Started with the presentation in October 2017 made by Marc-Andre (Red Hat) and Konrad Wilk (Oracle) [1], and continued by Jag's BoF at KVM Forum 2018, the multi-process project is now a prototype and presented in this patchset.
This first series enables the emulation of lsi53c895a in a separate process. We posted the Proof Of Concept patches [2] before the BoF session in 2018. Subsequently, we posted RFC v1 [3] & RFC v2 [4] of this series. Thanks to the v1 & v2 review, we were able to incorporate the feedback into our goals. In the summer of 2019, we participated in a conference with folks at RedHat, who provided us with feedback to improve the design of this project. We want to present version 3 of this series which incorporates the feedback we received for v2 & the enhancements suggested in the conference. Following are the improvements made in this series: - The command-line arguments are Orchestrator friendly. A new option named "-remote" carries the command-line of the emulation process. Added "rid" suboption to the "-device" option and moved "-drive" option to the emulation process's command-line. - Redesigned Monitor interface allows direct access to the remote process, thereby making it more scalable, maintainable & Orchestrator friendly. We also enabled more monitor commands for the remote process. - Enabled the remote process to run multiple LSI controllers - Redesigned the communication link to support multiple channels. MMIO transactions are carried out in a separate channel. - Fixed the bugs discovered during testing. Individual patches provide the details of these fixes. Following people contributed to this patchset: John G Johnson <john.g.john...@oracle.com> Jagannathan Raman <jag.ra...@oracle.com> Elena Ufimtseva <elena.ufimts...@oracle.com> Kanth Ghatraju <kanth.ghatr...@oracle.com> For full concept writeup about QEMU disaggregation refer to docs/devel/qemu-multiprocess.txt. Please refer to docs/qemu-multiprocess.txt for usage information. We are planning on making the following improvements in the future: - Live migration - Performance improvements - Libvirt support - Enforcement of security policies - blockdev support We welcome all your ideas, concerns, and questions for this patchset. Thank you! [1]: http://events17.linuxfoundation.org/sites/events/files/slides/KVM%20FORUM%20multi-process.pdf [1]: https://www.youtube.com/watch?v=Kq1-coHh7lg [2]: https://www.mail-archive.com/qemu-devel@nongnu.org/msg566538.html [3]: https://www.mail-archive.com/qemu-devel@nongnu.org/msg602285.html [4]: https://www.mail-archive.com/qemu-devel@nongnu.org/msg624877.html Elena Ufimtseva (20): multi-process: add a command line option for debug file multi-process: introduce proxy object mutli-process: build remote command line args multi-process: add support of device id to communication channel multi-process: modify BARs read/write to support dev_id multi-process: support dev id in config read/write multi-process: configure remote side devices multi-process: add qdev_proxy_add to create proxy devices multi-process: remote: add setup_devices and setup_drive msg processing multi-process: remote: use fd for socket from parent process multi-process: remote: add create_done condition multi-process: add processing of remote drive and device command line multi-process: refractor vl.c code to re-use in remote multi-process: add remote option multi-process: add remote options parser multi-process: add parse_cmdline in remote process multi-process: add support for multiple devices multi-process: add heartbeat timer and signal handler multi-process: handle heartbeat messages in remote process multi-process: add configure and usage information Jagannathan Raman (24): multi-process: memory: alloc RAM from file at offset multi-process: util: Add qemu_thread_cancel() to cancel running thread multi-process: Add stub functions to facilate build of multi-process multi-process: Add config option for multi-process QEMU multi-process: build system for remote device process multi-process: define proxy-link object multi-process: add functions to synchronize proxy and remote endpoints multi-process: setup PCI host bridge for remote device multi-process: setup a machine object for remote device process multi-process: setup memory manager for remote device multi-process: remote process initialization multi-process: PCI BAR read/write handling for proxy & remote endpoints multi-process: Add LSI device proxy object multi-process: Synchronize remote memory multi-process: create IOHUB object to handle irq multi-process: Introduce build flags