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* Merge latest changes from google kernel/common.gitRoman Shaposhnikov2012-06-132-3/+3
| | | | | | | Kernel version updated to 3.0.31 Change-Id: Ifbd7150801f3beeec9cbaa566f249d8019ef9348 Signed-off-by: Roman Shaposhnikov <x0166637@ti.com>
* Merge branch 'linux-3.0.18' into p-android-omap-3.0Dan Murphy2012-02-024-4/+8
|\ | | | | | | | | | | | | | | | | | | | | Conflicts: arch/arm/mach-omap2/smartreflex.c drivers/i2c/busses/i2c-omap.c drivers/usb/host/ehci.h drivers/usb/musb/musb_core.c fs/proc/base.c Signed-off-by: Dan Murphy <dmurphy@ti.com>
| * Revert "clockevents: Set noop handler in clockevents_exchange_device()"Linus Torvalds2012-01-031-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 3b87487ac5008072f138953b07505a7e3493327f upstream. This reverts commit de28f25e8244c7353abed8de0c7792f5f883588c. It results in resume problems for various people. See for example http://thread.gmane.org/gmane.linux.kernel/1233033 http://thread.gmane.org/gmane.linux.kernel/1233389 http://thread.gmane.org/gmane.linux.kernel/1233159 http://thread.gmane.org/gmane.linux.kernel/1227868/focus=1230877 and the fedora and ubuntu bug reports https://bugzilla.redhat.com/show_bug.cgi?id=767248 https://bugs.launchpad.net/ubuntu/+source/linux/+bug/904569 which got bisected down to the stable version of this commit. Reported-by: Jonathan Nieder <jrnieder@gmail.com> Reported-by: Phil Miller <mille121@illinois.edu> Reported-by: Philip Langdale <philipl@overt.org> Reported-by: Tim Gardner <tim.gardner@canonical.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * alarmtimers: Fix time comparisonThomas Gleixner2011-12-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit c9c024b3f3e07d087974db4c0dc46217fff3a6c0 upstream. The expiry function compares the timer against current time and does not expire the timer when the expiry time is >= now. That's wrong. If the timer is set for now, then it must expire. Make the condition expiry > now for breaking out the loop. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * clockevents: Set noop handler in clockevents_exchange_device()Thomas Gleixner2011-12-091-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | commit de28f25e8244c7353abed8de0c7792f5f883588c upstream. If a device is shutdown, then there might be a pending interrupt, which will be processed after we reenable interrupts, which causes the original handler to be run. If the old handler is the (broadcast) periodic handler the shutdown state might hang the kernel completely. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * clocksource: Fix bug with max_deferment margin calculationYang Honggang (Joseph)2011-12-091-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | commit b1f919664d04a8d0ba29cb76673c7ca3325a2006 upstream. In order to leave a margin of 12.5% we should >> 3 not >> 5. Signed-off-by: Yang Honggang (Joseph) <eagle.rtlinux@gmail.com> [jstultz: Modified commit subject] Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * tick-broadcast: Stop active broadcast device when replacing itThomas Gleixner2011-12-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | commit c1be84309c58b1e7c6d626e28fba41a22b364c3d upstream. When a better rated broadcast device is installed, then the current active device is not disabled, which results in two running broadcast devices. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * timekeeping: add arch_offset hook to ktime_get functionsHector Palacios2011-12-091-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit d004e024058a0eaca097513ce62cbcf978913e0a upstream. ktime_get and ktime_get_ts were calling timekeeping_get_ns() but later they were not calling arch_gettimeoffset() so architectures using this mechanism returned 0 ns when calling these functions. This happened for example when running Busybox's ping which calls syscall(__NR_clock_gettime, CLOCK_MONOTONIC, ts) which eventually calls ktime_get. As a result the returned ping travel time was zero. Signed-off-by: Hector Palacios <hector.palacios@digi.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | Fix "time: Catch invalid timespec sleep values in ↵Arve Hjønnevåg2011-11-291-1/+1
| | | | | | | | | | | | __timekeeping_inject_sleeptime" to compile on 3.0 Change-Id: I1225f279cda04dedbfb7f853f6b58f1032bd6d2b
* | time: Catch invalid timespec sleep values in __timekeeping_inject_sleeptimeJohn Stultz2011-11-291-0/+6
