Re: [Qemu-devel] [PATCH v1] vhost-user: fix not send all hugepage files to vhost-user

[Linhaifeng <haifeng.lin@huawei.com>]

On 2015/1/29 18:51, Michael S. Tsirkin wrote:
> On Thu, Jan 29, 2015 at 11:58:08AM +0800, Linhaifeng wrote:
>> Hi,Michael S.Tsirkin
>>
>> The vhost-user device will not work if there are two numa nodes in VM.
>>
>> Should we fix this bug or ignore it ?
> 
> I suggest we fix this bug.
> I saw that you responded to self so I assume you will
> send v2 with the modification you listed.
> Did I get it right?
> 
> Also, pls Cc qemu-stable on bugfixes.
> 
> Thanks!
> 

Hi,Michael S.Tsirkin

Yes,in v2 i want to write vhost-user-test.c to show how to mmap and how to calculate address
then you and other one can review it.But i don't know how to compile and run the test.
Is there any document to show it?

BTW.I know you wrote virtio_net driver and vhost. Is there any document to introduce the principle
or how the virtio and vhost work?

>> On 2014/12/18 13:06, Linhaifeng wrote:
>>>
>>>
>>> On 2014/12/17 14:02, haifeng.lin@huawei.com wrote:
>>>> From: linhaifeng <haifeng.lin@huawei.com>
>>>>
>>>> If we create VM with two or more numa nodes qemu will create two
>>>> or more hugepage files but qemu only send one hugepage file fd
>>>> to vhost-user when VM's memory size is 2G and with two numa nodes.
>>>>
>>>> Signed-off-by: linhaifeng <haifeng.lin@huawei.com>
>>>> ---
>>>>  hw/virtio/vhost-user.c      | 78 ++++++++++++++++++++++++++++++---------------
>>>>  hw/virtio/vhost.c           | 13 ++++++++
>>>>  linux-headers/linux/vhost.h |  7 ++++
>>>>  3 files changed, 73 insertions(+), 25 deletions(-)
>>>>
>>>> diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
>>>> index aefe0bb..439cbba 100644
>>>> --- a/hw/virtio/vhost-user.c
>>>> +++ b/hw/virtio/vhost-user.c
>>>> @@ -24,6 +24,10 @@
>>>>  #include <linux/vhost.h>
>>>>  
>>>>  #define VHOST_MEMORY_MAX_NREGIONS    8
>>>> +/* FIXME: same as the max number of numa node?*/
>>>> +#define HUGEPAGE_MAX_FILES           8
>>>> +
>>>> +#define RAM_SHARED     (1 << 1)
>>>>  
>>>>  typedef enum VhostUserRequest {
>>>>      VHOST_USER_NONE = 0,
>>>> @@ -41,14 +45,15 @@ typedef enum VhostUserRequest {
>>>>      VHOST_USER_SET_VRING_KICK = 12,
>>>>      VHOST_USER_SET_VRING_CALL = 13,
>>>>      VHOST_USER_SET_VRING_ERR = 14,
>>>> -    VHOST_USER_MAX
>>>> +    VHOST_USER_MMAP_HUGEPAGE_FILE = 15,
>>>> +    VHOST_USER_UNMAP_HUGEPAGE_FILE = 16,
>>>> +    VHOST_USER_MAX,
>>>>  } VhostUserRequest;
>>>>  
>>>>  typedef struct VhostUserMemoryRegion {
>>>>      uint64_t guest_phys_addr;
>>>>      uint64_t memory_size;
>>>>      uint64_t userspace_addr;
>>>> -    uint64_t mmap_offset;
>>>>  } VhostUserMemoryRegion;
>>>>  
>>>>  typedef struct VhostUserMemory {
>>>> @@ -57,6 +62,16 @@ typedef struct VhostUserMemory {
>>>>      VhostUserMemoryRegion regions[VHOST_MEMORY_MAX_NREGIONS];
>>>>  } VhostUserMemory;
>>>>  
>>>> +typedef struct HugepageMemoryInfo {
>>>> +    uint64_t base_addr;
>>>> +    uint64_t size;
>>>> +}HugeMemInfo;
>>>> +
>>>> +typedef struct HugepageInfo {
>>>> +    uint32_t num;
>>>> +    HugeMemInfo files[HUGEPAGE_MAX_FILES];
>>>> +}HugepageInfo;
>>>> +
>>>>  typedef struct VhostUserMsg {
>>>>      VhostUserRequest request;
>>>>  
>>>> @@ -71,6 +86,7 @@ typedef struct VhostUserMsg {
