From d0ae4f40f71e0e3f2d95fc521f0b6db43414fbe2 Mon Sep 17 00:00:00 2001
From: YAMAMOTO Takashi <yamamoto@midokura.com>
Date: Fri, 27 Sep 2024 13:43:54 +0900
Subject: [PATCH] Revert "arch: change nxsched_suspend/resume_scheduler()
 called position"

This reverts commit 35c8c80a00a99ff0e19d51eaa74165bd830a36f8.

because it caused a regression.
with esp32-devkitc:knsh, nsh prompt on serial console doesn't seem to
accept any input.
---
 arch/arm/src/arm/arm_doirq.c                  |  5 ---
 arch/arm/src/armv6-m/arm_doirq.c              |  5 ---
 arch/arm/src/armv7-a/arm_doirq.c              |  5 ---
 arch/arm/src/armv7-a/arm_syscall.c            | 10 ++----
 arch/arm/src/armv7-m/arm_doirq.c              |  5 ---
 arch/arm/src/armv7-r/arm_doirq.c              |  5 ---
 arch/arm/src/armv7-r/arm_syscall.c            |  8 +----
 arch/arm/src/armv8-m/arm_doirq.c              |  5 ---
 arch/arm/src/armv8-r/arm_doirq.c              |  8 +----
 arch/arm/src/armv8-r/arm_syscall.c            |  8 +----
 arch/arm/src/common/arm_switchcontext.c       | 19 +++++++++++-
 arch/arm64/src/common/arm64_doirq.c           |  5 ---
 arch/arm64/src/common/arm64_switchcontext.c   | 19 +++++++++++-
 arch/arm64/src/common/arm64_syscall.c         | 10 ++----
 arch/ceva/src/common/ceva_doirq.c             |  5 ---
 arch/ceva/src/common/ceva_switchcontext.c     | 12 +++++++
 arch/risc-v/src/common/riscv_doirq.c          |  5 ---
 arch/risc-v/src/common/riscv_switchcontext.c  | 12 +++++++
 arch/x86/src/qemu/qemu_handlers.c             |  5 ---
 arch/x86_64/src/common/x86_64_switchcontext.c | 21 ++++++++-----
 arch/x86_64/src/intel64/intel64_handlers.c    |  5 ---
 arch/xtensa/src/common/xtensa_irqdispatch.c   |  5 ---
 arch/xtensa/src/common/xtensa_switchcontext.c | 31 ++++++++++++++++++-
 23 files changed, 110 insertions(+), 108 deletions(-)

diff --git a/arch/arm/src/arm/arm_doirq.c b/arch/arm/src/arm/arm_doirq.c
index 55e056a8ee2ac..6cc7da46bdef2 100644
--- a/arch/arm/src/arm/arm_doirq.c
+++ b/arch/arm/src/arm/arm_doirq.c
@@ -103,11 +103,6 @@ uint32_t *arm_doirq(int irq, uint32_t *regs)
       addrenv_switch(NULL);
 #endif
 
-      /* Update scheduler parameters */
-
-      nxsched_suspend_scheduler(g_running_tasks[this_cpu()]);
-      nxsched_resume_scheduler(tcb);
-
       /* Record the new "running" task when context switch occurred.
        * g_running_tasks[] is only used by assertion logic for reporting
        * crashes.
diff --git a/arch/arm/src/armv6-m/arm_doirq.c b/arch/arm/src/armv6-m/arm_doirq.c
index 3065a4f4dad09..566d9390a00e3 100644
--- a/arch/arm/src/armv6-m/arm_doirq.c
+++ b/arch/arm/src/armv6-m/arm_doirq.c
@@ -75,11 +75,6 @@ uint32_t *arm_doirq(int irq, uint32_t *regs)
 
       if (regs != tcb->xcp.regs)
         {
-          /* Update scheduler parameters */
-
-          nxsched_suspend_scheduler(g_running_tasks[this_cpu()]);
-          nxsched_resume_scheduler(tcb);
-
           /* Record the new "running" task when context switch occurred.
            * g_running_tasks[] is only used by assertion logic for reporting
            * crashes.
diff --git a/arch/arm/src/armv7-a/arm_doirq.c b/arch/arm/src/armv7-a/arm_doirq.c
index 97feb8b8f61f6..460bb9a6c478a 100644
--- a/arch/arm/src/armv7-a/arm_doirq.c
+++ b/arch/arm/src/armv7-a/arm_doirq.c
@@ -98,11 +98,6 @@ uint32_t *arm_doirq(int irq, uint32_t *regs)
       addrenv_switch(NULL);
 #endif
 
