summaryrefslogtreecommitdiff
path: root/drivers/hv/channel_mgmt.c
AgeCommit message (Collapse)Author
2017-03-27Merge 4.11-rc4 into char-misc-nextGreg Kroah-Hartman
We want the char-misc fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-17vmbus: make channel_message table constantStephen Hemminger
This table is immutable and should be const. Cleanup indentation and whitespace for this as well. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-16Drivers: hv: vmbus: Don't leak channel idsK. Y. Srinivasan
If we cannot allocate memory for the channel, free the relid associated with the channel. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Cc: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-16vmbus: remove hv_event_tasklet_disable/enableDexuan Cui
With the recent introduction of per-channel tasklet, we need to update the way we handle the 3 concurrency issues: 1. hv_process_channel_removal -> percpu_channel_deq vs. vmbus_chan_sched -> list_for_each_entry(..., percpu_list); 2. vmbus_process_offer -> percpu_channel_enq/deq vs. vmbus_chan_sched. 3. vmbus_close_internal vs. the per-channel tasklet vmbus_on_event; The first 2 issues can be handled by Stephen's recent patch "vmbus: use rcu for per-cpu channel list", and the third issue can be handled by calling tasklet_disable in vmbus_close_internal here. We don't need the original hv_event_tasklet_disable/enable since we now use per-channel tasklet instead of the previous per-CPU tasklet, and actually we must remove them due to the side effect now: vmbus_process_offer -> hv_event_tasklet_enable -> tasklet_schedule will start the per-channel callback prematurely, cauing NULL dereferencing (the channel may haven't been properly configured to run the callback yet). Fixes: 631e63a9f346 ("vmbus: change to per channel tasklet") Signed-off-by: Dexuan Cui <decui@microsoft.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-16vmbus: use rcu for per-cpu channel listStephen Hemminger
The per-cpu channel list is now referred to in the interrupt routine. This is mostly safe since the host will not normally generate an interrupt when channel is being deleted but if it did then there would be a use after free problem. To solve, this use RCU protection on ther per-cpu list. Fixes: 631e63a9f346 ("vmbus: change to per channel tasklet") Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-14vmbus: remove conditional locking of vmbus_writeStephen Hemminger
All current usage of vmbus write uses the acquire_lock flag, therefore having it be optional is unnecessary. This also fixes a sparse warning since sparse doesn't like when a function has conditional locking. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-14vmbus: add direct isr callback modeStephen Hemminger
Change the simple boolean batched_reading into a tri-value. For future NAPI support in netvsc driver, the callback needs to occur directly in interrupt handler. Batched mode is also changed to disable host interrupts immediately in interrupt routine (to avoid unnecessary host signals), and the tasklet is rescheduled if more data is detected. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-14vmbus: change to per channel taskletStephen Hemminger
Make the event handling tasklet per channel rather than per-cpu. This allows for better fairness when getting lots of data on the same cpu. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-14vmbus: put related per-cpu variable togetherStephen Hemminger
The hv_context structure had several arrays which were per-cpu and was allocating small structures (tasklet_struct). Instead use a single per-cpu array. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-31Drivers: hv: vmbus: Use all supported IC versions to negotiateAlex Ng
Previously, we were assuming that each IC protocol version was tied to a specific host version. For example, some Windows 10 preview hosts only support v3 TimeSync even though driver assumes v4 is supported by all Windows 10 hosts. The guest will stop trying to negotiate even though older supported versions may still be offered by the host. Make IC version negotiation more robust by going through all versions that are supported by the guest. Fixes: 3da0401b4d0e ("Drivers: hv: utils: Fix the mapping between host version and protocol to use") Reported-by: Rolf Neugebauer <rolf.neugebauer@docker.com> Signed-off-by: Alex Ng <alexng@messages.microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-20Drivers: hv: vmbus: Move the code to signal end of messageK. Y. Srinivasan
As part of the effort to separate out architecture specific code, move the code for signaling end of message. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-10Drivers: hv: vmbus: Fix a rescind handling bugK. Y. Srinivasan
The host can rescind a channel that has been offered to the guest and once the channel is rescinded, the host does not respond to any requests on that channel. Deal with the case where the guest may be blocked waiting for a response from the host. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Cc: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-10Drivers: hv: vmbus: Raise retry/wait limits in vmbus_post_msg()Vitaly Kuznetsov
