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2015-09-01Merge branch 'timers-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "Rather large, but nothing exiting: - new range check for settimeofday() to prevent that boot time becomes negative. - fix for file time rounding - a few simplifications of the hrtimer code - fix for the proc/timerlist code so the output of clock realtime timers is accurate - more y2038 work - tree wide conversion of clockevent drivers to the new callbacks" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (88 commits) hrtimer: Handle failure of tick_init_highres() gracefully hrtimer: Unconfuse switch_hrtimer_base() a bit hrtimer: Simplify get_target_base() by returning current base hrtimer: Drop return code of hrtimer_switch_to_hres() time: Introduce timespec64_to_jiffies()/jiffies_to_timespec64() time: Introduce current_kernel_time64() time: Introduce struct itimerspec64 time: Add the common weak version of update_persistent_clock() time: Always make sure wall_to_monotonic isn't positive time: Fix nanosecond file time rounding in timespec_trunc() timer_list: Add the base offset so remaining nsecs are accurate for non monotonic timers cris/time: Migrate to new 'set-state' interface kernel: broadcast-hrtimer: Migrate to new 'set-state' interface xtensa/time: Migrate to new 'set-state' interface unicore/time: Migrate to new 'set-state' interface um/time: Migrate to new 'set-state' interface sparc/time: Migrate to new 'set-state' interface sh/localtimer: Migrate to new 'set-state' interface score/time: Migrate to new 'set-state' interface s390/time: Migrate to new 'set-state' interface ...
2015-08-17time: Introduce timespec64_to_jiffies()/jiffies_to_timespec64()Baolin Wang
The conversion between struct timespec and jiffies is not year 2038 safe on 32bit systems. Introduce timespec64_to_jiffies() and jiffies_to_timespec64() functions which use struct timespec64 to make it ready for 2038 issue. Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-08-17time: Fix nanosecond file time rounding in timespec_trunc()Karsten Blees
timespec_trunc() avoids rounding if granularity <= nanoseconds-per-jiffie (or TICK_NSEC). This optimization assumes that: 1. current_kernel_time().tv_nsec is already rounded to TICK_NSEC (i.e. with HZ=1000 you'd get 1000000, 2000000, 3000000... but never 1000001). This is no longer true (probably since hrtimers introduced in 2.6.16). 2. TICK_NSEC is evenly divisible by all possible granularities. This may be true for HZ=100, 250, 1000, but obviously not for HZ=300 / TICK_NSEC=3333333 (introduced in 2.6.20). Thus, sub-second portions of in-core file times are not rounded to on-disk granularity. I.e. file times may change when the inode is re-read from disk or when the file system is remounted. This affects all file systems with file time granularities > 1 ns and < 1s, e.g. CEPH (1000 ns), UDF (1000 ns), CIFS (100 ns), NTFS (100 ns) and FUSE (configurable from user mode via struct fuse_init_out.time_gran). Steps to reproduce with e.g. UDF: $ dd if=/dev/zero of=udfdisk count=10000 && mkudffs udfdisk $ mkdir udf && mount udfdisk udf $ touch udf/test && stat -c %y udf/test 2015-06-09 10:22:56.130006767 +0200 $ umount udf && mount udfdisk udf $ stat -c %y udf/test 2015-06-09 10:22:56.130006000 +0200 Remounting truncates the mtime to 1 µs. Fix the rounding in timespec_trunc() and update the documentation. timespec_trunc() is exclusively used to calculate inode's [acm]time (mostly via current_fs_time()), and always with super_block.s_time_gran as second argument. So this can safely be changed without side effects. Note: This does _not_ fix the issue for FAT's 2 second mtime resolution, as super_block.s_time_gran isn't prepared to handle different ctime / mtime / atime resolutions nor resolutions > 1 second. Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Karsten Blees <blees@dcon.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-07-29jiffies: Remove HZ > USEC_PER_SEC special caseFrederic Weisbecker
HZ never goes much further 1000 and a bit. And if we ever reach one tick per microsecond, we might be having a problem. Lets stop maintaining this special case, just leave a paranoid check. Reviewed-by: Rik van Riel <riel@redhat.com> Cc: Christoph Lameter <cl@linux.com> Cc: Ingo Molnar <mingo@kernel.org> Cc; John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2015-06-10time: Refactor usecs_to_jiffiesNicholas Mc Guire
Refactor the usecs_to_jiffies conditional code part in time.c and jiffies.h putting it into conditional functions rather than #ifdefs to improve readability. This is analogous to the msecs_to_jiffies() cleanup in commit ca42aaf0c861 ("time: Refactor msecs_to_jiffies") Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Cc: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Joe Perches <joe@perches.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Andrew Hunter <ahh@google.com> Cc: Paul Turner <pjt@google.com> Cc: Michal Marek <mmarek@suse.cz> Link: http://lkml.kernel.org/r/1432832996-12129-1-git-send-email-hofrat@osadl.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-05-22time: Make sure tz_minuteswest is set to a valid value when setting timeSasha Levin
Invalid values may overflow later, leading to undefined behaviour when multiplied by 60 to get the amount of seconds. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-05-19time: Refactor msecs_to_jiffiesNicholas Mc Guire
