TiFlash failed to generate flamegraph

[CalvinNeo]

Bug Report

Please answer these questions before submitting your issue. Thanks!

After pingcap/tidb-engine-ext#193, we have to move from fp back to dwarf to unwind on x86 platforms. However, after this, flamegraph just can not work.

1. Minimal reproduce step (Required)

2. What did you expect to see? (Required)

3. What did you see instead (Required)

4. What is your TiFlash version? (Required)

[CalvinNeo]

We have already tried to recover:

1. no-omit-frame-pointer on rust side
2. rebuild std

However, only enable pprof-rs feature can make flamegraph work.

For any other cases, just stop at backtrace::trace_unsynchronized and never forward.

[CalvinNeo]

[CalvinNeo]

A demo with Proxy only https://github.com/calvinneo/tidb-engine-ext/tree/pprof-fail-demo

[CalvinNeo]

Change debug to 2, no help

[profile.test]
opt-level = 0
debug = 2
codegen-units = 16
lto = false
incremental = true
debug-assertions = true
overflow-checks = true
rpath = false

[mornyx]

Should be resolved by tikv/pprof-rs#172.