sched/signal: Optimize code logic

Adjust the up_schedule_sigaction function to facilitate subsequent spinlock optimization work.

Signed-off-by: wangzhi16 <wangzhi16@xiaomi.com>

arch/arm/src/arm/arm_schedulesigaction.c

@@ -82,26 +82,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
   sinfo("tcb=%p, rtcb=%p current_regs=%p\n", tcb, this_task(),
         this_task()->xcp.regs);
 
-  /* First, handle some special cases when the signal is
-   * being delivered to the currently executing task.
-   */
-
-  if (tcb == this_task() && !up_interrupt_context())
-    {
-      /* In this case just deliver the signal now. */
-
-      (tcb->sigdeliver)(tcb);
-      tcb->sigdeliver = NULL;
-    }
-
-  /* Otherwise, we are (1) signaling a task is not running
-   * from an interrupt handler or (2) we are not in an
-   * interrupt handler and the running task is signalling
-   * some non-running task.
-   */
-
-  else
-    {
   /* Save the return lr and cpsr and one scratch register
    * These will be restored by the signal trampoline after
    * the signals have been delivered.
@@ -133,5 +113,4 @@ void up_schedule_sigaction(struct tcb_s *tcb)
 #ifdef CONFIG_ARM_THUMB
   tcb->xcp.regs[REG_CPSR] |= PSR_T_BIT;
 #endif
-    }
 }

arch/arm/src/armv6-m/arm_schedulesigaction.c

@@ -90,16 +90,7 @@ void up_schedule_sigaction(struct tcb_s *tcb)
    * being delivered to the currently executing task.
    */
 
-  if (tcb == rtcb && ipsr == 0)
+  if (tcb == rtcb && ipsr != NVIC_IRQ_PENDSV)
-    {
-      /* In this case just deliver the signal now.
-       * REVISIT:  Signal handle will run in a critical section!
-       */
-
-      (tcb->sigdeliver)(tcb);
-      tcb->sigdeliver = NULL;
-    }
-  else if (tcb == rtcb && ipsr != NVIC_IRQ_PENDSV)
     {
       /* Context switch should be done in pendsv, for exception directly
        * last regs is not saved tcb->xcp.regs.

arch/arm/src/armv7-a/arm_schedulesigaction.c

@@ -84,21 +84,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
   sinfo("tcb=%p, rtcb=%p current_regs=%p\n", tcb, this_task(),
         this_task()->xcp.regs);
 
-  /* First, handle some special cases when the signal is
-   * being delivered to the currently executing task.
-   */
-
-  if (tcb == this_task() && !up_interrupt_context())
-    {
-      /* In this case just deliver the signal now.
-       * REVISIT:  Signal handler will run in a critical section!
-       */
-
-      (tcb->sigdeliver)(tcb);
-      tcb->sigdeliver = NULL;
-    }
-  else
-    {
   /* Save the return lr and cpsr and one scratch register.  These
    * will be restored by the signal trampoline after the signals
    * have been delivered.
@@ -130,5 +115,4 @@ void up_schedule_sigaction(struct tcb_s *tcb)
 #ifdef CONFIG_ARM_THUMB
   tcb->xcp.regs[REG_CPSR] |= PSR_T_BIT;
 #endif
-    }
 }

arch/arm/src/armv7-m/arm_schedulesigaction.c

@@ -91,16 +91,7 @@ void up_schedule_sigaction(struct tcb_s *tcb)
    * being delivered to the currently executing task.
    */
 
-  if (tcb == rtcb && ipsr == 0)
+  if (tcb == rtcb && ipsr != NVIC_IRQ_PENDSV)
-    {
-      /* In this case just deliver the signal now.
-       * REVISIT:  Signal handle will run in a critical section!
-       */
-
-      (tcb->sigdeliver)(tcb);
-      tcb->sigdeliver = NULL;
-    }
-  else if (tcb == rtcb && ipsr != NVIC_IRQ_PENDSV)
     {
       /* Context switch should be done in pendsv, for exception directly
        * last regs is not saved tcb->xcp.regs.

arch/arm/src/armv7-r/arm_schedulesigaction.c

@@ -82,21 +82,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
   sinfo("tcb=%p, rtcb=%p current_regs=%p\n", tcb, this_task(),
         this_task()->xcp.regs);
 