Refactor the msecs_to_jiffies conditional code part in time.c and jiffies.h putting it into conditional functions rather than #ifdefs to improve readability. [ tglx: Verified that there is no binary code change ] Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Cc: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Joe Perches <joe@perches.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Andrew Hunter <ahh@google.com> Cc: Paul Turner <pjt@google.com> Cc: Michal Marek <mmarek@suse.cz> Link: http://lkml.kernel.org/r/1431951554-5563-2-git-send-email-hofrat@osadl.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-05-19time: Move timeconst.h into include/generatedNicholas Mc Guire
kernel/time/timeconst.h is moved to include/generated/ and generated by the top level Kbuild. This allows using timeconst.h in an earlier build stage. Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Cc: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Joe Perches <joe@perches.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Andrew Hunter <ahh@google.com> Cc: Paul Turner <pjt@google.com> Cc: Michal Marek <mmarek@suse.cz> Link: http://lkml.kernel.org/r/1431951554-5563-1-git-send-email-hofrat@osadl.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-01-25Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: "A set of small fixes: - regression fix for exynos_mct clocksource - trivial build fix for kona clocksource - functional one liner fix for the sh_tmu clocksource - two validation fixes to prevent (root only) data corruption in the kernel via settimeofday and adjtimex. Tagged for stable" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: time: adjtimex: Validate the ADJ_FREQUENCY values time: settimeofday: Validate the values of tv from user clocksource: sh_tmu: Set cpu_possible_mask to fix SMP broadcast clocksource: kona: fix __iomem annotation clocksource: exynos_mct: Fix bitmask regression for exynos4_mct_write
2015-01-22Merge branch 'fortglx/3.19-stable/time' of ↵Thomas Gleixner
https://git.linaro.org/people/john.stultz/linux into timers/urgent Pull urgent fixes from John Stultz: Two urgent fixes for user triggerable time related overflow issues
2015-01-07time: settimeofday: Validate the values of tv from userSasha Levin
An unvalidated user input is multiplied by a constant, which can result in an undefined behaviour for large values. While this is validated later, we should avoid triggering undefined behaviour. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> [jstultz: include trivial milisecond->microsecond correction noticed by Andy] Signed-off-by: John Stultz <john.stultz@linaro.org>
2014-12-15Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linuxLinus Torvalds
Pull drm updates from Dave Airlie: "Highlights: - AMD KFD driver merge This is the AMD HSA interface for exposing a lowlevel interface for GPGPU use. They have an open source userspace built on top of this interface, and the code looks as good as it was going to get out of tree. - Initial atomic modesetting work The need for an atomic modesetting interface to allow userspace to try and send a complete set of modesetting state to the driver has arisen, and been suffering from neglect this past year. No more, the start of the common code and changes for msm driver to use it are in this tree. Ongoing work to get the userspace ioctl finished and the code clean will probably wait until next kernel. - DisplayID 1.3 and tiled monitor exposed to userspace. Tiled monitor property is now exposed for userspace to make use of. - Rockchip drm driver merged. - imx gpu driver moved out of staging Other stuff: - core: panel - MIPI DSI + new panels. expose suggested x/y properties for virtual GPUs - i915: Initial Skylake (SKL) support gen3/4 reset work start of dri1/ums removal infoframe tracking fixes for lots of things. - nouveau: tegra k1 voltage support GM204 modesetting support GT21x memory reclocking work - radeon: CI dpm fixes GPUVM improvements Initial DPM fan control - rcar-du: HDMI support added removed some support for old boards slave encoder driver for Analog Devices adv7511 - exynos: Exynos4415 SoC support - msm: a4xx gpu support atomic helper conversion - tegra: iommu support universal plane support ganged-mode DSI support - sti: HDMI i2c improvements - vmwgfx: some late fixes. - qxl: use suggested x/y properties" * 'drm-next' of git://people.freedesktop.org/~airlied/linux: (969 commits) drm: sti: fix module compilation issue drm/i915: save/restore GMBUS freq across suspend/resume on gen4 drm: sti: correctly cleanup CRTC and planes drm: sti: add HQVDP plane drm: sti: add cursor plane drm: sti: enable auxiliary CRTC drm: sti: fix delay in VTG programming drm: sti: prepare sti_tvout to support auxiliary crtc drm: sti: use drm_crtc_vblank_{on/off} instead of drm_vblank_{on/off} drm: sti: fix hdmi avi infoframe drm: sti: remove event lock while disabling vblank drm: sti: simplify gdp code drm: sti: clear all mixer control drm: sti: remove gpio for HDMI hot plug detection drm: sti: allow to change hdmi ddc i2c adapter drm/doc: Document drm_add_modes_noedid() usage drm/i915: Remove '& 0xffff' from the mask given to WA_REG() drm/i915: Invert the mask and val arguments in wa_add() and WA_REG() drm: Zero out DRM object memory upon cleanup drm/i915/bdw: Fix the write setting up the WIZ hashing mode ...
