arch & sched: task: Fix up_exit() and nxtask_exit() for SMP

Summary:
- During repeating ostest with sabre-6quad:smp (QEMU),
  I noticed that pthread_rwlock_test sometimes stops
- Finally, I found that nxtask_exit() released a critical
  section too early before context switching which resulted in
  selecting inappropriate TCB
- This commit fixes this issue by moving nxsched_resume_scheduler()
  from nxtask_exit() to up_exit() and also removing
  spin_setbit() and spin_clrbit() from nxtask_exit()
  because the caller holds a critical section
- To be consistent with non-SMP cases, the above changes
  were done for all CPU architectures

Impact:
- This commit affects all CPU architectures regardless of SMP

Testing:
- Tested with ostest with the following configs
- sabre-6quad:smp (QEMU, dev board), sabre-6quad:nsh (QEMU)
- spresense:wifi_smp
- sim:smp, sim:ostest
- maix-bit:smp (QEMU)
- esp32-devkitc:smp (QEMU)
- lc823450-xgevk:rndis

Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>

arch/arm/src/common/arm_exit.c

@@ -150,6 +150,12 @@ void up_exit(int status)
 
   tcb = this_task();
 
+  /* Adjusts time slice for SCHED_RR & SCHED_SPORADIC cases
+   * NOTE: the API also adjusts the global IRQ control for SMP
+   */
+
+  nxsched_resume_scheduler(tcb);
+
 #ifdef CONFIG_ARCH_ADDRENV
   /* Make sure that the address environment for the previously running
    * task is closed down gracefully (data caches dump, MMU flushed) and

arch/avr/src/common/up_exit.c

@@ -165,6 +165,10 @@ void up_exit(int status)
 
   tcb = this_task();
 
+  /* Adjusts time slice for SCHED_RR & SCHED_SPORADIC cases */
+
+  nxsched_resume_scheduler(tcb);
+
 #ifdef CONFIG_ARCH_ADDRENV
   /* Make sure that the address environment for the previously running
    * task is closed down gracefully (data caches dump, MMU flushed) and

arch/hc/src/common/up_exit.c

@@ -149,6 +149,10 @@ void up_exit(int status)
 
   tcb = this_task();
 
+  /* Adjusts time slice for SCHED_RR & SCHED_SPORADIC cases */
+
+  nxsched_resume_scheduler(tcb);
+
 #ifdef CONFIG_ARCH_ADDRENV
   /* Make sure that the address environment for the previously running
    * task is closed down gracefully (data caches dump, MMU flushed) and

arch/mips/src/common/mips_exit.c

@@ -167,6 +167,12 @@ void up_exit(int status)
 
   tcb = this_task();
 
+  /* Adjusts time slice for SCHED_RR & SCHED_SPORADIC cases
+   * NOTE: the API also adjusts the global IRQ control for SMP
+   */
+
+  nxsched_resume_scheduler(tcb);
+
 #ifdef CONFIG_ARCH_ADDRENV
   /* Make sure that the address environment for the previously running
    * task is closed down gracefully (data caches dump, MMU flushed) and

arch/misoc/src/lm32/lm32_exit.c

@@ -160,6 +160,10 @@ void up_exit(int status)
 
   tcb = this_task();
 
+  /* Adjusts time slice for RR & SPORADIC cases */
+
+  nxsched_resume_scheduler(tcb);
+
 #ifdef CONFIG_ARCH_ADDRENV
   /* Make sure that the address environment for the previously running
    * task is closed down gracefully (data caches dump, MMU flushed) and

arch/misoc/src/minerva/minerva_exit.c

@@ -158,6 +158,10 @@ void up_exit(int status)
 
   tcb = this_task();
 
+  /* Adjusts time slice for SCHED_RR & SCHED_SPORADIC cases */
+
+  nxsched_resume_scheduler(tcb);
+
 #ifdef CONFIG_ARCH_ADDRENV
   /* Make sure that the address environment for the previously running task
    * is closed down gracefully (data caches dump, MMU flushed) and set up the

arch/or1k/src/common/up_exit.c

@@ -165,6 +165,10 @@ void up_exit(int status)
 
   tcb = this_task();
 
+  /* Adjusts time slice for SCHED_RR & SCHED_SPORADIC cases */
+
+  nxsched_resume_scheduler(tcb);
+
 #ifdef CONFIG_ARCH_ADDRENV
   /* Make sure that the address environment for the previously running
    * task is closed down gracefully (data caches dump, MMU flushed) and

arch/renesas/src/common/up_exit.c

@@ -149,6 +149,10 @@ void up_exit(int status)
 
   tcb = this_task();
 
+  /* Adjusts time slice for RR & SPORADIC cases */
+
+  nxsched_resume_scheduler(tcb);
+
 #ifdef CONFIG_ARCH_ADDRENV
   /* Make sure that the address environment for the previously running
    * task is closed down gracefully (data caches dump, MMU flushed) and

arch/risc-v/src/common/riscv_exit.c

@@ -167,6 +167,12 @@ void up_exit(int status)
 
   tcb = this_task();
 