-  /* First, handle some special cases when the signal is
-   * being delivered to the currently executing task.
-   */
-
-  if (tcb == this_task() && !up_interrupt_context())
-    {
-      /* In this case just deliver the signal now.
-       * REVISIT:  Signal handler will run in a critical section!
-       */
-
-      (tcb->sigdeliver)(tcb);
-      tcb->sigdeliver = NULL;
-    }
-  else
-    {
   /* Save the return lr and cpsr and one scratch register.  These
    * will be restored by the signal trampoline after the signals
    * have been delivered.
@@ -128,5 +113,4 @@ void up_schedule_sigaction(struct tcb_s *tcb)
 #ifdef CONFIG_ARM_THUMB
   tcb->xcp.regs[REG_CPSR] |= PSR_T_BIT;
 #endif
-    }
 }

arch/arm/src/armv8-m/arm_schedulesigaction.c

@@ -91,16 +91,7 @@ void up_schedule_sigaction(struct tcb_s *tcb)
    * being delivered to the currently executing task.
    */
 
-  if (tcb == rtcb && ipsr == 0)
+  if (tcb == rtcb && ipsr != NVIC_IRQ_PENDSV)
-    {
-      /* In this case just deliver the signal now.
-       * REVISIT:  Signal handle will run in a critical section!
-       */
-
-      (tcb->sigdeliver)(tcb);
-      tcb->sigdeliver = NULL;
-    }
-  else if (tcb == rtcb && ipsr != NVIC_IRQ_PENDSV)
     {
       /* Context switch should be done in pendsv, for exception directly
        * last regs is not saved tcb->xcp.regs.

arch/arm/src/armv8-r/arm_schedulesigaction.c

@@ -82,21 +82,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
   sinfo("tcb=%p, rtcb=%p current_regs=%p\n", tcb, this_task(),
         this_task()->xcp.regs);
 
-  /* First, handle some special cases when the signal is
-   * being delivered to the currently executing task.
-   */
-
-  if (tcb == this_task() && !up_interrupt_context())
-    {
-      /* In this case just deliver the signal now.
-       * REVISIT:  Signal handler will run in a critical section!
-       */
-
-      (tcb->sigdeliver)(tcb);
-      tcb->sigdeliver = NULL;
-    }
-  else
-    {
   /* Save the return lr and cpsr and one scratch register.  These
    * will be restored by the signal trampoline after the signals
    * have been delivered.
@@ -128,5 +113,4 @@ void up_schedule_sigaction(struct tcb_s *tcb)
 #ifdef CONFIG_ARM_THUMB
   tcb->xcp.regs[REG_CPSR] |= PSR_T_BIT;
 #endif
-    }
 }

arch/arm/src/tlsr82/tc32/tc32_schedulesigaction.c

@@ -82,26 +82,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
   sinfo("tcb=%p, rtcb=%p current_regs=%p\n", tcb, this_task(),
         this_task()->xcp.regs);
 
-  /* First, handle some special cases when the signal is
-   * being delivered to the currently executing task.
-   */
-
-  if (tcb == this_task() && !up_interrupt_context())
-    {
-      /* In this case just deliver the signal now. */
-
-      (tcb->sigdeliver)(tcb);
-      tcb->sigdeliver = NULL;
-    }
-
-  /* Otherwise, we are (1) signaling a task is not running
-   * from an interrupt handler or (2) we are not in an
-   * interrupt handler and the running task is signalling
-   * some non-running task.
-   */
-
-  else
-    {
   /* Save the return lr and cpsr and one scratch register
    * These will be restored by the signal trampoline after
    * the signals have been delivered.
@@ -130,5 +110,4 @@ void up_schedule_sigaction(struct tcb_s *tcb)
   tcb->xcp.regs[REG_LR]     = (uint32_t)arm_sigdeliver;
   tcb->xcp.regs[REG_CPSR]   = PSR_MODE_SVC | PSR_I_BIT;
   tcb->xcp.regs[REG_IRQ_EN] = 0;
-    }
 }

arch/arm64/src/common/arm64_schedulesigaction.c

@@ -126,21 +126,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
   sinfo("tcb=%p, rtcb=%p current_regs=%p\n", tcb, this_task(),
         this_task()->xcp.regs);
 