| | | | | | | | | | | | | | | | | | Arve suggested making sure we catch possible negative sleep time intervals that could be passed into timekeeping_inject_sleeptime. CC: Arve Hjønnevåg <arve@android.com> CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
* | Merge branch 'linux-omap-3.0' into android-omap-3.0Colin Cross2011-10-301-24/+0
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| * | Revert "clockevents: Provide interface to reconfigure an active clock event ↵Colin Cross2011-10-291-24/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | device" This reverts commit 0da4892a9f99efd4c97079dcda30a79313b0eb20. This was an old version of the patch, an improved version is already in v3.0. Change-Id: Ib88e3d0b1b1f439de8480e1990fba232352d2510
* | | Merge branch 'linux-omap-3.0' into android-omap-3.0Colin Cross2011-10-271-5/+13
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| * | Merge commit 'v3.0.8' into linux-omap-3.0Colin Cross2011-10-271-5/+13
| |\ \ | | |/ | | | | | | | | | | | | | | | | | | | | | Conflicts: drivers/tty/serial/omap-serial.c drivers/usb/musb/musb_gadget.c sound/soc/omap/omap-mcbsp.c Change-Id: Ic31b7266dda3ac8483f737272874ebf4725b5fe3
| | * alarmtimers: Avoid possible denial of service with high freq periodic timersJohn Stultz2011-10-031-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 6af7e471e5a7746b8024d70b4363d3dfe41d36b8 upstream. Its possible to jam up the alarm timers by setting very small interval timers, which will cause the alarmtimer subsystem to spend all of its time firing and restarting timers. This can effectivly lock up a box. A deeper fix is needed, closely mimicking the hrtimer code, but for now just cap the interval to 100us to avoid userland hanging the system. CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| | * alarmtimers: Memset itimerspec passed into alarm_timer_getJohn Stultz2011-10-031-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit ea7802f630d356acaf66b3c0b28c00a945fc35dc upstream. Following common_timer_get, zero out the itimerspec passed in. CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| | * alarmtimers: Avoid possible null pointer traversalJohn Stultz2011-10-031-5/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 971c90bfa2f0b4fe52d6d9002178d547706f1343 upstream. We don't check if old_setting is non null before assigning it, so correct this. CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | Merge commit 'v3.0-rc5' into linux-omap-3.0Colin Cross2011-06-291-70/+88
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* | | Merge branch 'android-3.0' into android-omap-3.0Colin Cross2011-06-291-70/+88
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| * \ \ Merge commit 'v3.0-rc5' into android-3.0Colin Cross2011-06-292-81/+101
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| | * | alarmtimers: Return -ENOTSUPP if no RTC device is presentJohn Stultz2011-06-211-1/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Toralf Förster and Richard Weinberger noted that if there is no RTC device, the alarm timers core prints out an annoying "ALARM timers will not wake from suspend" message. This warning has been removed in a previous patch, however the issue still remains: The original idea was to support alarm timers even if there was no rtc device, as long as the system didn't go into suspend. However, after further consideration, communicating to the application that alarmtimers are not fully functional seems like the better solution. So this patch makes it so we return -ENOTSUPP to any posix _ALARM clockid calls if there is no backing RTC device on the system. Further this changes the behavior where when there is no rtc device we will check for one on clock_getres, clock_gettime, timer_create, and timer_nsleep instead of on suspend. CC: Toralf Förster <toralf.foerster@gmx.de> CC: Richard Weinberger <richard@nod.at CC: Peter Zijlstra <peterz@infradead.org> CC: Thomas Gleixner <tglx@linutronix.de> Reported-by: Toralf Förster <toralf.foerster@gmx.de> Reported by: Richard Weinberger <richard@nod.at> Signed-off-by: John Stultz <john.stultz@linaro.org>
| | * | alarmtimers: Handle late rtc module loadingJohn Stultz2011-06-211-70/+67
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The alarmtimers code currently picks a rtc device to use at late init time. However, if your rtc driver is loaded as a module, it may be registered after the alarmtimers late init code, leaving the alarmtimers nonfunctional. This patch moves the the rtcdevice selection to when we actually try to use it, allowing us to make use of rtc modules that may have been loaded at any point since bootup. CC: Thomas Gleixner <tglx@linutronix.de> CC: Meelis Roos <mroos@ut.ee> Reported-by: Meelis Roos <mroos@ut.ee> Signed-off-by: John Stultz <john.stultz@linaro.org>
