Perfetto support in radeonsi driver

What does this MR do and why?

Add support for perfetto tracing in radeonsi driver. Use -Dperfetto=true in meson build command to build radeonsi with perfetto support.

Changes:

• Add si_perfetto.h and si_perfetto.cpp files which contains data structures to keep intermediate state of tracing data source and also contains tracing events callbacks.

  • struct si_ds_device keeps the intermediate state of trace, struct si_ds_stage contains data for each render stages and struct si_ds_queue keeps all the render stages for a command stream.
  • si_ds_begin_##event_name and si_ds_end_##event_name are trace callbacks, it is called from u_trace once the timestamps from the GPU has been collected.

• Add si_utrace.h and si_utrace.c which contains initialization code for u_trace APIs and callbacks required in u_trace to emit timestamps in cmdstream and read back timestamps.

• Add si_ds_device, u_trace and si_ds_queue in si_context and initialize u_trace when creating context. u_trace contains trace event chunks with timestamp and payload, which is flushed to a queue in u_trace_context when driver flush the command stream to kernel code. u_trace_context processes the queue later in pctx->flush().

• Add si_tracepoints.py to create trace point functions in generated code si_tracepoints.h and si_tracepoints.c

• Add amd.cfg and modify system.cfg to provide data source configurations.

Collecting traces

1. Build Perfetto from sources available at subprojects/perfetto following this guide.
2. Go to the subprojects/perfetto directory and run a convenience script CONFIG=../../src/tool/pps/cfg/system.cfg OUT=out/linux/ ./tools/tmux -n
3. Start perfetto under the tmux session initiated in step 2
4. Once tracing has finished, you can detach from tmux with Ctrl+b, d, and the convenience script should automatically copy the trace files into tmp directory.
5. Go to ui.perfetto.dev and upload trace file by clicking on Open trace file