We'll remove the per-channel control_work_queue because it can't properly
do serialization of message handling, e.g., when there are 2 NIC devices,
vmbus_channel_on_offer() -> hv_queue_work_item() has a race condition:
for an SMP VM, vmbus_channel_process_offer() can run concurrently on
different CPUs and if the second NIC's
vmbus_channel_process_offer() -> hv_vmbus_child_device_register() runs
first, the second NIC's name will be hn0 and the first NIC's name will
be hn1!
We can fix the race condition by removing the per-channel control_work_queue
and run all the message handlers in the global
hv_vmbus_g_connection.work_queue -- we'll do this in the next patch.
With the coming next patch, we have to run the non-blocking handlers
directly in the kernel thread vmbus_msg_swintr(), because the special
handling of sub-channel: when a sub-channel (e.g., of the storvsc driver)
is received and being handled in vmbus_channel_on_offer() running on the
global hv_vmbus_g_connection.work_queue, vmbus_channel_process_offer()
invokes channel->sc_creation_callback, i.e., storvsc_handle_sc_creation,
and the callback will invoke hv_vmbus_channel_open() -> hv_vmbus_post_message
and expect a further reply from the host, but the handling of the further
messag can't be done because the current message's handling hasn't finished
yet; as result, hv_vmbus_channel_open() -> sema_timedwait() will time out
and th device can't work.
Also renamed the handler type from hv_pfn_channel_msg_handler to
vmbus_msg_handler: the 'pfn' and 'channel' in the old name make no sense.
Submitted by: Dexuan Cui <decui microsoft com>
Reviewed by: royger
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D4596
Now vmbus_channel_on_offer() -> vmbus_channel_process_offer() can
safely run on the global hv_vmbus_g_connection.work_queue now.
We remove the per-channel control_work_queue to achieve the proper
serialization of the message handling.
I removed the bogus TODO in vmbus_channel_on_offer(): a vmbus offer
can only come from the parent partition, i.e., the host.
PR: kern/205156
Submitted by: Dexuan Cui <decui microsoft com>
Reviewed by: Howard Su <howard0su gmail com>, delphij
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D4597
- Vmbus multi channel support.
- Vector interrupt support.
- Signal optimization.
- Storvsc driver performance improvement.
- Scatter and gather support for storvsc driver.
- Minor bug fix for KVP driver.
Thanks royger, jhb and delphij from FreeBSD community for the reviews
and comments. Also thanks Hovy Xu from NetApp for the contributions to
the storvsc driver.
PR: 195238
Submitted by: whu
Reviewed by: royger, jhb, delphij
Approved by: royger
MFC after: 2 weeks
Relnotes: yes
Sponsored by: Microsoft OSTC
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.
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs, grehan
Approved by: re (gjb)
sys/sys/systm.h:
* Add a new VM_GUEST type, VM_GUEST_HV (HyperV guest).
sys/dev/hyperv/vmbus/hv_vmbus_drv_freebsd.c:
sys/dev/hyperv/vmbus/hv_hv.c:
sys/dev/hyperv/stordisengage/hv_ata_pci_disengage.c:
* Set vm_guest to VM_GUEST_HV and use that on other HyperV related
devices instead of cloning the cpuid hypervisor check.
* Cleanup the vmbus_identify function.
union members in strict C99, by giving them names. While here, add some
FreeBSD keywords where they were missing.
Approved by: re (gjb)
Reviewed by: grehan
aware drivers on Xen hypervisors that advertise support for some
HyperV features.
x86/xen/hvm.c:
When running in HVM mode on a Xen hypervisor, set vm_guest
to VM_GUEST_XEN so other virtualization aware components in
the FreeBSD kernel can detect this mode is active.
dev/hyperv/vmbus/hv_hv.c:
Use vm_guest to ignore Xen's HyperV emulation when Xen is
detected and Xen PV drivers are active.
Reported by: Shanker Balan
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs
Approved by: re (Xen blanket)
be pulled into FreeBSD. From now, FreeBSD will be considered the
upstream repo.
First step: move the drivers away from the contrib area and into
the base system.
A follow-on commit will include the drivers in the amd64 GENERIC kernel.