DoS protection conditions were altered in WS2016 and now it's easy to get -EAGAIN returned from vmbus_post_msg() (e.g. when we try changing MTU on a netvsc device in a loop). All vmbus_post_msg() callers don't retry the operation and we usually end up with a non-functional device or crash. While host's DoS protection conditions are unknown to me my tests show that it can take up to 10 seconds before the message is sent so doing udelay() is not an option, we really need to sleep. Almost all vmbus_post_msg() callers are ready to sleep but there is one special case: vmbus_initiate_unload() which can be called from interrupt/NMI context and we can't sleep there. I'm also not sure about the lonely vmbus_send_tl_connect_request() which has no in-tree users but its external users are most likely waiting for the host to reply so sleeping there is also appropriate. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Cc: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-12-06hv: acquire vmbus_connection.channel_mutex in vmbus_free_channels()Vitaly Kuznetsov
"kernel BUG at drivers/hv/channel_mgmt.c:350!" is observed when hv_vmbus module is unloaded. BUG_ON() was introduced in commit 85d9aa705184 ("Drivers: hv: vmbus: add an API vmbus_hvsock_device_unregister()") as vmbus_free_channels() codepath was apparently forgotten. Fixes: 85d9aa705184 ("Drivers: hv: vmbus: add an API vmbus_hvsock_device_unregister()") Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Cc: <Stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-12-06hyperv: Fix spelling of HV_UNKOWNHaiyang Zhang
Changed it to HV_UNKNOWN Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-07Drivers: hv: vmbus: Base host signaling strictly on the ring stateK. Y. Srinivasan
One of the factors that can result in the host concluding that a given guest in mounting a DOS attack is if the guest generates interrupts to the host when the host is not expecting it. If these "spurious" interrupts reach a certain rate, the host can throttle the guest to minimize the impact. The host computation of the "expected number of interrupts" is strictly based on the ring transitions. Until the host logic is fixed, base the guest logic to interrupt solely on the ring state. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-27Drivers: hv: get rid of id in struct vmbus_channelVitaly Kuznetsov
The auto incremented counter is not being used anymore, get rid of it. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-07Drivers: hv: vmbus: suppress some "hv_vmbus: Unknown GUID" warningsDexuan Cui
Some VMBus devices are not needed by Linux guest[1][2], and, VMBus channels of Hyper-V Sockets don't really mean usual synthetic devices, so let's suppress the warnings for them. [1] https://support.microsoft.com/en-us/kb/2925727 [2] https://msdn.microsoft.com/en-us/library/jj980180(v=winembedded.81).aspx Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-02Drivers: hv: Introduce a policy for controlling channel affinityK. Y. Srinivasan
Introduce a mechanism to control how channels will be affinitized. We will support two policies: 1. HV_BALANCED: All performance critical channels will be dstributed evenly amongst all the available NUMA nodes. Once the Node is assigned, we will assign the CPU based on a simple round robin scheme. 2. HV_LOCALIZED: Only the primary channels are distributed across all NUMA nodes. Sub-channels will be in the same NUMA node as the primary channel. This is the current behaviour. The default policy will be the HV_BALANCED as it can minimize the remote memory access on NUMA machines with applications that span NUMA nodes. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31Drivers: hv: vmbus: Enable explicit signaling policy for NIC channelsK. Y. Srinivasan
For synthetic NIC channels, enable explicit signaling policy as netvsc wants to explicitly control when the host is to be signaled. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31Drivers: hv: vmbus: fix the race when querying & updating the percpu listDexuan Cui
There is a rare race when we remove an entry from the global list hv_context.percpu_list[cpu] in hv_process_channel_removal() -> percpu_channel_deq() -> list_del(): at this time, if vmbus_on_event() -> process_chn_event() -> pcpu_relid2channel() is trying to query the list, we can get the kernel fault. Similarly, we also have the issue in the code path: vmbus_process_offer() -> percpu_channel_enq(). We can resolve the issue by disabling the tasklet when updating the list. The patch also moves vmbus_release_relid() to a later place where the channel has been removed from the per-cpu and the global lists. Reported-by: Rolf Neugebauer <rolf.neugebauer@docker.com> Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-01Drivers: hv: vmbus: handle various crash scenariosVitaly Kuznetsov
Kdump keeps biting. Turns out CHANNELMSG_UNLOAD_RESPONSE is always delivered to the CPU which was used for initial contact or to CPU0 depending on host version. vmbus_wait_for_unload() doesn't account for the fact that in case we're crashing on some other CPU we won't get the CHANNELMSG_UNLOAD_RESPONSE message and our wait on the current CPU will never end. Do the following: 1) Check for completion_done() in the loop. In case interrupt handler is still alive we'll get the confirmation we need. 2) Read message pages for all CPUs message page as we're unsure where CHANNELMSG_UNLOAD_RESPONSE is going to be delivered to. We can race with still-alive interrupt handler doing the same, add cmpxchg() to vmbus_signal_eom() to not lose CHANNELMSG_UNLOAD_RESPONSE message. 3) Cleanup message pages on all CPUs. This is required (at least for the current CPU as we're clearing CPU0 messages now but we may want to bring up additional CPUs on crash) as new messages won't be delivered till we consume what's pending. On boot we'll place message pages somewhere else and we won't be able to read stale messages. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-01Drivers: hv: vmbus: avoid unneeded compiler optimizations in ↵Vitaly Kuznetsov
