mbox series

[v4,00/18] TCG Plugin inline operation enhancement

Message ID 20240213094009.150349-1-pierrick.bouvier@linaro.org
Headers show
Series TCG Plugin inline operation enhancement | expand

Message

Pierrick Bouvier Feb. 13, 2024, 9:39 a.m. UTC 
This series adds a new thread-safe API to declare inline operation
inside plugins. As well, it removes the existing non thread-safe API,
and migrates all existing plugins to use it.

Tested on Linux (user, system) for i386, x86_64 and aarch64.

To give some context, this a long term series of work around plugins,
with the goal to be able to do basic operations in a more performant and
accurate way. This will mean to add more inline operations and
conditional callbacks.

One final target of this work is to implement a plugin that implements
the icount=auto feature, and allow QEMU to run at a given "frequency"
based on number of instructions executed, without QEMU needing to keep
track of this.

Another final target is to be able to detect control flow changes in an
efficient and elegant way, by combining inline operation and conditional
callbacks.

v2
--

Implement scoreboard API (cpu local storage), so plugins don't have to deal
with how many cpus are used.

Since plugins have been modified again, I didn't transfer any reviewed-by on
those commits.

v3
--

- introduce qemu_plugin_num_vcpus (how many cpus were initialized)
- fix order of plugin init/idle/resume callbacks
- scoreboard:
  - renamed qemu_plugin_u64_t -> qemu_plugin_u64
  - some functions rename for scoreboard api
  - qemu_plugin_u64 has only value based function (vs address before)
- various cleanup thanks to review of previous series

v4
--

- split scoreboard/qemu_plugin_u64 patches
- use list instead of hash table to keep track of scoreboards
- remove immediate in tcg code gen

Based-on: 20240122145610.413836-1-alex.bennee@linaro.org

 Version number: 4
 Branches:
          base:  plugin_registers_v3_20240122145610.413836-1-alex.bennee@linaro.org
          topic: plugin_inline_per_vcpu

Pierrick Bouvier (18):
  plugins: remove previous n_vcpus functions from API
  plugins: add qemu_plugin_num_vcpus function
  plugins: fix order of init/idle/resume callback
  cpu: call plugin init hook asynchronously
  plugins: scoreboard API
  plugins: define qemu_plugin_u64
  docs/devel: plugins can trigger a tb flush
  plugins: implement inline operation relative to cpu_index
  plugins: add inline operation per vcpu
  tests/plugin: add test plugin for inline operations
  tests/plugin/mem: migrate to new per_vcpu API
  tests/plugin/insn: migrate to new per_vcpu API
  tests/plugin/bb: migrate to new per_vcpu API
  contrib/plugins/hotblocks: migrate to new per_vcpu API
  contrib/plugins/howvec: migrate to new per_vcpu API
  plugins: remove non per_vcpu inline operation from API
  plugins: cleanup codepath for previous inline operation
  MAINTAINERS: Add myself as reviewer for TCG Plugins

 MAINTAINERS                     |   1 +
 docs/devel/multi-thread-tcg.rst |   1 +
 include/qemu/plugin.h           |   7 ++
 include/qemu/qemu-plugin.h      | 151 ++++++++++++++++++++------
 plugins/plugin.h                |  23 ++--
 accel/tcg/plugin-gen.c          |  69 +++++++++---
 contrib/plugins/cache.c         |   2 +-
 contrib/plugins/hotblocks.c     |  50 +++++----
 contrib/plugins/howvec.c        |  53 ++++++---
 hw/core/cpu-common.c            |   9 +-
 plugins/api.c                   | 121 +++++++++++++--------
 plugins/core.c                  |  94 ++++++++++++++--
 tests/plugin/bb.c               |  63 +++++------
 tests/plugin/inline.c           | 186 ++++++++++++++++++++++++++++++++
 tests/plugin/insn.c             | 106 +++++++++---------
 tests/plugin/mem.c              |  40 ++++---
 plugins/qemu-plugins.symbols    |  16 ++-
 tests/plugin/meson.build        |   2 +-
 18 files changed, 737 insertions(+), 257 deletions(-)
 create mode 100644 tests/plugin/inline.c

Comments

Alex Bennée Feb. 16, 2024, 4:20 p.m. UTC | #1 
Pierrick Bouvier <pierrick.bouvier@linaro.org> writes:

> This series adds a new thread-safe API to declare inline operation
> inside plugins. As well, it removes the existing non thread-safe API,
> and migrates all existing plugins to use it.
>
> Tested on Linux (user, system) for i386, x86_64 and aarch64.
<snip>
>
> Pierrick Bouvier (18):
>   plugins: remove previous n_vcpus functions from API
>   plugins: add qemu_plugin_num_vcpus function
>   plugins: fix order of init/idle/resume callback
>   cpu: call plugin init hook asynchronously
>   docs/devel: plugins can trigger a tb flush

I've queued these into the maintainer pre-PR series I'm about to send as
I need the callback fixes to make the register code safe.