1 #ifndef Py_INTERNAL_GIL_H 2 #define Py_INTERNAL_GIL_H 3 #ifdef __cplusplus 4 extern "C" { 5 #endif 6 7 #ifndef Py_BUILD_CORE 8 # error "this header requires Py_BUILD_CORE define" 9 #endif 10 11 #include "pycore_atomic.h" /* _Py_atomic_address */ 12 #include "pycore_condvar.h" /* PyCOND_T */ 13 14 #ifndef Py_HAVE_CONDVAR 15 # error You need either a POSIX-compatible or a Windows system! 16 #endif 17 18 /* Enable if you want to force the switching of threads at least 19 every `interval`. */ 20 #undef FORCE_SWITCHING 21 #define FORCE_SWITCHING 22 23 struct _gil_runtime_state { 24 /* microseconds (the Python API uses seconds, though) */ 25 unsigned long interval; 26 /* Last PyThreadState holding / having held the GIL. This helps us 27 know whether anyone else was scheduled after we dropped the GIL. */ 28 _Py_atomic_address last_holder; 29 /* Whether the GIL is already taken (-1 if uninitialized). This is 30 atomic because it can be read without any lock taken in ceval.c. */ 31 _Py_atomic_int locked; 32 /* Number of GIL switches since the beginning. */ 33 unsigned long switch_number; 34 /* This condition variable allows one or several threads to wait 35 until the GIL is released. In addition, the mutex also protects 36 the above variables. */ 37 PyCOND_T cond; 38 PyMUTEX_T mutex; 39 #ifdef FORCE_SWITCHING 40 /* This condition variable helps the GIL-releasing thread wait for 41 a GIL-awaiting thread to be scheduled and take the GIL. */ 42 PyCOND_T switch_cond; 43 PyMUTEX_T switch_mutex; 44 #endif 45 }; 46 47 #ifdef __cplusplus 48 } 49 #endif 50 #endif /* !Py_INTERNAL_GIL_H */ 51