of device tree bindings for the timers found on the Spreadtrum SC9860 platform. Signed-off-by: Baolin Wang <baolin.wang@spreadtrum.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Rob Herring <robh@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: devicetree@vger.kernel.org Link: http://lkml.kernel.org/r/1515418139-23276-7-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08clocksource/drivers/timer-of: Add kernel documentationDaniel Lezcano1-0/+37
The current code has no comments, neither any function descriptions. Fix this by adding function descriptions in kernel doc format. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.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/1515418139-23276-6-git-send-email-daniel.lezcano@linaro.org [ Spelling and style fixes. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08clocksource/drivers/timer-of: Fix function namesDaniel Lezcano1-18/+18
All the functions are not prefixed with 'timer_of_', fix the naming in order to have the code consistent. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.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/1515418139-23276-5-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08clocksource/drivers/tcb_clksrc: Fix clock speed messageRomain Izard1-1/+1
The clock speed displayed at boot in an information message was 500 kHz too high compared to its real value. As the value is not used anywhere, there is no functional impact. Fix the rounding formula to display the correct value. Signed-off-by: Romain Izard <romain.izard.pro@gmail.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> 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/1515418139-23276-4-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08clocksource/drivers/owl: Add the S700 timerAndreas Färber1-0/+1
Actions S700 has two 2Hz timers like S500, and four TIMx timers like S900. Signed-off-by: Andreas Färber <afaerber@suse.de> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.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/1515418139-23276-3-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08clocksource/drivers/owl: Adopt TIMER_OF_DECLARE()Andreas Färber1-2/+2
The following commit: 1727339590fd ("clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLARE") deprecated CLOCKSOURCE_OF_DECLARE(), so adopt the new TIMER_OF_DECLARE() macro instead. Reported-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Andreas Färber <afaerber@suse.de> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.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/1515418139-23276-2-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-08dt-bindings/clocksource: Add Actions Semi S700 timerAndreas Färber1-0/+1
Define a compatible string for the Actions Semi S700 SoC timer. Signed-off-by: Andreas Färber <afaerber@suse.de> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Rob Herring <robh@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: devicetree@vger.kernel.org Link: http://lkml.kernel.org/r/1515418139-23276-1-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-06Merge tag 'for-4.15-rc7-tag' of ↵Linus Torvalds2-12/+34
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "We have two more fixes for 4.15, both aimed for stable. The leak fix is obvious, the second patch fixes a bug revealed by the refcount API, when it behaves differently than previous atomic_t and reports refs going from 0 to 1 in one case" * tag 'for-4.15-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: fix refcount_t usage when deleting btrfs_delayed_nodes btrfs: Fix flush bio leak
2018-01-05Merge tag 'xfs-4.15-fixes-10' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds3-19/+33
Pull XFS fixes from Darrick Wong: "I have just a few fixes for bugs and resource cleanup problems this week: - Fix resource cleanup of failed quota initialization - Fix integer overflow problems wrt s_maxbytes" * tag 'xfs-4.15-fixes-10' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: xfs: fix s_maxbytes overflow problems xfs: quota: check result of register_shrinker() xfs: quota: fix missed destroy of qi_tree_lock
2018-01-05Merge tag 'mfd-fixes-4.15-1' of ↵Linus Torvalds1-0/+3
git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd Pull MFD fix from Lee Jones: "Late bugfix to plug a leak in rtsx_pcr" * tag 'mfd-fixes-4.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd: mfd: rtsx: Release IRQ during shutdown
2018-01-05Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds10-43/+55
