Skip to content

Commit

Permalink
Revert "bpo-40513: Per-interpreter signals pending (GH-19924)" (GH-19932
Browse files Browse the repository at this point in the history 
)

This reverts commit 4e01946.
  • Loading branch information
@vstinner
vstinner authored May 5, 2020
1 parent 6351d9e commit 299b8c6
Show file tree
Hide file tree
Showing 4 changed files with 42 additions and 32 deletions.
2 changes: 0 additions & 2 deletions Include/internal/pycore_interp.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -46,8 +46,6 @@ struct _ceval_state {
/* Request for dropping the GIL */
_Py_atomic_int gil_drop_request;
struct _pending_calls pending;
/* Request for checking signals. */
_Py_atomic_int signals_pending;
};


Expand Down
5 changes: 5 additions & 0 deletions Include/internal/pycore_runtime.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -14,6 +14,11 @@ extern "C" {
/* ceval state */

struct _ceval_runtime_state {
/* Request for checking signals. It is shared by all interpreters (see
bpo-40513). Any thread of any interpreter can receive a signal, but only
the main thread of the main interpreter can handle signals: see
_Py_ThreadCanHandleSignals(). */
_Py_atomic_int signals_pending;
struct _gil_runtime_state gil;
};

Expand Down
65 changes: 36 additions & 29 deletions Python/ceval.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -143,70 +143,76 @@ is_tstate_valid(PyThreadState *tstate)
the GIL eventually anyway. */
static inline void
COMPUTE_EVAL_BREAKER(PyInterpreterState *interp,
struct _ceval_state *ceval)
struct _ceval_runtime_state *ceval,
struct _ceval_state *ceval2)
{
_Py_atomic_store_relaxed(&ceval->eval_breaker,
_Py_atomic_load_relaxed(&ceval->gil_drop_request)
_Py_atomic_store_relaxed(&ceval2->eval_breaker,
_Py_atomic_load_relaxed(&ceval2->gil_drop_request)
| (_Py_atomic_load_relaxed(&ceval->signals_pending)
&& _Py_ThreadCanHandleSignals(interp))
| (_Py_atomic_load_relaxed(&ceval->pending.calls_to_do)
| (_Py_atomic_load_relaxed(&ceval2->pending.calls_to_do)
&& _Py_ThreadCanHandlePendingCalls())
| ceval->pending.async_exc);
| ceval2->pending.async_exc);
}


static inline void
SET_GIL_DROP_REQUEST(PyInterpreterState *interp)
{
struct _ceval_state *ceval = &interp->ceval;
_Py_atomic_store_relaxed(&ceval->gil_drop_request, 1);
_Py_atomic_store_relaxed(&ceval->eval_breaker, 1);
struct _ceval_state *ceval2 = &interp->ceval;
_Py_atomic_store_relaxed(&ceval2->gil_drop_request, 1);
_Py_atomic_store_relaxed(&ceval2->eval_breaker, 1);
}


static inline void
RESET_GIL_DROP_REQUEST(PyInterpreterState *interp)
{
struct _ceval_state *ceval = &interp->ceval;
_Py_atomic_store_relaxed(&ceval->gil_drop_request, 0);
COMPUTE_EVAL_BREAKER(interp, ceval);
struct _ceval_runtime_state *ceval = &interp->runtime->ceval;
struct _ceval_state *ceval2 = &interp->ceval;
_Py_atomic_store_relaxed(&ceval2->gil_drop_request, 0);
COMPUTE_EVAL_BREAKER(interp, ceval, ceval2);
}


static inline void
SIGNAL_PENDING_CALLS(PyInterpreterState *interp)
{
struct _ceval_state *ceval = &interp->ceval;
_Py_atomic_store_relaxed(&ceval->pending.calls_to_do, 1);
COMPUTE_EVAL_BREAKER(interp, ceval);
struct _ceval_runtime_state *ceval = &interp->runtime->ceval;
struct _ceval_state *ceval2 = &interp->ceval;
_Py_atomic_store_relaxed(&ceval2->pending.calls_to_do, 1);
COMPUTE_EVAL_BREAKER(interp, ceval, ceval2);
}


static inline void
UNSIGNAL_PENDING_CALLS(PyInterpreterState *interp)
{
struct _ceval_state *ceval = &interp->ceval;
_Py_atomic_store_relaxed(&ceval->pending.calls_to_do, 0);
COMPUTE_EVAL_BREAKER(interp, ceval);
struct _ceval_runtime_state *ceval = &interp->runtime->ceval;
struct _ceval_state *ceval2 = &interp->ceval;
_Py_atomic_store_relaxed(&ceval2->pending.calls_to_do, 0);
COMPUTE_EVAL_BREAKER(interp, ceval, ceval2);
}