* | | | Merge branch 'linux-omap-3.0' into android-omap-3.0Colin Cross2011-06-221-11/+13
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| * | | Merge commit 'v3.0-rc4' into linux-omap-3.0Colin Cross2011-06-221-11/+13
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| | * | clocksource: Make watchdog robust vs. interruptionThomas Gleixner2011-06-161-11/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The clocksource watchdog code is interruptible and it has been observed that this can trigger false positives which disable the TSC. The reason is that an interrupt storm or a long running interrupt handler between the read of the watchdog source and the read of the TSC brings the two far enough apart that the delta is larger than the unstable treshold. Move both reads into a short interrupt disabled region to avoid that. Reported-and-tested-by: Vernon Mauery <vernux@us.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@kernel.org
* | | | Merge branch 'android-3.0' into android-omap-3.0Colin Cross2011-06-141-1/+1
|\ \ \ \ | |/ / / |/| | / | | |/ | |/| | | | | | | | | | | | | | | | Conflicts: Documentation/cpu-freq/governors.txt drivers/cpufreq/Kconfig drivers/cpufreq/Makefile include/linux/cpufreq.h Change-Id: I3df552521b721b7590883071633873caba33cffd
| * | HACK: time: Disable alarmtimerColin Cross2011-06-141-1/+1
| |/ | | | | | | | | | | | | | | kernel/time/alarmtimer.c conflicts with drivers/rtc/alarm.c, disable it for now. Change-Id: I6cdb3b885828d45836a54971adf16143039b0a0e Signed-off-by: Colin Cross <ccross@android.com>
* | Merge branch 'linux-omap-pm-3.0' into linux-omap-3.0Colin Cross2011-06-141-0/+24
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| * clockevents: Provide interface to reconfigure an active clock event deviceThomas Gleixner2011-06-131-0/+24
| | | | | | | | | | | | | | | | | | Some ARM SoCs have clock event devices which have their frequency modified due to frequency scaling. Provide an interface which allows to reconfigure an active device. After reconfiguration reprogram the current pending event. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | clockevents: Handle empty cpumask gracefullyThomas Gleixner2011-06-031-1/+4
|/ | | | | | | | | | | | | | | | For UP it's stupid to request an initialized cpumask for the clock event devices. Though we need the mask set even on UP to avoid a horrible ifdeffery especially in the broadcast code. For SMP we can at least try to survive with a warning and set the cpumask of the cpu we're running on. That gives a decent chance to bring the machine up and retrieve the debug info. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Walleij <linus.walleij@linaro.org Cc: Lee Jones <lee.jones@linaro.org> Cc: Russell King - ARM Linux <linux@arm.linux.org.uk> Cc: Stephen Boyd <sboyd@codeaurora.org>
* hrtimers: Avoid touching inactive timer basesThomas Gleixner2011-05-231-2/+2
| | | | | | | | Instead of iterating over all possible timer bases avoid it by marking the active bases in the cpu base. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Peter Zijlstra <peterz@infradead.org>
* Merge branch 'timers/urgent' into timers/coreThomas Gleixner2011-05-203-22/+96
|\ | | | | | | | | | | | | Reason: Get upstream fixes and kfree_rcu which is necessary for a follow up patch. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * clockevents/source: Use u64 to make 32bit happyThomas Gleixner2011-05-202-2/+2
| | | | | | | | | | | | unsigned long is not 64bit on 32bit machine. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * Merge branch 'timers-core-for-linus' of ↵Linus Torvalds2011-05-193-4/+748
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: hrtimer: Make lookup table const RTC: Disable CONFIG_RTC_CLASS from being built as a module timers: Fix alarmtimer build issues when CONFIG_RTC_CLASS=n timers: Remove delayed irqwork from alarmtimers implementation timers: Improve alarmtimer comments and minor fixes timers: Posix interface for alarm-timers timers: Introduce in-kernel alarm-timer interface timers: Add rb_init_node() to allow for stack allocated rb nodes time: Add timekeeping_inject_sleeptime
| * \ Merge branch 'timers-clockevents-for-linus' of ↵Linus Torvalds2011-05-192-19/+83
