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>
waitpid() cannot be used in kernel mode unless SCHED_HAVE_PARENT is
selected -> add dependency if BUILD_KERNEL is selected.
Why? Because without SCHED_HAVE_PARENT waitpid() works in a non-standard
way, meaning it does not use SIGCHLD to wake the parent, as it should.
Also, returning the child status via stat_loc corrupts memory as stat_loc
points to the parent's address environment:
pid_t nxsched_waitpid(pid_t pid, int *stat_loc, int options)
{
...
group->tg_statloc = stat_loc;
...
}
And later when the status is returned, the child writes to tg_statloc,
which points to the parent's address environment -> random memory
corruption:
static inline void nxtask_exitwakeup(FAR struct tcb_s *tcb, int status)
{
...
if (group->tg_statloc != NULL)
{
*group->tg_statloc = status << 8;
}
...
}
This log appears for NSH internal commands in KERNEL build and
duplicates a lot with task_spawn: log. So drop it to make the
DEBUG_SCHED_INFO logging more readable.
Signed-off-by: Yanfeng Liu <yfliu2008@qq.com>
we removed "select SCHED_RESUMESCHEDULER",
As SCHED_RESUMESCHEDULER is not a necessary feature in SMP,
turning it on by default may affect performance.
Signed-off-by: hujun5 <hujun5@xiaomi.com>
test:
We can use qemu for testing.
compiling
make distclean -j20; ./tools/configure.sh -l qemu-armv8a:nsh_smp ;make -j20 running
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
We have also tested this patch on other ARM hardware platforms.
Signed-off-by: hujun5 <hujun5@xiaomi.com>
purpose:
1 sched_lock is very time-consuming, and reducing its invocations can improve performance.
2 sched_lock is prone to misuse, and narrowing its scope of use is to prevent people from referencing incorrect code and using it
test:
We can use qemu for testing.
compiling
make distclean -j20; ./tools/configure.sh -l qemu-armv8a:nsh_smp ;make -j20
running
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
We have also tested this patch on other ARM hardware platforms.
Signed-off-by: hujun5 <hujun5@xiaomi.com>
purpose:
1 sched_lock is very time-consuming, and reducing its invocations can improve performance.
2 sched_lock is prone to misuse, and narrowing its scope of use is to prevent people from referencing incorrect code and using it
test:
We can use qemu for testing.
compiling
make distclean -j20; ./tools/configure.sh -l qemu-armv8a:nsh_smp ;make -j20
running
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
We have also tested this patch on other ARM hardware platforms.
Signed-off-by: hujun5 <hujun5@xiaomi.com>
1. The critical section does not prevent task scheduling
2. If the critical section is in sched_lock, there is no need to check,
scheduling is not going to happen
3. If sched_lock is in the critical section, sched_unlock will also
trigger scheduling without waiting for the exit of the critical section
4. After exiting the critical section, if there is an interrupt,
the scheduling will be automatically triggered
Signed-off-by: hujun5 <hujun5@xiaomi.com>
In order to ensure the detached thread obtain the correct return
value from pthread_join()/pthread_cancel(), the detached thread
will create joininfo to save the detached status after thread
destroyed. If there are too many of detached threads in the
process group, the joininfo will consume too much memory.
This is not friendly to embedded MCU devices.
This commit keep the semantics as #11898 was introduced,
will no longer save joininfo for detached threads to avoid wasting memory.
Signed-off-by: chao an <anchao@lixiang.com>
Prior to this commit, doswitch is returned uninitialized if
(task_state == TSTATE_TASK_ASSIGNED || task_state == TSTATE_TASK_RUNNING)
&& no context switch occurs
&& (cpu == me).
Signed-off-by: Mingjie Shen <shen497@purdue.edu>
In SMP mode, up_cpu_index()/this_cpu() are the same, both return the index of the physical core.
In AMP mode, up_cpu_index() will return the index of the physical core, and this_cpu() will always return 0
| #ifdef CONFIG_SMP
| # define this_cpu() up_cpu_index()
| #elif defined(CONFIG_AMP)
| # define this_cpu() (0)
| #else
| # define this_cpu() (0)
| #endif
Signed-off-by: chao an <anchao@lixiang.com>
The overhead of spinlok is less than mutext (mutex need to call
enter_critical section.)
After this patch, `down_write_trylock` and `down_read_trylock` can be
use in interrupt context.
The instruction is protected with mutex only one instruction so using
spinlock is better.
Signed-off-by: TaiJu Wu <tjwu1217@gmail.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>