reason:
We can utilize percpu storage to hold information about the
current running task. If we intend to implement this feature, we would
need to define two macros that help us manage this percpu information
effectively.
up_this_task: This macro is designed to read the contents of the percpu
register to retrieve information about the current
running task.This allows us to quickly access
task-specific data without having to disable interrupts,
access global variables and obtain the current cpu index.
up_update_task: This macro is responsible for updating the contents of
the percpu register.It is typically called during
initialization or when a context switch occurs to ensure
that the percpu register reflects the information of the
newly running task.
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>
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>
reason:
Currently, if we need to schedule a task to another CPU, we have to completely halt the other CPU,
manipulate the scheduling linked list, and then resume the operation of that CPU. This process is both time-consuming and unnecessary.
During this process, both the current CPU and the target CPU are inevitably subjected to busyloop.
The improved strategy is to simply send a cross-core interrupt to the target CPU.
The current CPU continues to run while the target CPU responds to the interrupt, eliminating the certainty of a busyloop occurring.
Signed-off-by: hujun5 <hujun5@xiaomi.com>
Most tools used for compliance and SBOM generation use SPDX identifiers
This change brings us a step closer to an easy SBOM generation.
Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
The file descriptors of kernel threads should be clean and should
not be generated based on user threads. Instead, an idle thread
hould be chosen.
Signed-off-by: dongjiuzhu1 <dongjiuzhu1@xiaomi.com>
Kthreads can share the group data so that to reduce overheads.
This implements shared kthread group via:
- use `tcb_s` instead of `task_tcb_s` for kthreads
- use `g_kthread_group` when creating kthreads
- use stackargs to start tasks and kthreads
see pull/12320 for test logs.
Signed-off-by: Yanfeng Liu <yfliu2008@qq.com>
sched implementation not depends on macro abstraction, so revert below commit:
This reverts commit 4e62d0005a
This reverts commit 0f0c370520
This reverts commit ad0efd04ee
Signed-off-by: chao an <anchao@lixiang.com>
1. add support to join main task
| static pthread_t self;
|
| static void *join_task(void *arg)
| {
| int ret;
| ret = pthread_join(self, NULL); <--- /* Fix Task could not be joined */
| return NULL;
| }
|
| int main(int argc, char *argv[])
| {
| pthread_t thread;
|
| self = pthread_self();
|
| pthread_create(&thread, NULL, join_task, NULL);
| sleep(1);
|
| pthread_exit(NULL);
| return 0;
| }
2. Detach active thread will not alloc for additional join, just update the task flag.
3. Remove the return value waiting lock logic (data_sem),
the return value will be stored in the waiting tcb.
4. Revise the return value of pthread_join(), consistent with linux
e.g:
Joining a detached and canceled thread should return EINVAL, not ESRCH
https://pubs.opengroup.org/onlinepubs/009695399/functions/pthread_join.html
[EINVAL]
The value specified by thread does not refer to a joinable thread.
NOTE:
This PR will not increase stack usage, but struct tcb_s will increase 32 bytes.
Signed-off-by: chao an <anchao@lixiang.com>
move task group into task_tcb_s to avoid access allocator to improve performance
for Task Termination, the time consumption will be reduced ~2us (Tricore TC397 300MHZ):
15.97(us) -> 13.55(us)
Signed-off-by: chao an <anchao@lixiang.com>
The maximum startup parameters have been checked accordingly in nxtask_setup_stackargs(),
let us save argument counter to avoid limit check.
Signed-off-by: chao an <anchao@lixiang.com>
Current `CONFIG_PAGING` refers to an experimental implementation
to enable embedded MCUs with some limited RAM space to execute
large programs from some non-random access media.
On-demand paging should be implemented for the kernel mode with
address environment implementation enabled.
These variables will trigger variable 'ret' set but not used warnings due to different configurations.
Signed-off-by: yinshengkai <yinshengkai@xiaomi.com>
Usually the startup script is placed under /etc. The contents of the etc directory
are compiled and linked with Nuttx binary in the form of romfs. After startup,
it will be mounted by Nsh.
etc is generated by the different boards, that use genromfs and xxd tools to generate
and compile it into the Nuttx, for example: boards/arm/at32/at32f437-mini/tool/mkromfs.sh
The more common method is etc image generated from the content in the corresponding
board/arch/board/board/src/etc directory, and added by Makefile for example:
boards/sim/sim/sim/src/etc.
But in kernel/protected mode, Nuttx kernel and apps are run in different privileged/
non-privileged mode or the isolated binarys, so as that nsh should use syscall to
access Nuttx kernel by exported API. In this scenario, nsh can not mount the etc image
content, because that is generated in board and as a part of Nuttx kernel.
changes:
- move etc romfs mount from nsh to Nuttx, but keep the script to parse and execute.
