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* Merge tag 'clk-for-linus-3.20' of ↵Linus Torvalds2015-02-211-0/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.linaro.org/people/mike.turquette/linux Pull clock framework updates from Mike Turquette: "The clock framework changes contain the usual driver additions, enhancements and fixes mostly for ARM32, ARM64, MIPS and Power-based devices. Additionally the framework core underwent a bit of surgery with two major changes: - The boundary between the clock core and clock providers (e.g clock drivers) is now more well defined with dedicated provider helper functions. struct clk no longer maps 1:1 with the hardware clock but is a true per-user cookie which helps us tracker users of hardware clocks and debug bad behavior. - The addition of rate constraints for clocks. Rate ranges are now supported which are analogous to the voltage ranges in the regulator framework. Unfortunately these changes to the core created some breakeage. We think we fixed it all up but for this reason there are lots of last minute commits trying to undo the damage" * tag 'clk-for-linus-3.20' of git://git.linaro.org/people/mike.turquette/linux: (113 commits) clk: Only recalculate the rate if needed Revert "clk: mxs: Fix invalid 32-bit access to frac registers" clk: qoriq: Add support for the platform PLL powerpc/corenet: Enable CLK_QORIQ clk: Replace explicit clk assignment with __clk_hw_set_clk clk: Add __clk_hw_set_clk helper function clk: Don't dereference parent clock if is NULL MIPS: Alchemy: Remove bogus args from alchemy_clk_fgcs_detr clkdev: Always allocate a struct clk and call __clk_get() w/ CCF clk: shmobile: div6: Avoid division by zero in .round_rate() clk: mxs: Fix invalid 32-bit access to frac registers clk: omap: compile legacy omap3 clocks conditionally clkdev: Export clk_register_clkdev clk: Add rate constraints to clocks clk: remove clk-private.h pci: xgene: do not use clk-private.h arm: omap2+ remove dead clock code clk: Make clk API return per-user struct clk instances clk: tegra: Define PLLD_DSI and remove dsia(b)_mux clk: tegra: Add support for the Tegra132 CAR IP block ...
| * powerpc: call of_clk_init() from time_init()Kevin Hao2015-01-201-0/+5
| | | | | | | | | | | | | | | | | | | | So the boards which has COMMON_CLK enabled don't have to invoke this in its board specific file. Signed-off-by: Kevin Hao <haokexin@gmail.com> Acked-by: Scott Wood <scottwood@freescale.com> Acked-by: Michael Turquette <mturquette@linaro.org> Signed-off-by: Michael Turquette <mturquette@linaro.org>
* | powerpc: add running_clock for powerpc to prevent spurious softlockup warningsCyril Bur2015-02-121-0/+32
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On POWER8 virtualised kernels the VTB register can be read to have a view of time that only increases while the guest is running. This will prevent guests from seeing time jump if a guest is paused for significant amounts of time. On POWER7 and below virtualised kernels stolen time is subtracted from local_clock as a best effort approximation. This will not eliminate spurious warnings in the case of a suspended guest but may reduce the occurance in the case of softlockups due to host over commit. Bare metal kernels should avoid reading the VTB as KVM does not restore sane values when not executing, the approxmation is fine as host kernels won't observe any stolen time. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Cyril Bur <cyrilbur@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Andrew Jones <drjones@redhat.com> Acked-by: Don Zickus <dzickus@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Ulrich Obergfell <uobergfe@redhat.com> Cc: chai wen <chaiw.fnst@cn.fujitsu.com> Cc: Fabian Frederick <fabf@skynet.be> Cc: Aaron Tomlin <atomlin@redhat.com> Cc: Ben Zhang <benzh@chromium.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* rtc/tpo: Driver to support rtc and wakeup on PowerNV platformNeelesh Gupta2014-11-171-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The patch implements the OPAL rtc driver that binds with the rtc driver subsystem. The driver uses the platform device infrastructure to probe the rtc device and register it to rtc class framework. The 'wakeup' is supported depending upon the property 'has-tpo' present in the OF node. It provides a way to load the generic rtc driver in in the absence of an OPAL driver. The patch also moves the existing OPAL rtc get/set time interfaces to the new driver and exposes the necessary OPAL calls using EXPORT_SYMBOL_GPL. Test results: ------------- Host: [root@tul169p1 ~]# ls -l /sys/class/rtc/ total 0 lrwxrwxrwx 1 root root 0 Oct 14 03:07 rtc0 -> ../../devices/opal-rtc/rtc/rtc0 [root@tul169p1 ~]# cat /sys/devices/opal-rtc/rtc/rtc0/time 08:10:07 [root@tul169p1 ~]# echo `date '+%s' -d '+ 2 minutes'` > /sys/class/rtc/rtc0/wakealarm [root@tul169p1 ~]# cat /sys/class/rtc/rtc0/wakealarm 1413274345 [root@tul169p1 ~]# FSP: $ smgr mfgState standby $ rtim timeofday System time is valid: 2014/10/14 08:12:04.225115 $ smgr mfgState ipling $ CC: devicetree@vger.kernel.org CC: tglx@linutronix.de CC: rtc-linux@googlegroups.com CC: a.zummo@towertech.it Signed-off-by: Neelesh Gupta <neelegup@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc: Replace __get_cpu_var usesChristoph Lameter2014-11-031-11/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This still has not been merged and now powerpc is the only arch that does not have this change. Sorry about missing linuxppc-dev before. V2->V2 - Fix up to work against 3.18-rc1 __get_cpu_var() is used for multiple purposes in the kernel source. One of them is address calculation via the form &__get_cpu_var(x). This calculates the address for the instance of the percpu variable of the current processor based on an offset. Other use cases are for storing