diff options
| author | Elena Ufimtseva | 2021-01-29 17:46:03 +0100 |
|---|---|---|
| committer | Stefan Hajnoczi | 2021-02-09 21:53:56 +0100 |
| commit | 639090d85057e7e8251e2509fa136f1a2384f131 (patch) | |
| tree | 84687e83b3ffcbd7cbbe2e62a8e5aecb2f3f1ceb /docs/system | |
| parent | multi-process: add the concept description to docs/devel/qemu-multiprocess (diff) | |
| download | qemu-639090d85057e7e8251e2509fa136f1a2384f131.tar.gz qemu-639090d85057e7e8251e2509fa136f1a2384f131.tar.xz qemu-639090d85057e7e8251e2509fa136f1a2384f131.zip | |
multi-process: add configure and usage information
Adds documentation explaining the command-line arguments needed
to use multi-process.
Signed-off-by: Elena Ufimtseva <elena.ufimtseva@oracle.com>
Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
Signed-off-by: John G Johnson <john.g.johnson@oracle.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 49f757a84e5dd6fae14b22544897d1124c5fdbad.1611938319.git.jag.raman@oracle.com
[Move orphan docs/multi-process.rst document into docs/system/ and add
it to index.rst to prevent Sphinx "document isn't included in any
toctree" error.
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Diffstat (limited to 'docs/system')
| -rw-r--r-- | docs/system/index.rst | 1 | ||||
| -rw-r--r-- | docs/system/multi-process.rst | 64 |
2 files changed, 65 insertions, 0 deletions
diff --git a/docs/system/index.rst b/docs/system/index.rst index d40f72c92b..625b494372 100644 --- a/docs/system/index.rst +++ b/docs/system/index.rst @@ -34,6 +34,7 @@ Contents: pr-manager targets security + multi-process deprecated removed-features build-platforms diff --git a/docs/system/multi-process.rst b/docs/system/multi-process.rst new file mode 100644 index 0000000000..46bb0cafc2 --- /dev/null +++ b/docs/system/multi-process.rst @@ -0,0 +1,64 @@ +Multi-process QEMU +================== + +This document describes how to configure and use multi-process qemu. +For the design document refer to docs/devel/qemu-multiprocess. + +1) Configuration +---------------- + +multi-process is enabled by default for targets that enable KVM + + +2) Usage +-------- + +Multi-process QEMU requires an orchestrator to launch. + +Following is a description of command-line used to launch mpqemu. + +* Orchestrator: + + - The Orchestrator creates a unix socketpair + + - It launches the remote process and passes one of the + sockets to it via command-line. + + - It then launches QEMU and specifies the other socket as an option + to the Proxy device object + +* Remote Process: + + - QEMU can enter remote process mode by using the "remote" machine + option. + + - The orchestrator creates a "remote-object" with details about + the device and the file descriptor for the device + + - The remaining options are no different from how one launches QEMU with + devices. + + - Example command-line for the remote process is as follows: + + /usr/bin/qemu-system-x86_64 \ + -machine x-remote \ + -device lsi53c895a,id=lsi0 \ + -drive id=drive_image2,file=/build/ol7-nvme-test-1.qcow2 \ + -device scsi-hd,id=drive2,drive=drive_image2,bus=lsi0.0,scsi-id=0 \ + -object x-remote-object,id=robj1,devid=lsi1,fd=4, + +* QEMU: + + - Since parts of the RAM are shared between QEMU & remote process, a + memory-backend-memfd is required to facilitate this, as follows: + + -object memory-backend-memfd,id=mem,size=2G + + - A "x-pci-proxy-dev" device is created for each of the PCI devices emulated + in the remote process. A "socket" sub-option specifies the other end of + unix channel created by orchestrator. The "id" sub-option must be specified + and should be the same as the "id" specified for the remote PCI device + + - Example commandline for QEMU is as follows: + + -device x-pci-proxy-dev,id=lsi0,socket=3 |