-      /* Update scheduler parameters */
-
-      nxsched_suspend_scheduler(g_running_tasks[this_cpu()]);
-      nxsched_resume_scheduler(tcb);
-
       /* Record the new "running" task when context switch occurred.
        * g_running_tasks[] is only used by assertion logic for reporting
        * crashes.
diff --git a/arch/arm/src/armv7-a/arm_syscall.c b/arch/arm/src/armv7-a/arm_syscall.c
index e2791e1817ceb..9a8df57bdd8dd 100644
--- a/arch/arm/src/armv7-a/arm_syscall.c
+++ b/arch/arm/src/armv7-a/arm_syscall.c
@@ -579,18 +579,12 @@ uint32_t *arm_syscall(uint32_t *regs)
       addrenv_switch(NULL);
 #endif
 
-      cpu = this_cpu();
-      tcb = current_task(cpu);
-
-      /* Update scheduler parameters */
-
-      nxsched_suspend_scheduler(g_running_tasks[cpu]);
-      nxsched_resume_scheduler(tcb);
-
       /* Record the new "running" task.  g_running_tasks[] is only used by
        * assertion logic for reporting crashes.
        */
 
+      cpu = this_cpu();
+      tcb = current_task(cpu);
       g_running_tasks[cpu] = tcb;
 
       /* Restore the cpu lock */
diff --git a/arch/arm/src/armv7-m/arm_doirq.c b/arch/arm/src/armv7-m/arm_doirq.c
index 5c31de792ecf0..c1370659c9e74 100644
--- a/arch/arm/src/armv7-m/arm_doirq.c
+++ b/arch/arm/src/armv7-m/arm_doirq.c
@@ -75,11 +75,6 @@ uint32_t *arm_doirq(int irq, uint32_t *regs)
 
       if (regs != tcb->xcp.regs)
         {
-          /* Update scheduler parameters */
-
-          nxsched_suspend_scheduler(g_running_tasks[this_cpu()]);
-          nxsched_resume_scheduler(tcb);
-
           /* Record the new "running" task when context switch occurred.
            * g_running_tasks[] is only used by assertion logic for reporting
            * crashes.
diff --git a/arch/arm/src/armv7-r/arm_doirq.c b/arch/arm/src/armv7-r/arm_doirq.c
index dae25dd47e852..7b08a7dd56326 100644
--- a/arch/arm/src/armv7-r/arm_doirq.c
+++ b/arch/arm/src/armv7-r/arm_doirq.c
@@ -77,11 +77,6 @@ uint32_t *arm_doirq(int irq, uint32_t *regs)
 
   if (regs != tcb->xcp.regs)
     {
-      /* Update scheduler parameters */
-
-      nxsched_suspend_scheduler(g_running_tasks[this_cpu()]);
-      nxsched_resume_scheduler(tcb);
-
       /* Record the new "running" task when context switch occurred.
        * g_running_tasks[] is only used by assertion logic for reporting
        * crashes.
diff --git a/arch/arm/src/armv7-r/arm_syscall.c b/arch/arm/src/armv7-r/arm_syscall.c
index d7dcdbcfe9728..66d2181618478 100644
--- a/arch/arm/src/armv7-r/arm_syscall.c
+++ b/arch/arm/src/armv7-r/arm_syscall.c
@@ -566,17 +566,11 @@ uint32_t *arm_syscall(uint32_t *regs)
 
   if (regs != tcb->xcp.regs)
     {
-      cpu = this_cpu();
-
-      /* Update scheduler parameters */
-
-      nxsched_suspend_scheduler(g_running_tasks[cpu]);
-      nxsched_resume_scheduler(tcb);
-
       /* Record the new "running" task.  g_running_tasks[] is only used by
        * assertion logic for reporting crashes.
        */
 
+      cpu = this_cpu();
       g_running_tasks[cpu] = tcb;
 
