| Message ID | 20220524114610.41848-7-tomi.valkeinen@ideasonboard.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series |
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| Related | show |
Hi Tomi, Thank you for the patch. On Tue, May 24, 2022 at 02:45:57PM +0300, Tomi Valkeinen wrote: > Add CameraManager.read_event() so that the user does not need to call > os.read(). > > We use eventfd, and we must always read 8 bytes. Hiding that inside > read_event() makes sense. > > Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> > --- > src/py/cam/cam.py | 3 +-- > src/py/libcamera/py_main.cpp | 8 ++++++++ > test/py/unittests.py | 3 +-- > 3 files changed, 10 insertions(+), 4 deletions(-) > > diff --git a/src/py/cam/cam.py b/src/py/cam/cam.py > index e2bc78da..66df18bf 100755 > --- a/src/py/cam/cam.py > +++ b/src/py/cam/cam.py > @@ -9,7 +9,6 @@ > import argparse > import binascii > import libcamera as libcam > -import os > import sys > import traceback > > @@ -294,7 +293,7 @@ def event_handler(state): > cm = state['cm'] > contexts = state['contexts'] > > - os.read(cm.efd, 8) > + cm.read_event() > > reqs = cm.get_ready_requests() Would it make sense to read the event within get_ready_requests() ? > > diff --git a/src/py/libcamera/py_main.cpp b/src/py/libcamera/py_main.cpp > index e7066841..5d389942 100644 > --- a/src/py/libcamera/py_main.cpp > +++ b/src/py/libcamera/py_main.cpp > @@ -212,6 +212,14 @@ PYBIND11_MODULE(_libcamera, m) > return gEventfd; > }) > > + .def("read_event", [](CameraManager &) { > + uint8_t buf[8]; > + > + int ret = read(gEventfd, buf, 8); > + if (ret != 8) > + throw std::system_error(errno, std::generic_category()); > + }) > + > .def("get_ready_requests", [](CameraManager &) { > std::vector<Request *> v; > > diff --git a/test/py/unittests.py b/test/py/unittests.py > index 7dede33b..8c445bc9 100755 > --- a/test/py/unittests.py > +++ b/test/py/unittests.py > @@ -7,7 +7,6 @@ from collections import defaultdict > import errno > import gc > import libcamera as libcam > -import os > import selectors > import time > import typing > @@ -278,7 +277,7 @@ class SimpleCaptureMethods(CameraTesterBase): > while running: > events = sel.select() > for key, _ in events: > - os.read(key.fd, 8) > + cm.read_event() > > ready_reqs = cm.get_ready_requests() >
On 26/05/2022 18:27, Laurent Pinchart wrote: > Hi Tomi, > > Thank you for the patch. > > On Tue, May 24, 2022 at 02:45:57PM +0300, Tomi Valkeinen wrote: >> Add CameraManager.read_event() so that the user does not need to call >> os.read(). >> >> We use eventfd, and we must always read 8 bytes. Hiding that inside >> read_event() makes sense. >> >> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> >> --- >> src/py/cam/cam.py | 3 +-- >> src/py/libcamera/py_main.cpp | 8 ++++++++ >> test/py/unittests.py | 3 +-- >> 3 files changed, 10 insertions(+), 4 deletions(-) >> >> diff --git a/src/py/cam/cam.py b/src/py/cam/cam.py >> index e2bc78da..66df18bf 100755 >> --- a/src/py/cam/cam.py >> +++ b/src/py/cam/cam.py >> @@ -9,7 +9,6 @@ >> import argparse >> import binascii >> import libcamera as libcam >> -import os >> import sys >> import traceback >> >> @@ -294,7 +293,7 @@ def event_handler(state): >> cm = state['cm'] >> contexts = state['contexts'] >> >> - os.read(cm.efd, 8) >> + cm.read_event() >> >> reqs = cm.get_ready_requests() > > Would it make sense to read the event within get_ready_requests() ? I thought about these two functions, but this seemed the safest to me. If get_ready_requests() would do read_event(), then you could not call get_ready_requests() unless you knew there is an event waiting, or it would block. Or we could make the fd non-blocking, but I think that's usually the choice of the user, not the library. Tomi
