altman08 opened a new pull request, #3380:
URL: https://github.com/apache/brpc/pull/3380

   Route accesses to tls_task_group, tls_task_group_nosignal, tls_bls and 
several mutex-profiling thread-locals (tls_inside_lock, tls_warn_up, 
tls_pthread_lock_count, tls_csites, tls_ever_created_keytable) through the 
BAIDU_(GET|SET|GET_PTR)_VOLATILE_THREAD_LOCAL macros instead of touching the 
raw __thread variables directly.
   
   On aarch64/clang the compiler can incorrectly cache the address of a 
thread_local variable across a suspend point (e.g. when a bthread is 
rescheduled onto another worker), so raw accesses can silently read a stale 
TaskGroup*/LocalStorage. Going through the accessor macros everywhere forces a 
fresh, non-cached load/store on those platforms while staying a plain variable 
access elsewhere.
   
   Add bthread::tls_bls_ptr() as the single helper for obtaining the current 
LocalStorage*, and update all call sites (bthread.cpp, butex.cpp, fd.cpp, 
key.cpp, mutex.cpp, task_control.cpp, brpc/controller.cpp, 
test/bthread_unittest.cpp) to use it instead of declaring their own 
stale/mistyped extern references to tls_task_group or tls_bls.
   
   Also hardens borrow_keytable()/return_keytable() in key.cpp: the 
KeyTableList pointer obtained under the read lock is no longer reused after 
re-acquiring the write lock, since pool->list/pool->destroyed may change 
concurrently via bthread_keytable_pool_destroy(); the thread-local list is 
drained first before falling back to the pool's global free list.
   
   ### 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:
   - Please make sure your changes are compilable.
   - When providing us with a new feature, it is best to add related tests.
   - Please follow [Contributor Covenant Code of 
Conduct](https://github.com/apache/brpc/blob/master/CODE_OF_CONDUCT.md).
   


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