-  /* First, handle some special cases when the signal is
-   * being delivered to the currently executing task.
-   */
-
-  if (tcb == this_task() && !up_interrupt_context())
-    {
-      /* In this case just deliver the signal now.
-       * REVISIT:  Signal handler will run in a critical section!
-       */
-
-      (tcb->sigdeliver)(tcb);
-      tcb->sigdeliver = NULL;
-    }
-  else
-    {
   /* Save the return lr and cpsr and one scratch register.  These
    * will be restored by the signal trampoline after the signals
    * have been delivered.
@@ -151,5 +136,4 @@ void up_schedule_sigaction(struct tcb_s *tcb)
   /* create signal process context */
 
   arm64_init_signal_process(tcb, NULL);
-    }
 }

arch/avr/src/avr/avr_schedulesigaction.c

@@ -89,32 +89,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
    */
 
   if (tcb == this_task())
-    {
-      /* CASE 1:  We are not in an interrupt handler and
-       * a task is signalling itself for some reason.
-       */
-
-      if (!up_current_regs())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  We are in an interrupt handler AND the
-       * interrupted task is the same as the one that
-       * must receive the signal, then we will have to modify
-       * the return state as well as the state in the TCB.
-       *
-       * Hmmm... there looks like a latent bug here: The following
-       * logic would fail in the strange case where we are in an
-       * interrupt handler, the thread is signalling itself, but
-       * a context switch to another task has occurred so that
-       * g_current_regs does not refer to the thread of this_task()!
-       */
-
-      else
     {
       /* Save registers that must be protected while the signal
        * handler runs. These will be restored by the signal
@@ -151,7 +125,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
 
       avr_savestate(tcb->xcp.regs);
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running
    * from an interrupt handler or (2) we are not in an

arch/avr/src/avr32/avr_schedulesigaction.c

@@ -87,32 +87,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
    */
 
   if (tcb == this_task())
-    {
-      /* CASE 1:  We are not in an interrupt handler and
-       * a task is signalling itself for some reason.
-       */
-
-      if (!up_current_regs())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  We are in an interrupt handler AND the
-       * interrupted task is the same as the one that
-       * must receive the signal, then we will have to modify
-       * the return state as well as the state in the TCB.
-       *
-       * Hmmm... there looks like a latent bug here: The following
-       * logic would fail in the strange case where we are in an
-       * interrupt handler, the thread is signalling itself, but
-       * a context switch to another task has occurred so that
-       * g_current_regs does not refer to the thread of this_task()!
-       */
-
-      else
     {
       /* Save registers that must be protected while the signal
        * handler runs. These will be restored by the signal
@@ -135,7 +109,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
 
       avr_savestate(tcb->xcp.regs);
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running
    * from an interrupt handler or (2) we are not in an

arch/ceva/src/common/ceva_schedulesigaction.c

@@ -84,35 +84,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
    */
 
   if (tcb->task_state == TSTATE_TASK_RUNNING)
-    {
-      uint8_t me  = this_cpu();
-#ifdef CONFIG_SMP
-      uint8_t cpu = tcb->cpu;
-#else
-      uint8_t cpu = 0;
-#endif
-
-      /* CASE 1:  We are not in an interrupt handler and a task is
-       * signaling itself for some reason.
-       */
-
-      if (cpu == me && !up_current_regs())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  The task that needs to receive the signal is running.
-       * This could happen if the task is running on another CPU OR if
-       * we are in an interrupt handler and the task is running on this
-       * CPU.  In the former case, we will have to PAUSE the other CPU
-       * first.  But in either case, we will have to modify the return
-       * state as well as the state in the TCB.
-       */
-
-      else
     {
       /* Save the current register context location */
 