Hi Tomi, On Fri, May 27, 2022 at 09:00:44AM +0300, Tomi Valkeinen wrote: > On 26/05/2022 18:27, Laurent Pinchart wrote: > > On Tue, May 24, 2022 at 02:45:57PM +0300, Tomi Valkeinen wrote: > >> Add CameraManager.read_event() so that the user does not need to call > >> os.read(). > >> > >> We use eventfd, and we must always read 8 bytes. Hiding that inside > >> read_event() makes sense. > >> > >> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> > >> --- > >> src/py/cam/cam.py | 3 +-- > >> src/py/libcamera/py_main.cpp | 8 ++++++++ > >> test/py/unittests.py | 3 +-- > >> 3 files changed, 10 insertions(+), 4 deletions(-) > >> > >> diff --git a/src/py/cam/cam.py b/src/py/cam/cam.py > >> index e2bc78da..66df18bf 100755 > >> --- a/src/py/cam/cam.py > >> +++ b/src/py/cam/cam.py > >> @@ -9,7 +9,6 @@ > >> import argparse > >> import binascii > >> import libcamera as libcam > >> -import os > >> import sys > >> import traceback > >> > >> @@ -294,7 +293,7 @@ def event_handler(state): > >> cm = state['cm'] > >> contexts = state['contexts'] > >> > >> - os.read(cm.efd, 8) > >> + cm.read_event() > >> > >> reqs = cm.get_ready_requests() > > > > Would it make sense to read the event within get_ready_requests() ? > > I thought about these two functions, but this seemed the safest to me. > If get_ready_requests() would do read_event(), then you could not call > get_ready_requests() unless you knew there is an event waiting, or it > would block. Or we could make the fd non-blocking, but I think that's > usually the choice of the user, not the library. Hmmm... I have a feeling we can do better, but I don't know what yet :-) It doesn't have to be done now.
diff --git a/src/py/cam/cam.py b/src/py/cam/cam.py index e2bc78da..66df18bf 100755 --- a/src/py/cam/cam.py +++ b/src/py/cam/cam.py @@ -9,7 +9,6 @@ import argparse import binascii import libcamera as libcam -import os import sys import traceback @@ -294,7 +293,7 @@ def event_handler(state): cm = state['cm'] contexts = state['contexts'] - os.read(cm.efd, 8) + cm.read_event() reqs = cm.get_ready_requests() diff --git a/src/py/libcamera/py_main.cpp b/src/py/libcamera/py_main.cpp index e7066841..5d389942 100644 --- a/src/py/libcamera/py_main.cpp +++ b/src/py/libcamera/py_main.cpp @@ -212,6 +212,14 @@ PYBIND11_MODULE(_libcamera, m) return gEventfd; }) + .def("read_event", [](CameraManager &) { + uint8_t buf[8]; + + int ret = read(gEventfd, buf, 8); + if (ret != 8) + throw std::system_error(errno, std::generic_category()); + }) + .def("get_ready_requests", [](CameraManager &) { std::vector<Request *> v; diff --git a/test/py/unittests.py b/test/py/unittests.py index 7dede33b..8c445bc9 100755 --- a/test/py/unittests.py +++ b/test/py/unittests.py @@ -7,7 +7,6 @@ from collections import defaultdict import errno import gc import libcamera as libcam -import os import selectors import time import typing @@ -278,7 +277,7 @@ class SimpleCaptureMethods(CameraTesterBase): while running: events = sel.select() for key, _ in events: - os.read(key.fd, 8) + cm.read_event() ready_reqs = cm.get_ready_requests()
Add CameraManager.read_event() so that the user does not need to call os.read(). We use eventfd, and we must always read 8 bytes. Hiding that inside read_event() makes sense. Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> --- src/py/cam/cam.py | 3 +-- src/py/libcamera/py_main.cpp | 8 ++++++++ test/py/unittests.py | 3 +-- 3 files changed, 10 insertions(+), 4 deletions(-)