Current FreeBSD netback names the interface with xnb<device unit>, but
this is not suitable for usage with the Xen toolstack, which expects
something similar to <prefix><domid><handle>. In order to solve this,
change the netback naming convention to use xnb<domid>.<handle>.
Sponsored by: Citrix Systems R&D
dev/xen/netback/netback.c:
- Change netback to use the nomenclature stated above.
This device is only attached to priviledged domains, and allows the
toolstack to interact with Xen. The two functions of the privcmd
interface is to allow the execution of hypercalls from user-space, and
the mapping of foreign domain memory.
Sponsored by: Citrix Systems R&D
i386/include/xen/hypercall.h:
amd64/include/xen/hypercall.h:
- Introduce a function to make generic hypercalls into Xen.
xen/interface/xen.h:
xen/interface/memory.h:
- Import the new hypercall XENMEM_add_to_physmap_range used by
auto-translated guests to map memory from foreign domains.
dev/xen/privcmd/privcmd.c:
- This device has the following functions:
- Allow user-space applications to make hypercalls into Xen.
- Allow user-space applications to map memory from foreign domains,
this is accomplished using the newly introduced hypercall
(XENMEM_add_to_physmap_range).
xen/privcmd.h:
- Public ioctl interface for the privcmd device.
x86/xen/hvm.c:
- Remove declaration of hypercall_page, now it's declared in
hypercall.h.
conf/files:
- Add the privcmd device to the build process.
The user-space event channel device is used by applications to receive
and send event channel interrupts. This device is based on the Linux
evtchn device.
Sponsored by: Citrix Systems R&D
xen/evtchn/evtchn_dev.c:
- Remove the old event channel device, which was already disabled in
the build system.
dev/xen/evtchn/evtchn_dev.c:
- Import a new event channel device based on the one present in
Linux.
- This device allows the following operations:
- Bind VIRQ event channels (ioctl).
- Bind regular event channels (ioctl).
- Create and bind new event channels (ioctl).
- Unbind event channels (ioctl).
- Send notifications to event channels (ioctl).
- Reset the device shared memory ring (ioctl).
- Unmask event channels (write).
- Receive event channel upcalls (read).
- The new code is MP safe, and can be used concurrently.
conf/files:
- Add the new device to the build system.
- Wrong integer type was specified.
- Wrong or missing "access" specifier. The "access" specifier
sometimes included the SYSCTL type, which it should not, except for
procedural SYSCTL nodes.
- Logical OR where binary OR was expected.
- Properly assert the "access" argument passed to all SYSCTL macros,
using the CTASSERT macro. This applies to both static- and dynamically
created SYSCTLs.
- Properly assert the the data type for both static and dynamic
SYSCTLs. In the case of static SYSCTLs we only assert that the data
pointed to by the SYSCTL data pointer has the correct size, hence
there is no easy way to assert types in the C language outside a
C-function.
- Rewrote some code which doesn't pass a constant "access" specifier
when creating dynamic SYSCTL nodes, which is now a requirement.
- Updated "EXAMPLES" section in SYSCTL manual page.
MFC after: 3 days
Sponsored by: Mellanox Technologies
Fix a problem where the blockback driver could run out of requests,
despite the fact that we allocate enough request and reqlist
structures to satisfy the maximum possible number of requests.
The problem was that we were sending responses back to the other
end (blockfront) before freeing resources. The Citrix Windows
driver is pretty agressive about queueing, and would queue more I/O
to us immediately after we sent responses to it. We would run into
a resource shortage and stall out I/O until we freed resources.
It isn't clear whether the request shortage condition was an
indirect cause of the I/O hangs we've been seeing between Windows
with the Citrix PV drivers and FreeBSD's blockback, but the above
problem is certainly a bug.
Sponsored by: Spectra Logic
Submitted by: ken
Reviewed by: royger
dev/xen/blkback/blkback.c:
- Break xbb_send_response() into two sub-functions,
xbb_queue_response() and xbb_push_responses().
Remove xbb_send_response(), because it is no longer
used.
