Fix missing GC counter data on non-Windows

[elinor-fung]

This sets FEATURE_EVENT_TRACE on non-Windows platforms as well, such that GC counter information is tracked and provided when requested.

This is only enough to enable the counter tracking (#87325). It does not fully enable event tracing via EventPipe on non-Windows.

I manually verified by running dotnet-counters monitor. The automated tests just verify the counters can be retrieved - which they could before, but some of them were just always 0.

Pulling in whatever is under FEATURE_EVENT_TRACE seems to be about +25kB on my helloworld app.

[ghost]

Tagging subscribers to this area: @agocke, @MichalStrehovsky, @jkotas
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Issue Details

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This sets FEATURE_EVENT_TRACE on non-Windows platforms as well, such that GC counter information is tracked and provided when requested.

This is only enough to enable the counter tracking (#87325). It does not fully enable event tracing via EventPipe on non-Windows.

I manually verified by running dotnet-counters monitor. The automated tests just verify the counters can be retrieved - which they could before, but some of them were just always 0.

Author:	elinor-fung
Assignees:	-
Labels:	area-NativeAOT-coreclr
Milestone:	-

[LakshanF]

Thanks!

[agocke]

Pulling in whatever is under FEATURE_EVENT_TRACE seems to be about +25kB on my helloworld app.

Is that with the EventSource support enabled via feature flag? Otherwise I thought we managed to avoid pulling in the event source stuff in helloworld.

[MichalStrehovsky]

Pulling in whatever is under FEATURE_EVENT_TRACE seems to be about +25kB on my helloworld app.

Is that with the EventSource support enabled via feature flag? Otherwise I thought we managed to avoid pulling in the event source stuff in helloworld.

Only event pipe is separated out into an opt in library. We don't separate the event source support. I haven't looked how feasible it would be to put it into a separate static library that we could disable if event source is not enabled, but at 25 kB it's not worth too much effort.

[elinor-fung]

It is not with EventSource support enabled via feature flag. This enables code in the GC (currently enabled on Windows always) that keeps track of information that gets returned in counters - unlike eventpipe itself, we don't have separate enabled/disabled libs for the GC.