Add LockSupport TaskBlock profiling instrumentation

[kaahos]

What Does This Do

Add TaskBlock profiling instrumentation for LockSupport.park/unpark, including blocker and unblocking span attribution where available.

Motivation

LockSupport.park is widely used by executors, queues, schedulers, and virtual-thread internals. Capturing these park intervals as TaskBlock events makes parked time attributable to spans and easier to separate from active execution in wall-clock profiles.

Additional Notes

• Stacked on Add wallclock TaskBlock profiler support #11544
• Add DD_TRACE_LOCK_SUPPORT_ENABLED

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  • Get more information in this doc

Jira ticket: [PROJ-IDENT]

[datadog-official]

🎯 Code Coverage (details)
• Patch Coverage: 3.88%
• Overall Coverage: 54.92% (-2.02%)

_{This comment will be updated automatically if new data arrives.
🔗 Commit SHA: b795bf9 | Docs | Datadog PR Page | Give us feedback!}

[dd-octo-sts]

🔴 Java Benchmark SLOs — Performance SLO breach detected

Suite	Status
Startup	🔴 breach

SLO thresholds are defined here based on automatically generated metrics. A warning is raised when results are within 5% of the threshold.

PR vs. master results

Scenario	Candidate	master	Δ (95% CI of mean)
startup:insecure-bank:iast:Agent	14.82 s	14.63 s	[+0.5%; +2.0%] (maybe worse)
startup:insecure-bank:tracing:Agent	13.63 s	13.72 s	[-1.5%; +0.1%] (no difference)
startup:petclinic:appsec:Agent	16.88 s	16.83 s	[-0.5%; +1.2%] (no difference)
startup:petclinic:iast:Agent	16.33 s	16.97 s	[-8.0%; +0.4%] (no difference)
startup:petclinic:profiling:Agent	16.76 s	16.93 s	[-1.9%; -0.1%] (maybe better)
startup:petclinic:sca:Agent	16.91 s	16.53 s	[+1.1%; +3.5%] (significantly worse)
startup:petclinic:tracing:Agent	15.98 s	16.07 s	[-1.5%; +0.4%] (no difference)

Commit: 71c80707 · CI Pipeline · Benchmarking Platform UI

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Load and DaCapo benchmarks can be triggered manually in the GitLab pipeline. Results will appear in the Benchmarking Platform UI after completion.