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-clockevents-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: hpet: Cleanup the clockevents init and register code x86: Convert PIT to clockevents_config_and_register() clockevents: Provide interface to reconfigure an active clock event device clockevents: Provide combined configure and register function clockevents: Restructure clock_event_device members clocksource: Get rid of the hardcoded 5 seconds sleep time limit clocksource: Restructure clocksource struct members
| | * | clockevents: Provide interface to reconfigure an active clock event deviceThomas Gleixner2011-05-191-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some ARM SoCs have clock event devices which have their frequency modified due to frequency scaling. Provide an interface which allows to reconfigure an active device. After reconfiguration reprogram the current pending event. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: LAK <linux-arm-kernel@lists.infradead.org> Cc: John Stultz <john.stultz@linaro.org> Acked-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Ingo Molnar <mingo@elte.hu> Link: http://lkml.kernel.org/r/%3C20110518210136.437459958%40linutronix.de%3E
| | * | clockevents: Provide combined configure and register functionThomas Gleixner2011-05-191-0/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All clockevent devices have the same open coded initialization functions. Provide an interface which does all necessary initialization in the core code. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Reviewed-by: Ingo Molnar <mingo@elte.hu> Link: http://lkml.kernel.org/r/%3C20110518210136.331975870%40linutronix.de%3E
| | * | clocksource: Get rid of the hardcoded 5 seconds sleep time limitThomas Gleixner2011-05-191-19/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Slow clocksources can have a way longer sleep time than 5 seconds and even fast ones can easily cope with 600 seconds and still maintain proper accuracy. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Reviewed-by: Ingo Molnar <mingo@elte.hu> Link: http://lkml.kernel.org/r/%3C20110518210136.109811585%40linutronix.de%3E
| * | | tick: Clear broadcast active bit when switching to oneshotThomas Gleixner2011-05-161-1/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The first cpu which switches from periodic to oneshot mode switches also the broadcast device into oneshot mode. The broadcast device serves as a backup for per cpu timers which stop in deeper C-states. To avoid starvation of the cpus which might be in idle and depend on broadcast mode it marks the other cpus as broadcast active and sets the brodcast expiry value of those cpus to the next tick. The oneshot mode broadcast bit for the other cpus is sticky and gets only cleared when those cpus exit idle. If a cpu was not idle while the bit got set in consequence the bit prevents that the broadcast device is armed on behalf of that cpu when it enters idle for the first time after it switched to oneshot mode. In most cases that goes unnoticed as one of the other cpus has usually a timer pending which keeps the broadcast device armed with a short timeout. Now if the only cpu which has a short timer active has the bit set then the broadcast device will not be armed on behalf of that cpu and will fire way after the expected timer expiry. In the case of Christians bug report it took ~145 seconds which is about half of the wrap around time of HPET (the limit for that device) due to the fact that all other cpus had no timers armed which expired before the 145 seconds timeframe. The solution is simply to clear the broadcast active bit unconditionally when a cpu switches to oneshot mode after the first cpu switched the broadcast device over. It's not idle at that point otherwise it would not be executing that code. [ I fundamentally hate that broadcast crap. Why the heck thought some folks that when going into deep idle it's a brilliant concept to switch off the last device which brings the cpu back from that state? ] Thanks to Christian for providing all the valuable debug information! Reported-and-tested-by: Christian Hoffmann <email@christianhoffmann.info> Cc: John Stultz <johnstul@us.ibm.com> Link: http://lkml.kernel.org/r/%3Calpine.LFD.2.02.1105161105170.3078%40ionos%3E Cc: stable@kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | clocksource: Install completely before selectingjohn stultz2011-05-051-2/+2
