Methods and systems for maintaining state in a virtual machine when disconnected from graphics hardware

Patent metadata

Field	Value
Publication number	US-9514507-B2
Application number	US-201213687623-A
Country	US
Kind code	B2
Filing date	Nov 28, 2012
Priority date	Nov 29, 2011
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

The present disclosure is directed towards methods and systems for maintaining state in a virtual machine when disconnected from graphics hardware. The virtual machine is one of a plurality of virtual machines hosted by a hypervisor executing on a computing device. A control virtual machine may be hosted by a hypervisor executing on a computing device. The control virtual machine may store state information of a graphics processing unit (GPU) of the computing device. The GPU may render an image from a first virtual machine. The control virtual machine may remove, from the first virtual machine, access to the GPU. The control virtual machine may redirect the first virtual machine to a GPU emulation program. The GPU emulation program may render the image from the first virtual machine using at least a portion of the stored state information.

First claim

We claim:

1. In a computing device executing a hypervisor hosting a plurality of virtual machines, a method for maintaining state in one or more of the plurality of virtual machines when disconnected from graphics hardware, comprising:
(a) storing, by a control virtual machine hosted by the hypervisor executing on the computing device, state information of a graphics processing unit (GPU) of the computing device, the GPU rendering an image from a first virtual machine of the plurality of virtual machines;
(b) removing, from the first virtual machine, by the control virtual machine, access to the GPU;
(c) redirecting, by the control virtual machine, the first virtual machine to a GPU emulation program; and
(d) rendering, by the GPU emulation program, the image from the first virtual machine using at least a portion of the stored state information.

2. The method of claim 1 , wherein (a) comprises storing state information of the GPU to a buffer of the computing device.

3. The method of claim 1 , wherein (a) comprises copying at least a portion of a graphics stack of the GPU including a state of a graphics driver.

4. The method of claim 1 , further comprising determining, by the control virtual machine, that the GPU emulation program is available within the first virtual machine for execution.

5. The method of claim 1 , further comprising determining, by the control virtual machine, that the GPU emulation program is installed in the computing device.

6. The method of claim 1 , further comprising executing the GPU emulation program prior to removing access to the GPU.

7. The method of claim 1 , wherein the control virtual machine provides the first virtual machine with uninterrupted access to a graphics processing entity during the removal and redirection.

8. The method of claim 1 , wherein (c) comprises redirecting an application of the first virtual machine providing the image to the GPU emulation program.

9. The method of claim 1 , further comprising providing, by the control virtual machine, to a second virtual machine, access to the GPU responsive to the removal.

10. The method of claim 1 , further comprising restoring the stored state information to the GPU and redirecting the first virtual machine to the GPU.

11. In a computing device executing a hypervisor hosting a plurality of virtual machines, a system for maintaining state in one or more virtual machines of the plurality of virtual machines when disconnected from graphics hardware, comprising:
the hypervisor executing on the computing device and hosting a control virtual machine and a first virtual machine, wherein the control virtual machine is configured to:
store state information of a graphics processing unit (GPU) of the computing device, the GPU rendering an image from the first virtual machine;
remove, from the first virtual machine, access to the GPU; and redirecting the first virtual machine to a GPU emulation program,
wherein the GPU emulation program renders the image from the first virtual machine using at least a portion of the stored state information.

12. The system of claim 11 , wherein the control virtual machine stores state information of the GPU to a buffer of the computing device.

13. The system of claim 11 , wherein the control virtual machine copies at least a portion of a graphics stack of the GPU including a state of a graphics driver.

14. The system of claim 11 , wherein the control virtual machine determines that the GPU emulation program is available within the first virtual machine for execution.

15. The system of claim 11 , wherein the control virtual machine determines that the GPU emulation program is installed in the computing device.

16. The system of claim 11 , wherein the control virtual machine initiates execution of the GPU emulation program prior to removing access to the GPU.

17. The system of claim 11 , wherein the control virtual machine provides the first virtual machine with uninterrupted access to a graphics processing entity during the removal and redirection.

18. The system of claim 11 , wherein the control virtual machine redirects an application of the first virtual machine providing the image to the GPU emulation program.

19. The system of claim 11 , wherein the control virtual machine provides, to a second virtual machine, access to the GPU responsive to the removal.

20. The system of claim 11 , wherein the control virtual machine restores the stored state information to the GPU and redirects the first virtual machine to the GPU.

Assignees

• Citrix Systems Inc

Inventors

• Mckenzie James
• Guyader Jean

Classifications

• G06T1/20 Primary

  Processor architectures; Processor configuration, e.g. pipelining · CPC title

• G06F9/455

  Emulation; Interpretation; Software simulation, e.g. virtualisation or emulation of application or operating system execution engines · CPC title

• G06F9/45558

  Hypervisor-specific management and integration aspects · CPC title