Virtual machine systems

Patent metadata

Field	Value
Publication number	US-9747122-B2
Application number	US-201514688258-A
Country	US
Kind code	B2
Filing date	Apr 16, 2015
Priority date	Apr 16, 2015
Publication date	Aug 29, 2017
Grant date	Aug 29, 2017

Abstract

Methods, systems, and apparatus, including computer programs encoded on computer storage media, for memory requests by a virtual machine. One of the methods includes generating a plurality of doorbell pages for a plurality of virtual machines executing on a device, providing, to each of the plurality of virtual machines, access to a respective one of the plurality of doorbell pages that identifies a queue that stores requests from the respective virtual machine, receiving, from a particular one of the plurality of doorbell pages, a notification that the respective queue has a request from the respective virtual machine, and in response to receiving the notification that the respective queue has a request from the respective virtual machine, causing a processor to process the respective queue for the respective virtual machine.

First claim

What is claimed is:

1. A computer-implemented method comprising:
generating a plurality of doorbell pages for a plurality of virtual machines executing on a device by assigning a respective address to each of the plurality of doorbell pages;
providing, to each of the plurality of virtual machines, access to a respective one of the plurality of doorbell pages that identifies a ring buffer that stores requests from the respective virtual machine by providing, to each of the plurality of virtual machines, the respective address to the respective virtual machine;
receiving, from a particular one of the plurality of doorbell pages, a notification that the respective ring buffer has a request from the respective virtual machine; and
in response to receiving the notification that the respective ring buffer has a request from the respective virtual machine, causing a processor to process the respective ring buffer for the respective virtual machine.

2. The method of claim 1 , comprising:
continuing to execute the respective virtual machine while the processor processes the request.

3. The method of claim 1 , comprising:
receiving an update to the respective ring buffer prior to receiving the notification that the respective ring buffer has a request from the respective virtual machine.

4. The method of claim 1 , wherein causing a processor to process the respective ring buffer for the respective virtual machine comprises sending an interrupt to the processor.

5. The method of claim 1 , wherein:
generating the plurality of doorbell pages comprises generating a tracking structure and assigning a respective index from the tracking structure to each of the plurality of doorbell pages; and
providing, to each of the plurality of virtual machines, access to the respective one of the plurality of doorbell pages that identifies the ring buffer that stores requests from the respective virtual machine comprises providing, to each of the plurality of virtual machines, an address for the respective index to the respective virtual machine.

6. The method of claim 1 , wherein:
generating the plurality of doorbell pages comprises:
generating a page for each of the plurality of doorbell pages; and
assigning, for each of the plurality of doorbell pages, a non-zero offset at which the respective one of the plurality of doorbell pages resides within the respective page; and

providing, to each of the plurality of virtual machines, access to the respective one of the plurality of doorbell pages that identifies the ring buffer that stores requests from the respective virtual machine comprises providing, to each of the plurality of virtual machines, an address for the respective page and the non-zero offset to the respective virtual machine.

7. A computer-implemented method comprising:
generating a plurality of doorbell pages for a plurality of virtual machines executing on a device;
generating a bit vector that comprises, for each of the plurality of doorbell pages, a respective entry that uniquely corresponds to the doorbell page and uniquely identifies a queue that stores requests from the respective virtual machine and that is identified by the doorbell page;
providing, to each of the plurality of virtual machines, access to a respective one of the plurality of doorbell pages that identifies the queue that stores requests from the respective virtual machine;
receiving, from a particular one of the plurality of doorbell pages, a notification that the respective queue has a request from the respective virtual machine;
in response to receiving the notification that the respective queue has a request from the respective virtual machine, updating the respective entry in the bit vector that identifies the respective queue; and
in response to updating the respective entry in the bit vector that identifies the respective queue, causing a processor to process the respective queue for the respective virtual machine by providing the bit vector to the processor to cause the processor to process the respective queue for the respective virtual machine.

8. The method of claim 7 , wherein providing the bit vector to the processor to cause the processor to process the respective queue for the respective virtual machine comprises providing the bit vector to the processor to cause the processor to process multiple queues for the plurality of virtual machines.

9. The method of claim 7 , comprising:
continuing to execute the respective virtual machine while the processor processes the request.

10. The method of claim 7 , comprising:
receiving an update to the respective queue prior to receiving the notification that the respective queue has a request from the respective virtual machine.

11. A computer-implemented method comprising:
generating a first plurality of doorbell pages for a plurality of virtual machines executing on a device;
providing, to each of the plurality of virtual machines, access to a respective one of the first plurality of doorbell pages that identifies a first queue that stores first requests from the respective virtual machine, each of the first requests having a first type;
generating a second plurality of doorbell pages;
providing, to each of at least some of the plurality of virtual machines, access to a respective one of the second plurality of doorbell pages that identifies a second queue that stores second requests from the respective virtual machine, the first type of the first requests being different than a second type of the second requests;
receiving, from a particular one of the plurality of doorbell pages, a notification that the respective queue has a request from the respective virtual machine and that identifies a type of request; and
in response to receiving the notification that the respective queue has a request from the respective virtual machine:
determining that the type of request comprises the first type;
determining a particular processor assigned to service requests of the first type; and
causing the particular processor to process the respective queue for the respective virtual machine.

12. The method of claim 11 , comprising:
executing the plurality of virtual machines on a first processor of the device, wherein causing the particular processor to process the respective queue for the respective virtual machine comprises providing a message to a hypervisor executing on a second, different processor to cause the second, different processor to process the respective queue for the respective virtual machine.

13. The method of claim 12 , wherein providing the message to the hypervisor executing on the second, different processor comprises providing the message to the hypervisor executing on the second, different processor on a second device different from the device.

14. A system comprising:
a memory;
a data processing apparatus; and
a non-transitory computer readable storage medium in data communication with the data processing apparatus and storing instructions executable by the data processing apparatus and upon such execution cause the data processing apparatus to perform operations comprising:
storing a plurality of doorbell pages in the memory for a plurality of virtual machines executing on the system by assigning a respective address to each of the plurality of doorbell pages;
providing, to each of the plurality of virtual machines, access to a respective one of the plurality of doorbell pages that identifies a ring buffer that stores requests from the respective virtual machine by providing, to each of the plurality of virtual machines, the respective address to the respective virtual m

Assignees

• Google Inc

Inventors

• Serebrin Benjamin C

Classifications

• G06F9/45558 Primary

  Hypervisor-specific management and integration aspects · CPC title

• G06F9/546

  Message passing systems or structures, e.g. queues · CPC title

• G06F2009/4557

  Distribution of virtual machine instances; Migration and load balancing · CPC title

• G06F2209/548

  Queue · CPC title

• G06F2009/45583

  Memory management, e.g. access or allocation · CPC title