- move and rename the related CONFIG, move customized nsh_romfsimg.h to etc_romfs.c
in boards, and no need declaration for romfs_img/romfs_img_len.
This commit changes and updates all configurations in Nuttx arch/board as much as possible,
but if any missing, please refer to the following simple guide:
- rename CONFIG_NSH_ROMFSETC to CONFIG_ETC_ROMFS, and delete CONFIG_NSH_ARCHROMFS in defconfig
- rename the etc romfs mount configs, for example CONFIG_NSH_FATDEVNO to CONFIG_ETC_FATDEVNO
- move customized nsh_romfsimg.h to etc_romfs.c in board/arch/board/board/src and no need
declaration for romfs_img/romfs_img_len.
- delete default nsh_romfsimg.h, if ROMFSETC is enabled, should generate and compile etc_romfs.c
in board/arch/board/board/src.
Signed-off-by: fangxinyong <fangxinyong@xiaomi.com>
Usage:
1. CONFIG_FS_PROCFS_MAX_STACK_RECORD > 0, such as 32,
2. add '-finstrument-functions' to CFLAGS for What you want to check
stack.
3. mount porcfs
4. cat /proc/<pid>/stack will print backtace & size
Signed-off-by: anjiahao <anjiahao@xiaomi.com>
The task files should consult the "spawn action" and "O_CLOEXEC flags"
to determine further whether the file should be duplicated.
This PR will further optimize file list duplicating to avoid the performance
regression caused by additional file operations.
Signed-off-by: chao an <anchao@xiaomi.com>
This moves task / thread cancel point logic from the NuttX kernel into
libc, while the data needed by the cancel point logic is moved to TLS.
The change is an enabler to move user-space APIs to libc as well, for
a coherent user/kernel separation.
core0 may write the data used by other cpu, this will cause cache inconsistency.
so need fulsh dcache before start other cpus.
Signed-off-by: zhangyuan21 <zhangyuan21@xiaomi.com>
We can use the driver in nuttx to download
files with debugger
Signed-off-by: anjiahao <anjiahao@xiaomi.com>
Signed-off-by: chao an <anchao@xiaomi.com>
1. Update all CMakeLists.txt to adapt to new layout
2. Fix cmake build break
3. Update all new file license
4. Fully compatible with current compilation environment(use configure.sh or cmake as you choose)
------------------
How to test
From within nuttx/. Configure:
cmake -B build -DBOARD_CONFIG=sim/nsh -GNinja
cmake -B build -DBOARD_CONFIG=sim:nsh -GNinja
cmake -B build -DBOARD_CONFIG=sabre-6quad/smp -GNinja
cmake -B build -DBOARD_CONFIG=lm3s6965-ek/qemu-flat -GNinja
(or full path in custom board) :
cmake -B build -DBOARD_CONFIG=$PWD/boards/sim/sim/sim/configs/nsh -GNinja
This uses ninja generator (install with sudo apt install ninja-build). To build:
$ cmake --build build
menuconfig:
$ cmake --build build -t menuconfig
--------------------------
2. cmake/build: reformat the cmake style by cmake-format
https://github.com/cheshirekow/cmake_format
$ pip install cmakelang
$ for i in `find -name CMakeLists.txt`;do cmake-format $i -o $i;done
$ for i in `find -name *\.cmake`;do cmake-format $i -o $i;done
Co-authored-by: Matias N <matias@protobits.dev>
Signed-off-by: chao an <anchao@xiaomi.com>
This adds functionality to map pages dynamically into kernel virtual
memory. This allows implementing I/O remap for example, which is a useful
(future) feature.
Now, the first target is to support mapping user pages for the kernel.
Why? There are some userspace structures that might be needed when the
userspace process is not running. Semaphores are one such example. Signals
and the WDT timeout both need access to the user semaphore to work
properly. Even though for this only obtaining the kernel addressable
page pool virtual address is needed, for completeness a procedure is
provided to map several pages.
Set the Default CPU bits. The way to use the unset CPU is to call the
sched_setaffinity function to bind a task to the CPU. bit0 means CPU0.
Signed-off-by: zhangyuan21 <zhangyuan21@xiaomi.com>
The spawn proxy thread is a special existence in NuttX, usually some developers
spend a lot of time on stack overflow of spawn proxy thread:
https://github.com/apache/nuttx/issues/9046https://github.com/apache/nuttx/pull/9081
In order to avoid similar issues, this PR will remove spawn proxy thread to simplify
the process of task/posix_spawn().
1. Postpone the related processing of spawn file actions until after task_init()
2. Delete the temporary thread of spawn proxy and related global variables
Signed-off-by: chao an <anchao@xiaomi.com>
because if we pass predefined environment variables table explicitly,
the environment variables created by the board code will be lost.
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
hujun5