linux/drivers/hv/hyperv_vmbus.h

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/* SPDX-License-Identifier: GPL-2.0-only */
/*
*
* Copyright (c) 2011, Microsoft Corporation.
*
* Authors:
* Haiyang Zhang <haiyangz@microsoft.com>
* Hank Janssen <hjanssen@microsoft.com>
* K. Y. Srinivasan <kys@microsoft.com>
*/
#ifndef _HYPERV_VMBUS_H
#define _HYPERV_VMBUS_H
#include <linux/list.h>
#include <asm/sync_bitops.h>
#include <asm/hyperv-tlfs.h>
#include <linux/atomic.h>
#include <linux/hyperv.h>
#include <linux/interrupt.h>
#include "hv_trace.h"
/*
* Timeout for services such as KVP and fcopy.
*/
#define HV_UTIL_TIMEOUT 30
/*
* Timeout for guest-host handshake for services.
*/
#define HV_UTIL_NEGO_TIMEOUT 55
/* Definitions for the monitored notification facility */
union hv_monitor_trigger_group {
u64 as_uint64;
struct {
u32 pending;
u32 armed;
};
};
struct hv_monitor_parameter {
union hv_connection_id connectionid;
u16 flagnumber;
u16 rsvdz;
};
union hv_monitor_trigger_state {
u32 asu32;
struct {
u32 group_enable:4;
u32 rsvdz:28;
};
};
/* struct hv_monitor_page Layout */
/* ------------------------------------------------------ */
/* | 0 | TriggerState (4 bytes) | Rsvd1 (4 bytes) | */
/* | 8 | TriggerGroup[0] | */
/* | 10 | TriggerGroup[1] | */
/* | 18 | TriggerGroup[2] | */
/* | 20 | TriggerGroup[3] | */
/* | 28 | Rsvd2[0] | */
/* | 30 | Rsvd2[1] | */
/* | 38 | Rsvd2[2] | */
/* | 40 | NextCheckTime[0][0] | NextCheckTime[0][1] | */
/* | ... | */
/* | 240 | Latency[0][0..3] | */
/* | 340 | Rsvz3[0] | */
/* | 440 | Parameter[0][0] | */
/* | 448 | Parameter[0][1] | */
/* | ... | */
/* | 840 | Rsvd4[0] | */
/* ------------------------------------------------------ */
struct hv_monitor_page {
union hv_monitor_trigger_state trigger_state;
u32 rsvdz1;
union hv_monitor_trigger_group trigger_group[4];
u64 rsvdz2[3];
s32 next_checktime[4][32];
u16 latency[4][32];
u64 rsvdz3[32];
struct hv_monitor_parameter parameter[4][32];
u8 rsvdz4[1984];
};
#define HV_HYPERCALL_PARAM_ALIGN sizeof(u64)
/* Definition of the hv_post_message hypercall input structure. */
struct hv_input_post_message {
union hv_connection_id connectionid;
u32 reserved;
u32 message_type;
u32 payload_size;
u64 payload[HV_MESSAGE_PAYLOAD_QWORD_COUNT];
};
enum {
VMBUS_MESSAGE_CONNECTION_ID = 1,
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VMBUS_MESSAGE_CONNECTION_ID_4 = 4,
VMBUS_MESSAGE_PORT_ID = 1,
VMBUS_EVENT_CONNECTION_ID = 2,
VMBUS_EVENT_PORT_ID = 2,
VMBUS_MONITOR_CONNECTION_ID = 3,
VMBUS_MONITOR_PORT_ID = 3,
VMBUS_MESSAGE_SINT = 2,
};
/*
* Per cpu state for channel handling
*/
struct hv_per_cpu_context {
void *synic_message_page;
void *synic_event_page;
/*
* buffer to post messages to the host.
*/
void *post_msg_page;
/*
* Starting with win8, we can take channel interrupts on any CPU;
* we will manage the tasklet that handles events messages on a per CPU
* basis.
*/
struct tasklet_struct msg_dpc;
};
struct hv_context {
/* We only support running on top of Hyper-V
* So at this point this really can only contain the Hyper-V ID
*/
u64 guestid;
struct hv_per_cpu_context __percpu *cpu_context;
/*
* To manage allocations in a NUMA node.
* Array indexed by numa node ID.
*/
struct cpumask *hv_numa_map;
};
extern struct hv_context hv_context;
/* Hv Interface */
extern int hv_init(void);
extern int hv_post_message(union hv_connection_id connection_id,
enum hv_message_type message_type,
void *payload, size_t payload_size);
extern int hv_synic_alloc(void);
extern void hv_synic_free(void);
extern void hv_synic_enable_regs(unsigned int cpu);
extern int hv_synic_init(unsigned int cpu);
extern void hv_synic_disable_regs(unsigned int cpu);
extern int hv_synic_cleanup(unsigned int cpu);
/* Interface */
void hv_ringbuffer_pre_init(struct vmbus_channel *channel);
int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
struct page *pages, u32 pagecnt);
void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info);
int hv_ringbuffer_write(struct vmbus_channel *channel,
const struct kvec *kv_list, u32 kv_count);
int hv_ringbuffer_read(struct vmbus_channel *channel,
void *buffer, u32 buflen, u32 *buffer_actual_len,
u64 *requestid, bool raw);
/*
* The Maximum number of channels (16348) is determined by the size of the
* interrupt page, which is HV_HYP_PAGE_SIZE. 1/2 of HV_HYP_PAGE_SIZE is to
* send endpoint interrupts, and the other is to receive endpoint interrupts.
*/
#define MAX_NUM_CHANNELS ((HV_HYP_PAGE_SIZE >> 1) << 3)
/* The value here must be in multiple of 32 */
/* TODO: Need to make this configurable */
#define MAX_NUM_CHANNELS_SUPPORTED 256
Drivers: hv: vmbus: Replace the per-CPU channel lists with a global array of channels When Hyper-V sends an interrupt to the guest, the guest has to figure out which channel the interrupt is associated with. Hyper-V sets a bit in a memory page that is shared with the guest, indicating a particular "relid" that the interrupt is associated with. The current Linux code then uses a set of per-CPU linked lists to map a given "relid" to a pointer to a channel structure. This design introduces a synchronization problem if the CPU that Hyper-V will interrupt for a certain channel is changed. If the interrupt comes on the "old CPU" and the channel was already moved to the per-CPU list of the "new CPU", then the relid -> channel mapping will fail and the interrupt is dropped. Similarly, if the interrupt comes on the new CPU but the channel was not moved to the per-CPU list of the new CPU, then the mapping will fail and the interrupt is dropped. Relids are integers ranging from 0 to 2047. The mapping from relids to channel structures can be done by setting up an array with 2048 entries, each entry being a pointer to a channel structure (hence total size ~16K bytes, which is not a problem). The array is global, so there are no per-CPU linked lists to update. The array can be searched and updated by loading from/storing to the array at the specified index. With no per-CPU data structures, the above mentioned synchronization problem is avoided and the relid2channel() function gets simpler. Suggested-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com> Link: https://lore.kernel.org/r/20200406001514.19876-4-parri.andrea@gmail.com Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org>
2020-04-06 00:15:06 +00:00
#define MAX_CHANNEL_RELIDS \
max(MAX_NUM_CHANNELS_SUPPORTED, HV_EVENT_FLAGS_COUNT)
enum vmbus_connect_state {
DISCONNECTED,
CONNECTING,
CONNECTED,
DISCONNECTING
};
#define MAX_SIZE_CHANNEL_MESSAGE HV_MESSAGE_PAYLOAD_BYTE_COUNT
/*
* The CPU that Hyper-V will interrupt for VMBUS messages, such as
* CHANNELMSG_OFFERCHANNEL and CHANNELMSG_RESCIND_CHANNELOFFER.