- Adjust xbb_complete_reqlist() so that it calls the
two new functions, and holds the mutex around both
calls. The mutex insures that another context
can't come along and push responses before we've
freed our resources.
- Change xbb_release_reqlist() so that it requires
the mutex to be held instead of acquiring the mutex
itself. Both callers could easily hold the mutex
while calling it, and one really needs to hold the
mutex during the call.
- Add two new counters, accessible via sysctl
variables. The first one counts the number of
I/Os that are queued and waiting to be pushed
(reqs_queued_for_completion). The second one
(reqs_completed_with_error) counts the number of
requests we've completed with an error status.
Using realmem on PVH is not realiable, since in this case the realmem value
is computed from Maxmem, which contains the higher memory address found. Use
HYPERVISOR_start_info->nr_pages instead, which is set by the hypervisor and
contains the exact number of memory pages assigned to the domain.
Sponsored by: Citrix Systems R&D
This device is used by the user-space daemon that runs xenstore
(xenstored). It allows xenstored to map the xenstore memory page, and
reports the event channel xenstore is using.
Sponsored by: Citrix Systems R&D
dev/xen/xenstore/xenstored_dev.c:
- Add the xenstored character device that's used to map the xenstore
memory into user-space, and to report the event channel used by
xenstore.
conf/files:
- Add the device to the build process.
Convert the xenstore user-space device (/dev/xen/xenstore) to a device
using the newbus interface. This allows us to make the device
initialization dependant on the initialization of xenstore itself in
the kernel.
Sponsored by: Citrix Systems R&D
dev/xen/xenstore/xenstore.c:
- Convert to a newbus device, this removes the xs_dev_init function.
xen/xenstore/xenstore_internal.h:
- Remove xs_dev_init prototype.
dev/xen/xenstore/xenstore.c:
- Don't call xs_dev_init anymore, the device will attach itself when
xenstore is started.
The xenstore related devices in the kernel cannot be started until
xenstored is running, which will happen later in the Dom0 case. If
start_info_t doesn't contain a valid xenstore event channel, defer all
xenstore related devices attachment to later.
Sponsored by: Citrix Systems R&D
dev/xen/xenstore/xenstore.c:
- Prevent xenstore from trying to attach it's descendant devices if
xenstore is not initialized.
- Add a callback in the xenstore interrupt filter that will trigger
the plug of xenstore descendant devices on the first received
interrupt. This interrupt is generated when xenstored attaches to
the event channel, and serves as a notification that xenstored is
running.
Move xenstore related devices (xenstore.c and xenstore_dev.c) from
xen/xenstore to dev/xen/xenstore. This is just code motion, no
functional changes.
Sponsored by: Citrix Systems R&D
This is done so we can prevent the Xen Balloon driver from attaching
before xenstore is setup.
Sponsored by: Citrix Systems R&D
dev/xen/balloon/balloon.c:
- Make xen balloon a driver that depends on xenstore.
The current TSO limitation feature only takes the total number of
bytes in an mbuf chain into account and does not limit by the number
of mbufs in a chain. Some kinds of hardware is limited by two
factors. One is the fragment length and the second is the fragment
count. Both of these limits need to be taken into account when doing
TSO. Else some kinds of hardware might have to drop completely valid
mbuf chains because they cannot loaded into the given hardware's DMA
engine. The new way of doing TSO limitation has been made backwards
compatible as input from other FreeBSD developers and will use
defaults for values not set.
Reviewed by: adrian, rmacklem
Sponsored by: Mellanox Technologies
MFC after: 1 week
The current TSO limitation feature only takes the total number of
bytes in an mbuf chain into account and does not limit by the number
of mbufs in a chain. Some kinds of hardware is limited by two
factors. One is the fragment length and the second is the fragment
count. Both of these limits need to be taken into account when doing
TSO. Else some kinds of hardware might have to drop completely valid
mbuf chains because they cannot loaded into the given hardware's DMA
engine. The new way of doing TSO limitation has been made backwards
compatible as input from other FreeBSD developers and will use
defaults for values not set.