@@ -140,7 +111,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
       up_current_regs()[REG_OM] |=  REG_OM_KERNEL;
 #endif
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running from an
    * interrupt handler or (2) we are not in an interrupt handler and the

arch/mips/src/mips32/mips_schedulesigaction.c

@@ -90,32 +90,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
    */
 
   if (tcb == this_task())
-    {
-      /* CASE 1:  We are not in an interrupt handler and
-       * a task is signalling itself for some reason.
-       */
-
-      if (!up_current_regs())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  We are in an interrupt handler AND the
-       * interrupted task is the same as the one that
-       * must receive the signal, then we will have to modify
-       * the return state as well as the state in the TCB.
-       *
-       * Hmmm... there looks like a latent bug here: The following
-       * logic would fail in the strange case where we are in an
-       * interrupt handler, the thread is signalling itself, but
-       * a context switch to another task has occurred so that
-       * g_current_regs does not refer to the thread of this_task()!
-       */
-
-      else
     {
       /* Save the return EPC and STATUS registers.  These will be
        * restored by the signal trampoline after the signals have
@@ -147,7 +121,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
             up_current_regs()[REG_EPC],
             up_current_regs()[REG_STATUS]);
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running
    * from an interrupt handler or (2) we are not in an

arch/misoc/src/lm32/lm32_schedulesigaction.c

@@ -87,32 +87,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
    */
 
   if (tcb == this_task())
-    {
-      /* CASE 1:  We are not in an interrupt handler and
-       * a task is signalling itself for some reason.
-       */
-
-      if (!up_current_regs())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  We are in an interrupt handler AND the
-       * interrupted task is the same as the one that
-       * must receive the signal, then we will have to modify
-       * the return state as well as the state in the TCB.
-       *
-       * Hmmm... there looks like a latent bug here: The following
-       * logic would fail in the strange case where we are in an
-       * interrupt handler, the thread is signalling itself, but
-       * a context switch to another task has occurred so that
-       * g_current_regs does not refer to the thread of this_task()!
-       */
-
-      else
     {
       /* Save the return EPC and STATUS registers.  These will be
        * restored by the signal trampoline after the signals have
@@ -139,7 +113,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
             up_current_regs()[REG_EPC],
             up_current_regs()[REG_STATUS]);
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running
    * from an interrupt handler or (2) we are not in an

arch/misoc/src/minerva/minerva_schedulesigaction.c

@@ -88,32 +88,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
    */
 
   if (tcb == this_task())
-    {
-      /* CASE 1: We are not in an interrupt handler and a task is
-       * signalling itself for some reason.
-       */
-
-      if (!up_current_regs())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2: We are in an interrupt handler AND the interrupted task
-       * is the same as the one that must receive the signal, then we
-       * will have to modify the return state as well as the state in
-       * the TCB.
-       *
-       * Hmmm... there looks like a latent bug here: The following logic
-       * would fail in the strange case where we are in an interrupt
-       * handler, the thread is signalling itself, but a context switch
-       * to another task has occurred so that g_current_regs does not
-       * refer to the thread of this_task()!
-       */
-
-      else
     {
       /* Save the return EPC and STATUS registers.  These will be
        * restored by the signal trampoline after the signals have
@@ -141,7 +115,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
             up_current_regs()[REG_CSR_MEPC],
             up_current_regs()[REG_CSR_MSTATUS]);
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running from an
    * interrupt handler or (2) we are not in an interrupt handler and the

arch/or1k/src/common/or1k_schedulesigaction.c

@@ -86,32 +86,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
    */
 
   if (tcb == this_task())
-    {
-      /* CASE 1:  We are not in an interrupt handler and
-       * a task is signalling itself for some reason.
-       */
-
-      if (!up_current_regs())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  We are in an interrupt handler AND the
-       * interrupted task is the same as the one that
-       * must receive the signal, then we will have to modify
-       * the return state as well as the state in the TCB.
-       *
-       * Hmmm... there looks like a latent bug here: The following
-       * logic would fail in the strange case where we are in an
-       * interrupt handler, the thread is signalling itself, but
-       * a context switch to another task has occurred so that
-       * current_regs does not refer to the thread of this_task()!
-       */
-
-      else
     {
       /* Save the return lr and cpsr and one scratch register
        * These will be restored by the signal trampoline after
@@ -137,7 +111,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
 
       or1k_savestate(tcb->xcp.regs);
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running
    * from an interrupt handler or (2) we are not in an