and retrieving data from the current processors percpu area. __get_cpu_var() can be used as an lvalue when writing data or on the right side of an assignment. __get_cpu_var() is defined as : __get_cpu_var() always only does an address determination. However, store and retrieve operations could use a segment prefix (or global register on other platforms) to avoid the address calculation. this_cpu_write() and this_cpu_read() can directly take an offset into a percpu area and use optimized assembly code to read and write per cpu variables. This patch converts __get_cpu_var into either an explicit address calculation using this_cpu_ptr() or into a use of this_cpu operations that use the offset. Thereby address calculations are avoided and less registers are used when code is generated. At the end of the patch set all uses of __get_cpu_var have been removed so the macro is removed too. The patch set includes passes over all arches as well. Once these operations are used throughout then specialized macros can be defined in non -x86 arches as well in order to optimize per cpu access by f.e. using a global register that may be set to the per cpu base. Transformations done to __get_cpu_var() 1. Determine the address of the percpu instance of the current processor. DEFINE_PER_CPU(int, y); int *x = &__get_cpu_var(y); Converts to int *x = this_cpu_ptr(&y); 2. Same as #1 but this time an array structure is involved. DEFINE_PER_CPU(int, y[20]); int *x = __get_cpu_var(y); Converts to int *x = this_cpu_ptr(y); 3. Retrieve the content of the current processors instance of a per cpu variable. DEFINE_PER_CPU(int, y); int x = __get_cpu_var(y) Converts to int x = __this_cpu_read(y); 4. Retrieve the content of a percpu struct DEFINE_PER_CPU(struct mystruct, y); struct mystruct x = __get_cpu_var(y); Converts to memcpy(&x, this_cpu_ptr(&y), sizeof(x)); 5. Assignment to a per cpu variable DEFINE_PER_CPU(int, y) __get_cpu_var(y) = x; Converts to __this_cpu_write(y, x); 6. Increment/Decrement etc of a per cpu variable DEFINE_PER_CPU(int, y); __get_cpu_var(y)++ Converts to __this_cpu_inc(y) Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> CC: Paul Mackerras <paulus@samba.org> Signed-off-by: Christoph Lameter <cl@linux.com> [mpe: Fix build errors caused by set/or_softirq_pending(), and rework assignment in __set_breakpoint() to use memcpy().] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc: Make a bunch of things staticAnton Blanchard2014-09-251-2/+2
| | | | | Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* powerpc: Move more symbol exports next to function definitionsAnton Blanchard2014-09-251-0/+1
| | | | | Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* clocksource: Get rid of cycle_lastThomas Gleixner2014-07-231-2/+2
| | | | | | | | | cycle_last was added to the clocksource to support the TSC validation. We moved that to the core code, so we can get rid of the extra copy. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
* powerpc: fix typo 'CONFIG_PMAC'Paul Bolle2014-06-111-1/+1
| | | | | | | | | | Commit b0d278b7d3ae ("powerpc/perf_event: Reduce latency of calling perf_event_do_pending") added a check for CONFIG_PMAC were a check for CONFIG_PPC_PMAC was clearly intended. Fixes: b0d278b7d3ae ("powerpc/perf_event: Reduce latency of calling perf_event_do_pending") Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: irq work racing with timer interrupt can result in timer interrupt hangAnton Blanchard2014-05-121-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I am seeing an issue where a CPU running perf eventually hangs. Traces show timer interrupts happening every 4 seconds even when a userspace task is running on the CPU. /proc/timer_list also shows pending hrtimers have not run in over an hour, including the scheduler. Looking closer, decrementers_next_tb is getting set to 0xffffffffffffffff, and at that point we will never take a timer interrupt again. In __timer_interrupt() we set decrementers_next_tb to 0xffffffffffffffff and rely on ->event_handler to update it: *next_tb = ~(u64)0; if (evt->event_handler) evt->event_handler(evt); In this case ->event_handler is hrtimer_interrupt. This will eventually call back through the clockevents code with the next event to be programmed: static int decrementer_set_next_event(unsigned long evt, struct clock_event_device *dev) { /* Don't adjust the decrementer if some irq work is pending */ if (test_irq_work_pending()) return 0; __get_cpu_var(decrementers_next_tb) = get_tb_or_rtc() + evt; If irq work came in between these two points, we will return before updating decrementers_next_tb and we never process a timer interrupt again. This looks to have been introduced by 0215f7d8c53f (powerpc: Fix races with irq_work). Fix it by removing the early exit and relying on code later on in the function to force an early decrementer: /* We may have raced with new irq work */ if (test_irq_work_pending()) set_dec(1); Signed-off-by: Anton Blanchard <anton@samba.org> Cc: stable@vger.kernel.org # 3.14+ Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* cpuidle/powernv: Add "Fast-Sleep" CPU idle statePreeti U Murthy2014-03-051-1/+3
| | | | | | | | | | | Fast sleep is one of the deep idle states on Power8 in which local timers of CPUs stop. On PowerPC we do not have an external clock device which can handle wakeup of such CPUs. Now that we have the support in the tick broadcast framework for archs that do not sport such a device and the low level support for fast sleep, enable it in the cpuidle framework on PowerNV. Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: Split timer_interrupt() into timer handling and interrupt handling ↵Preeti U Murthy2014-03-051-35/+46
