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Diffstat (limited to 'Include/internal/_gil.h')
| -rw-r--r-- | Include/internal/_gil.h | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/Include/internal/_gil.h b/Include/internal/_gil.h new file mode 100644 index 0000000..42301bf --- /dev/null +++ b/Include/internal/_gil.h @@ -0,0 +1,48 @@ +#ifndef _Py_GIL_H +#define _Py_GIL_H +#ifdef __cplusplus +extern "C" { +#endif + +#include "pyatomic.h" + +#include "internal/_condvar.h" +#ifndef Py_HAVE_CONDVAR +#error You need either a POSIX-compatible or a Windows system! +#endif + +/* Enable if you want to force the switching of threads at least + every `interval`. */ +#undef FORCE_SWITCHING +#define FORCE_SWITCHING + +struct _gil_runtime_state { + /* microseconds (the Python API uses seconds, though) */ + unsigned long interval; + /* Last PyThreadState holding / having held the GIL. This helps us + know whether anyone else was scheduled after we dropped the GIL. */ + _Py_atomic_address last_holder; + /* Whether the GIL is already taken (-1 if uninitialized). This is + atomic because it can be read without any lock taken in ceval.c. */ + _Py_atomic_int locked; + /* Number of GIL switches since the beginning. */ + unsigned long switch_number; +#ifdef WITH_THREAD + /* This condition variable allows one or several threads to wait + until the GIL is released. In addition, the mutex also protects + the above variables. */ + PyCOND_T cond; + PyMUTEX_T mutex; +#ifdef FORCE_SWITCHING + /* This condition variable helps the GIL-releasing thread wait for + a GIL-awaiting thread to be scheduled and take the GIL. */ + PyCOND_T switch_cond; + PyMUTEX_T switch_mutex; +#endif +#endif /* WITH_THREAD */ +}; + +#ifdef __cplusplus +} +#endif +#endif /* !_Py_GIL_H */ |