       /* Restore the cpu lock */
diff --git a/arch/arm/src/armv8-m/arm_doirq.c b/arch/arm/src/armv8-m/arm_doirq.c
index 3e2fe2e961ff0..e35cbb0eef8cc 100644
--- a/arch/arm/src/armv8-m/arm_doirq.c
+++ b/arch/arm/src/armv8-m/arm_doirq.c
@@ -124,11 +124,6 @@ uint32_t *arm_doirq(int irq, uint32_t *regs)
 
       if (regs != tcb->xcp.regs)
         {
-          /* Update scheduler parameters */
-
-          nxsched_suspend_scheduler(g_running_tasks[this_cpu()]);
-          nxsched_resume_scheduler(tcb);
-
           /* Record the new "running" task when context switch occurred.
            * g_running_tasks[] is only used by assertion logic for reporting
            * crashes.
diff --git a/arch/arm/src/armv8-r/arm_doirq.c b/arch/arm/src/armv8-r/arm_doirq.c
index 98c5dc4bc22d0..2863292052b90 100644
--- a/arch/arm/src/armv8-r/arm_doirq.c
+++ b/arch/arm/src/armv8-r/arm_doirq.c
@@ -72,16 +72,10 @@ uint32_t *arm_doirq(int irq, uint32_t *regs)
   /* Deliver the IRQ */
 
   irq_dispatch(irq, regs);
+  tcb = this_task();
 
   if (regs != tcb->xcp.regs)
     {
-      tcb = this_task();
-
-      /* Update scheduler parameters */
-
-      nxsched_suspend_scheduler(g_running_tasks[this_cpu()]);
-      nxsched_resume_scheduler(tcb);
-
       /* Record the new "running" task when context switch occurred.
        * g_running_tasks[] is only used by assertion logic for reporting
        * crashes.
diff --git a/arch/arm/src/armv8-r/arm_syscall.c b/arch/arm/src/armv8-r/arm_syscall.c
index 285613ed4b057..1f82dc20e7b02 100644
--- a/arch/arm/src/armv8-r/arm_syscall.c
+++ b/arch/arm/src/armv8-r/arm_syscall.c
@@ -565,17 +565,11 @@ uint32_t *arm_syscall(uint32_t *regs)
 
   if (regs != tcb->xcp.regs)
     {
-      cpu = this_cpu();
-
-      /* Update scheduler parameters */
-
-      nxsched_suspend_scheduler(g_running_tasks[cpu]);
-      nxsched_resume_scheduler(tcb);
-
       /* Record the new "running" task.  g_running_tasks[] is only used by
        * assertion logic for reporting crashes.
        */
 
+      cpu = this_cpu();
       g_running_tasks[cpu] = tcb;
 
       /* Restore the cpu lock */
diff --git a/arch/arm/src/common/arm_switchcontext.c b/arch/arm/src/common/arm_switchcontext.c
index 946e6441c81b2..ab266f29fb8f0 100644
--- a/arch/arm/src/common/arm_switchcontext.c
+++ b/arch/arm/src/common/arm_switchcontext.c
@@ -55,10 +55,27 @@
 
 void up_switch_context(struct tcb_s *tcb, struct tcb_s *rtcb)
 {
+  /* Update scheduler parameters */
+
+  nxsched_suspend_scheduler(rtcb);
+
   /* Are we in an interrupt handler? */
 
-  if (!up_interrupt_context())
+  if (up_interrupt_context())
     {
+      /* Update scheduler parameters */
+
+      nxsched_resume_scheduler(tcb);
+    }
+
+  /* No, then we will need to perform the user context switch */
+
+  else
+    {
+      /* Update scheduler parameters */
+
+      nxsched_resume_scheduler(tcb);
+
       /* Switch context to the context of the task at the head of the
        * ready to run list.
        */
diff --git a/arch/arm64/src/common/arm64_doirq.c b/arch/arm64/src/common/arm64_doirq.c
index 9806c2c41c043..af0a5abe444c2 100644
--- a/arch/arm64/src/common/arm64_doirq.c
+++ b/arch/arm64/src/common/arm64_doirq.c
@@ -96,11 +96,6 @@ uint64_t *arm64_doirq(int irq, uint64_t * regs)
       addrenv_switch(NULL);
 #endif
 