*/
#define VMBUS_CONNECT_CPU 0
struct vmbus_connection {
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u32 msg_conn_id;
atomic_t offer_in_progress;
enum vmbus_connect_state conn_state;
atomic_t next_gpadl_handle;
struct completion unload_event;
/*
* Represents channel interrupts. Each bit position represents a
* channel. When a channel sends an interrupt via VMBUS, it finds its
* bit in the sendInterruptPage, set it and calls Hv to generate a port
* event. The other end receives the port event and parse the
* recvInterruptPage to see which bit is set
*/
void *int_page;
void *send_int_page;
void *recv_int_page;
/*
* 2 pages - 1st page for parent->child notification and 2nd
* is child->parent notification
*/
struct hv_monitor_page *monitor_pages[2];
struct list_head chn_msg_list;
spinlock_t channelmsg_lock;
/* List of channels */
struct list_head chn_list;
struct mutex channel_mutex;
Drivers: hv: vmbus: Replace the per-CPU channel lists with a global array of channels When Hyper-V sends an interrupt to the guest, the guest has to figure out which channel the interrupt is associated with. Hyper-V sets a bit in a memory page that is shared with the guest, indicating a particular "relid" that the interrupt is associated with. The current Linux code then uses a set of per-CPU linked lists to map a given "relid" to a pointer to a channel structure. This design introduces a synchronization problem if the CPU that Hyper-V will interrupt for a certain channel is changed. If the interrupt comes on the "old CPU" and the channel was already moved to the per-CPU list of the "new CPU", then the relid -> channel mapping will fail and the interrupt is dropped. Similarly, if the interrupt comes on the new CPU but the channel was not moved to the per-CPU list of the new CPU, then the mapping will fail and the interrupt is dropped. Relids are integers ranging from 0 to 2047. The mapping from relids to channel structures can be done by setting up an array with 2048 entries, each entry being a pointer to a channel structure (hence total size ~16K bytes, which is not a problem). The array is global, so there are no per-CPU linked lists to update. The array can be searched and updated by loading from/storing to the array at the specified index. With no per-CPU data structures, the above mentioned synchronization problem is avoided and the relid2channel() function gets simpler. Suggested-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com> Link: https://lore.kernel.org/r/20200406001514.19876-4-parri.andrea@gmail.com Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org>
2020-04-06 00:15:06 +00:00
/* Array of channels */
struct vmbus_channel **channels;
Drivers: hv: vmbus: Offload the handling of channels to two workqueues vmbus_process_offer() mustn't call channel->sc_creation_callback() directly for sub-channels, because sc_creation_callback() -> vmbus_open() may never get the host's response to the OPEN_CHANNEL message (the host may rescind a channel at any time, e.g. in the case of hot removing a NIC), and vmbus_onoffer_rescind() may not wake up the vmbus_open() as it's blocked due to a non-zero vmbus_connection.offer_in_progress, and finally we have a deadlock. The above is also true for primary channels, if the related device drivers use sync probing mode by default. And, usually the handling of primary channels and sub-channels can depend on each other, so we should offload them to different workqueues to avoid possible deadlock, e.g. in sync-probing mode, NIC1's netvsc_subchan_work() can race with NIC2's netvsc_probe() -> rtnl_lock(), and causes deadlock: the former gets the rtnl_lock and waits for all the sub-channels to appear, but the latter can't get the rtnl_lock and this blocks the handling of sub-channels. The patch can fix the multiple-NIC deadlock described above for v3.x kernels (e.g. RHEL 7.x) which don't support async-probing of devices, and v4.4, v4.9, v4.14 and v4.18 which support async-probing but don't enable async-probing for Hyper-V drivers (yet). The patch can also fix the hang issue in sub-channel's handling described above for all versions of kernels, including v4.19 and v4.20-rc4. So actually the patch should be applied to all the existing kernels, not only the kernels that have 8195b1396ec8. Fixes: 8195b1396ec8 ("hv_netvsc: fix deadlock on hotplug") Cc: stable@vger.kernel.org Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.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>
2018-12-03 00:54:35 +00:00
/*
* An offer message is handled first on the work_queue, and then
* is further handled on handle_primary_chan_wq or
* handle_sub_chan_wq.
*/
struct workqueue_struct *work_queue;
Drivers: hv: vmbus: Offload the handling of channels to two workqueues vmbus_process_offer() mustn't call channel->sc_creation_callback() directly for sub-channels, because sc_creation_callback() -> vmbus_open() may never get the host's response to the OPEN_CHANNEL message (the host may rescind a channel at any time, e.g. in the case of hot removing a NIC), and vmbus_onoffer_rescind() may not wake up the vmbus_open() as it's blocked due to a non-zero vmbus_connection.offer_in_progress, and finally we have a deadlock. The above is also true for primary channels, if the related device drivers use sync probing mode by default. And, usually the handling of primary channels and sub-channels can depend on each other, so we should offload them to different workqueues to avoid possible deadlock, e.g. in sync-probing mode, NIC1's netvsc_subchan_work() can race with NIC2's netvsc_probe() -> rtnl_lock(), and causes deadlock: the former gets the rtnl_lock and waits for all the sub-channels to appear, but the latter can't get the rtnl_lock and this blocks the handling of sub-channels. The patch can fix the multiple-NIC deadlock described above for v3.x kernels (e.g. RHEL 7.x) which don't support async-probing of devices, and v4.4, v4.9, v4.14 and v4.18 which support async-probing but don't enable async-probing for Hyper-V drivers (yet). The patch can also fix the hang issue in sub-channel's handling described above for all versions of kernels, including v4.19 and v4.20-rc4. So actually the patch should be applied to all the existing kernels, not only the kernels that have 8195b1396ec8. Fixes: 8195b1396ec8 ("hv_netvsc: fix deadlock on hotplug") Cc: stable@vger.kernel.org Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.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>
2018-12-03 00:54:35 +00:00
struct workqueue_struct *handle_primary_chan_wq;
struct workqueue_struct *handle_sub_chan_wq;
/*
* The number of sub-channels and hv_sock channels that should be
* cleaned up upon suspend: sub-channels will be re-created upon
* resume, and hv_sock channels should not survive suspend.
