tree 45ec104bbccf3a4a660f8e9d0309912b96db50d2
parent b67c9effd31e1c10a270cefd217ff586b557ee2e
author Jorim Jaggi <jjaggi@google.com> 1637258979 +0100
committer Jorim Jaggi <jjaggi@google.com> 1639086781 +0100

Add cheap aidl tracing suitable for always-on-tracing (3/3)

Instead of having only one switch to enable all binder tracing,
we seperate between stack tracking and tracing. Stack tracking
still works as before. However, the more lightweight option,
tracing using android.os.Trace, is toggleable separately and will
work on the receiver side without dumping the entire stack trace.

We also make the tracing more efficient by caching
getTransactionName and concatting the class name.

Also, enable this selectively for SysUI+Launcher, which is
currently the focus of always-on-tracing effort to figure out
what kind of binder calls these processes are calling which seems
to contribute a huge amount of jank (long binder calls are in
>= 50% of janky traces).

Test: external/perfetto/tools/record_android_trace gfx view freq sched wm am aidl
Test: atest aidl_unittest
Bug: 202278427
Change-Id: Ia555740400808e0a467d00e305b6743931d3af0a