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Christian Hoffmann reported that the command line clocksource override with acpi_pm timer fails: Kernel command line: <SNIP> clocksource=acpi_pm hpet clockevent registered Switching to clocksource hpet Override clocksource acpi_pm is not HRT compatible. Cannot switch while in HRT/NOHZ mode. The watchdog code is what enables CLOCK_SOURCE_VALID_FOR_HRES, but we actually end up selecting the clocksource before we enqueue it into the watchdog list, so that's why we see the warning and fail to switch to acpi_pm timer as requested. That's particularly bad when we want to debug timekeeping related problems in early boot. Put the selection call last. Reported-by: Christian Hoffmann <email@christianhoffmann.info> Signed-off-by: John Stultz <johnstul@us.ibm.com> Cc: stable@kernel.org # 32... Link: http://lkml.kernel.org/r/%3C1304558210.2943.24.camel%40work-vm%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | | clockevents: Move C3 stop test outside lockAndi Kleen2011-05-051-7/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Avoid taking broadcast_lock in the idle path for systems where the timer doesn't stop in C3. [ tglx: Removed the stale label and added comment ] Signed-off-by: Andi Kleen <ak@linux.intel.com> Cc: Dave Kleikamp <dkleikamp@gmail.com> Cc: Chris Mason <chris.mason@oracle.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: lenb@kernel.org Cc: paulmck@us.ibm.com Link: http://lkml.kernel.org/r/%3C20110504234806.GF2925%40one.firstfloor.org%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | | alarmtimer: Drop device refcount after rtc_open()Thomas Gleixner2011-05-041-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | class_find_device() takes a refcount on the rtc device. rtc_open() takes another one, so we can drop it after the rtc_open() call. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org>
* | | alarmtimer: Check return value of class_find_device()Thomas Gleixner2011-05-041-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | alarmtimer_late_init() uses class_find_device() to find a alarm capable rtc device. The match callback stores a pointer to the name in the char pointer handed in from the call site. alarmtimer_late_init() checks the char pointer for NULL, but the pointer is on the stack and not initialized to NULL before the call. So it can have random content when the match function did not identify a device, which leads to random access in the following rtc_open() call where the pointer is dereferenced Instead of relying on the char pointer, check the return value of class_find_device. If a device is found then the name pointer is valid as well. Reported-by: Ingo Molnar <mingo@elte.hu> Cc: John Stultz <john.stultz@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | | timerfd: Allow timers to be cancelled when clock was setThomas Gleixner2011-05-021-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some applications must be aware of clock realtime being set backward. A simple example is a clock applet which arms a timer for the next minute display. If clock realtime is set backward then the applet displays a stale time for the amount of time which the clock was set backwards. Due to that applications poll the time because we don't have an interface. Extend the timerfd interface by adding a flag which puts the timer onto a different internal realtime clock. All timers on this clock are expired whenever the clock was set. The timerfd core records the monotonic offset when the timer is created. When the timer is armed, then the current offset is compared to the previous recorded offset. When it has changed, then timerfd_settime returns -ECANCELED. When a timer is read the offset is compared and if it changed -ECANCELED returned to user space. Periodic timers are not rearmed in the cancelation case. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <johnstul@us.ibm.com> Cc: Chris Friesen <chris.friesen@genband.com> Tested-by: Kay Sievers <kay.sievers@vrfy.org> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Davide Libenzi <davidel@xmailserver.org> Reviewed-by: Alexander Shishkin <virtuoso@slind.org> Link: http://lkml.kernel.org/r/%3Calpine.LFD.2.02.1104271359580.3323%40ionos%3E Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | | hrtimers: Prepare for cancel on clock was set timersThomas Gleixner2011-05-021-1/+1
| |/ |/| | | | | | | | | | | | | Make clock_was_set() unconditional and rename hres_timers_resume to hrtimers_resume. This is a preparatory patch for hrtimers which are cancelled when clock realtime was set. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | timers: Fix alarmtimer build issues when CONFIG_RTC_CLASS=nJohn Stultz2011-05-021-2/+18