-      /* Update scheduler parameters */
-
-      nxsched_suspend_scheduler(g_running_tasks[this_cpu()]);
-      nxsched_resume_scheduler(tcb);
-
       /* Record the new "running" task when context switch occurred.
        * g_running_tasks[] is only used by assertion logic for reporting
        * crashes.
diff --git a/arch/arm64/src/common/arm64_switchcontext.c b/arch/arm64/src/common/arm64_switchcontext.c
index 51210b228cc64..b5ab2234d19c3 100644
--- a/arch/arm64/src/common/arm64_switchcontext.c
+++ b/arch/arm64/src/common/arm64_switchcontext.c
@@ -55,10 +55,27 @@
 
 void up_switch_context(struct tcb_s *tcb, struct tcb_s *rtcb)
 {
+  /* Update scheduler parameters */
+
+  nxsched_suspend_scheduler(rtcb);
+
   /* Are we in an interrupt handler? */
 
-  if (!up_interrupt_context())
+  if (up_interrupt_context())
     {
+      /* Update scheduler parameters */
+
+      nxsched_resume_scheduler(tcb);
+    }
+
+  /* No, then we will need to perform the user context switch */
+
+  else
+    {
+      /* Update scheduler parameters */
+
+      nxsched_resume_scheduler(tcb);
+
       /* Switch context to the context of the task at the head of the
        * ready to run list.
        */
diff --git a/arch/arm64/src/common/arm64_syscall.c b/arch/arm64/src/common/arm64_syscall.c
index 5a6c91b0c4c5f..318e7e0cf60f3 100644
--- a/arch/arm64/src/common/arm64_syscall.c
+++ b/arch/arm64/src/common/arm64_syscall.c
@@ -236,9 +236,6 @@ uint64_t *arm64_syscall_switch(uint64_t * regs)
 
   if ((uint64_t *)f_regs != ret_regs)
     {
-      cpu = this_cpu();
-      tcb = current_task(cpu);
-
 #ifdef CONFIG_ARCH_ADDRENV
       /* Make sure that the address environment for the previously
        * running task is closed down gracefully (data caches dump,
@@ -249,15 +246,12 @@ uint64_t *arm64_syscall_switch(uint64_t * regs)
       addrenv_switch(NULL);
 #endif
 
-      /* Update scheduler parameters */
-
-      nxsched_suspend_scheduler(g_running_tasks[cpu]);
-      nxsched_resume_scheduler(tcb);
-
       /* Record the new "running" task.  g_running_tasks[] is only used by
        * assertion logic for reporting crashes.
        */
 
+      cpu = this_cpu();
+      tcb = current_task(cpu);
       g_running_tasks[cpu] = tcb;
 
       /* Restore the cpu lock */
diff --git a/arch/ceva/src/common/ceva_doirq.c b/arch/ceva/src/common/ceva_doirq.c
index c977dc138e8d5..acd5ca82b670c 100644
--- a/arch/ceva/src/common/ceva_doirq.c
+++ b/arch/ceva/src/common/ceva_doirq.c
@@ -78,11 +78,6 @@ uint32_t *ceva_doirq(int irq, uint32_t *regs)
 
       if (regs != up_current_regs())
         {
-          /* Update scheduler parameters */
-
-          nxsched_suspend_scheduler(g_running_tasks[this_cpu()]);
-          nxsched_resume_scheduler(this_task());
-
           /* Record the new "running" task when context switch occurred.
            * g_running_tasks[] is only used by assertion logic for reporting
            * crashes.
diff --git a/arch/ceva/src/common/ceva_switchcontext.c b/arch/ceva/src/common/ceva_switchcontext.c
index 3f5311064f770..4b55564427886 100644
--- a/arch/ceva/src/common/ceva_switchcontext.c
+++ b/arch/ceva/src/common/ceva_switchcontext.c
@@ -69,6 +69,10 @@ void ceva_switchcontext(uint32_t **saveregs, uint32_t *restoreregs)
 
 void up_switch_context(struct tcb_s *tcb, struct tcb_s *rtcb)
 {
+  /* Update scheduler parameters */
+
+  sched_suspend_scheduler(rtcb);
+
   /* Are we in an interrupt handler? */
 
   if (up_current_regs())
@@ -79,6 +83,10 @@ void up_switch_context(struct tcb_s *tcb, struct tcb_s *rtcb)
 
       rtcb->xcp.regs = up_current_regs();
 