MFC after: 1 week
Sponsored by: Mellanox Technologies
Current busdma code for unmapped bios will not properly align the segment
size, causing corruption on blkfront devices. Revert the commit until
busdma code is fixed.
Reported by: mav
MFC after: 1 day
Fix some frees incorrectly assigned to M_XENBUS when the memory is
allocated with M_XENSTORE.
Sponsored by: Citrix Systems R&D
MFC after: 1 week
dev/xen/blkback/blkback.c:
- Fix incorrect frees.
This patch contains the following fixes for netback:
- Only unbind the evtchn if it has been bound.
- Set xnb->bridge to NULL after free to prevent double-freeing it.
- Set the MAC address for the host-facing interface to a dummy value.
Sponsored by: Citrix Systems R&D
dev/xen/netback/netback.c:
- Prevent trying to unbind if the evtchn has not been bounded.
- Prevent double-freeing xnb->bridge.
- Set the MAC address of the host-facing interface to a dummy value,
so it can work when the interface is added to a bridge.
Using unmapped IO is really beneficial when running inside of a VM,
since it avoids IPIs to other vCPUs in order to invalidate the
mappings.
This patch adds unmapped IO support to blkfront. The following tests
results have been obtained when running on a Xen host without HAP:
PVHVM
3165.84 real 6354.17 user 4483.32 sys
PVHVM with unmapped IO
2099.46 real 4624.52 user 2967.38 sys
This is because when running using shadow page tables TLB flushes and
range invalidations are much more expensive, so using unmapped IO
provides a very important performance boost.
Sponsored by: Citrix Systems R&D
Tested by: robak
MFC after: 1 week
PR: 191173
dev/xen/blkfront/blkfront.c:
- Add and announce support for unmapped IO.
Minor fixes to make the Xen Dom0 console work. This includes always
returning there's pending input in xencons_has_input, because on Dom0
there's no shared ring and we cannot test the indexes. The second
fix is to use the CONSOLEIO_read hypercall in order to read input
data from the Xen console.
Sponsored by: Citrix Systems R&D
dev/xen/console/xencons_ring.c:
- Always return true in xencons_has_input for Dom0.
- Implement Dom0 console support for xencons_handle_input.
Prevent the Xen and VirtIO balloon drivers from marking pages as
wired. This prevents them from increasing the system wired page count,
which can lead to mlock failing because of hitting the limit in
vm.max_wired.
In the Xen case make sure pages are zeroed before giving them back to
the hypervisor, or else we might be leaking data. Also remove the
balloon_{append/retrieve} and link pages directly into the
ballooned_pages queue using the plinks.q field in the page struct.
Sponsored by: Citrix Systems R&D
Reviewed by: kib, bryanv
Approved by: gibbs
dev/virtio/balloon/virtio_balloon.c:
- Don't allocate pages with VM_ALLOC_WIRED.
dev/xen/balloon/balloon.c:
- Don't allocate pages with VM_ALLOC_WIRED.
- Make sure pages are zeroed before giving them back to the
hypervisor.
- Remove the balloon_entry struct and the balloon_{append/retrieve}
functions and use the page plinks.q entry to link the pages
directly into the ballooned_pages queue.
the queue where to enqueue pages that are going to be unwired.
- Add stronger checks to the enqueue/dequeue for the pagequeues when
adding and removing pages to them.
Of course, for unmanaged pages the queue parameter of vm_page_unwire() will
be ignored, just as the active parameter today.
This makes adding new pagequeues quicker.
This change effectively modifies the KPI. __FreeBSD_version will be,
however, bumped just when the full cache of free pages will be
evicted.
Sponsored by: EMC / Isilon storage division
Reviewed by: alc
Tested by: pho
Switch the initialization of gnttab to use an unused physical memory
range for both PVHVM and PVH.
In the past PVHVM was using the xenpci BAR, but there's no reason to
do that, and in fact FreeBSD was probably doing it because it was the
way it was done in Windows, were drivers cannot probably request for
unused physical memory ranges, but it was never enforced in the
hypervisor.
