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* Introduce a new, HVM compatible, paravirtualized timer driver for Xen.gibbs2013-08-291-352/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use this new driver for both PV and HVM instances. This driver requires a Xen hypervisor that supports vector callbacks, VCPUOP hypercalls, and reports that it has a "safe PV clock". New timer driver: Submitted by: will Sponsored by: Spectra Logic Corporation PV port to new driver, and bug fixes: Submitted by: Roger Pau Monné Sponsored by: Citrix Systems R&D sys/dev/xen/timer/timer.c: - Register a PV timer device driver which (currently) implements device_{identify,probe,attach} and stubs device_detach. The detach routine requires functionality not provided by timecounters(4). The suspend and resume routines need additional work (due to Xen requiring that the hypercalls be executed on the target VCPU), and aren't needed for our purposes. - Make sure there can only be one device instance of this driver, and that it only registers one eventtimers(4) and one timecounters(4) device interface. Make both interfaces use PCPU data as needed. - Match, with a few style cleanups & API differences, the Xen versions of the "fetch time" functions. - Document the magic scale_delta() better for the i386 version. - When registering the event timer, bind a separate event channel for the timer VIRQ to the device's event timer interrupt handler for each active VCPU. Describe each interrupt as "xen_et:c%d", so they can be identified per CPU in "vmstat -i" or "show intrcnt" in KDB. - When scheduling a timer into the hypervisor, try up to 60 times if the hypervisor rejects the time as being in the past. In the common case, this retry shouldn't happen, and if it does, it should only happen once. This is because the event timer advertises a minimum period of 100usec, which is only less than the usual hypercall round trip time about 1 out of every 100 tries. (Unlike other similar drivers, this one actually checks whether the hypervisor accepted the singleshot timer set hypercall.) - Implement a RTC PV clock based on the hypervisor wallclock. sys/conf/files: - Add dev/xen/timer/timer.c if the kernel configuration includes either the XEN or XENHVM options. sys/conf/files.i386: sys/i386/include/xen/xen_clock_util.h: sys/i386/xen/clock.c: sys/i386/xen/xen_clock_util.c: sys/i386/xen/mp_machdep.c: sys/i386/xen/xen_rtc.c: - Remove previous PV timer used in i386 XEN PV kernels, the new timer introduced in this change is used instead (so we share the same code between PVHVM and PV). MFC after: 2 weeks
* Implement vector callback for PVHVM and unify event channel implementationsgibbs2013-08-291-23/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Re-structure Xen HVM support so that: - Xen is detected and hypercalls can be performed very early in system startup. - Xen interrupt services are implemented using FreeBSD's native interrupt delivery infrastructure. - the Xen interrupt service implementation is shared between PV and HVM guests. - Xen interrupt handlers can optionally use a filter handler in order to avoid the overhead of dispatch to an interrupt thread. - interrupt load can be distributed among all available CPUs. - the overhead of accessing the emulated local and I/O apics on HVM is removed for event channel port events. - a similar optimization can eventually, and fairly easily, be used to optimize MSI. Early Xen detection, HVM refactoring, PVHVM interrupt infrastructure, and misc Xen cleanups: Sponsored by: Spectra Logic Corporation Unification of PV & HVM interrupt infrastructure, bug fixes, and misc Xen cleanups: Submitted by: Roger Pau Monné Sponsored by: Citrix Systems R&D sys/x86/x86/local_apic.c: sys/amd64/include/apicvar.h: sys/i386/include/apicvar.h: sys/amd64/amd64/apic_vector.S: sys/i386/i386/apic_vector.s: sys/amd64/amd64/machdep.c: