508c5889d7
reason: 1 To improve efficiency, we mimic Linux's behavior where preemption disabling is only applicable to the current CPU and does not affect other CPUs. 2 In the future, we will implement "spinlock+sched_lock", and use it extensively. Under such circumstances, if preemption is still globally disabled, it will seriously impact the scheduling efficiency. 3 We have removed g_cpu_lockset and used irqcount in order to eliminate the dependency of schedlock on critical sections in the future, simplify the logic, and further enhance the performance of sched_lock. 4 We set lockcount to 1 in order to lock scheduling on all CPUs during startup, without the need to provide additional functions to disable scheduling on other CPUs. 5 Cpu1~n must wait for cpu0 to enter the idle state before enabling scheduling because it prevents CPUs1~n from competing with cpu0 for the memory manager mutex, which could cause the cpu0 idle task to enter a wait state and trigger an assert. size nuttx before: text data bss dec hex filename 265396 51057 63646 380099 5ccc3 nuttx after: text data bss dec hex filename 265184 51057 63642 379883 5cbeb nuttx size -216 Configuring NuttX and compile: $ ./tools/configure.sh -l qemu-armv8a:nsh_smp $ make Running with qemu $ qemu-system-aarch64 -cpu cortex-a53 -smp 4 -nographic \ -machine virt,virtualization=on,gic-version=3 \ -net none -chardev stdio,id=con,mux=on -serial chardev:con \ -mon chardev=con,mode=readline -kernel ./nuttx Signed-off-by: hujun5 <hujun5@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 | ||
.gitignore | ||
.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.