Sponsored by: Citrix Systems R&D
Approved by: gibbs
xen/gnttab.c:
- Allocate contiguous physical memory for grant table frames for both
PVHVM and PVH.
- Since gnttab is not a device, use the xenpv device in order to
request for this allocation.
dev/xen/xenpci/xenpcivar.h:
dev/xen/xenpci/xenpci.c:
- Remove the now unused xenpci_alloc_space and xenpci_alloc_space_int
functions.
xen/gnttab.h:
- Change the prototype of gnttab_init and gnttab_resume, that now
takes a device_t parameter.
dev/xen/control/control.c:
x86/xen/xenpv.c:
- Changes to accomodate the new prototype of gnttab_init and
gnttab_resume.
Add the PV shutdown hook to PVH.
Sponsored by: Citrix Systems R&D
Approved by: gibbs
dev/xen/control/control.c:
- Make xen_pv_shutdown_final available on XENHVM builds.
- Register the Xen PV shutdown hook for PVH guests.
Create a dummy bus so top level Xen devices can attach to it (instead
of attaching directly to the nexus). This allows to have all the Xen
related devices grouped under a single bus.
Sponsored by: Citrix Systems R&D
Approved by: gibbs
x86/xen/xenpv.c:
- Attach the xenpv bus when running as a Xen guest.
- Attach the ISA bus if needed, in order to attach syscons.
conf/files.amd6:
conf/files.i386:
- Include the xenpv.c file in the build of i386/amd64 kernels using
XENHVM.
dev/xen/console/console.c:
dev/xen/timer/timer.c:
xen/xenstore/xenstore.c:
- Attach to the xenpv bus instead of the Nexus.
dev/xen/xenpci/xenpci.c:
- Xen specific devices on PVHVM guests are no longer attached to the
xenpci device, they are instead attached to the xenpv bus, remove
the now unused methods.
Replace usage of db_active in Xen console with kdb_active.
Reported by: Andrzej Tobola <ato@iem.pw.edu.pl>
Approved by: gibbs
Sponsored by: Citrix Systems R&D
When running as a PVH guest, there's no emulated i8254, so we need to
use the Xen PV timer as the early source for DELAY. This change allows
for different implementations of the early DELAY function and
implements a Xen variant for it.
Approved by: gibbs
Sponsored by: Citrix Systems R&D
dev/xen/timer/timer.c:
dev/xen/timer/timer.h:
- Implement Xen early delay functions using the PV timer and declare
them.
x86/include/init.h:
- Add hooks for early clock source initialization and early delay
functions.
i386/i386/machdep.c:
pc98/pc98/machdep.c:
amd64/amd64/machdep.c:
- Set early delay hooks to use the i8254 on bare metal.
- Use clock_init (that will in turn make use of init_ops) to
initialize the early clock source.
amd64/include/clock.h:
i386/include/clock.h:
- Declare i8254_delay and clock_init.
i386/xen/clock.c:
- Rename DELAY to i8254_delay.
x86/isa/clock.c:
- Introduce clock_init that will take care of initializing the early
clock by making use of the init_ops hooks.
- Move non ISA related delay functions to the newly introduced delay
file.
x86/x86/delay.c:
- Add moved delay related functions.
- Implement generic DELAY function that will use the init_ops hooks.
x86/xen/pv.c:
- Set PVH hooks for the early delay related functions in init_ops.
conf/files.amd64:
conf/files.i386:
conf/files.pc98:
- Add delay.c to the kernel build.
This should not introduce any functional change, and makes the
functions suitable to be called before we have actually mapped the
vcpu_info struct on a per-cpu basis.
Approved by: gibbs
Sponsored by: Citrix Systems R&D
dev/xen/timer/timer.c:
- Remove citrical_{enter/exit}, the clock code will already be called
with preemption disabled when needed. Add a comment to that regard
in xentimer_get_timecount.
- Allow xen_fetch_vcpu_time to be called with a specifc vcpu_info
that will be used to fetch current time.
- Assert that xentimer_et_start will always be called with preemption
disabled.
