3c486b98dd
Implement Linux-compatible TFD_TIMER_CANCEL_ON_SET flag for timerfd to allow applications to detect discontinuous changes to CLOCK_REALTIME. Background: According to Linux timerfd_create(2) man page, when a timerfd is created with CLOCK_REALTIME and TFD_TIMER_CANCEL_ON_SET flag is specified, the read() operation should fail with ECANCELED if the real-time clock undergoes a discontinuous change. This allows applications to detect and respond to system time changes. Implementation: 1. Add clock notifier infrastructure (clock_notifier.h/c) to notify interested parties when system time changes 2. Implement TFD_TIMER_CANCEL_ON_SET flag support in timerfd 3. Register timerfd with clock notifier when flag is set 4. Cancel timer and return ECANCELED when clock change is detected 5. Notify clock changes in: - clock_settime() - clock_initialize() - clock_timekeeping_set_wall_time() - rpmsg_rtc time synchronization Changes include: - New files: include/nuttx/clock_notifier.h, sched/clock/clock_notifier.c - Modified: fs/vfs/fs_timerfd.c to handle TFD_TIMER_CANCEL_ON_SET - Modified: clock subsystem to call notifier chain on time changes - Modified: rpmsg_rtc to notify time changes during sync Use case example: Applications using timerfd with absolute time can now detect when system time is adjusted (e.g., NTP sync, manual time change) and take appropriate action such as recalculating timeouts or updating scheduled events. Reference: https://man7.org/linux/man-pages/man2/timerfd_create.2.html Signed-off-by: dongjiuzhu1 <dongjiuzhu1@xiaomi.com> |
||
|---|---|---|
| .github | ||
| arch | ||
| audio | ||
| binfmt | ||
| boards | ||
| cmake | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| dummy | ||
| fs | ||
| graphics | ||
| include | ||
| libs | ||
| mm | ||
| net | ||
| openamp | ||
| pass1 | ||
| sched | ||
| syscall | ||
| tools | ||
| video | ||
| wireless | ||
| .asf.yaml | ||
| .codespell-ignore-lines | ||
| .codespellrc | ||
| .editorconfig | ||
| .gitignore | ||
| .gitmessage | ||
| .pre-commit-config.yaml | ||
| .yamllint | ||
| AUTHORS | ||
| CMakeLists.txt | ||
| CONTRIBUTING.md | ||
| INVIOLABLES.md | ||
| Kconfig | ||
| LICENSE | ||
| Makefile | ||
| NOTICE | ||
| README.md | ||
| ReleaseNotes | ||
Apache NuttX is a real-time operating system (RTOS) with an emphasis on standards compliance and small footprint. Scalable from 8-bit to 64-bit microcontroller environments, the primary governing standards in NuttX are POSIX and ANSI standards. Additional standard APIs from Unix and other common RTOSs (such as VxWorks) are adopted for functionality not available under these standards, or for functionality that is not appropriate for deeply-embedded environments (such as fork()).
For brevity, many parts of the documentation will refer to Apache NuttX as simply NuttX.
Getting Started
First time on NuttX? Read the Getting Started guide! If you don't have a board available, NuttX has its own simulator that you can run on terminal.
Documentation
You can find the current NuttX documentation on the Documentation Page.
Alternatively, you can build the documentation yourself by following the Documentation Build Instructions.
The old NuttX documentation is still available in the Apache wiki.
Supported Boards
NuttX supports a wide variety of platforms. See the full list on the Supported Platforms page.
Contributing
If you wish to contribute to the NuttX project, read the Contributing guidelines for information on Git usage, coding standard, workflow and the NuttX principles.
License
The code in this repository is under either the Apache 2 license, or a license compatible with the Apache 2 license. See the License Page for more information.