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull more x86 pti fixes from Thomas Gleixner: "Another small stash of fixes for fallout from the PTI work: - Fix the modules vs. KASAN breakage which was caused by making MODULES_END depend of the fixmap size. That was done when the cpu entry area moved into the fixmap, but now that we have a separate map space for that this is causing more issues than it solves. - Use the proper cache flush methods for the debugstore buffers as they are mapped/unmapped during runtime and not statically mapped at boot time like the rest of the cpu entry area. - Make the map layout of the cpu_entry_area consistent for 4 and 5 level paging and fix the KASLR vaddr_end wreckage. - Use PER_CPU_EXPORT for per cpu variable and while at it unbreak nvidia gfx drivers by dropping the GPL export. The subject line of the commit tells it the other way around, but I noticed that too late. - Fix the ASM alternative macros so they can be used in the middle of an inline asm block. - Rename the BUG_CPU_INSECURE flag to BUG_CPU_MELTDOWN so the attack vector is properly identified. The Spectre mitigations will come with their own bug bits later" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/pti: Rename BUG_CPU_INSECURE to BUG_CPU_MELTDOWN x86/alternatives: Add missing '\n' at end of ALTERNATIVE inline asm x86/tlb: Drop the _GPL from the cpu_tlbstate export x86/events/intel/ds: Use the proper cache flush method for mapping ds buffers x86/kaslr: Fix the vaddr_end mess x86/mm: Map cpu_entry_area at the same place on 4/5 level x86/mm: Set MODULES_END to 0xffffffffff000000
2018-01-05Merge branch 'efi-urgent-for-linus' of ↵Linus Torvalds5-17/+57
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull EFI updates from Thomas Gleixner: - A fix for a add_efi_memmap parameter regression which ensures that the parameter is parsed before it is used. - Reinstate the virtual capsule mapping as the cached copy turned out to break Quark and other things - Remove Matt Fleming as EFI co-maintainer. He stepped back a few days ago. Thanks Matt for all your great work! * 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: MAINTAINERS: Remove Matt Fleming as EFI co-maintainer efi/capsule-loader: Reinstate virtual capsule mapping x86/efi: Fix kernel param add_efi_memmap regression
2018-01-05Merge branch 'for-linus' of ↵Linus Torvalds5-3/+35
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 fixes from Martin Schwidefsky: "Four bug fixes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/dasd: fix wrongly assigned configuration data s390: fix preemption race in disable_sacf_uaccess s390/sclp: disable FORTIFY_SOURCE for early sclp code s390/pci: handle insufficient resources during dma tlb flush
2018-01-05Merge tag 'for-linus-4.15-rc7-tag' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fix from Juergen Gross: "One minor fix adjusting the kmalloc flags in the new pvcalls driver added in rc1" * tag 'for-linus-4.15-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen/pvcalls: use GFP_ATOMIC under spin lock
2018-01-05Merge branch 'linus' of ↵Linus Torvalds12-62/+173
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto fixes from Herbert Xu: "This fixes the following issues: - racy use of ctx->rcvused in af_alg - algif_aead crash in chacha20poly1305 - freeing bogus pointer in pcrypt - build error on MIPS in mpi - memory leak in inside-secure - memory overwrite in inside-secure - NULL pointer dereference in inside-secure - state corruption in inside-secure - build error without CRYPTO_GF128MUL in chelsio - use after free in n2" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: crypto: inside-secure - do not use areq->result for partial results crypto: inside-secure - fix request allocations in invalidation path crypto: inside-secure - free requests even if their handling failed crypto: inside-secure - per request invalidation lib/mpi: Fix umul_ppmm() for MIPS64r6 crypto: pcrypt - fix freeing pcrypt instances crypto: n2 - cure use after free crypto: af_alg - Fix race around ctx->rcvused by making it atomic_t crypto: chacha20poly1305 - validate the digest size crypto: chelsio - select CRYPTO_GF128MUL
2018-01-05Merge branch 'akpm' (patches from Andrew)Linus Torvalds12-23/+43
Merge misc fixes from Andrew Morton: "9 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: mailmap: update Mark Yao's email address userfaultfd: clear the vma->vm_userfaultfd_ctx if UFFD_EVENT_FORK fails mm/sparse.c: wrong allocation for mem_section mm/zsmalloc.c: include fs.h mm/debug.c: provide useful debugging information for VM_BUG kernel/exit.c: export abort() to modules mm/mprotect: add a cond_resched() inside change_pmd_range() kernel/acct.c: fix the acct->needcheck check in check_free_space() mm: check pfn_valid first in zero_resv_unavail