to separate remote process code multi-process: Use separate MMIO communication channel multi-process: perform device reset in the remote process multi-process/mon: stub functions to enable QMP module for remote process multi-process/mon: build system for QMP module in remote process multi-process/mon: Refactor monitor/chardev functions out of vl.c multi-process/mon: trim HMP command set for remote storage processes multi-process/mon: Initialize QMP module for remote processes multi-process: prevent duplicate memory initialization in remote John G Johnson (1): multi-process: add the concept description to docs/devel/qemu-multiprocess Makefile | 2 + Makefile.objs | 33 ++ Makefile.target | 91 +++++- accel/stubs/kvm-stub.c | 5 + accel/stubs/tcg-stub.c | 95 ++++++ backends/Makefile.objs | 2 + block/Makefile.objs | 2 + configure | 15 + docs/devel/qemu-multiprocess.txt | 627 ++++++++++++++++++++++++++++++++++++ docs/qemu-multiprocess.txt | 86 +++++ exec.c | 14 +- hmp-scsi-commands-info.hx | 167 ++++++++++ hmp-scsi-commands.hx | 384 ++++++++++++++++++++++ hw/Makefile.objs | 9 + hw/block/Makefile.objs | 2 + hw/core/Makefile.objs | 16 + hw/nvram/Makefile.objs | 2 + hw/pci/Makefile.objs | 4 + hw/proxy/Makefile.objs | 1 + hw/proxy/memory-sync.c | 226 +++++++++++++ hw/proxy/proxy-lsi53c895a.c | 168 ++++++++++ hw/proxy/qemu-proxy.c | 615 +++++++++++++++++++++++++++++++++++ hw/scsi/Makefile.objs | 2 + include/exec/address-spaces.h | 2 + include/exec/ram_addr.h | 2 +- include/glib-compat.h | 4 + include/hw/pci/pci_ids.h | 3 + include/hw/proxy/memory-sync.h | 51 +++ include/hw/proxy/proxy-lsi53c895a.h | 42 +++ include/hw/proxy/qemu-proxy.h | 106 ++++++ include/hw/qdev-core.h | 2 + include/io/proxy-link.h | 202 ++++++++++++ include/monitor/qdev.h | 24 ++ include/qemu-common.h | 8 + include/qemu/log.h | 1 + include/qemu/mmap-alloc.h | 3 +- include/qemu/thread.h | 1 + include/remote/iohub.h | 63 ++++ include/remote/machine.h | 48 +++ include/remote/memory.h | 34 ++ include/remote/pcihost.h | 59 ++++ io/Makefile.objs | 2 + io/proxy-link.c | 363 +++++++++++++++++++++ memory.c | 2 +- migration/Makefile.objs | 2 + monitor/Makefile.objs | 3 + monitor/misc.c | 84 ++--- monitor/monitor-internal.h | 38 +++ qapi/Makefile.objs | 2 + qdev-monitor.c | 257 ++++++++++++++- qemu-options.hx | 21 ++ qom/Makefile.objs | 5 + remote/Makefile.objs | 6 + remote/iohub.c | 159 +++++++++ remote/machine.c | 133 ++++++++ remote/memory.c | 99 ++++++ remote/pcihost.c | 84 +++++ remote/remote-main.c | 626 +++++++++++++++++++++++++++++++++++ remote/remote-opts.c | 123 +++++++ remote/remote-opts.h | 31 ++ rules.mak | 2 +- stubs/gdbstub.c | 21 ++ stubs/machine-init-done.c | 4 + stubs/migration.c | 162 ++++++++++ stubs/monitor.c | 65 ++++ stubs/net-stub.c | 100 ++++++ stubs/qapi-misc.c | 41 +++ stubs/qapi-target.c | 49 +++ stubs/replay.c | 18 ++ stubs/ui-stub.c | 130 ++++++++ stubs/vl-stub.c | 169 ++++++++++ stubs/vmstate.c | 20 ++ stubs/xen-mapcache.c | 22 ++ ui/Makefile.objs | 2 + util/log.c | 2 + util/mmap-alloc.c | 7 +- util/oslib-posix.c | 2 +- util/qemu-thread-posix.c | 10 + vl-parse.c | 249 ++++++++++++++ vl.c | 298 ++++++++--------- vl.h | 58 ++++ 81 files changed, 6466 insertions(+), 228 deletions(-) create mode 100644 docs/devel/qemu-multiprocess.txt create mode 100644 docs/qemu-multiprocess.txt create mode 100644 hmp-scsi-commands-info.hx create mode 100644 hmp-scsi-commands.hx create mode 100644 hw/proxy/Makefile.objs create mode 100644 hw/proxy/memory-sync.c create mode 100644 hw/proxy/proxy-lsi53c895a.c create mode 100644 hw/proxy/qemu-proxy.c create mode 100644 include/hw/proxy/memory-sync.h create mode 100644 include/hw/proxy/proxy-lsi53c895a.h create mode 100644 include/hw/proxy/qemu-proxy.h create mode 100644 include/io/proxy-link.h create mode 100644 include/remote/iohub.h create mode 100644 include/remote/machine.h create mode 100644 include/remote/memory.h create mode 100644 include/remote/pcihost.h create mode 100644 io/proxy-link.c create mode 100644 remote/Makefile.objs create mode 100644 remote/iohub.c create mode 100644 remote/machine.c create mode 100644 remote/memory.c create mode 100644 remote/pcihost.c create mode 100644 remote/remote-main.c create mode 100644 remote/remote-opts.c create mode 100644 remote/remote-opts.h create mode 100644 stubs/migration.c create mode 100644 stubs/net-stub.c create mode 100644 stubs/qapi-misc.c create mode 100644 stubs/qapi-target.c create mode 100644 stubs/ui-stub.c create mode 100644 stubs/vl-stub.c create mode 100644 stubs/xen-mapcache.c create mode 100644 vl-parse.c create mode 100644 vl.h -- 1.8.3.1