This series was born from this one: https://lists.gnu.org/archive/html/qemu-devel/2017-08/msg04310.html
The design comes from Markus, and also the whole-bunch-of discussions in previous thread. My heartful thanks to Markus, Daniel, Dave, Stefan, etc. on discussing the topic (...again!), providing shiny ideas and suggestions. Finally we got such a solution that seems to satisfy everyone. I re-started the versioning since this series is totally different from previous one. Now it's version 1. In case new reviewers come along the way without reading previous discussions, I will try to do a summary on what this is all about. What is OOB execution? ====================== It's the shortcut of Out-Of-Band execution, its name is given by Markus. It's a way to quickly execute a QMP request. Say, originally QMP is going throw these steps: JSON Parser --> QMP Dispatcher --> Respond /|\ (2) (3) | (1) | \|/ (4) +--------- main thread --------+ The requests are executed by the so-called QMP-dispatcher after the JSON is parsed. If OOB is on, we run the command directly in the parser and quickly returns. Yeah I know in current code the parser calls dispatcher directly (please see handle_qmp_command()). However it's not true again after this series (parser will has its own IO thread, and dispatcher will still be run in main thread). So this OOB does brings something different. There are more details on why OOB and the difference/relationship between OOB, async QMP, block/general jobs, etc.. but IMHO that's slightly out of topic (and believe me, it's not easy for me to summarize that). For more information, please refers to [1]. Summary ends here. Some Implementation Details =========================== Again, I mentioned that the old QMP workflow is this: JSON Parser --> QMP Dispatcher --> Respond /|\ (2) (3) | (1) | \|/ (4) +--------- main thread --------+ What this series does is, firstly: JSON Parser QMP Dispatcher --> Respond /|\ | /|\ (4) | | | (2) | (3) | (5) (1) | +-----> | \|/ +--------- main thread <-------+ And further: queue/kick JSON Parser ======> QMP Dispatcher --> Respond /|\ | (3) /|\ (4) | (1) | | (2) | | (5) | \|/ | \|/ IO thread main thread <-------+ Then it introduced the "allow-oob" parameter in QAPI schema to define commands, and "run-oob" flag to let oob-allowed command to run in the parser. The last patch enables this for "migrate-incoming" command. Please review. Thanks. [1] https://lists.gnu.org/archive/html/qemu-devel/2017-08/msg04310.html Peter Xu (15): char-io: fix possible race on IOWatchPoll qobject: allow NULL for qstring_get_str() qobject: introduce qobject_to_str() monitor: move skip_flush into monitor_data_init qjson: add "opaque" field to JSONMessageParser monitor: move the cur_mon hack deeper for QMP monitor: unify global init monitor: create IO thread monitor: allow to use IO thread for parsing monitor: introduce monitor_qmp_respond() monitor: separate QMP parser and dispatcher monitor: enable IO thread for (qmp & !mux) typed qapi: introduce new cmd option "allow-oob" qmp: support out-of-band (oob) execution qmp: let migrate-incoming allow out-of-band chardev/char-io.c | 15 ++- docs/devel/qapi-code-gen.txt | 51 ++++++- include/monitor/monitor.h | 2 +- include/qapi/qmp/dispatch.h | 2 + include/qapi/qmp/json-streamer.h | 8 +- include/qapi/qmp/qstring.h | 1 + monitor.c | 283 +++++++++++++++++++++++++++++++-------- qapi/introspect.json | 6 +- qapi/migration.json | 3 +- qapi/qmp-dispatch.c | 34 +++++ qga/main.c | 5 +- qobject/json-streamer.c | 7 +- qobject/qjson.c | 5 +- qobject/qstring.c | 13 +- scripts/qapi-commands.py | 19 ++- scripts/qapi-introspect.py | 10 +- scripts/qapi.py | 15 ++- scripts/qapi2texi.py | 2 +- tests/libqtest.c | 5 +- tests/qapi-schema/test-qapi.py | 2 +- trace-events | 2 + vl.c | 3 +- 22 files changed, 398 insertions(+), 95 deletions(-) -- 2.7.4