| | | | | | | | | | | | | | | | | | | | Ingo pointed out that the alarmtimers won't build if CONFIG_RTC_CLASS=n. This patch adds proper ifdefs to the alarmtimer code to disable the rtc usage if it is not built in. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | timers: Remove delayed irqwork from alarmtimers implementationJohn Stultz2011-04-281-23/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Thomas asked about the delayed irq work in the alarmtimers code, and I realized that it was a legacy from when the alarmtimer base lock was a mutex (due to concerns that we'd be interacting with the RTC device, which is protected by mutexes). Since the alarmtimer base is now protected by a spinlock, we can simply execute alarmtimer functions directly from the hrtimer callback. Should any future alarmtimer functions sleep, they can simply manage scheduling any delayed work themselves. CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
* | timers: Improve alarmtimer comments and minor fixesJohn Stultz2011-04-281-40/+27
| | | | | | | | | | | | | | | | This patch addresses a number of minor comment improvements and other minor issues from Thomas' review of the alarmtimers code. CC: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
* | timers: Posix interface for alarm-timersJohn Stultz2011-04-261-0/+330
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch exposes alarm-timers to userland via the posix clock and timers interface, using two new clockids: CLOCK_REALTIME_ALARM and CLOCK_BOOTTIME_ALARM. Both clockids behave identically to CLOCK_REALTIME and CLOCK_BOOTTIME, respectively, but timers set against the _ALARM suffixed clockids will wake the system if it is suspended. Some background can be found here: https://lwn.net/Articles/429925/ The concept for Alarm-timers was inspired by the Android Alarm driver (by Arve Hjønnevåg) found in the Android kernel tree. See: http://android.git.kernel.org/?p=kernel/common.git;a=blob;f=drivers/rtc/alarm.c;h=1250edfbdf3302f5e4ea6194847c6ef4bb7beb1c;hb=android-2.6.36 While the in-kernel interface is pretty similar between alarm-timers and Android alarm driver, the user-space interface for the Android alarm driver is via ioctls to a new char device. As mentioned above, I've instead chosen to export this functionality via the posix interface, as it seemed a little simpler and avoids creating duplicate interfaces to things like CLOCK_REALTIME and CLOCK_MONOTONIC under alternate names (ie:ANDROID_ALARM_RTC and ANDROID_ALARM_SYSTEMTIME). The semantics of the Android alarm driver are different from what this posix interface provides. For instance, threads other then the thread waiting on the Android alarm driver are able to modify the alarm being waited on. Also this interface does not allow the same wakelock semantics that the Android driver provides (ie: kernel takes a wakelock on RTC alarm-interupt, and holds it through process wakeup, and while the process runs, until the process either closes the char device or calls back in to wait on a new alarm). One potential way to implement similar semantics may be via the timerfd infrastructure, but this needs more research. There may also need to be some sort of sysfs system level policy hooks that allow alarm timers to be disabled to keep them from firing at inappropriate times (ie: laptop in a well insulated bag, mid-flight). CC: Arve Hjønnevåg <arve@android.com> CC: Thomas Gleixner <tglx@linutronix.de> CC: Alessandro Zummo <a.zummo@towertech.it> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
* | timers: Introduce in-kernel alarm-timer interfaceJohn Stultz2011-04-262-1/+376
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This provides the in kernel interface and infrastructure for alarm-timers. Alarm-timers are a hybrid style timer, similar to hrtimers, but when the system is suspended, the RTC device is set to fire and wake the system for when the soonest alarm-timer expires. The concept for Alarm-timers was inspired by the Android Alarm driver (by Arve Hjønnevåg) found in the Android kernel tree. See: http://android.git.kernel.org/?p=kernel/common.git;a=blob;f=drivers/rtc/alarm.c;h=1250edfbdf3302f5e4ea6194847c6ef4bb7beb1c;hb=android-2.6.36 This in-kernel interface should be fairly compatible with the Android alarm driver in-kernel interface, but has the advantage of utilizing the new RTC timerqueue code instead of doing direct RTC manipulation. CC: Arve Hjønnevåg <arve@android.com> CC: Thomas Gleixner <tglx@linutronix.de> CC: Alessandro Zummo <a.zummo@towertech.it> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
generated by cgit v1.1 at 2025-02-10 09:18:36 +0000