This adds and enables the PV console used on XEN kernels to
GENERIC/XENHVM kernels in order for it to be used on PVH.
Approved by: gibbs
Sponsored by: Citrix Systems R&D
dev/xen/console/console.c:
- Define console_page.
- Move xc_printf debug function from i386 XEN code to generic console
code.
- Rework xc_printf.
- Use xen_initial_domain instead of open-coded checks for Dom0.
- Gate the attach of the PV console to PV(H) guests.
dev/xen/console/xencons_ring.c:
- Allow the PV Xen console to output earlier by directly signaling
the event channel in start_info if the event channel is not yet
initialized.
- Use HYPERVISOR_start_info instead of xen_start_info.
i386/include/xen/xen-os.h:
- Remove prototype for xc_printf since it's now declared in global
xen-os.h
i386/xen/xen_machdep.c:
- Remove previous version of xc_printf.
- Remove definition of console_page (now it's defined in the console
itself).
- Fix some printf formatting errors.
x86/xen/pv.c:
- Add some early boot debug messages using xc_printf.
- Set console_page based on the value passed in start_info.
xen/xen-os.h:
- Declare console_page and add prototype for xc_printf.
In its stead use the Solaris / illumos approach of emulating '-' (dash)
in probe names with '__' (two consecutive underscores).
Reviewed by: markj
MFC after: 3 weeks
option, unbreak the lock tracing release semantic by embedding
calls to LOCKSTAT_PROFILE_RELEASE_LOCK() direclty in the inlined
version of the releasing functions for mutex, rwlock and sxlock.
Failing to do so skips the lockstat_probe_func invokation for
unlocking.
- As part of the LOCKSTAT support is inlined in mutex operation, for
kernel compiled without lock debugging options, potentially every
consumer must be compiled including opt_kdtrace.h.
Fix this by moving KDTRACE_HOOKS into opt_global.h and remove the
dependency by opt_kdtrace.h for all files, as now only KDTRACE_FRAMES
is linked there and it is only used as a compile-time stub [0].
[0] immediately shows some new bug as DTRACE-derived support for debug
in sfxge is broken and it was never really tested. As it was not
including correctly opt_kdtrace.h before it was never enabled so it
was kept broken for a while. Fix this by using a protection stub,
leaving sfxge driver authors the responsibility for fixing it
appropriately [1].
Sponsored by: EMC / Isilon storage division
Discussed with: rstone
[0] Reported by: rstone
[1] Discussed with: philip
sys/dev/xen/balloon/balloon.c:
Remove unused and commented out code.
Fix deadlock caused by performing a sleepable malloc
while holding the balloon mutex.
Perform proper accounting of the memory used by the domain.
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs
MFC after: 2 days
makes FreeBSD halt but not poweroff (as expected when issuing a
shutdown from the VM manager). Fix this by using the same handler
for both "halt" and "poweroff".
NB: The "halt" signal seems to be used on XenServer only. The OSS
Xen toolstack (xl) uses "poweroff" instead.
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs
MFC after: 2 days
resist easy conversion since they implement a great deal of their attach
logic inside probe(). Some of this could be fixed by moving it to attach(),
but some requires something more subtle than BUS_PROBE_NOWILDCARD.
This shuld have been a problem since r230587. Not exactly sure why it
was not detected the last weeks with the tinderbox. I would assume
r255744 is what started to cause it.
MFC after: 1 week
prior releases.
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs
Approved by: re (gjb)
sys/dev/xen/blkfront/blkfront.c:
On XenServer versions up to an including 6.2, paravirtualized
CDROM support is broken. When running in an HVM domain,
ignore paravirtualized instances of CDROM media, and instead
rely on native drivers attaching to emulated hardware. This
functions correctly on all currently known Xen based
platforms.
field. Perform vcpu enumeration for Xen PV and HVM environments
and convert all Xen drivers to use vcpu_id instead of a hard coded
assumption of the mapping algorithm (acpi or apic ID) in use.