sys/i386/i386/machdep.c: sys/i386/xen/exception.s: sys/x86/include/segments.h: Reserve IDT vector 0x93 for the Xen event channel upcall interrupt handler. On Hypervisors that support the direct vector callback feature, we can request that this vector be called directly by an injected HVM interrupt event, instead of a simulated PCI interrupt on the Xen platform PCI device. This avoids all of the overhead of dealing with the emulated I/O APIC and local APIC. It also means that the Hypervisor can inject these events on any CPU, allowing upcalls for different ports to be handled in parallel. sys/amd64/amd64/mp_machdep.c: sys/i386/i386/mp_machdep.c: Map Xen per-vcpu area during AP startup. sys/amd64/include/intr_machdep.h: sys/i386/include/intr_machdep.h: Increase the FreeBSD IRQ vector table to include space for event channel interrupt sources. sys/amd64/include/pcpu.h: sys/i386/include/pcpu.h: Remove Xen HVM per-cpu variable data. These fields are now allocated via the dynamic per-cpu scheme. See xen_intr.c for details. sys/amd64/include/xen/hypercall.h: sys/dev/xen/blkback/blkback.c: sys/i386/include/xen/xenvar.h: sys/i386/xen/clock.c: sys/i386/xen/xen_machdep.c: sys/xen/gnttab.c: Prefer FreeBSD primatives to Linux ones in Xen support code. sys/amd64/include/xen/xen-os.h: sys/i386/include/xen/xen-os.h: sys/xen/xen-os.h: sys/dev/xen/balloon/balloon.c: sys/dev/xen/blkback/blkback.c: sys/dev/xen/blkfront/blkfront.c: sys/dev/xen/console/xencons_ring.c: sys/dev/xen/control/control.c: sys/dev/xen/netback/netback.c: sys/dev/xen/netfront/netfront.c: sys/dev/xen/xenpci/xenpci.c: sys/i386/i386/machdep.c: sys/i386/include/pmap.h: sys/i386/include/xen/xenfunc.h: sys/i386/isa/npx.c: sys/i386/xen/clock.c: sys/i386/xen/mp_machdep.c: sys/i386/xen/mptable.c: sys/i386/xen/xen_clock_util.c: sys/i386/xen/xen_machdep.c: sys/i386/xen/xen_rtc.c: sys/xen/evtchn/evtchn_dev.c: sys/xen/features.c: sys/xen/gnttab.c: sys/xen/gnttab.h: sys/xen/hvm.h: sys/xen/xenbus/xenbus.c: sys/xen/xenbus/xenbus_if.m: sys/xen/xenbus/xenbusb_front.c: sys/xen/xenbus/xenbusvar.h: sys/xen/xenstore/xenstore.c: sys/xen/xenstore/xenstore_dev.c: sys/xen/xenstore/xenstorevar.h: Pull common Xen OS support functions/settings into xen/xen-os.h. sys/amd64/include/xen/xen-os.h: sys/i386/include/xen/xen-os.h: sys/xen/xen-os.h: Remove constants, macros, and functions unused in FreeBSD's Xen support. sys/xen/xen-os.h: sys/i386/xen/xen_machdep.c: sys/x86/xen/hvm.c: Introduce new functions xen_domain(), xen_pv_domain(), and xen_hvm_domain(). These are used in favor of #ifdefs so that FreeBSD can dynamically detect and adapt to the presence of a hypervisor. The goal is to have an HVM optimized GENERIC, but more is necessary before this is possible. sys/amd64/amd64/machdep.c: sys/dev/xen/xenpci/xenpcivar.h: sys/dev/xen/xenpci/xenpci.c: sys/x86/xen/hvm.c: sys/sys/kernel.h: Refactor magic ioport, Hypercall table and Hypervisor shared information page setup, and move it to a dedicated HVM support module. HVM mode initialization is now triggered during the SI_SUB_HYPERVISOR phase of system startup. This currently occurs just after the kernel VM is fully setup which is just enough infrastructure to allow the hypercall table and shared info page to be properly mapped. sys/xen/hvm.h: sys/x86/xen/hvm.c: Add definitions and a method for configuring Hypervisor event delievery via a direct vector callback. sys/amd64/include/xen/xen-os.h: sys/x86/xen/hvm.c: sys/conf/files: sys/conf/files.amd64: sys/conf/files.i386: Adjust kernel build to reflect the refactoring of early Xen startup code and Xen interrupt services. sys/dev/xen/blkback/blkback.c: sys/dev/xen/blkfront/blkfront.c: sys/dev/xen/blkfront/block.h: sys/dev/xen/control/control.c: sys/dev/xen/evtchn/evtchn_dev.c: sys/dev/xen/netback/netback.c: sys/dev/xen/netfront/netfront.c: sys/xen/xenstore/xenstore.c: sys/xen/evtchn/evtchn_dev.c: sys/dev/xen/console/console.c: sys/dev/xen/console/xencons_ring.c Adjust drivers to use new xen_intr_*() API. sys/dev/xen/blkback/blkback.c: Since blkback defers all event handling to a taskqueue, convert this task queue to a "fast" taskqueue, and schedule it via an interrupt filter. This avoids an unnecessary ithread context switch. sys/xen/xenstore/xenstore.c: The xenstore driver is MPSAFE. Indicate as much when registering its interrupt handler. sys/xen/xenbus/xenbus.c: sys/xen/xenbus/xenbusvar.h: Remove unused event channel APIs. sys/xen/evtchn.h: Remove all kernel Xen interrupt service API definitions from this file. It is now only used for structure and ioctl definitions related to the event channel userland device driver. Update the definitions in this file to match those from NetBSD. Implementing this interface will be necessary for Dom0 support. sys/xen/evtchn/evtchnvar.h: Add a header file for implemenation internal APIs related to managing event channels event delivery. This is used to allow, for example, the event channel userland device driver to access low-level routines that typical kernel consumers of event channel services should never access. sys/xen/interface/event_channel.h: sys/xen/xen_intr.h: Standardize on the evtchn_port_t type for referring to an event channel port id. In order to prevent low-level event channel APIs from leaking to kernel consumers who should not have access to this data, the type is defined twice: Once in the Xen provided event_channel.h, and again in xen/xen_intr.h. The double declaration is protected by __XEN_EVTCHN_PORT_DEFINED__ to ensure it is never declared twice within a given compilation unit. sys/xen/xen_intr.h: sys/xen/evtchn/evtchn.c: sys/x86/xen/xen_intr.c: sys/dev/xen/xenpci/evtchn.c: sys/dev/xen/xenpci/xenpcivar.h: New implementation of Xen interrupt services. This is similar in many respects to the i386 PV implementation with the exception that events for bound to event channel ports (i.e. not IPI, virtual IRQ, or physical IRQ) are further optimized to avoid mask/unmask operations that aren't necessary for these edge triggered events. Stubs exist for supporting physical IRQ binding, but will need additional work before this implementation can be fully shared between PV and HVM. sys/amd64/amd64/mp_machdep.c: sys/i386/i386/mp_machdep.c: sys/i386/xen/mp_machdep.c sys/x86/xen/hvm.c: Add support for placing vcpu_info into an arbritary memory page instead of using HYPERVISOR_shared_info->vcpu_info. This allows the creation of domains with more than 32 vcpus. sys/i386/i386/machdep.c: sys/i386/xen/clock.c: sys/i386/xen/xen_machdep.c: sys/i386/xen/exception.s: Add support for new event channle implementation.
* MFcalloutng:mav2013-02-281-17/+9
| | | | | | | Switch eventtimers(9) from using struct bintime to sbintime_t. Even before this not a single driver really supported full dynamic range of struct bintime even in theory, not speaking about practical inexpediency. This change legitimates the status quo and cleans up the code.
* Fix a minor warning in sys/i386/xen/clock.c.dim2012-11-121-1/+1
| | | | MFC after: 3 days
* Refactor Xen PV code to use new event timers subsystem. That uses one-shotmav2011-05-131-96/+101
| | | | | | | | | | | Xen timer and time counter to provide one-shot and periodic time events. On my tests this reduces idle interruts rate down to about 30Hz, and accor- ding to Xen VM Manager reduces host CPU load by three times comparing to the previous periodic 100Hz clock. Also now, when needed, it is possible to increase HZ rate without useless CPU burning during idle periods. Now only ia64 and some ARMs left not migrated to the new event timers.
* Remove bogus usage of INTR_FAST. "Fast" interrupts are now indicated byjhb2011-01-061-2/+2
| | | | | registering a filter handler rather than a threaded handler. Also remove a bogus use of INTR_MPSAFE for a filter.
