Search found 8 matches

by jdoubleu
Thu Feb 09, 2023 6:17 pm
Forum: ESP-IDF
Topic: esp_execute_shared_stack_function thread safety
Replies: 2
Views: 1483

Re: esp_execute_shared_stack_function thread safety

Thanks for the quick reply! Please note the open issue on GitHub, which is also affected by the function, but not related to my issue: https://github.com/espressif/esp-idf/issues/10414. While I'm at it: it would be really nice if I could pass void* arg to esp_execute_shared_stack_function, so that m...
by jdoubleu
Wed Feb 08, 2023 3:52 pm
Forum: ESP-IDF
Topic: esp_execute_shared_stack_function thread safety
Replies: 2
Views: 1483

esp_execute_shared_stack_function thread safety

I was wondering whether I could call esp_execute_shared_stack_function from multiple tasks. Looking at the implementation, the function doesn't seem to be thread safe. Mainly because it uses global static variables (e.g. xtensa_shared_stack_callback ). Although I have to pass a mutex, this is only u...
by jdoubleu
Mon Oct 11, 2021 4:38 pm
Forum: ESP-IDF
Topic: Why does gcc not make use of special OP codes
Replies: 3
Views: 3423

Re: Why does gcc not make use of special OP codes

https://github.com/espressif/esp-idf/blob/3e370c4296247b349aa3b9a0076c05b9946d47dc/components/xtensa/esp32/include/xtensa/config/core.h#L1404-L1413 Interesting. The zero-overhead loop is already very constrained in terms of application. There are only few cases where this loop can be used anyways.
by jdoubleu
Mon Oct 11, 2021 4:15 pm
Forum: ESP-IDF
Topic: Why does gcc not make use of special OP codes
Replies: 3
Views: 3423

Re: Why does gcc not make use of special OP codes

As it turns out, the compiler indeed uses these special OP codes and outputs them in at least -O2 mode. It just so appears that they're not being used in most of my functions, probably because the compiler found a better way? The following C code: static int my_min(int a, int b) { return a < b ? a :...
by jdoubleu
Thu Sep 30, 2021 9:52 am
Forum: ESP-IDF
Topic: Confused on how to embed files and what directory to place them
Replies: 2
Views: 6200

Re: Confused on how to embed files and what directory to place them

First of all, you don't need to use component.mk if you're using the CMake build system. You can find the documentation about embedding files here: https://docs.espressif.com/projects/esp-idf/en/stable/esp32/api-guides/build-system.html#embedding-binary-data Make sure you following the naming rules/...
by jdoubleu
Thu Sep 30, 2021 8:21 am
Forum: ESP-IDF
Topic: Does the ESP32 have SIMD-like instructions?
Replies: 12
Views: 13665

Re: Does the ESP32 have SIMD-like instructions?

As far as I know there aren't any, besides these already mentioned above (e.g. MUL16). If you would like to find out what Xtensa features are enabled, the overlaying headers for binutils could be helpful: https://github.com/espressif/xtensa-overlays/blob/master/xtensa_esp32/binutils/include/xtensa-c...
by jdoubleu
Wed Sep 29, 2021 4:46 pm
Forum: ESP-IDF
Topic: Why does gcc not make use of special OP codes
Replies: 3
Views: 3423

Why does gcc not make use of special OP codes

I was wondering why gcc wouldn't use specialized OP codes from the xtensa instruction set architecture (ISA). I'm using the ESP32-WROVER-B board, which itself uses the Xtensa LX6 microprocessor. From their Overview Handbook, I learned that the Xtensa LX processor family supports some specialized ext...
by jdoubleu
Wed Sep 29, 2021 4:10 pm
Forum: ESP-IDF
Topic: Https request / Content-length = 0
Replies: 3
Views: 3051

Re: Https request / Content-length = 0

What status code do you get back from the API on the first call? Is it a "401 Unauthorized"? I assume curl automatically re-tries your request if you didn't provide any information about client certificate authentication, like your web browser, which prompted you first. I found this function in the ...