| | | | | | | | | | | | | | | | routines Split timer_interrupt(), which is the local timer interrupt handler on ppc into routines called during regular interrupt handling and __timer_interrupt(), which takes care of running local timers and collecting time related stats. This will enable callers interested only in running expired local timers to directly call into __timer_interupt(). One of the use cases of this is the tick broadcast IPI handling in which the sleeping CPUs need to handle the local timers that have expired. Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: Implement tick broadcast IPI as a fixed IPI messageSrivatsa S. Bhat2014-03-051-0/+5
| | | | | | | | | | | | | | | | | | | For scalability and performance reasons, we want the tick broadcast IPIs to be handled as efficiently as possible. Fixed IPI messages are one of the most efficient mechanisms available - they are faster than the smp_call_function mechanism because the IPI handlers are fixed and hence they don't involve costly operations such as adding IPI handlers to the target CPU's function queue, acquiring locks for synchronization etc. Luckily we have an unused IPI message slot, so use that to implement tick broadcast IPIs efficiently. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> [Functions renamed to tick_broadcast* and Changelog modified by Preeti U. Murthy<preeti@linux.vnet.ibm.com>] Signed-off-by: Preeti U. Murthy <preeti@linux.vnet.ibm.com> Acked-by: Geoff Levand <geoff@infradead.org> [For the PS3 part] Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: Fix races with irq_workBenjamin Herrenschmidt2014-01-151-0/+11
| | | | | | | | | | | | If we set irq_work on a processor and immediately afterward, before the irq work has a chance to be processed, we change the decrementer value, we can seriously delay the handling of that irq_work. Fix it by checking in a few places for pending irq work, first before changing the decrementer in decrementer_set_next_event() and after changing it in the same function and in timer_interrupt(). Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: Make irq_stat.timers_irqs counting more specificfan.du2013-12-021-1/+2
| | | | | | | | | | Current irq_stat.timers_irqs counting doesn't discriminate timer event handler and other timer interrupt(like arch_irq_work_raise). Sometimes we need to know exactly how much interrupts timer event handler fired, so let's be more specific on this. Signed-off-by: Fan Du <fan.du@windriver.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc/pseries: Duplicate dtl entries sometimes sent to userspaceAnton Blanchard2013-11-211-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | When reading from the dispatch trace log (dtl) userspace interface, I sometimes see duplicate entries. One example: # hexdump -C dtl.out 00000000 07 04 00 0c 00 00 48 44 00 00 00 00 00 00 00 00 00000010 00 0c a0 b4 16 83 6d 68 00 00 00 00 00 00 00 00 00000020 00 00 00 00 10 00 13 50 80 00 00 00 00 00 d0 32 00000030 07 04 00 0c 00 00 48 44 00 00 00 00 00 00 00 00 00000040 00 0c a0 b4 16 83 6d 68 00 00 00 00 00 00 00 00 00000050 00 00 00 00 10 00 13 50 80 00 00 00 00 00 d0 32 The problem is in scan_dispatch_log() where we call dtl_consumer() but bail out before incrementing the index. To fix this I moved dtl_consumer() after the timebase comparison. Signed-off-by: Anton Blanchard <anton@samba.org> Cc: stable@vger.kernel.org Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* Merge branch 'next' of ↵Linus Torvalds2013-09-061-9/+9
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc Pull powerpc updates from Ben Herrenschmidt: "Here's the powerpc batch for this merge window. Some of the highlights are: - A bunch of endian fixes ! We don't have full LE support yet in that release but this contains a lot of fixes all over arch/powerpc to use the proper accessors, call the firmware with the right endian mode, etc... - A few updates to our "powernv" platform (non-virtualized, the one to run KVM on), among other, support for bridging the P8 LPC bus for UARTs, support and some EEH fixes. - Some mpc51xx clock API cleanups in preparation for a clock API overhaul - A pile of cleanups of our old math emulation code, including better support for using it to emulate optional FP instructions on embedded chips that otherwise have a HW FPU. - Some infrastructure in selftest, for powerpc now, but could be generalized, initially used by some tests for our perf instruction counting code. - A pile of fixes for hotplug on pseries (that was seriously bitrotting) - The usual slew of freescale embedded updates, new boards, 64-bit hiberation support, e6500 core PMU support, etc..." * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (146 commits) powerpc: Correct FSCR bit definitions powerpc/xmon: Fix printing of set of CPUs in xmon powerpc/pseries: Move lparcfg.c to platforms/pseries powerpc/powernv: Return secondary CPUs to firmware on kexec powerpc/btext: Fix CONFIG_PPC_EARLY_DEBUG_BOOTX on ppc32 powerpc: Cleanup handling of the DSCR bit in the FSCR register powerpc/pseries: Child nodes are not detached by dlpar_detach_node powerpc/pseries: Add mising of_node_put in delete_dt_node powerpc/pseries: Make dlpar_configure_connector parent node aware powerpc/pseries: Do all node initialization in dlpar_parse_cc_node powerpc/pseries: Fix parsing of initial node path in update_dt_node powerpc/pseries: Pack update_props_workarea to map correctly to rtas buffer header powerpc/pseries: Fix over writing of rtas return code in update_dt_node powerpc/pseries: Fix creation of loop in device node property list powerpc: Skip emulating & leave interrupts off for kernel program checks powerpc: Add more exception trampolines for hypervisor exceptions powerpc: Fix location and rename exception trampolines powerpc: Add more trap names to xmon powerpc/pseries: Add a warning in the case of cross-cpu VPA registration powerpc: Update the 00-Index in Documentation/powerpc ...