static inline void
SIGNAL_PENDING_SIGNALS(PyInterpreterState *interp)
{
struct _ceval_state *ceval = &interp->ceval;
struct _ceval_runtime_state *ceval = &interp->runtime->ceval;
struct _ceval_state *ceval2 = &interp->ceval;
_Py_atomic_store_relaxed(&ceval->signals_pending, 1);
/* eval_breaker is not set to 1 if thread_can_handle_signals() is false */
COMPUTE_EVAL_BREAKER(interp, ceval);
COMPUTE_EVAL_BREAKER(interp, ceval, ceval2);
}


static inline void
UNSIGNAL_PENDING_SIGNALS(PyInterpreterState *interp)
{
struct _ceval_state *ceval = &interp->ceval;
struct _ceval_runtime_state *ceval = &interp->runtime->ceval;
struct _ceval_state *ceval2 = &interp->ceval;
_Py_atomic_store_relaxed(&ceval->signals_pending, 0);
COMPUTE_EVAL_BREAKER(interp, ceval);
COMPUTE_EVAL_BREAKER(interp, ceval, ceval2);
}


Expand All @@ -222,9 +228,10 @@ SIGNAL_ASYNC_EXC(PyInterpreterState *interp)
static inline void
UNSIGNAL_ASYNC_EXC(PyInterpreterState *interp)
{
struct _ceval_state *ceval = &interp->ceval;
ceval->pending.async_exc = 0;
COMPUTE_EVAL_BREAKER(interp, ceval);
struct _ceval_runtime_state *ceval = &interp->runtime->ceval;
struct _ceval_state *ceval2 = &interp->ceval;
ceval2->pending.async_exc = 0;
COMPUTE_EVAL_BREAKER(interp, ceval, ceval2);
}


Expand Down Expand Up @@ -349,11 +356,12 @@ PyEval_ReleaseLock(void)
{
_PyRuntimeState *runtime = &_PyRuntime;
PyThreadState *tstate = _PyRuntimeState_GetThreadState(runtime);
struct _ceval_state *ceval2 = &tstate->interp->ceval;
/* This function must succeed when the current thread state is NULL.
We therefore avoid PyThreadState_Get() which dumps a fatal error
in debug mode. */
drop_gil(&runtime->ceval, ceval2, tstate);
struct _ceval_runtime_state *ceval = &runtime->ceval;
struct _ceval_state *ceval2 = &tstate->interp->ceval;
drop_gil(ceval, ceval2, tstate);
}

void
Expand Down Expand Up @@ -435,7 +443,6 @@ PyThreadState *
PyEval_SaveThread(void)
{
_PyRuntimeState *runtime = &_PyRuntime;

PyThreadState *tstate = _PyThreadState_Swap(&runtime->gilstate, NULL);
ensure_tstate_not_null(__func__, tstate);

Expand Down Expand Up @@ -831,16 +838,16 @@ eval_frame_handle_pending(PyThreadState *tstate)
{
_PyRuntimeState * const runtime = &_PyRuntime;
struct _ceval_runtime_state *ceval = &runtime->ceval;
struct _ceval_state *ceval2 = &tstate->interp->ceval;

/* Pending signals */
if (_Py_atomic_load_relaxed(&ceval2->signals_pending)) {
if (_Py_atomic_load_relaxed(&ceval->signals_pending)) {
if (handle_signals(tstate) != 0) {
return -1;
}
}

/* Pending calls */
struct _ceval_state *ceval2 = &tstate->interp->ceval;
if (_Py_atomic_load_relaxed(&ceval2->pending.calls_to_do)) {
if (make_pending_calls(tstate) != 0) {
return -1;
Expand Down
2 changes: 1 addition & 1 deletion Python/ceval_gil.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -305,7 +305,7 @@ take_gil(PyThreadState *tstate)
handle signals.
Note: RESET_GIL_DROP_REQUEST() calls COMPUTE_EVAL_BREAKER(). */
COMPUTE_EVAL_BREAKER(interp, ceval2);
COMPUTE_EVAL_BREAKER(interp, ceval, ceval2);
}

/* Don't access tstate if the thread must exit */
Expand Down

0 comments on commit 299b8c6

Please sign in to comment.