vmbus_wait_for_unload() Message header is modified by the hypervisor and we read it in a loop, we need to prevent compilers from optimizing accesses. There are no such optimizations at this moment, this is just a future proof. Suggested-by: Radim Krcmar <rkrcmar@redhat.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Radim Kr.má<rkrcmar@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-01Drivers: hv: vmbus: remove code duplication in message handlingVitaly Kuznetsov
We have 3 functions dealing with messages and they all implement the same logic to finalize reads, move it to vmbus_signal_eom(). Suggested-by: Radim Krcmar <rkrcmar@redhat.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Radim Kr.má<rkrcmar@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-01Drivers: hv: vmbus: avoid wait_for_completion() on crashVitaly Kuznetsov
wait_for_completion() may sleep, it enables interrupts and this is something we really want to avoid on crashes because interrupt handlers can cause other crashes. Switch to the recently introduced vmbus_wait_for_unload() doing busy wait instead. Reported-by: Radim Krcmar <rkrcmar@redhat.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Radim Kr.má<rkrcmar@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07Drivers: hv: vmbus: Give control over how the ring access is serializedK. Y. Srinivasan
On the channel send side, many of the VMBUS device drivers explicity serialize access to the outgoing ring buffer. Give more control to the VMBUS device drivers in terms how to serialize accesss to the outgoing ring buffer. The default behavior will be to aquire the ring lock to preserve the current behavior. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07Drivers: hv: vmbus: add an API vmbus_hvsock_device_unregister()Dexuan Cui
The hvsock driver needs this API to release all the resources related to the channel. Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07Drivers: hv: vmbus: add a per-channel rescind callbackDexuan Cui
This will be used by the coming hv_sock driver. Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07Drivers: hv: vmbus: define a new VMBus message type for hvsockDexuan Cui
A function to send the type of message is also added. The coming net/hvsock driver will use this function to proactively request the host to offer a VMBus channel for a new hvsock connection. Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07Drivers: hv: vmbus: avoid scheduling in interrupt context in ↵Vitaly Kuznetsov
vmbus_initiate_unload() We have to call vmbus_initiate_unload() on crash to make kdump work but the crash can also be happening in interrupt (e.g. Sysrq + c results in such) where we can't schedule or the following will happen: [ 314.905786] bad: scheduling from the idle thread! Just skipping the wait (and even adding some random wait here) won't help: to make host-side magic working we're supposed to receive CHANNELMSG_UNLOAD (and actually confirm the fact that we received it) but we can't use interrupt-base path (vmbus_isr()-> vmbus_on_msg_dpc()). Implement a simple busy wait ignoring all the other messages and use it if we're in an interrupt context. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07Drivers: hv: vmbus: avoid infinite loop in init_vp_index()Vitaly Kuznetsov
When we pick a CPU to use for a new subchannel we try find a non-used one on the appropriate NUMA node, we keep track of them with the primary->alloced_cpus_in_node mask. Under normal circumstances we don't run out of available CPUs but it is possible when we we don't initialize some cpus in Linux, e.g. when we boot with 'nr_cpus=' limitation. Avoid the infinite loop in init_vp_index() by checking that we still have non-used CPUs in the alloced_cpus_in_node mask and resetting it in case we don't. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07Drivers: hv: vmbus: Add vendor and device atttributesK. Y. Srinivasan
Add vendor and device attributes to VMBUS devices. These will be used by Hyper-V tools as well user-level RDMA libraries that will use the vendor/device tuple to discover the RDMA device. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-21Drivers: hv: vmbus: Treat Fibre Channel devices as performance criticalK. Y. Srinivasan
For performance critical devices, we distribute the incoming channel interrupt load across available CPUs in the guest. Include Fibre channel devices in the set of devices for which we would distribute the interrupt load. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14Drivers: hv: vmbus: channge vmbus_connection.channel_lock to mutexDexuan Cui
spinlock is unnecessary here. mutex is enough. Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14Drivers: hv: vmbus: release relid on error in vmbus_process_offer()Dexuan Cui
We want to simplify vmbus_onoffer_rescind() by not invoking hv_process_channel_removal(NULL, ...). Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14Drivers: hv: vmbus: fix rescind-offer handling for device without a driverDexuan Cui