| * powerpc: Fix little endian lppaca, slb_shadow and dtl_entryAnton Blanchard2013-08-141-8/+8
| | | | | | | | | | | | | | | | | | | | | | The lppaca, slb_shadow and dtl_entry hypervisor structures are big endian, so we have to byte swap them in little endian builds. LE KVM hosts will also need to be fixed but for now add an #error to remind us. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
| * powerpc: Add some endian annotations to time and xics codeAnton Blanchard2013-08-141-1/+1
| | | | | | | | | | | | | | Fix a couple of sparse warnings. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* | PTR_RET is now PTR_ERR_OR_ZERO(): Replace most.Rusty Russell2013-07-151-1/+1
|/ | | | | | | | | | | | Sweep of the simple cases. Cc: netdev@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-arm-kernel@lists.infradead.org Cc: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: Delete __cpuinit usage from all usersPaul Gortmaker2013-07-011-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. This removes all the powerpc uses of the __cpuinit macros. There are no __CPUINIT users in assembly files in powerpc. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Josh Boyer <jwboyer@gmail.com> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: Kumar Gala <galak@kernel.crashing.org> Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: Use PTR_RET instead of IS_ERR/PTR_ERRAdrian-Leonard Radu2013-04-181-3/+1
| | | | | | Signed-off-by: Adrian-Leonard Radu <ady8radu@gmail.com> Acked-by: Geoff Levand <geoff@infradead.org> Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
* Merge branch 'timers-core-for-linus' of ↵Linus Torvalds2013-02-191-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer changes from Ingo Molnar: "Main changes: - ntp: Add CONFIG_RTC_SYSTOHC: a generic RTC driver facility complementing the existing CONFIG_RTC_HCTOSYS, which uses NTP to keep the hardware clock updated. - posix-timers: Fix clock_adjtime to always return timex data on success. This is changing the ABI, but no breakage was expected and found - caution is warranted nevertheless. - platform persistent clock improvements/cleanups. - clockevents: refactor timer broadcast handling to be more generic and less duplicated with matching architecture code (mostly ARM motivated.) - various fixes and cleanups" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timers/x86/hpet: Use HPET_COUNTER to specify the hpet counter in vread_hpet() posix-cpu-timers: Fix nanosleep task_struct leak clockevents: Fix generic broadcast for FEAT_C3STOP time, Fix setting of hardware clock in NTP code hrtimer: Prevent hrtimer_enqueue_reprogram race clockevents: Add generic timer broadcast function clockevents: Add generic timer broadcast receiver timekeeping: Switch HAS_PERSISTENT_CLOCK to ALWAYS_USE_PERSISTENT_CLOCK x86/time/rtc: Don't print extended CMOS year when reading RTC x86: Select HAS_PERSISTENT_CLOCK on x86 timekeeping: Add CONFIG_HAS_PERSISTENT_CLOCK option rtc: Skip the suspend/resume handling if persistent clock exist timekeeping: Add persistent_clock_exist flag posix-timers: Fix clock_adjtime to always return timex data on success Round the calculated scale factor in set_cyc2ns_scale() NTP: Add a CONFIG_RTC_SYSTOHC configuration MAINTAINERS: Update John Stultz's email time: create __getnstimeofday for WARNless calls
| * Merge branch 'fortglx/3.9/time' of git://git.linaro.org/people/jstultz/linux ↵Thomas Gleixner2013-02-041-1/+1
| |\ | | | | | | | | | | | | | | | | | | | | | into timers/core Trivial conflict in arch/x86/Kconfig Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * NTP: Add a CONFIG_RTC_SYSTOHC configurationJason Gunthorpe2013-01-151-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The purpose of this option is to allow ARM/etc systems that rely on the class RTC subsystem to have the same kind of automatic NTP based synchronization that we have on PC platforms. Today ARM does not implement update_persistent_clock and makes extensive use of the class RTC system. When enabled CONFIG_RTC_SYSTOHC will provide a generic rtc_update_persistent_clock that stores the current time in the RTC and is intended complement the existing CONFIG_RTC_HCTOSYS option that loads the RTC at boot. Like with RTC_HCTOSYS the platform's update_persistent_clock is used first, if it works. Platforms with mixed class RTC and non-RTC drivers need to return ENODEV when class RTC should be used. Such an update for PPC is included in this patch. Long term, implementations of update_persistent_clock should migrate to proper class RTC drivers and use CONFIG_RTC_SYSTOHC instead. Tested on ARM kirkwood and PPC405 Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
* | | Merge branch 'sched-core-for-linus' of ↵Linus Torvalds2013-02-191-2/+3
|\ \ \ | |/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler changes from Ingo Molnar: "Main changes: - scheduler side full-dynticks (user-space execution is undisturbed and receives no timer IRQs) preparation changes that convert the cputime accounting code to be full-dynticks ready, from Frederic Weisbecker. - Initial sched.h split-up changes, by Clark Williams - select_idle_sibling() performance improvement by Mike Galbraith: " 1 tbench pair (worst case) in a 10 core + SMT package: pre 15.22 MB/sec 1 procs post 252.01 MB/sec 1 procs " - sched_rr_get_interval() ABI fix/change. We think this detail is not used by apps (so it's not an ABI in practice), but lets keep it under observation. - misc RT scheduling cleanups, optimizations" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) sched/rt: Add <linux/sched/rt.h> header to <linux/init_task.h> cputime: Remove irqsave from seqlock readers sched, powerpc: Fix sched.h split-up build failure cputime: Restore CPU_ACCOUNTING config defaults for PPC64 sched/rt: Move rt specific bits into new header file sched/rt: Add a tuning knob to allow changing SCHED_RR timeslice sched: Move sched.h sysctl bits into separate header sched: Fix signedness bug in yield_to() sched: Fix select_idle_sibling() bouncing cow syndrome sched/rt: Further simplify pick_rt_task() sched/rt: Do not account zero delta_exec in update_curr_rt() cputime: Safely read cputime of full dynticks CPUs kvm: Prepare to add generic guest entry/exit callbacks cputime: Use accessors to read task cputime stats cputime: Allow dynamic switch between tick/virtual based cputime accounting cputime: Generic on-demand virtual cputime accounting cputime: Move default nsecs_to_cputime() to jiffies based cputime file cputime: Librarize per nsecs resolution cputime definitions cputime: Avoid multiplication overflow on utime scaling context_tracking: Export context state for generic vtime ... Fix up conflict in kernel/context_tracking.c due to comment additions.