arch/renesas/src/m16c/m16c_schedulesigaction.c

@@ -86,26 +86,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
    */
 
   if (tcb == this_task())
-    {
-      /* CASE 1:  We are not in an interrupt handler and
-       * a task is signalling itself for some reason.
-       */
-
-      if (!up_current_regs())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  We are in an interrupt handler AND the
-       * interrupted task is the same as the one that
-       * must receive the signal, then we will have to modify
-       * the return state as well as the state in the TCB.
-       */
-
-      else
     {
       /* Save the return PC and SR and one scratch register
        * These will be restored by the signal trampoline after
@@ -130,7 +110,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
 
       renesas_copystate(tcb->xcp.regs, up_current_regs());
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running
    * from an interrupt handler or (2) we are not in an

arch/renesas/src/rx65n/rx65n_schedulesigaction.c

@@ -86,26 +86,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
    */
 
   if (tcb == this_task())
-    {
-      /* CASE 1:  We are not in an interrupt handler and
-       * a task is signalling itself for some reason.
-       */
-
-      if (!up_current_regs())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  We are in an interrupt handler AND the
-       * interrupted task is the same as the one that
-       * must receive the signal, then we will have to modify
-       * the return state as well as the state in the TCB.
-       */
-
-      else
     {
       /* Save the return PC and SR and one scratch register
        * These will be restored by the signal trampoline after
@@ -128,7 +108,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
 
       renesas_copystate(tcb->xcp.regs, up_current_regs());
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running
    * from an interrupt handler or (2) we are not in an

arch/renesas/src/sh1/sh1_schedulesigaction.c

@@ -86,26 +86,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
    */
 
   if (tcb == this_task())
-    {
-      /* CASE 1:  We are not in an interrupt handler and
-       * a task is signalling itself for some reason.
-       */
-
-      if (!up_current_regs())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  We are in an interrupt handler AND the
-       * interrupted task is the same as the one that
-       * must receive the signal, then we will have to modify
-       * the return state as well as the state in the TCB.
-       */
-
-      else
     {
       /* Save the return PC and SR and one scratch register
        * These will be restored by the signal trampoline after
@@ -128,7 +108,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
 
       renesas_copystate(tcb->xcp.regs, up_current_regs());
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running
    * from an interrupt handler or (2) we are not in an

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

@@ -85,21 +85,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
   sinfo("tcb=%p, rtcb=%p current_regs=%p\n", tcb, this_task(),
         this_task()->xcp.regs);
 
-  /* First, handle some special cases when the signal is being delivered
-   * to task that is currently executing on any CPU.
-   */
-
-  if (tcb == this_task() && !up_interrupt_context())
-    {
-      /* In this case just deliver the signal now.
-       * REVISIT:  Signal handler will run in a critical section!
-       */
-
-      (tcb->sigdeliver)(tcb);
-      tcb->sigdeliver = NULL;
-    }
-  else
-    {
   /* Save the return EPC and STATUS registers.  These will be
    * by the signal trampoline after the signal has been delivered.
    */
@@ -136,5 +121,4 @@ void up_schedule_sigaction(struct tcb_s *tcb)
 #endif
 
   tcb->xcp.regs[REG_INT_CTX] = int_ctx;
-    }
 }

arch/sparc/src/sparc_v8/sparc_v8_schedulesigaction.c

@@ -84,32 +84,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
    */
 
   if (tcb == this_task())
-    {
-      /* CASE 1:  We are not in an interrupt handler and
-       * a task is signalling itself for some reason.
-       */
-
-      if (!up_current_regs())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  We are in an interrupt handler AND the
-       * interrupted task is the same as the one that
-       * must receive the signal, then we will have to modify
-       * the return state as well as the state in the TCB.
-       *
-       * Hmmm... there looks like a latent bug here: The following
-       * logic would fail in the strange case where we are in an
-       * interrupt handler, the thread is signalling itself, but
-       * a context switch to another task has occurred so that
-       * current_regs does not refer to the thread of this_task()!
-       */
-
-      else
     {
       /* Save registers that must be protected while the signal
        * handler runs. These will be restored by the signal
@@ -134,7 +108,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
 
       sparc_savestate(tcb->xcp.regs);
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running
    * from an interrupt handler or (2) we are not in an
@@ -167,9 +140,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
 #ifdef CONFIG_SMP
 void up_schedule_sigaction(struct tcb_s *tcb)
 {
-  int cpu;
-  int me;
-
   sinfo("tcb=%p, rtcb=%p current_regs=%p\n", tcb,
         this_task(), up_current_regs());
 
