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| JNIEnv* env, jobject instance) { | ||
| return gettid(); | ||
| // Keep TLS initialization out of gettid(), which the signal handler also uses. | ||
| static thread_local const pid_t tid = gettid(); |
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instead of doing this - or in addition? - should we do add a ThreadLocal<Integer> on the Java side?
Use a ThreadLocal<Integer> in CpuProfiler to reuse the native thread ID when registering and restoring StarlarkThread instances. This avoids repeated JNI calls as well as native thread-ID lookups during map_each. Leave the native implementation and signal handler unchanged. Validation: EvalTests and ScriptTest passed. A two-thread check confirmed one native lookup per thread across 2,000 nested registrations. An actual CPU profiling run produced samples with the expected function names. RELNOTES: None
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Cache the native thread ID in a Java
ThreadLocal<Integer>inCpuProfiler. Repeated registration and restoration ofStarlarkThreadnow reuse the cached ID, avoiding both JNI calls and native thread-ID lookups. The C++ implementation is unchanged.Starlark
map_eachrepeatedly registers and restores the current thread while CPU profiling is enabled.Validation:
EvalTestsandScriptTestpassed. A two-thread check confirmed one native lookup per thread across 2,000 nested registrations, and a CPU profiling run produced 207 samples with the expected function names. Google Java Format andgit diff --checkpassed.RELNOTES: None
-zbarskybot