| * | kvm: Prepare to add generic guest entry/exit callbacksFrederic Weisbecker2013-01-271-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Do some ground preparatory work before adding guest_enter() and guest_exit() context tracking callbacks. Those will be later used to read the guest cputime safely when we run in full dynticks mode. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Gleb Natapov <gleb@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de>
| * | cputime: Generic on-demand virtual cputime accountingFrederic Weisbecker2013-01-271-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we want to stop the tick further idle, we need to be able to account the cputime without using the tick. Virtual based cputime accounting solves that problem by hooking into kernel/user boundaries. However implementing CONFIG_VIRT_CPU_ACCOUNTING require low level hooks and involves more overhead. But we already have a generic context tracking subsystem that is required for RCU needs by archs which plan to shut down the tick outside idle. This patch implements a generic virtual based cputime accounting that relies on these generic kernel/user hooks. There are some upsides of doing this: - This requires no arch code to implement CONFIG_VIRT_CPU_ACCOUNTING if context tracking is already built (already necessary for RCU in full tickless mode). - We can rely on the generic context tracking subsystem to dynamically (de)activate the hooks, so that we can switch anytime between virtual and tick based accounting. This way we don't have the overhead of the virtual accounting when the tick is running periodically. And one downside: - There is probably more overhead than a native virtual based cputime accounting. But this relies on hooks that are already set anyway. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Namhyung Kim <namhyung.kim@lge.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de>
* | | powerpc: Max next_tb to prevent from replaying timer interruptTiejun Chen2013-01-291-2/+7
|/ / | | | | | | | | | | | | | | | | | | | | With lazy interrupt, we always call __check_irq_replaysome with decrementers_next_tb to check if we need to replay timer interrupt. So in hotplug case we also need to set decrementers_next_tb as MAX to make sure __check_irq_replay don't replay timer interrupt when return as we expect, otherwise we'll trap here infinitely. Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* | powerpc/vdso: Remove redundant locking in update_vsyscall_tz()Shan Hai2013-01-031-5/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The locking in update_vsyscall_tz() is not only unnecessary because the vdso code copies the data unproteced in __kernel_gettimeofday() but also introduces a hard to reproduce race condition between update_vsyscall() and update_vsyscall_tz(), which causes user space process to loop forever in vdso code. The following patch removes the locking from update_vsyscall_tz(). Locking is not only unnecessary because the vdso code copies the data unprotected in __kernel_gettimeofday() but also erroneous because updating the tb_update_count is not atomic and introduces a hard to reproduce race condition between update_vsyscall() and update_vsyscall_tz(), which further causes user space process to loop forever in vdso code. The below scenario describes the race condition, x==0 Boot CPU other CPU proc_P: x==0 timer interrupt update_vsyscall x==1 x++;sync settimeofday update_vsyscall_tz x==2 x++;sync x==3 sync;x++ sync;x++ proc_P: x==3 (loops until x becomes even) Because the ++ operator would be implemented as three instructions and not atomic on powerpc. A similar change was made for x86 in commit 6c260d58634 ("x86: vdso: Remove bogus locking in update_vsyscall_tz") Signed-off-by: Shan Hai <shan.hai@windriver.com> CC: <stable@vger.kernel.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* | vtime: Warn if irqs aren't disabled on system time accounting APIsFrederic Weisbecker2012-11-201-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | System time accounting APIs such as vtime_account_system() and vtime_account_idle() need to be irqsafe. Current callers include irq entry, exit and kvm, all of which have been checked against that requirement. Now it's better to grow that with an automatic check in case we have further callers or we missed something. Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
* | vtime: Consolidate a bit the ctx switch codeFrederic Weisbecker2012-11-191-6/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On ia64 and powerpc, vtime context switch only consists in flushing system and user pending time, plus a few arch housekeeping. Consolidate that into a generic implementation. s390 is a special case because pending user and system time accounting there is hard to dissociate. So it's keeping its own implementation. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
* | vtime: Explicitly account pending user time on process tickFrederic Weisbecker2012-11-191-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All vtime implementations just flush the user time on process tick. Consolidate that in generic code by calling a user time accounting helper. This avoids an indirect call in ia64 and prepare to also consolidate vtime context switch code. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