@@ -179,35 +149,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
 
   if (tcb->task_state == TSTATE_TASK_RUNNING)
     {
-      me  = this_cpu();
-      cpu = tcb->cpu;
-
-      /* CASE 1:  We are not in an interrupt handler and a task is
-       * signaling itself for some reason.
-       */
-
-      if (cpu == me && !up_current_regs())
-        {
-          /* In this case just deliver the signal now.
-           * REVISIT:  Signal handler will run in a critical section!
-           */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  The task that needs to receive the signal is running.
-       * This could happen if the task is running on another CPU OR if
-       * we are in an interrupt handler and the task is running on this
-       * CPU.  In the former case, we will have to PAUSE the other CPU
-       * first.  But in either case, we will have to modify the return
-       * state as well as the state in the TCB.
-       */
-
-      else
-        {
-          /* tcb is running on the same CPU */
-
       /* Save registers that must be protected while the signal
        * handler runs. These will be restored by the signal
        * trampoline after the signal(s) have been delivered.
@@ -233,7 +174,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
 
       sparc_savestate(tcb->xcp.regs);
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running from an
    * interrupt handler or (2) we are not in an interrupt handler and the

arch/tricore/src/common/tricore_schedulesigaction.c

@@ -80,38 +80,6 @@
 
 void up_schedule_sigaction(struct tcb_s *tcb)
 {
-  /* First, handle some special cases when the signal is
-   * being delivered to the currently executing task.
-   */
-
-  if (tcb == this_task())
-    {
-      /* CASE 1:  We are not in an interrupt handler and
-       * a task is signalling itself for some reason.
-       */
-
-      if (!up_interrupt_context())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  We are in an interrupt handler AND the
-       * interrupted task is the same as the one that
-       * must receive the signal, then we will have to modify
-       * the return state as well as the state in the TCB.
-       *
-       * Hmmm... there looks like a latent bug here: The following
-       * logic would fail in the strange case where we are in an
-       * interrupt handler, the thread is signalling itself, but
-       * a context switch to another task has occurred so that
-       * g_current_regs does not refer to the thread of this_task()!
-       */
-
-      else
-        {
   /* Save the context registers.  These will be
    * restored by the signal trampoline after the signals have
    * been delivered.
@@ -123,38 +91,8 @@ void up_schedule_sigaction(struct tcb_s *tcb)
    * will borrow the process stack of the current tcb.
    */
 
-          tcb->xcp.regs =
+  tcb->xcp.regs = tricore_alloc_csa((uintptr_t)tricore_sigdeliver,
-            tricore_alloc_csa((uintptr_t)tricore_sigdeliver,
                                     STACKFRAME_ALIGN_DOWN
                                     (up_getusrsp(tcb->xcp.regs)),
                                     PSW_IO_SUPERVISOR | PSW_CDE, true);
-        }
-    }
-
-  /* Otherwise, we are (1) signaling a task is not running
-   * from an interrupt handler or (2) we are not in an
-   * interrupt handler and the running task is signalling
-   * some non-running task.
-   */
-
-  else
-    {
-      /* Save the return EPC and STATUS registers.  These will be
-       * restored by the signal trampoline after the signals have
-       * been delivered.
-       */
-
-      /* Save the current register context location */
-
-      tcb->xcp.saved_regs = tcb->xcp.regs;
-
-      /* Create a new CSA for signal delivery. The new context
-       * will borrow the process stack of the current tcb.
-       */
-
-      tcb->xcp.regs =
-        tricore_alloc_csa((uintptr_t)tricore_sigdeliver,
-                          STACKFRAME_ALIGN_DOWN(up_getusrsp(tcb->xcp.regs)),
-                          PSW_IO_SUPERVISOR | PSW_CDE, true);
-    }
 }