+      /* Update scheduler parameters */
+
+      sched_resume_scheduler(tcb);
+
       /* Then switch contexts */
 
       up_set_current_regs(tcb->xcp.regs);
@@ -88,6 +96,10 @@ void up_switch_context(struct tcb_s *tcb, struct tcb_s *rtcb)
 
   else
     {
+      /* Update scheduler parameters */
+
+      sched_resume_scheduler(tcb);
+
       /* Switch context to the context of the task at the head of the
        * ready to run list.
        */
diff --git a/arch/risc-v/src/common/riscv_doirq.c b/arch/risc-v/src/common/riscv_doirq.c
index 23fe5d2bfb30d..895bd910ded1f 100644
--- a/arch/risc-v/src/common/riscv_doirq.c
+++ b/arch/risc-v/src/common/riscv_doirq.c
@@ -109,11 +109,6 @@ uintreg_t *riscv_doirq(int irq, uintreg_t *regs)
       addrenv_switch(NULL);
 #endif
 
-      /* Update scheduler parameters */
-
-      nxsched_suspend_scheduler(g_running_tasks[this_cpu()]);
-      nxsched_resume_scheduler(tcb);
-
       /* Record the new "running" task when context switch occurred.
        * g_running_tasks[] is only used by assertion logic for reporting
        * crashes.
diff --git a/arch/risc-v/src/common/riscv_switchcontext.c b/arch/risc-v/src/common/riscv_switchcontext.c
index 16252b8a2ad89..d7df00ef86bea 100644
--- a/arch/risc-v/src/common/riscv_switchcontext.c
+++ b/arch/risc-v/src/common/riscv_switchcontext.c
@@ -57,6 +57,10 @@
 
 void up_switch_context(struct tcb_s *tcb, struct tcb_s *rtcb)
 {
+  /* Update scheduler parameters */
+
+  nxsched_suspend_scheduler(rtcb);
+
   /* Are we in an interrupt handler? */
 
   if (up_interrupt_context())
@@ -67,6 +71,10 @@ void up_switch_context(struct tcb_s *tcb, struct tcb_s *rtcb)
 
       riscv_savecontext(rtcb);
 
+      /* Update scheduler parameters */
+
+      nxsched_resume_scheduler(tcb);
+
       /* Then switch contexts.  Any necessary address environment
        * changes will be made when the interrupt returns.
        */
@@ -78,6 +86,10 @@ void up_switch_context(struct tcb_s *tcb, struct tcb_s *rtcb)
 
   else
     {
+      /* Update scheduler parameters */
+
+      nxsched_resume_scheduler(tcb);
+
       /* Then switch contexts */
 
       riscv_switchcontext(rtcb, tcb);
diff --git a/arch/x86/src/qemu/qemu_handlers.c b/arch/x86/src/qemu/qemu_handlers.c
index 091d75ff74b11..3e9175ea0e379 100644
--- a/arch/x86/src/qemu/qemu_handlers.c
+++ b/arch/x86/src/qemu/qemu_handlers.c
@@ -116,11 +116,6 @@ static uint32_t *common_handler(int irq, uint32_t *regs)
       addrenv_switch(NULL);
 #endif
 
-      /* Update scheduler parameters */
-
-      nxsched_suspend_scheduler(g_running_tasks[this_cpu()]);
-      nxsched_resume_scheduler(this_task());
-
       /* Record the new "running" task when context switch occurred.
        * g_running_tasks[] is only used by assertion logic for reporting
        * crashes.
diff --git a/arch/x86_64/src/common/x86_64_switchcontext.c b/arch/x86_64/src/common/x86_64_switchcontext.c
index 6a31ca1287031..d876f20a30e5b 100644
--- a/arch/x86_64/src/common/x86_64_switchcontext.c
+++ b/arch/x86_64/src/common/x86_64_switchcontext.c
@@ -59,6 +59,10 @@ void up_switch_context(struct tcb_s *tcb, struct tcb_s *rtcb)
 {
   int cpu;
 
+  /* Update scheduler parameters */
+
+  nxsched_suspend_scheduler(rtcb);
+
   /* Are we in an interrupt handler? */
 
   if (up_interrupt_context())
@@ -71,6 +75,10 @@ void up_switch_context(struct tcb_s *tcb, struct tcb_s *rtcb)
 
       x86_64_restore_auxstate(tcb);
 