2014-12-05drm/i915: compute wait_ioctl timeout correctlyDaniel Vetter
We've lost the +1 required for correct timeouts in commit 5ed0bdf21a85d78e04f89f15ccf227562177cbd9 Author: Thomas Gleixner <tglx@linutronix.de> Date: Wed Jul 16 21:05:06 2014 +0000 drm: i915: Use nsec based interfaces Use ktime_get_raw_ns() and get rid of the back and forth timespec conversions. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: John Stultz <john.stultz@linaro.org> So fix this up by reinstating our handrolled _timeout function. While at it bother with handling MAX_JIFFIES. v2: Convert to usecs (we don't care about the accuracy anyway) first to avoid overflow issues Dave Gordon spotted. v3: Drop the explicit MAX_JIFFY_OFFSET check, usecs_to_jiffies should take care of that already. It might be a bit too enthusiastic about it though. v4: Chris has a much nicer color, so use his implementation. This requires to export nsec_to_jiffies from time.c. Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Dave Gordon <david.s.gordon@intel.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=82749 Cc: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Acked-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2014-11-21time: Provide y2038 safe mktime() replacementpang.xunlei
As part of addressing "y2038 problem" for in-kernel uses, this patch adds safe mktime64() using time64_t. After this patch, mktime() is deprecated and all its call sites will be fixed using mktime64(), after that it can be removed. Signed-off-by: pang.xunlei <pang.xunlei@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org>
2014-09-12jiffies: Fix timeval conversion to jiffiesAndrew Hunter
timeval_to_jiffies tried to round a timeval up to an integral number of jiffies, but the logic for doing so was incorrect: intervals corresponding to exactly N jiffies would become N+1. This manifested itself particularly repeatedly stopping/starting an itimer: setitimer(ITIMER_PROF, &val, NULL); setitimer(ITIMER_PROF, NULL, &val); would add a full tick to val, _even if it was exactly representable in terms of jiffies_ (say, the result of a previous rounding.) Doing this repeatedly would cause unbounded growth in val. So fix the math. Here's what was wrong with the conversion: we essentially computed (eliding seconds) jiffies = usec * (NSEC_PER_USEC/TICK_NSEC) by using scaling arithmetic, which took the best approximation of NSEC_PER_USEC/TICK_NSEC with denominator of 2^USEC_JIFFIE_SC = x/(2^USEC_JIFFIE_SC), and computed: jiffies = (usec * x) >> USEC_JIFFIE_SC and rounded this calculation up in the intermediate form (since we can't necessarily exactly represent TICK_NSEC in usec.) But the scaling arithmetic is a (very slight) *over*approximation of the true value; that is, instead of dividing by (1 usec/ 1 jiffie), we effectively divided by (1 usec/1 jiffie)-epsilon (rounding down). This would normally be fine, but we want to round timeouts up, and we did so by adding 2^USEC_JIFFIE_SC - 1 before the shift; this would be fine if our division was exact, but dividing this by the slightly smaller factor was equivalent to adding just _over_ 1 to the final result (instead of just _under_ 1, as desired.) In particular, with HZ=1000, we consistently computed that 10000 usec was 11 jiffies; the same was true for any exact multiple of TICK_NSEC. We could possibly still round in the intermediate form, adding something less than 2^USEC_JIFFIE_SC - 1, but easier still is to convert usec->nsec, round in nanoseconds, and then convert using time*spec*_to_jiffies. This adds one constant multiplication, and is not observably slower in microbenchmarks on recent x86 hardware. Tested: the following program: int main() { struct itimerval zero = {{0, 0}, {0, 0}}; /* Initially set to 10 ms. */ struct itimerval initial = zero; initial.it_interval.tv_usec = 10000; setitimer(ITIMER_PROF, &initial, NULL); /* Save and restore several times. */ for (size_t i = 0; i < 10; ++i) { struct itimerval prev; setitimer(ITIMER_PROF, &zero, &prev); /* on old kernels, this goes up by TICK_USEC every iteration */ printf("previous value: %ld %ld %ld %ld\n", prev.it_interval.tv_sec, prev.it_interval.tv_usec, prev.it_value.tv_sec, prev.it_value.tv_usec); setitimer(ITIMER_PROF, &prev, NULL); } return 0; } Cc: stable@vger.kernel.org Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Paul Turner <pjt@google.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Reviewed-by: Paul Turner <pjt@google.com> Reported-by: Aaron Jacobs <jacobsa@google.com> Signed-off-by: Andrew Hunter <ahh@google.com> [jstultz: Tweaked to apply to 3.17-rc] Signed-off-by: John Stultz <john.stultz@linaro.org>
2014-07-23time: Export nsecs_to_jiffies()Thomas Gleixner
Required for moving drivers to the nanosecond based interfaces. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2014-07-23time: Consolidate the time accessor prototypesThomas Gleixner
Right now we have time related prototypes in 3 different header files. Move it to a single timekeeping header file and move the core internal stuff into a core private header. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2014-07-23time: More core infrastructure for timespec64John Stultz
Helper and conversion functions for timespec64. Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2014-06-23time/timers: Move all time(r) related files into kernel/timeThomas Gleixner
Except for Kconfig.HZ. That needs a separate treatment. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>