Many of the zones would have a negative running time due to a missing `cs->IsEndValid()` check.
This could end reporting context switches before the zone start, due to `cs->End()` returning -1.
This happened when systrace dropped event, or when using Fibers and `TracyFiberEnter` is called on the new thread once the fiber has been scheduled. (The manual actually does not really hint this is wrong, we should probably fix the manual or the server code.)
In both cases, we assume runtime to be 0 for that context switch. Since we have no actual information. Both options (counting full runtime or no runtime) are wrong, and most of the code handling `!cs->IsEndValid()` uses `Start` instead so that's what I did. This is still a net improvement over displaying negative values. If we want to change this handling, we'd need to review the other places that do `it->IsEndValid() ? it->End() : it->Start()` as well.
It also seems two different concepts were being mixed:
1. Do we have any context switch data at all ? (`it != ctx->v.end()` ie `count != 0`)
2. Do we have complete data for the last context switch (`eit != ctx->v.end()`)
This led to some places of the code not displaying or counting running time at all, notably when hovering a zone.
I think most of the time we wanted 1, as it reports correctly and assumes the last context switch is still running, which is a fair assumption if we didn't see one putting the thread to sleep.
I also fixed a case where we were overcounting runtime when range start was during a sleep.
This PR does the following things:
- Allow to lock the highlighted thread using left mouse click or lane popup menu
- Add more descriptions for wait reasons in View::DecodeContextSwitchReason
- Stores the Wakeup CPU so that we may display it in the CPU data view
- `QueueThreadWakeup` now contains cpu and adjust info (currently unused). Fits in the padding, no struct size change.
- `QueueContextSwitch` now also contains thread priorities information (windows+linux) and CState (windows), but currently unused by the profiler. Fits in the padding, no struct size change.
- Fixes Linux `EventWakeup` which tries to remove PERF_SAMPLE_CALLCHAIN on the wrong member. Set the whole `perf_event_attr` explicitely instead.
- Fixes Windows ReadyThread event being dropped if triggered before the thread switches out (this is confirmed to be normal behaviour, probably due to thread being switched out but context switch actually happening later)
- Bumps tracy file version and protocol versions
Context switch callstack samples are not included in the sampling data
statistics (as these don't represent random sampling), but are rather put into
a separate dedicated data structure.
For this to work, a complete context switch data has to be available for the
callstack timestamp. There is no guarantee it will be present at the time it
is needed, so a second structure is added to allow postponing qualification of
callstacks.
Add to ThreadData a map from source location to a counter,
which will be used to keep track of the number of
appearances of zones with the corresponding source locations
on each thread's stack.