* Reduce the Xen timecounter from 1GHz to 2^-9 GHz, thereby increasing thecperciva2010-12-111-2/+3
| | | | | | | | | | | | timecounter period from 2^32 ns (~4.3s) to 2^41 ns (~36m39s). Some time sharing systems can skip clock interrupts for a few seconds when under load (e.g., if we've recently used more than our fair share of CPU and someone else wants a burst of CPU) and we were losing time in quanta of 2^32 ns due to timecounter wrapping. Increasing the timecounter period up to 2^41 ns is definitely overkill, but we still have microsecond timecounter precision, and anyone using paravirtualized hardware when they need submicrosecond timing is crazy.
* Make the machdep.independent_wallclock sysctl do what it says on the box.cperciva2010-12-111-1/+2
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* In xen_get_timecount, return the full ns-precision time rather thancperciva2010-11-221-1/+1
| | | | | | | rounding to 1/HZ precision. I have no idea why the rounding was introduced in the first place, but it makes FreeBSD unhappy.
* Introduce the new kernel sub-tree x86 which should contain all the codeattilio2010-02-251-2/+2
| | | | | | | | | | | | | | shared and generalized between our current amd64, i386 and pc98. This is just an initial step that should lead to a more complete effort. For the moment, a very simple porting of cpufreq modules, BIOS calls and the whole MD specific ISA bus part is added to the sub-tree but ideally a lot of code might be added and more shared support should grow. Sponsored by: Sandvine Incorporated Reviewed by: emaste, kib, jhb, imp Discussed on: arch MFC: 3 weeks
* Fix the Xen TOD update when the hypervisor wall clock is nudged.adrian2009-05-291-0/+14
| | | | | | | | | | | | | | | | | | | | | The "wall clock" in the current code is actually the hypervisor start time. The time of day is the "start time" plus the hypervisor "uptime". Large enough bumps in the dom0 clock lead to a hypervisor "bump" which is implemented as a bump in the start time, not the uptime. The clock.c routines were reading in the hypervisor start time and then using this as the TOD. This meant that any hypervisor time bump would cause the FreeBSD DomU to set its TOD to the hypervisor start time, rather than the actual TOD. This fix is a bit hacky and some reshuffling should be done later on to clarify what is going on. I've left the wall clock code alone. (The code which updates shadow_tv and shadow_tv_version.) A new routine adds the uptime to the shadow_tv, which is then used to update the TOD. I've included some debugging so it is obvious when the clock is nudged. PR: 135008
* Rename statclock_disable variable to atrtcclock_disable that it actually is,mav2009-05-031-1/+0
| | | | | | | | | | | | | and hide it inside of atrtc driver. Add new tunable hint.atrtc.0.clock controlling it. Setting it to 0 disables using RTC clock as stat-/ profclock sources. Teach i386 and amd64 SMP platforms to emulate stat-/profclocks using i8254 hardclock, when LAPIC and RTC clocks are disabled. This allows to reduce global interrupt rate of idle system down to about 100 interrupts per core, permitting C3 and deeper C-states provide maximum CPU power efficiency.
* - fix formattingkmacy2009-02-151-68/+25
| | | | - fix types in ticks_to_system_time
* pass in smp_processor_id to identify the cpu in usekmacy2009-02-051-1/+1
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* adjust the way that idle happens so as to avoid missing timer interruptskmacy2009-02-051-64/+63
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* merge 186535, 186537, and 186538 from releng_7_xenkmacy2008-12-291-15/+18
| | | | | | | | | | | | | Log: - merge in latest xenbus from dfr's xenhvm - fix race condition in xs_read_reply by converting tsleep to mtx_sleep Log: unmask evtchn in bind_{virq, ipi}_to_irq Log: - remove code for handling case of not being able to sleep - eliminate tsleep - make sleeps atomic
* only call hardclock on cpu0kmacy2008-10-251-1/+4
| | | | pointed out by: Scott Long
* Fix IPI supportkmacy2008-10-231-18/+54
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* Add routine for initializing AP clockkmacy2008-10-211-16/+17
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* Compile fixes for xen build.kmacy2008-08-151-107/+25
| | | | MFC after: 1 month.
* Import i386 xen sub-arch files.kmacy2008-08-121-0/+976
MFC after: 2 weeks
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