+      /* Update scheduler parameters */
+
+      nxsched_resume_scheduler(tcb);
+
       /* Then switch contexts.  Any necessary address environment
        * changes will be made when the interrupt returns.
        */
@@ -86,8 +94,6 @@ void up_switch_context(struct tcb_s *tcb, struct tcb_s *rtcb)
 
   else if (!up_saveusercontext(rtcb->xcp.regs))
     {
-      cpu = this_cpu();
-
       x86_64_restore_auxstate(tcb);
 
 #ifdef CONFIG_ARCH_ADDRENV
@@ -99,20 +105,19 @@ void up_switch_context(struct tcb_s *tcb, struct tcb_s *rtcb)
 
       addrenv_switch(tcb);
 #endif
+      /* Update scheduler parameters */
 
-      /* Restore the cpu lock */
-
-      restore_critical_section(tcb, cpu);
+      nxsched_resume_scheduler(tcb);
 
-      /* Update scheduler parameters */
+      /* Restore the cpu lock */
 
-      nxsched_suspend_scheduler(g_running_tasks[cpu]);
-      nxsched_resume_scheduler(current_task(cpu));
+      restore_critical_section(tcb, this_cpu());
 
       /* Record the new "running" task.  g_running_tasks[] is only used by
        * assertion logic for reporting crashes.
        */
 
+      cpu = this_cpu();
       g_running_tasks[cpu] = current_task(cpu);
 
       /* Then switch contexts */
diff --git a/arch/x86_64/src/intel64/intel64_handlers.c b/arch/x86_64/src/intel64/intel64_handlers.c
index 4101c0f8a433b..28a77e1c73e3d 100644
--- a/arch/x86_64/src/intel64/intel64_handlers.c
+++ b/arch/x86_64/src/intel64/intel64_handlers.c
@@ -97,11 +97,6 @@ static uint64_t *common_handler(int irq, uint64_t *regs)
       addrenv_switch(NULL);
 #endif
 
-      /* Update scheduler parameters */
-
-      nxsched_suspend_scheduler(g_running_tasks[cpu]);
-      nxsched_resume_scheduler(this_task());
-
       /* Record the new "running" task when context switch occurred.
        * g_running_tasks[] is only used by assertion logic for reporting
        * crashes.
diff --git a/arch/xtensa/src/common/xtensa_irqdispatch.c b/arch/xtensa/src/common/xtensa_irqdispatch.c
index daca91ba3eac8..99856c1ed8bd4 100644
--- a/arch/xtensa/src/common/xtensa_irqdispatch.c
+++ b/arch/xtensa/src/common/xtensa_irqdispatch.c
@@ -82,11 +82,6 @@ uint32_t *xtensa_irq_dispatch(int irq, uint32_t *regs)
       addrenv_switch(NULL);
 #endif
 
-      /* Update scheduler parameters */
-
-      nxsched_suspend_scheduler(g_running_tasks[this_cpu()]);
-      nxsched_resume_scheduler(this_task());
-
       /* Record the new "running" task when context switch occurred.
        * g_running_tasks[] is only used by assertion logic for reporting
        * crashes.
diff --git a/arch/xtensa/src/common/xtensa_switchcontext.c b/arch/xtensa/src/common/xtensa_switchcontext.c
index a98e3e1069c37..0f5c4ab865e84 100644
--- a/arch/xtensa/src/common/xtensa_switchcontext.c
+++ b/arch/xtensa/src/common/xtensa_switchcontext.c
@@ -57,10 +57,39 @@
 
 void up_switch_context(struct tcb_s *tcb, struct tcb_s *rtcb)
 {
+  /* Update scheduler parameters */
+
+  nxsched_suspend_scheduler(rtcb);
+
   /* Are we in an interrupt handler? */
 
-  if (!up_current_regs())
+  if (up_current_regs())
     {
+      /* Yes, then we have to do things differently.
+       * Just copy the current_regs into the OLD rtcb.
+       */
+
+      xtensa_savestate(rtcb->xcp.regs);
+
+      /* Update scheduler parameters */
+
+      nxsched_resume_scheduler(tcb);
+
+      /* Then switch contexts.  Any necessary address environment
+       * changes will be made when the interrupt returns.
+       */
+
+      xtensa_restorestate(tcb->xcp.regs);
+    }
+
+  /* No, then we will need to perform the user context switch */
+
+  else
+    {
+      /* Reset scheduler parameters */
+
+      nxsched_resume_scheduler(tcb);
+
       /* Switch context to the context of the task at the head of the
        * ready to run list.
        */