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs
Approved by: re (blanket Xen)
amd64/include/pcpu.h:
i386/include/pcpu.h:
Add vcpu_id to the amd64 and i386 pcpu structures.
dev/xen/timer/timer.c
x86/xen/xen_intr.c
Use new vcpu_id instead of assuming acpi_id == vcpu_id.
i386/xen/mp_machdep.c:
i386/xen/mptable.c
x86/xen/hvm.c:
Perform Xen HVM and Xen full PV vcpu_id mapping.
x86/xen/hvm.c:
x86/acpica/madt.c
Change SYSINIT ordering of acpi CPU enumeration so that it
is guaranteed to be available at the time of Xen HVM vcpu
id mapping.
Xen PVHVM guest.
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs
Approved by: re (blanket Xen)
MFC after: 2 weeks
sys/amd64/amd64/mp_machdep.c:
sys/i386/i386/mp_machdep.c:
- Make sure that are no MMU related IPIs pending on migration.
- Reset pending IPI_BITMAP on resume.
- Init vcpu_info on resume.
sys/amd64/include/intr_machdep.h:
sys/i386/include/intr_machdep.h:
sys/x86/acpica/acpi_wakeup.c:
sys/x86/x86/intr_machdep.c:
sys/x86/isa/atpic.c:
sys/x86/x86/io_apic.c:
sys/x86/x86/local_apic.c:
- Add a "suspend_cancelled" parameter to pic_resume(). For the
Xen PIC, restoration of interrupt services differs between
the aborted suspend and normal resume cases, so we must provide
this information.
sys/dev/acpica/acpi_timer.c:
sys/dev/xen/timer/timer.c:
sys/timetc.h:
- Don't swap out "suspend safe" timers across a suspend/resume
cycle. This includes the Xen PV and ACPI timers.
sys/dev/xen/control/control.c:
- Perform proper suspend/resume process for PVHVM:
- Suspend all APs before going into suspension, this allows us
to reset the vcpu_info on resume for each AP.
- Reset shared info page and callback on resume.
sys/dev/xen/timer/timer.c:
- Implement suspend/resume support for the PV timer. Since FreeBSD
doesn't perform a per-cpu resume of the timer, we need to call
smp_rendezvous in order to correctly resume the timer on each CPU.
sys/dev/xen/xenpci/xenpci.c:
- Don't reset the PCI interrupt on each suspend/resume.
sys/kern/subr_smp.c:
- When suspending a PVHVM domain make sure there are no MMU IPIs
in-flight, or we will get a lockup on resume due to the fact that
pending event channels are not carried over on migration.
- Implement a generic version of restart_cpus that can be used by
suspended and stopped cpus.
sys/x86/xen/hvm.c:
- Implement resume support for the hypercall page and shared info.
- Clear vcpu_info so it can be reset by APs when resuming from
suspension.
sys/dev/xen/xenpci/xenpci.c:
sys/x86/xen/hvm.c:
sys/x86/xen/xen_intr.c:
- Support UP kernel configurations.
sys/x86/xen/xen_intr.c:
- Properly rebind per-cpus VIRQs and IPIs on resume.
Properly round-trip the "operation code" for client requests.
sys/dev/xen/blkback/blkback.c:
In xbb_dispatch_dev() when processing a flush request,
correctly set bio->bio_caller1 to the request list (not
bare request) for the operation, as is expected by the
completion handler xbb_bio_done().
In xbb_get_resources(), initialize "operation" in the
driver's internal request object from the client's "ring
request", so it is correct when used to populate the reply
when this operation completes.
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs
Initialize the request id for requests in xbb_get_resources()
instead of its previous location in xbb_dispatch_io(). This
guarantees that all request types (e.g. BLKIF_OP_FLUSH_DISKCACHE)
have the front-end specified id recorded.
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
value. Some hosts do not publish "extended" disk IDs via virtual-device in
an attempt to avoid confusing old blkfront drivers, and without this change
we failed to attach such disks.
In particular, this commit allows all 24 ephemeral disks on EC2 hs1.8xlarge
instances to be used, instead of only the first 15.
MFC after: 3 days
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