*/
atomic_t nr_chan_close_on_suspend;
/*
* vmbus_bus_suspend() waits for "nr_chan_close_on_suspend" to
* drop to zero.
*/
struct completion ready_for_suspend_event;
/*
* The number of primary channels that should be "fixed up"
* upon resume: these channels are re-offered upon resume, and some
* fields of the channel offers (i.e. child_relid and connection_id)
* can change, so the old offermsg must be fixed up, before the resume
* callbacks of the VSC drivers start to further touch the channels.
*/
atomic_t nr_chan_fixup_on_resume;
/*
* vmbus_bus_resume() waits for "nr_chan_fixup_on_resume" to
* drop to zero.
*/
struct completion ready_for_resume_event;
};
struct vmbus_msginfo {
/* Bookkeeping stuff */
struct list_head msglist_entry;
/* The message itself */
unsigned char msg[];
};
extern struct vmbus_connection vmbus_connection;
int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version);
static inline void vmbus_send_interrupt(u32 relid)
{
sync_set_bit(relid, vmbus_connection.send_int_page);
}
enum vmbus_message_handler_type {
/* The related handler can sleep. */
VMHT_BLOCKING = 0,
/* The related handler must NOT sleep. */
VMHT_NON_BLOCKING = 1,
};
struct vmbus_channel_message_table_entry {
enum vmbus_channel_message_type message_type;
enum vmbus_message_handler_type handler_type;
void (*message_handler)(struct vmbus_channel_message_header *msg);
u32 min_payload_len;
};
extern const struct vmbus_channel_message_table_entry
channel_message_table[CHANNELMSG_COUNT];
/* General vmbus interface */
struct hv_device *vmbus_device_create(const guid_t *type,
const guid_t *instance,
struct vmbus_channel *channel);
int vmbus_device_register(struct hv_device *child_device_obj);
void vmbus_device_unregister(struct hv_device *device_obj);
int vmbus_add_channel_kobj(struct hv_device *device_obj,
struct vmbus_channel *channel);
Drivers: hv: vmbus: Expose monitor data only when monitor pages are used There are two methods for signaling the host: the monitor page mechanism and hypercalls. The monitor page mechanism is used by performance critical channels (storage, networking, etc.) because it provides improved throughput. However, latency is increased. Monitor pages are allocated to these channels. Monitor pages are not allocated to channels that do not use the monitor page mechanism. Therefore, these channels do not have a valid monitor id or valid monitor page data. In these cases, some of the "_show" functions return incorrect data. They return an invalid monitor id and data that is beyond the bounds of the hv_monitor_page array fields. The "channel->offermsg.monitor_allocated" value can be used to determine whether monitor pages have been allocated to a channel. Add "is_visible()" callback functions for the device-level and channel-level attribute groups. These functions will hide the monitor sysfs files when the monitor mechanism is not used. Remove ".default_attributes" from "vmbus_chan_attrs" and create a channel-level attribute group. These changes allow the new "is_visible()" callback function to be applied to the channel-level attributes. Call "sysfs_create_group()" in "vmbus_add_channel_kobj()" to create the channel's sysfs files. Add a new function, “vmbus_remove_channel_attr_group()”, and call it in "free_channel()" to remove the channel's sysfs files when the channel is closed. Signed-off-by: Kimberly Brown <kimbrownkd@gmail.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-19 04:04:01 +00:00
void vmbus_remove_channel_attr_group(struct vmbus_channel *channel);
Drivers: hv: vmbus: Replace the per-CPU channel lists with a global array of channels When Hyper-V sends an interrupt to the guest, the guest has to figure out which channel the interrupt is associated with. Hyper-V sets a bit in a memory page that is shared with the guest, indicating a particular "relid" that the interrupt is associated with. The current Linux code then uses a set of per-CPU linked lists to map a given "relid" to a pointer to a channel structure. This design introduces a synchronization problem if the CPU that Hyper-V will interrupt for a certain channel is changed. If the interrupt comes on the "old CPU" and the channel was already moved to the per-CPU list of the "new CPU", then the relid -> channel mapping will fail and the interrupt is dropped. Similarly, if the interrupt comes on the new CPU but the channel was not moved to the per-CPU list of the new CPU, then the mapping will fail and the interrupt is dropped. Relids are integers ranging from 0 to 2047. The mapping from relids to channel structures can be done by setting up an array with 2048 entries, each entry being a pointer to a channel structure (hence total size ~16K bytes, which is not a problem). The array is global, so there are no per-CPU linked lists to update. The array can be searched and updated by loading from/storing to the array at the specified index. With no per-CPU data structures, the above mentioned synchronization problem is avoided and the relid2channel() function gets simpler. Suggested-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com> Link: https://lore.kernel.org/r/20200406001514.19876-4-parri.andrea@gmail.com Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Wei Liu <wei.liu@kernel.org>
2020-04-06 00:15:06 +00:00
void vmbus_channel_map_relid(struct vmbus_channel *channel);
void vmbus_channel_unmap_relid(struct vmbus_channel *channel);
struct vmbus_channel *relid2channel(u32 relid);
void vmbus_free_channels(void);
/* Connection interface */
int vmbus_connect(void);
Drivers: hv: vmbus: teardown hv_vmbus_con workqueue and vmbus_connection pages on shutdown We need to destroy hv_vmbus_con on module shutdown, otherwise the following crash is sometimes observed: [ 76.569845] hv_vmbus: Hyper-V Host Build:9600-6.3-17-0.17039; Vmbus version:3.0 [ 82.598859] BUG: unable to handle kernel paging request at ffffffffa0003480 [ 82.599287] IP: [<ffffffffa0003480>] 0xffffffffa0003480 [ 82.599287] PGD 1f34067 PUD 1f35063 PMD 3f72d067 PTE 0 [ 82.599287] Oops: 0010 [#1] SMP [ 82.599287] Modules linked in: [last unloaded: hv_vmbus] [ 82.599287] CPU: 0 PID: 26 Comm: kworker/0:1 Not tainted 3.19.0-rc5_bug923184+ #488 [ 82.599287] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v1.0 11/26/2012 [ 82.599287] Workqueue: hv_vmbus_con 0xffffffffa0003480 [ 82.599287] task: ffff88007b6ddfa0 ti: ffff88007f8f8000 task.ti: ffff88007f8f8000 [ 82.599287] RIP: 0010:[<ffffffffa0003480>] [<ffffffffa0003480>] 0xffffffffa0003480 [ 82.599287] RSP: 0018:ffff88007f8fbe00 EFLAGS: 00010202 ... To avoid memory leaks we need to free monitor_pages and int_page for vmbus_connection. Implement vmbus_disconnect() function by separating cleanup path from vmbus_connect(). As we use hv_vmbus_con to release channels (see free_channel() in channel_mgmt.c) we need to make sure the work was done before we remove the queue, do that with drain_workqueue(). We also need to avoid handling messages which can (potentially) create new channels, so set vmbus_connection.conn_state = DISCONNECTED at the very beginning of vmbus_exit() and check for that in vmbus_onmessage_work(). 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>
2015-02-27 19:25:54 +00:00
void vmbus_disconnect(void);
int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep);
void vmbus_on_event(unsigned long data);
void vmbus_on_msg_dpc(unsigned long data);
int hv_kvp_init(struct hv_util_service *srv);
void hv_kvp_deinit(void);
int hv_kvp_pre_suspend(void);
int hv_kvp_pre_resume(void);
void hv_kvp_onchannelcallback(void *context);
int hv_vss_init(struct hv_util_service *srv);
void hv_vss_deinit(void);
int hv_vss_pre_suspend(void);
int hv_vss_pre_resume(void);
void hv_vss_onchannelcallback(void *context);
int hv_fcopy_init(struct hv_util_service *srv);
void hv_fcopy_deinit(void);
int hv_fcopy_pre_suspend(void);
int hv_fcopy_pre_resume(void);
void hv_fcopy_onchannelcallback(void *context);
void vmbus_initiate_unload(bool crash);
static inline void hv_poll_channel(struct vmbus_channel *channel,
void (*cb)(void *))
{
if (!channel)
return;
cb(channel);
}
enum hvutil_device_state {
HVUTIL_DEVICE_INIT = 0, /* driver is loaded, waiting for userspace */
HVUTIL_READY, /* userspace is registered */