+  /* Adjusts time slice for SCHED_RR & SCHED_SPORADIC cases
+   * NOTE: the API also adjusts the global IRQ control for SMP
+   */
+
+  nxsched_resume_scheduler(tcb);
+
 #ifdef CONFIG_ARCH_ADDRENV
   /* Make sure that the address environment for the previously running
    * task is closed down gracefully (data caches dump, MMU flushed) and

arch/sim/src/sim/up_exit.c

@@ -86,6 +86,12 @@ void up_exit(int status)
   tcb = this_task();
   sinfo("New Active Task TCB=%p\n", tcb);
 
+  /* Adjusts time slice for SCHED_RR & SCHED_SPORADIC cases
+   * NOTE: the API also adjusts the global IRQ control for SMP
+   */
+
+  nxsched_resume_scheduler(tcb);
+
   /* The way that we handle signals in the simulation is kind of
    * a kludge.  This would be unsafe in a truly multi-threaded, interrupt
    * driven environment.

arch/x86/src/common/up_exit.c

@@ -149,6 +149,12 @@ void up_exit(int status)
 
   tcb = this_task();
 
+  /* Adjusts time slice for SCHED_RR & SCHED_SPORADIC cases
+   * NOTE: the API also adjusts the global IRQ control for SMP
+   */
+
+  nxsched_resume_scheduler(tcb);
+
 #ifdef CONFIG_ARCH_ADDRENV
   /* Make sure that the address environment for the previously running
    * task is closed down gracefully (data caches dump, MMU flushed) and

arch/x86_64/src/common/up_exit.c

@@ -153,6 +153,12 @@ void up_exit(int status)
 
   tcb = this_task();
 
+  /* Adjusts time slice for SCHED_RR & SCHED_SPORADIC cases
+   * NOTE: the API also adjusts the global IRQ control for SMP
+   */
+
+  nxsched_resume_scheduler(tcb);
+
   /* Context switch, rearrange MMU */
 
   up_restore_auxstate(tcb);

arch/xtensa/src/common/xtensa_exit.c

@@ -172,6 +172,12 @@ void up_exit(int status)
 
   tcb = this_task();
 
+  /* Adjusts time slice for SCHED_RR & SCHED_SPORADIC cases
+   * NOTE: the API also adjusts the global IRQ control for SMP
+   */
+
+  nxsched_resume_scheduler(tcb);
+
 #if XCHAL_CP_NUM > 0
   /* Set up the co-processor state for the newly started thread. */
 

arch/z16/src/common/z16_exit.c

@@ -150,6 +150,10 @@ void up_exit(int status)
   tcb = this_task();
   sinfo("New Active Task TCB=%p\n", tcb);
 
+  /* Adjusts time slice for SCHED_RR & SCHED_SPORADIC cases */
+
+  nxsched_resume_scheduler(tcb);
+
   /* Then switch contexts */
 
   RESTORE_USERCONTEXT(tcb);

arch/z80/src/common/z80_exit.c

@@ -152,6 +152,10 @@ void up_exit(int status)
   tcb = this_task();
   sinfo("New Active Task TCB=%p\n", tcb);
 
+  /* Adjusts time slice for SCHED_RR & SCHED_SPORADIC cases */
+
+  nxsched_resume_scheduler(tcb);
+
 #ifdef CONFIG_ARCH_ADDRENV
   /* Make sure that the address environment for the previously running
    * task is closed down gracefully (data caches dump, MMU flushed) and

sched/task/task_exit.c

@@ -119,12 +119,12 @@ int nxtask_exit(void)
   rtcb = this_task();
 #endif
 
-  /* Because clearing the global IRQ control in nxsched_remove_readytorun()
-   * was moved to nxsched_resume_scheduler(). So call the API here.
+  /* NOTE: nxsched_resume_scheduler() was moved to up_exit()
+   * because the global IRQ control for SMP should be deferred until
+   * context switching, otherwise, the context switching would be done
+   * without a critical section
    */
 
-  nxsched_resume_scheduler(rtcb);
-
   /* We are now in a bad state -- the head of the ready to run task list
    * does not correspond to the thread that is running.  Disabling pre-
    * emption on this TCB and marking the new ready-to-run task as not
@@ -162,19 +162,6 @@ int nxtask_exit(void)
    * To prevent from aquiring, increment rtcb->irqcount here.
    */
 
-  if (rtcb->irqcount == 0)
-    {
-      /* NOTE: Need to aquire g_cpu_irqlock here again before
-       * calling spin_setbit() becauses it was released in
-       * the above nxsched_resume_scheduler()
-       */
-
-      DEBUGVERIFY(irq_waitlock(this_cpu()));
-
-      spin_setbit(&g_cpu_irqset, this_cpu(), &g_cpu_irqsetlock,
-                  &g_cpu_irqlock);
-    }
-
   rtcb->irqcount++;
 #endif
 
@@ -182,12 +169,6 @@ int nxtask_exit(void)
 
 #ifdef CONFIG_SMP
   rtcb->irqcount--;
-
-  if (rtcb->irqcount == 0)
-    {
-      spin_clrbit(&g_cpu_irqset, this_cpu(), &g_cpu_irqsetlock,
-                  &g_cpu_irqlock);
-    }
 #endif
 
   rtcb->task_state = TSTATE_TASK_RUNNING;