>>>>          struct vhost_vring_state state;
>>>>          struct vhost_vring_addr addr;
>>>>          VhostUserMemory memory;
>>>> +        HugepageInfo huge_info;
>>>>      };
>>>>  } QEMU_PACKED VhostUserMsg;
>>>>  
>>>> @@ -104,7 +120,9 @@ static unsigned long int ioctl_to_vhost_user_request[VHOST_USER_MAX] = {
>>>>      VHOST_GET_VRING_BASE,   /* VHOST_USER_GET_VRING_BASE */
>>>>      VHOST_SET_VRING_KICK,   /* VHOST_USER_SET_VRING_KICK */
>>>>      VHOST_SET_VRING_CALL,   /* VHOST_USER_SET_VRING_CALL */
>>>> -    VHOST_SET_VRING_ERR     /* VHOST_USER_SET_VRING_ERR */
>>>> +    VHOST_SET_VRING_ERR,    /* VHOST_USER_SET_VRING_ERR */
>>>> +    VHOST_MMAP_HUGEPAGE_FILE,  /* VHOST_USER_MMAP_HUGEPAGE_FILE */
>>>> +    VHOST_UNMAP_HUGEPAGE_FILE, /* VHOST_USER_UNMAP_HUGEPAGE_FILE */
>>>>  };
>>>>  
>>>>  static VhostUserRequest vhost_user_request_translate(unsigned long int request)
>>>> @@ -190,6 +208,7 @@ static int vhost_user_call(struct vhost_dev *dev, unsigned long int request,
>>>>      int fds[VHOST_MEMORY_MAX_NREGIONS];
>>>>      int i, fd;
>>>>      size_t fd_num = 0;
>>>> +    RAMBlock *block;
>>>>  
>>>>      assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
>>>>  
>>>> @@ -213,37 +232,46 @@ static int vhost_user_call(struct vhost_dev *dev, unsigned long int request,
>>>>      case VHOST_RESET_OWNER:
>>>>          break;
>>>>  
>>>> -    case VHOST_SET_MEM_TABLE:
>>>> -        for (i = 0; i < dev->mem->nregions; ++i) {
>>>> -            struct vhost_memory_region *reg = dev->mem->regions + i;
>>>> -            ram_addr_t ram_addr;
>>>> +    case VHOST_MMAP_HUGEPAGE_FILE:
>>>> +        qemu_mutex_lock_ramlist();
>>>>  
>>>> -            assert((uintptr_t)reg->userspace_addr == reg->userspace_addr);
>>>> -            qemu_ram_addr_from_host((void *)(uintptr_t)reg->userspace_addr, &ram_addr);
>>>> -            fd = qemu_get_ram_fd(ram_addr);
>>>> -            if (fd > 0) {
>>>> -                msg.memory.regions[fd_num].userspace_addr = reg->userspace_addr;
>>>> -                msg.memory.regions[fd_num].memory_size  = reg->memory_size;
>>>> -                msg.memory.regions[fd_num].guest_phys_addr = reg->guest_phys_addr;
>>>> -                msg.memory.regions[fd_num].mmap_offset = reg->userspace_addr -
>>>> -                    (uintptr_t) qemu_get_ram_block_host_ptr(ram_addr);
>>>> -                assert(fd_num < VHOST_MEMORY_MAX_NREGIONS);
>>>> -                fds[fd_num++] = fd;
>>>> +        /* Get hugepage file informations */
>>>> +        QTAILQ_FOREACH(block, &ram_list.blocks, next) {
>>>> +            if (block->flags & RAM_SHARED && block->fd > 0) {
>>>> +                msg.huge_info.files[fd_num].size = block->length;
>>>> +                msg.huge_info.files[fd_num].base_addr = block->host;
>>>> +                fds[fd_num++] = block->fd;
>>>>              }
>>>>          }
>>>> +        msg.huge_info.num = fd_num;
>>>>  
>>>> -        msg.memory.nregions = fd_num;
>>>> +        /* Calculate msg size */
>>>> +        msg.size = sizeof(m.huge_info.num);
>>>> +        msg.size += fd_num * sizeof(HugeMemInfo);
>>>> +        
>>>> +        qemu_mutex_unlock_ramlist();        
>>>> +        break;
>>>>  
>>>> -        if (!fd_num) {
>>>> -            error_report("Failed initializing vhost-user memory map\n"
>>>> -                    "consider using -object memory-backend-file share=on\n");
>>>> -            return -1;
>>>> +    case VHOST_UNMAP_HUGEPAGE_FILE:
>>>> +        /* Tell vhost-user to unmap all hugepage files. */
>>>> +        break;
>>>> +
>>>> +    case VHOST_SET_MEM_TABLE:
>>>> +        for (i = 0; i < dev->mem->nregions; i++) {
>>>> +            struct vhost_memory_region *reg = dev->mem->regions + i;
>>>> +
>>>> +            assert((uintptr_t)reg->userspace_addr == reg->userspace_addr);
>>>> +
>>>> +            msg.memory.regions[i].userspace_addr = reg->userspace_addr;
>>>> +            msg.memory.regions[i].memory_size  = reg->memory_size;
>>>> +            msg.memory.regions[i].guest_phys_addr = reg->guest_phys_addr;
>>>> +            assert(fd_num < VHOST_MEMORY_MAX_NREGIONS);
>>>>          }
>>>>  
>>>> +        msg.memory.nregions = i;
>>>>          msg.size = sizeof(m.memory.nregions);
>>>>          msg.size += sizeof(m.memory.padding);
>>>> -        msg.size += fd_num * sizeof(VhostUserMemoryRegion);
>>>> -
>>>> +        msg.size += i * sizeof(VhostUserMemoryRegion);
>>>>          break;
>>>>  
>>>>      case VHOST_SET_LOG_FD:
>>>> diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
>>>> index 5a12861..b8eb341 100644
>>>> --- a/hw/virtio/vhost.c
>>>> +++ b/hw/virtio/vhost.c
>>>> @@ -1041,6 +1041,14 @@ int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev)
>>>>      if (r < 0) {
>>>>          goto fail_features;
>>>>      }
>>>> +    if (hdev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER) {
>>>> +        r = hdev->vhost_ops->vhost_call(hdev, VHOST_MMAP_HUGEPAGE_FILE, 
>>>> +            NULL);
>>>> +        if (r < 0) {
>>>> +            r = -errno;
>>>> +            goto fail_mem;
>>>> +        }    
>>>> +    }
>>>>      r = hdev->vhost_ops->vhost_call(hdev, VHOST_SET_MEM_TABLE, hdev->mem);
>>>>      if (r < 0) {
>>>>          r = -errno;
>>>> @@ -1101,5 +1109,10 @@ void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev)
>>>>      g_free(hdev->log);
>>>>      hdev->log = NULL;
>>>>      hdev->log_size = 0;
>>>> +
>>>> +    if (hdev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER) {
>>>> +        (void)hdev->vhost_ops->vhost_call(hdev, VHOST_MMAP_HUGEPAGE_FILE, 
>>>
>>> VHOST_MMAP_HUGEPAGE_FILE -> VHOST_UNMAP_HUGEPAGE_FILE
>>>
>>>> +            NULL);   
>>>> +    }    
>>>>  }
>>>>  
>>>> diff --git a/linux-headers/linux/vhost.h b/linux-headers/linux/vhost.h
>>>> index c656f61..bb72811 100644
>>>> --- a/linux-headers/linux/vhost.h
>>>> +++ b/linux-headers/linux/vhost.h
>>>> @@ -113,6 +113,13 @@ struct vhost_memory {
>>>>  /* Set eventfd to signal an error */
>>>>  #define VHOST_SET_VRING_ERR _IOW(VHOST_VIRTIO, 0x22, struct vhost_vring_file)
>>>>  
>>>> +/* Tell vhost-user to mmap hugepage file */
>>>> +#define VHOST_MMAP_HUGEPAGE_FILE _IOW(VHOST_VIRTIO, 0x23, int)
>>>> +/* Tell vhost-user to unmap hugepage file */
>>>> +#define VHOST_UNMAP_HUGEPAGE_FILE _IOW(VHOST_VIRTIO, 0x24, int)
>>>> +
>>>> +#define VHOST_THREAD_ID _IOR(VHOST_VIRTIO, 0x25, struct vhost_vring_thread)
>>>> +
>>>>  /* VHOST_NET specific defines */
>>>>  
>>>>  /* Attach virtio net ring to a raw socket, or tap device.
>>>>
>>>
>>
>> -- 
>> Regards,
>> Haifeng
> 
> .
> 

-- 
Regards,
Haifeng