In the path vmbus_onoffer_rescind() -> vmbus_device_unregister() -> device_unregister() -> ... -> __device_release_driver(), we can see for a device without a driver loaded: dev->driver is NULL, so dev->bus->remove(dev), namely vmbus_remove(), isn't invoked. As a result, vmbus_remove() -> hv_process_channel_removal() isn't invoked and some cleanups(like sending a CHANNELMSG_RELID_RELEASED message to the host) aren't done. We can demo the issue this way: 1. rmmod hv_utils; 2. disable the Heartbeat Integration Service in Hyper-V Manager and lsvmbus shows the device disappears. 3. re-enable the Heartbeat in Hyper-V Manager and modprobe hv_utils, but lsvmbus shows the device can't appear again. This is because, the host thinks the VM hasn't released the relid, so can't re-offer the device to the VM. We can fix the issue by moving hv_process_channel_removal() from vmbus_close_internal() to vmbus_device_release(), since the latter is always invoked on device_unregister(), whether or not the dev has a driver loaded. Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14Drivers: hv: vmbus: Use uuid_le_cmp() for comparing GUIDsK. Y. Srinivasan
Use uuid_le_cmp() for comparing GUIDs. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14Drivers: hv: vmbus: Use uuid_le type consistentlyK. Y. Srinivasan
Consistently use uuid_le type in the Hyper-V driver code. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14drivers:hv: Define the channel type for Hyper-V PCI Express pass-throughJake Oshins
This defines the channel type for PCI front-ends in Hyper-V VMs. Signed-off-by: Jake Oshins <jakeo@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-09-20Drivers: hv: vmbus: fix init_vp_index() for reloading hv_netvscDexuan Cui
This fixes the recent commit 3b71107d73b16074afa7658f3f0fcf837aabfe24: Drivers: hv: vmbus: Further improve CPU affiliation logic Without the fix, reloading hv_netvsc hangs the guest. Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-05Drivers: hv: vmbus: Further improve CPU affiliation logicDexuan Cui
Keep track of CPU affiliations of sub-channels within the scope of the primary channel. This will allow us to better distribute the load amongst available CPUs. Signed-off-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-05Drivers: hv: vmbus: Improve the CPU affiliation for channelsK. Y. Srinivasan
The current code tracks the assigned CPUs within a NUMA node in the context of the primary channel. So, if we have a VM with a single NUMA node with 8 VCPUs, we may end up unevenly distributing the channel load. Fix the issue by tracking affiliations globally. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-04Drivers: hv: vmbus: Consider ND NIC in binding channels to CPUsK. Y. Srinivasan
We cycle through all the "high performance" channels to distribute load across the available CPUs. Process the NetworkDirect as a high performance device. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-04Drivers: hv: vmbus: don't send CHANNELMSG_UNLOAD on pre-Win2012R2 hostsVitaly Kuznetsov
Pre-Win2012R2 hosts don't properly handle CHANNELMSG_UNLOAD and wait_for_completion() hangs. Avoid sending such request on old hosts. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-06-01Drivers: hv: vmbus: Implement NUMA aware CPU affinity for channelsK. Y. Srinivasan
Channels/sub-channels can be affinitized to VCPUs in the guest. Implement this affinity in a way that is NUMA aware. The current protocol distributed the primary channels uniformly across all available CPUs. The new protocol is NUMA aware: primary channels are distributed across the available NUMA nodes while the sub-channels within a primary channel are distributed amongst CPUs within the NUMA node assigned to the primary channel. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-06-01Drivers: hv: vmbus: Use the vp_index map even for channels bound to CPU 0K. Y. Srinivasan
Map target_cpu to target_vcpu using the mapping table. We should use the mapping table to transform guest CPU ID to VP Index as is done for the non-performance critical channels. While the value CPU 0 is special and will map to VP index 0, it is good to be consistent. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-24Drivers: hv: vmbus: distribute subchannels among all vcpusVitaly Kuznetsov
Primary channels are distributed evenly across all vcpus we have. When the host asks us to create subchannels it usually makes us num_cpus-1 offers and we are supposed to distribute the work evenly among the channel itself and all its subchannels. Make sure they are all assigned to different vcpus. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-24Drivers: hv: vmbus: move init_vp_index() call to vmbus_process_offer()Vitaly Kuznetsov
We need to call init_vp_index() after we added the channel to the appropriate list (global or subchannel) to be able to use this information when assigning the channel to the particular vcpu. To do so we need to move a couple of functions around. The only real change is the init_vp_index() call. This is a small refactoring without a functional change. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-24Drivers: hv: vmbus: decrease num_sc on subchannel removalVitaly Kuznetsov
It is unlikely that that host will ask us to close only one subchannel for a device but let's be consistent. Do both num_sc++ and num_sc-- with channel->lock to be on the safe side. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-24Drivers: hv: vmbus: unify calls to percpu_channel_enq()Vitaly Kuznetsov
Remove some code duplication, no functional change intended. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>