HVUTIL_HOSTMSG_RECEIVED, /* message from the host was received */
HVUTIL_USERSPACE_REQ, /* request to userspace was sent */
HVUTIL_USERSPACE_RECV, /* reply from userspace was received */
HVUTIL_DEVICE_DYING, /* driver unload is in progress */
};
enum delay {
INTERRUPT_DELAY = 0,
MESSAGE_DELAY = 1,
};
Drivers: hv: vmbus: Resolve more races involving init_vp_index() init_vp_index() uses the (per-node) hv_numa_map[] masks to record the CPUs allocated for channel interrupts at a given time, and distribute the performance-critical channels across the available CPUs: in part., the mask of "candidate" target CPUs in a given NUMA node, for a newly offered channel, is determined by XOR-ing the node's CPU mask and the node's hv_numa_map. This operation/mechanism assumes that no offline CPUs is set in the hv_numa_map mask, an assumption that does not hold since such mask is currently not updated when a channel is removed or assigned to a different CPU. To address the issues described above, this adds hooks in the channel removal path (hv_process_channel_removal()) and in target_cpu_store() in order to clear, resp. to update, the hv_numa_map[] masks as needed. This also adds a (missed) update of the masks in init_vp_index() (cf., e.g., the memory-allocation failure path in this function). Like in the case of init_vp_index(), such hooks require to determine if the given channel is performance critical. init_vp_index() does this by parsing the channel's offer, it can not rely on the device data structure (device_obj) to retrieve such information because the device data structure has not been allocated/linked with the channel by the time that init_vp_index() executes. A similar situation may hold in hv_is_alloced_cpu() (defined below); the adopted approach is to "cache" the device type of the channel, as computed by parsing the channel's offer, in the channel structure itself. Fixes: 7527810573436f ("Drivers: hv: vmbus: Introduce the CHANNELMSG_MODIFYCHANNEL message type") Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com> Reviewed-by: Michael Kelley <mikelley@microsoft.com> Link: https://lore.kernel.org/r/20200522171901.204127-3-parri.andrea@gmail.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
2020-05-22 17:19:01 +00:00
extern const struct vmbus_device vmbus_devs[];
static inline bool hv_is_perf_channel(struct vmbus_channel *channel)
{
return vmbus_devs[channel->device_id].perf_device;
}
static inline bool hv_is_alloced_cpu(unsigned int cpu)
{
struct vmbus_channel *channel, *sc;
lockdep_assert_held(&vmbus_connection.channel_mutex);
/*
* List additions/deletions as well as updates of the target CPUs are
* protected by channel_mutex.
*/
list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
if (!hv_is_perf_channel(channel))
continue;
if (channel->target_cpu == cpu)
return true;
list_for_each_entry(sc, &channel->sc_list, sc_list) {
if (sc->target_cpu == cpu)
return true;
}
}
return false;
}
static inline void hv_set_alloced_cpu(unsigned int cpu)
{
cpumask_set_cpu(cpu, &hv_context.hv_numa_map[cpu_to_node(cpu)]);
}
static inline void hv_clear_alloced_cpu(unsigned int cpu)
{
if (hv_is_alloced_cpu(cpu))
return;
cpumask_clear_cpu(cpu, &hv_context.hv_numa_map[cpu_to_node(cpu)]);
}
static inline void hv_update_alloced_cpus(unsigned int old_cpu,
unsigned int new_cpu)
{
hv_set_alloced_cpu(new_cpu);
hv_clear_alloced_cpu(old_cpu);
}
#ifdef CONFIG_HYPERV_TESTING
int hv_debug_add_dev_dir(struct hv_device *dev);
void hv_debug_rm_dev_dir(struct hv_device *dev);
void hv_debug_rm_all_dir(void);
int hv_debug_init(void);
void hv_debug_delay_test(struct vmbus_channel *channel, enum delay delay_type);
#else /* CONFIG_HYPERV_TESTING */
static inline void hv_debug_rm_dev_dir(struct hv_device *dev) {};
static inline void hv_debug_rm_all_dir(void) {};
static inline void hv_debug_delay_test(struct vmbus_channel *channel,
enum delay delay_type) {};
static inline int hv_debug_init(void)
{
return -1;
}
static inline int hv_debug_add_dev_dir(struct hv_device *dev)
{
return -1;
}
#endif /* CONFIG_HYPERV_TESTING */
#endif /* _HYPERV_VMBUS_H */