* | vtime: Remove the underscore prefix invasionFrederic Weisbecker2012-11-191-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Prepending irq-unsafe vtime APIs with underscores was actually a bad idea as the result is a big mess in the API namespace that is even waiting to be further extended. Also these helpers are always called from irq safe callers except kvm. Just provide a vtime_account_system_irqsafe() for this specific case so that we can remove the underscore prefix on other vtime functions. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
* | vtime: Make vtime_account_system() irqsafeFrederic Weisbecker2012-10-291-2/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | vtime_account_system() currently has only one caller with vtime_account() which is irq safe. Now we are going to call it from other places like kvm where irqs are not always disabled by the time we account the cputime. So let's make it irqsafe. The arch implementation part is now prefixed with "__". vtime_account_idle() arch implementation is prefixed accordingly to stay consistent. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
* Merge branch 'timers-core-for-linus' of ↵Linus Torvalds2012-10-121-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer core update from Thomas Gleixner: - Bug fixes (one for a longstanding dead loop issue) - Rework of time related vsyscalls - Alarm timer updates - Jiffies updates to remove compile time dependencies * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timekeeping: Cast raw_interval to u64 to avoid shift overflow timers: Fix endless looping between cascade() and internal_add_timer() time/jiffies: bring back unconditional LATCH definition time: Convert x86_64 to using new update_vsyscall time: Only do nanosecond rounding on GENERIC_TIME_VSYSCALL_OLD systems time: Introduce new GENERIC_TIME_VSYSCALL time: Convert CONFIG_GENERIC_TIME_VSYSCALL to CONFIG_GENERIC_TIME_VSYSCALL_OLD time: Move update_vsyscall definitions to timekeeper_internal.h time: Move timekeeper structure to timekeeper_internal.h for vsyscall changes jiffies: Remove compile time assumptions about CLOCK_TICK_RATE jiffies: Kill unused TICK_USEC_TO_NSEC alarmtimer: Rename alarmtimer_remove to alarmtimer_dequeue alarmtimer: Remove unused helpers & defines alarmtimer: Use hrtimer per-alarm instead of per-base alarmtimer: Implement minimum alarm interval for allowing suspend
| * time: Convert CONFIG_GENERIC_TIME_VSYSCALL to CONFIG_GENERIC_TIME_VSYSCALL_OLDJohn Stultz2012-09-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To help migrate archtectures over to the new update_vsyscall method, redfine CONFIG_GENERIC_TIME_VSYSCALL as CONFIG_GENERIC_TIME_VSYSCALL_OLD Cc: Tony Luck <tony.luck@intel.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Turner <pjt@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
| * time: Move update_vsyscall definitions to timekeeper_internal.hJohn Stultz2012-09-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since users will need to include timekeeper_internal.h, move update_vsyscall definitions to timekeeper_internal.h. Cc: Tony Luck <tony.luck@intel.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Paul Turner <pjt@google.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
* | Merge branch 'next' of ↵Linus Torvalds2012-10-061-4/+4
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc Pull powerpc updates from Benjamin Herrenschmidt: "Some highlights in addition to the usual batch of fixes: - 64TB address space support for 64-bit processes by Aneesh Kumar - Gavin Shan did a major cleanup & re-organization of our EEH support code (IBM fancy PCI error handling & recovery infrastructure) which paves the way for supporting different platform backends, along with some rework of the PCIe code for the PowerNV platform in order to remove home made resource allocations and instead use the generic code (which is possible after some small improvements to it done by Gavin). - Uprobes support by Ananth N Mavinakayanahalli - A pile of embedded updates from Freescale folks, including new SoC and board supports, more KVM stuff including preparing for 64-bit BookE KVM support, ePAPR 1.1 updates, etc..." Fixup trivial conflicts in drivers/scsi/ipr.c * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (146 commits) powerpc/iommu: Fix multiple issues with IOMMU pools code powerpc: Fix VMX fix for memcpy case driver/mtd:IFC NAND:Initialise internal SRAM before any write powerpc/fsl-pci: use 'Header Type' to identify PCIE mode powerpc/eeh: Don't release eeh_mutex in eeh_phb_pe_get powerpc: Remove tlb batching hack for nighthawk powerpc: Set paca->data_offset = 0 for boot cpu powerpc/perf: Sample only if SIAR-Valid bit is set in P7+ powerpc/fsl-pci: fix warning when CONFIG_SWIOTLB is disabled powerpc/mpc85xx: Update interrupt handling for IFC controller powerpc/85xx: Enable USB support in p1023rds_defconfig powerpc/smp: Do not disable IPI interrupts during suspend powerpc/eeh: Fix crash on converting OF node to edev powerpc/eeh: Lock module while handling EEH event powerpc/kprobe: Don't emulate store when kprobe stwu r1 powerpc/kprobe: Complete kprobe and migrate exception frame powerpc/kprobe: Introduce a new thread flag powerpc: Remove unused __get_user64() and __put_user64() powerpc/eeh: Global mutex to protect PE tree powerpc/eeh: Remove EEH PE for normal PCI hotplug ...
