bthread: use BAIDU_GET_VOLATILE_THREAD_LOCAL to access tls_unique_use…#3393
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…r_ptr in sched_to tls_unique_user_ptr was read directly without going through the BAIDU_GET_VOLATILE_THREAD_LOCAL macro in TaskGroup::sched_to, while the paired write later in the same function correctly used BAIDU_SET_VOLATILE_THREAD_LOCAL. sched_to contains jump_stack, a suspend-point where GCC (aarch64) and Clang may incorrectly cache the address of a thread_local variable, which is exactly the hazard BAIDU_GET_VOLATILE_THREAD_LOCAL is designed to avoid. Fix the read to use the macro for consistency and correctness.
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LGTM |
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…r_ptr in sched_to
tls_unique_user_ptr was read directly without going through the BAIDU_GET_VOLATILE_THREAD_LOCAL macro in TaskGroup::sched_to, while the paired write later in the same function correctly used BAIDU_SET_VOLATILE_THREAD_LOCAL. sched_to contains jump_stack, a suspend-point where GCC (aarch64) and Clang may incorrectly cache the address of a thread_local variable, which is exactly the hazard BAIDU_GET_VOLATILE_THREAD_LOCAL is designed to avoid. Fix the read to use the macro for consistency and correctness.
What problem does this PR solve?
Issue Number: resolve
Problem Summary:
What is changed and the side effects?
Changed:
Side effects:
Performance effects:
Breaking backward compatibility:
Check List: