diff options
Diffstat (limited to 'Python/pystate.c')
| -rw-r--r-- | Python/pystate.c | 33 |
1 files changed, 25 insertions, 8 deletions
diff --git a/Python/pystate.c b/Python/pystate.c index 2f1521e..b1e085b 100644 --- a/Python/pystate.c +++ b/Python/pystate.c @@ -2057,19 +2057,36 @@ _PyThreadState_Attach(PyThreadState *tstate) Py_FatalError("non-NULL old thread state"); } - _PyEval_AcquireLock(tstate); - // XXX assert(tstate_is_alive(tstate)); - current_fast_set(&_PyRuntime, tstate); - tstate_activate(tstate); + while (1) { + int acquired_gil = _PyEval_AcquireLock(tstate); - if (!tstate_try_attach(tstate)) { - tstate_wait_attach(tstate); - } + // XXX assert(tstate_is_alive(tstate)); + current_fast_set(&_PyRuntime, tstate); + tstate_activate(tstate); + + if (!tstate_try_attach(tstate)) { + tstate_wait_attach(tstate); + } #ifdef Py_GIL_DISABLED - _Py_qsbr_attach(((_PyThreadStateImpl *)tstate)->qsbr); + if (_PyEval_IsGILEnabled(tstate) != acquired_gil) { + // The GIL was enabled between our call to _PyEval_AcquireLock() + // and when we attached (the GIL can't go from enabled to disabled + // here because only a thread holding the GIL can disable + // it). Detach and try again. + assert(!acquired_gil); + tstate_set_detached(tstate, _Py_THREAD_DETACHED); + tstate_deactivate(tstate); + current_fast_clear(&_PyRuntime); + continue; + } + _Py_qsbr_attach(((_PyThreadStateImpl *)tstate)->qsbr); +#else + (void)acquired_gil; #endif + break; + } // Resume previous critical section. This acquires the lock(s) from the // top-most critical section. |