| * | powerpc/trace: Fix interrupt tracepoints vs. RCULi Zhong2012-09-171-4/+4
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are a few tracepoints in the interrupt code path, which is before irq_enter(), or after irq_exit(), like trace_irq_entry()/trace_irq_exit() in do_IRQ(), trace_timer_interrupt_entry()/trace_timer_interrupt_exit() in timer_interrupt(). If the interrupt is from idle(), and because tracepoint contains RCU read-side critical section, we could see following suspicious RCU usage reported: [ 145.127743] =============================== [ 145.127747] [ INFO: suspicious RCU usage. ] [ 145.127752] 3.6.0-rc3+ #1 Not tainted [ 145.127755] ------------------------------- [ 145.127759] /root/.workdir/linux/arch/powerpc/include/asm/trace.h:33 suspicious rcu_dereference_check() usage! [ 145.127765] [ 145.127765] other info that might help us debug this: [ 145.127765] [ 145.127771] [ 145.127771] RCU used illegally from idle CPU! [ 145.127771] rcu_scheduler_active = 1, debug_locks = 0 [ 145.127777] RCU used illegally from extended quiescent state! [ 145.127781] no locks held by swapper/0/0. [ 145.127785] [ 145.127785] stack backtrace: [ 145.127789] Call Trace: [ 145.127796] [c00000000108b530] [c000000000013c40] .show_stack +0x70/0x1c0 (unreliable) [ 145.127806] [c00000000108b5e0] [c0000000000f59d8] .lockdep_rcu_suspicious+0x118/0x150 [ 145.127813] [c00000000108b680] [c00000000000fc58] .do_IRQ+0x498/0x500 [ 145.127820] [c00000000108b750] [c000000000003950] hardware_interrupt_common+0x150/0x180 [ 145.127828] --- Exception: 501 at .plpar_hcall_norets+0x84/0xd4 [ 145.127828] LR = .check_and_cede_processor+0x38/0x70 [ 145.127836] [c00000000108bab0] [c0000000000665dc] .shared_cede_loop +0x5c/0x100 [ 145.127844] [c00000000108bb70] [c000000000588ab0] .cpuidle_enter +0x30/0x50 [ 145.127850] [c00000000108bbe0] [c000000000588b0c] .cpuidle_enter_state+0x3c/0xb0 [ 145.127857] [c00000000108bc60] [c000000000589730] .cpuidle_idle_call +0x150/0x6c0 [ 145.127863] [c00000000108bd30] [c000000000058440] .pSeries_idle +0x10/0x40 [ 145.127870] [c00000000108bda0] [c00000000001683c] .cpu_idle +0x18c/0x2d0 [ 145.127876] [c00000000108be60] [c00000000000b434] .rest_init +0x124/0x1b0 [ 145.127884] [c00000000108bef0] [c0000000009d0d28] .start_kernel +0x568/0x588 [ 145.127890] [c00000000108bf90] [c000000000009660] .start_here_common +0x20/0x40 This is because the RCU usage in interrupt context should be used in area marked by rcu_irq_enter()/rcu_irq_exit(), called in irq_enter()/irq_exit() respectively. Move them into the irq_enter()/irq_exit() area to avoid the reporting. Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* | Merge branch 'sched-core-for-linus' of ↵Linus Torvalds2012-10-011-20/+35
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler changes from Ingo Molnar: "Continued quest to clean up and enhance the cputime code by Frederic Weisbecker, in preparation for future tickless kernel features. Other than that, smallish changes." Fix up trivial conflicts due to additions next to each other in arch/{x86/}Kconfig * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits) cputime: Make finegrained irqtime accounting generally available cputime: Gather time/stats accounting config options into a single menu ia64: Reuse system and user vtime accounting functions on task switch ia64: Consolidate user vtime accounting vtime: Consolidate system/idle context detection cputime: Use a proper subsystem naming for vtime related APIs sched: cpu_power: enable ARCH_POWER sched/nohz: Clean up select_nohz_load_balancer() sched: Fix load avg vs. cpu-hotplug sched: Remove __ARCH_WANT_INTERRUPTS_ON_CTXSW sched: Fix nohz_idle_balance() sched: Remove useless code in yield_to() sched: Add time unit suffix to sched sysctl knobs sched/debug: Limit sd->*_idx range on sysctl sched: Remove AFFINE_WAKEUPS feature flag s390: Remove leftover account_tick_vtime() header cputime: Consolidate vtime handling on context switch sched: Move cputime code to its own file cputime: Generalize CONFIG_VIRT_CPU_ACCOUNTING tile: Remove SD_PREFER_LOCAL leftover ...
| * vtime: Consolidate system/idle context detectionFrederic Weisbecker2012-09-251-19/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move the code that finds out to which context we account the cputime into generic layer. Archs that consider the whole time spent in the idle task as idle time (ia64, powerpc) can rely on the generic vtime_account() and implement vtime_account_system() and vtime_account_idle(), letting the generic code to decide when to call which API. Archs that have their own meaning of idle time, such as s390 that only considers the time spent in CPU low power mode as idle time, can just override vtime_account(). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org>
| * cputime: Use a proper subsystem naming for vtime related APIsFrederic Weisbecker2012-09-251-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use a naming based on vtime as a prefix for virtual based cputime accounting APIs: - account_system_vtime() -> vtime_account() - account_switch_vtime() -> vtime_task_switch() It makes it easier to allow for further declension such as vtime_account_system(), vtime_account_idle(), ... if we want to find out the context we account to from generic code. This also make it better to know on which subsystem these APIs refer to. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org>
| * cputime: Consolidate vtime handling on context switchFrederic Weisbecker2012-08-201-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The archs that implement virtual cputime accounting all flush the cputime of a task when it gets descheduled and sometimes set up some ground initialization for the next task to account its cputime. These archs all put their own hooks in their context switch callbacks and handle the off-case themselves. Consolidate this by creating a new account_switch_vtime() callback called in generic code right after a context switch and that these archs must implement to flush the prev task cputime and initialize the next task cputime related state. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org>
* | powerpc: Give hypervisor decrementer interrupts their own handlerPaul Mackerras2012-09-051-0/+9
|/ | | | | | | | | | | | | | | | | | | At the moment the handler for hypervisor decrementer interrupts is the same as for decrementer interrupts, i.e. timer_interrupt(). This is bogus; if we ever do get a hypervisor decrementer interrupt it won't have anything to do with the next timer event. In fact the only time we get hypervisor decrementer interrupts is when one is left pending on exit from a KVM guest. When we get a hypervisor decrementer interrupt we don't need to do anything special to clear it, since they are edge-triggered on the transition of HDEC from 0 to -1. Thus this adds an empty handler function for them. We don't need to have them masked when interrupts are soft-disabled, so we use STD_EXCEPTION_HV instead of MASKABLE_EXCEPTION_HV. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc/time: Sanity check of decrementer expiration is necessaryPaul Mackerras2012-06-081-3/+11
| | | | | | | | | | | | | | | | | | | | | This reverts 68568add2c ("powerpc/time: Remove unnecessary sanity check of decrementer expiration"). We do need to check whether we have reached the expiration time of the next event, because we sometimes get an early decrementer interrupt, most notably when we set the decrementer to 1 in arch_irq_work_raise(). The effect of not having the sanity check is that if timer_interrupt() gets called early, we leave the decrementer set to its maximum value, which means we then don't get any more decrementer interrupts for about 4 seconds (or longer, depending on timebase frequency). I saw these pauses as a consequence of getting a stray hypervisor decrementer interrupt left over from exiting a KVM guest. This isn't quite a straight revert because of changes to the surrounding code, but it restores the same algorithm as was previously used. Cc: stable@vger.kernel.org Acked-by: Anton Blanchard <anton@samba.org> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
* KVM: PPC: Use clockevent multiplier and shifter for decrementerBharat Bhushan2012-05-061-1/+2
| | | | | | | | | | | | | | | | | Time for which the hrtimer is started for decrementer emulation is calculated using tb_ticks_per_usec. While hrtimer uses the clockevent for DEC reprogramming (if needed) and which calculate timebase ticks using the multiplier and shifter mechanism implemented within clockevent layer. It was observed that this conversion (timebase->time->timebase) are not correct because the mechanism are not consistent. In our setup it adds 2% jitter. With this patch clockevent multiplier and shifter mechanism are used when starting hrtimer for decrementer emulation. Now the jitter is < 0.5%. Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
* powerpc: Remove FW_FEATURE ISERIES from arch codeStephen Rothwell2012-03-211-105/+3
| | | | | | | This is no longer selectable, so just remove all the dependent code. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: Rework lazy-interrupt handlingBenjamin Herrenschmidt2012-03-091-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current implementation of lazy interrupts handling has some issues that this tries to address. We don't do the various workarounds we need to do when re-enabling interrupts in some cases such as when returning from an interrupt and thus we may still lose or get delayed decrementer or doorbell interrupts. The current scheme also makes it much harder to handle the external "edge" interrupts provided by some BookE processors when using the EPR facility (External Proxy) and the Freescale Hypervisor. Additionally, we tend to keep interrupts hard disabled in a number of cases, such as decrementer interrupts, external interrupts, or when a masked decrementer interrupt is pending. This is sub-optimal. This is an attempt at fixing it all in one go by reworking the way we do the lazy interrupt disabling from the ground up. The base idea is to replace the "hard_enabled" field with a "irq_happened" field in which we store a bit mask of what interrupt occurred while soft-disabled. When re-enabling, either via arch_local_irq_restore() or when returning from an interrupt, we can now decide what to do by testing bits in that field. We then implement replaying of the missed interrupts either by re-using the existing exception frame (in exception exit case) or via the creation of a new one from an assembly trampoline (in the arch_local_irq_enable case). This removes the need to play with the decrementer to try to create fake interrupts, among others. In addition, this adds a few refinements: - We no longer hard disable decrementer interrupts that occur while soft-disabled. We now simply bump the decrementer back to max (on BookS) or leave it stopped (on BookE) and continue with hard interrupts enabled, which means that we'll potentially get better sample quality from performance monitor interrupts. - Timer, decrementer and doorbell interrupts now hard-enable shortly after removing the source of the interrupt, which means they no longer run entirely hard disabled. Again, this will improve perf sample quality. - On Book3E 64-bit, we now make the performance monitor interrupt act as an NMI like Book3S (the necessary C code for that to work appear to already be present in the FSL perf code, notably calling nmi_enter instead of irq_enter). (This also fixes a bug where BookE perfmon interrupts could clobber r14 ... oops) - We could make "masked" decrementer interrupts act as NMIs when doing timer-based perf sampling to improve the sample quality. Signed-off-by-yet: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- v2: - Add hard-enable to decrementer, timer and doorbells - Fix CR clobber in masked irq handling on BookE - Make embedded perf interrupt act as an NMI - Add a PACA_HAPPENED_EE_EDGE for use by FSL if they want to retrigger an interrupt without preventing hard-enable v3: - Fix or vs. ori bug on Book3E - Fix enabling of interrupts for some exceptions on Book3E v4: - Fix resend of doorbells on return from interrupt on Book3E v5: - Rebased on top of my latest series, which involves some significant rework of some aspects of the patch. v6: - 32-bit compile fix - more compile fixes with various .config combos - factor out the asm code to soft-disable interrupts - remove the C wrapper around preempt_schedule_irq v7: - Fix a bug with hard irq state tracking on native power7
* powerpc: Fix wrong divisor in usecs_to_cputimeAndreas Schwab2011-12-191-5/+5
| | | | | | | | | | | | | | | Commit d57af9b (taskstats: use real microsecond granularity for CPU times) renamed msecs_to_cputime to usecs_to_cputime, but failed to update all numbers on the way. This causes nonsensical cpu idle/iowait values to be displayed in /proc/stat (the only user of usecs_to_cputime so far). This also renames __cputime_msec_factor to __cputime_usec_factor, adapting its value and using it directly in cputime_to_usecs instead of doing two multiplications. Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Acked-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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