bindings: python: release the GIL during blocking I/O operations

We should release the python global interpreter lock when performing
blocking operations and reacquire it again when we're done. Use the
relevant APIs provided by libpython.

Signed-off-by: Bartosz Golaszewski <bartekgola@gmail.com>

diff --git a/bindings/python/gpiodmodule.c b/bindings/python/gpiodmodule.c
index d1e6f1ed187f2af87e975fb28afc4d9de830bc03..2b4eddc9030265689b07d46cea91885a49fd7b27 100644 (file)
--- a/bindings/python/gpiodmodule.c
+++ b/bindings/python/gpiodmodule.c
@@ -447,7 +447,9 @@ static gpiod_LineEventObject *gpiod_Line_event_read(gpiod_LineObject *self)
 
        ret->source = NULL;
 
+       Py_BEGIN_ALLOW_THREADS;
        rv = gpiod_line_event_read(self->line, &ret->event);
+       Py_END_ALLOW_THREADS;
        if (rv) {
                PyErr_SetFromErrno(PyExc_OSError);
                Py_DECREF(ret);
@@ -843,7 +845,9 @@ static PyObject *gpiod_LineBulk_request(gpiod_LineBulkObject *self,
                }
        }
 
+       Py_BEGIN_ALLOW_THREADS;
        rv = gpiod_line_request_bulk(&bulk, &conf, default_vals);
+       Py_END_ALLOW_THREADS;
        if (rv) {
                PyErr_SetFromErrno(PyExc_OSError);
                return NULL;
@@ -865,7 +869,9 @@ static PyObject *gpiod_LineBulk_get_values(gpiod_LineBulkObject *self)
        gpiod_LineBulkObjToCLineBulk(self, &bulk);
 
        memset(vals, 0, sizeof(vals));
+       Py_BEGIN_ALLOW_THREADS;
        rv = gpiod_line_get_value_bulk(&bulk, vals);
+       Py_END_ALLOW_THREADS;
        if (rv) {
                PyErr_SetFromErrno(PyExc_OSError);
                return NULL;
@@ -937,7 +943,9 @@ static PyObject *gpiod_LineBulk_set_values(gpiod_LineBulkObject *self,
                vals[i] = (int)val;
        }
 
+       Py_BEGIN_ALLOW_THREADS;
        rv = gpiod_line_set_value_bulk(&bulk, vals);
+       Py_END_ALLOW_THREADS;
        if (rv) {
                PyErr_SetFromErrno(PyExc_OSError);
                return NULL;
@@ -987,7 +995,9 @@ static PyObject *gpiod_LineBulk_event_wait(gpiod_LineBulkObject *self,
 
        gpiod_LineBulkObjToCLineBulk(self, &bulk);
 
+       Py_BEGIN_ALLOW_THREADS;
        rv = gpiod_line_event_wait_bulk(&bulk, &ts, &ev_bulk);
+       Py_END_ALLOW_THREADS;
        if (rv < 0) {
                PyErr_SetFromErrno(PyExc_OSError);
                return NULL;
@@ -1146,12 +1156,14 @@ enum {
 static int gpiod_Chip_init(gpiod_ChipObject *self, PyObject *args)
 {
        int rv, how = gpiod_OPEN_LOOKUP;
+       PyThreadState *thread;
        char *descr;
 
        rv = PyArg_ParseTuple(args, "s|i", &descr, &how);
        if (!rv)
                return -1;
 
+       thread = PyEval_SaveThread();
        switch (how) {
        case gpiod_OPEN_LOOKUP:
                self->chip = gpiod_chip_open_lookup(descr);
@@ -1169,9 +1181,11 @@ static int gpiod_Chip_init(gpiod_ChipObject *self, PyObject *args)
                self->chip = gpiod_chip_open_by_number(atoi(descr));
                break;
        default:
+               PyEval_RestoreThread(thread);
                PyErr_BadArgument();
                return -1;
        }
+       PyEval_RestoreThread(thread);
        if (!self->chip) {
                PyErr_SetFromErrno(PyExc_OSError);
                return -1;
@@ -1248,7 +1262,9 @@ gpiod_Chip_get_line(gpiod_ChipObject *self, PyObject *args)
        if (!rv)
                return NULL;
 
+       Py_BEGIN_ALLOW_THREADS;
        line = gpiod_chip_get_line(self->chip, offset);
+       Py_END_ALLOW_THREADS;
        if (!line) {
                PyErr_SetFromErrno(PyExc_OSError);
                return NULL;
@@ -1271,7 +1287,9 @@ gpiod_Chip_find_line(gpiod_ChipObject *self, PyObject *args)
        if (!rv)
                return NULL;
 
+       Py_BEGIN_ALLOW_THREADS;
        line = gpiod_chip_find_line(self->chip, name);
+       Py_END_ALLOW_THREADS;
        if (!line) {
                PyErr_SetFromErrno(PyExc_OSError);
                return NULL;
@@ -1444,7 +1462,9 @@ static gpiod_ChipObject *gpiod_ChipIter_next(gpiod_ChipIterObject *self)
        gpiod_ChipObject *chip_obj;
        struct gpiod_chip *chip;
 
+       Py_BEGIN_ALLOW_THREADS;
        chip = gpiod_chip_iter_next_noclose(self->iter);
+       Py_END_ALLOW_THREADS;
        if (!chip)
                return NULL; /* Last element. */
 
@@ -1485,7 +1505,9 @@ static int gpiod_LineIter_init(gpiod_LineIterObject *self, PyObject *args)
        if (!rv)
                return -1;
 
+       Py_BEGIN_ALLOW_THREADS;
        self->iter = gpiod_line_iter_new(chip_obj->chip);
+       Py_END_ALLOW_THREADS;
        if (!self->iter) {
                PyErr_SetFromErrno(PyExc_OSError);
                return -1;
@@ -1546,7 +1568,9 @@ static gpiod_LineObject *gpiod_Module_find_line(PyObject *self GPIOD_UNUSED,
        if (!rv)
                return NULL;
 
+       Py_BEGIN_ALLOW_THREADS;
        line = gpiod_line_find(name);
+       Py_END_ALLOW_THREADS;
        if (!line) {
                PyErr_SetFromErrno(PyExc_OSError);
                return NULL;