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>
The delete flag is not synchronized with the life cycle of the group,
if the flag set before waitpid(), the tcb will be mistakenly deleted
by group_del_waiter(), use-after-free will happen.
Regression by:
| commit 29e50ffa73 (origin/master, origin/HEAD)
| Author: chao an <anchao@lixiang.com>
| Date: Mon Mar 4 09:19:27 2024 +0800
|
| sched/group: move task group into task_tcb_s to improve performance
|
| 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>
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>
Skip the child wait if here is only self in member list,
since the members of the task group should be 1 if task exit.
Fix Regression issue that the task could not terminate normally.
Signed-off-by: chao an <anchao@lixiang.com>
Change the type of task group member to single list chain to
avoid accessing the memory allocator to improve the performance
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>
Task group could find from process id, replace group_findbypid to
task_getgroup to simplify the search logic
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.
Add support for static tcb, applications in some special case can
initialize system resources in advance through static tcb.
| static struct task_tcb_s g_tcb;
|
| memset(&g_tcb, 0, sizeof(struct task_tcb_s));
| g_tcb.cmn.flags = TCB_FLAG_TTYPE_KERNEL;
| nxtask_init(&g_tcb, "PTCB", 101, NULL, 1024, ptcb_task, NULL, NULL, NULL);
|
| ...
| nxtask_activate(&g_tcb.cmn);
Signed-off-by: chao an <anchao@lixiang.com>
Recursive:
25 0x44000e5a in up_cpu_paused (cpu=cpu@entry=1) at armv7-a/arm_cpupause.c:120
26 0x440032f2 in enter_critical_section () at irq/irq_csection.c:275
27 0x44006f24 in nxsched_process_taskload_ticks (tcb=tcb@entry=0x442ba638 <g_idletcb+256>, ticks=0) at sched/sched_cpuload.c:104
28 0x44007310 in nxsched_suspend_critmon (tcb=tcb@entry=0x442ba638 <g_idletcb+256>) at sched/sched_critmonitor.c:303
29 0x44006ef0 in nxsched_suspend_scheduler (tcb=tcb@entry=0x442ba638 <g_idletcb+256>) at sched/sched_suspendscheduler.c:78
30 0x44000e5a in up_cpu_paused (cpu=cpu@entry=1) at armv7-a/arm_cpupause.c:120
31 0x440032f2 in enter_critical_section () at irq/irq_csection.c:275
32 0x44000f1a in arm_pause_handler (irq=<optimized out>, context=<optimized out>, arg=<optimized out>) at armv7-a/arm_cpupause.c:216
33 0x44002ffe in irq_dispatch (irq=irq@entry=2, context=context@entry=0x4449f6b8 <g_cpu1_idlestack+1720>) at irq/irq_dispatch.c:146
34 0x44001612 in arm_doirq (irq=2, irq@entry=0, regs=0x4449f6b8 <g_cpu1_idlestack+1720>) at armv7-a/arm_doirq.c:72
35 0x44000940 in arm_decodeirq (regs=<optimized out>) at armv7-a/arm_gicv2.c:403
36 0x440000b4 in arm_vectorirq () at armv7-a/arm_vectors.S:236
Signed-off-by: ligd <liguiding1@xiaomi.com>
cpu0 thread0: cpu1:
sched_yield()
nxsched_set_priority()
nxsched_running_setpriority()
nxsched_reprioritize_rtr()
nxsched_add_readytorun()
up_cpu_pause()
IRQ enter
arm64_pause_handler()
enter_critical_section() begin
up_cpu_paused() pick thread0
arm64_restorestate() set thread0 tcb->xcp.regs to CURRENT_REGS
up_switch_context()
thread0 -> thread1
arm64_syscall()
case SYS_switch_context
change thread0 tcb->xcp.regs
restore_critical_section()
enter_critical_section() done
leave_critical_section()
IRQ leave with restore CURRENT_REGS
ERROR !!!
Reason:
As descript above, cpu0 swith task: thread0 -> thread1, and the
syscall() execute slowly, this time cpu1 pick thread0 to run at
up_cpu_paused(). Then cpu0 syscall execute, cpu1 IRQ leave error.
Resolve:
Move arm64_restorestate() after enter_critical_section() done
This is a continued fix with:
https://github.com/apache/nuttx/pull/6833
Signed-off-by: ligd <liguiding1@xiaomi.com>
These variables will trigger variable 'ret' set but not used warnings due to different configurations.
Signed-off-by: yinshengkai <yinshengkai@xiaomi.com>