arch/x86/src/i486/i486_schedulesigaction.c

@@ -82,32 +82,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
    */
 
   if (tcb == this_task())
-    {
-      /* CASE 1:  We are not in an interrupt handler and a task is
-       * signalling itself for some reason.
-       */
-
-      if (!up_current_regs())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  We are in an interrupt handler AND the interrupted task
-       * is the same as the one that must receive the signal, then we
-       * will have to modify the return state as well as the state in the
-       * TCB.
-       *
-       * Hmmm... there looks like a latent bug here: The following logic
-       * would fail in the strange case where we are in an interrupt
-       * handler, the thread is signalling itself, but a context switch
-       * to another task has occurred so that g_current_regs does not
-       * refer to the thread of this_task()!
-       */
-
-      else
     {
       /* Save the return lr and cpsr and one scratch register. These
        * will be restored by the signal trampoline after the signals
@@ -130,7 +104,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
 
       x86_savestate(tcb->xcp.regs);
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running
    * from an interrupt handler or (2) we are not in an

arch/x86_64/src/intel64/intel64_schedulesigaction.c

@@ -77,23 +77,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
   sinfo("tcb=%p, rtcb=%p current_regs=%p\n", tcb,
         this_task(), this_task()->xcp.regs);
 
-  /* First, handle some special cases when the signal is being delivered
-   * to task that is currently executing on any CPU.
-   */
-
-  if (tcb == this_task() && !up_interrupt_context())
-    {
-      (tcb->sigdeliver)(tcb);
-      tcb->sigdeliver = NULL;
-    }
-
-  /* Otherwise, we are (1) signaling a task is not running from an
-   * interrupt handler or (2) we are not in an interrupt handler and the
-   * running task is signaling some other non-running task.
-   */
-
-  else
-    {
   /* Save the return lr and cpsr and one scratch register
    * These will be restored by the signal trampoline after
    * the signals have been delivered.
@@ -110,5 +93,4 @@ void up_schedule_sigaction(struct tcb_s *tcb)
   tcb->xcp.regs[REG_RIP]    = (uint64_t)x86_64_sigdeliver;
   tcb->xcp.regs[REG_RSP]    = tcb->xcp.regs[REG_RSP] - 8;
   tcb->xcp.regs[REG_RFLAGS] = 0;
-    }
 }

arch/xtensa/src/common/xtensa_schedsigaction.c

@@ -85,21 +85,6 @@ void up_schedule_sigaction(struct tcb_s *tcb)
   sinfo("tcb=%p, rtcb=%p current_regs=%p\n", tcb, this_task(),
         this_task()->xcp.regs);
 
-  /* First, handle some special cases when the signal is being delivered
-   * to task that is currently executing on any CPU.
-   */
-
-  if (tcb == this_task() && !up_interrupt_context())
-    {
-      /* In this case just deliver the signal now.
-       * REVISIT:  Signal handler will run in a critical section!
-       */
-
-      (tcb->sigdeliver)(tcb);
-      tcb->sigdeliver = NULL;
-    }
-  else
-    {
   /* Save the context registers.  These will be restored by the
    * signal trampoline after the signals have been delivered.
    *
@@ -132,15 +117,12 @@ void up_schedule_sigaction(struct tcb_s *tcb)
 
   tcb->xcp.regs[REG_PC] = (uint32_t)xtensa_sig_deliver;
 #ifdef __XTENSA_CALL0_ABI__
-      tcb->xcp.regs[REG_PS] = (uint32_t)
+  tcb->xcp.regs[REG_PS] = (PS_INTLEVEL(XCHAL_EXCM_LEVEL) | PS_UM);
-          (PS_INTLEVEL(XCHAL_EXCM_LEVEL) | PS_UM);
 #else
-      tcb->xcp.regs[REG_PS] = (uint32_t)
+  tcb->xcp.regs[REG_PS] = (PS_INTLEVEL(XCHAL_EXCM_LEVEL) | PS_UM |
-          (PS_INTLEVEL(XCHAL_EXCM_LEVEL) | PS_UM |
                            PS_WOE | PS_CALLINC(1));
 #endif
 #ifndef CONFIG_BUILD_FLAT
   xtensa_raiseprivilege(tcb->xcp.regs);
 #endif
-    }
 }

arch/z16/src/common/z16_schedulesigaction.c

@@ -86,26 +86,6 @@ void up_schedule_sigaction(FAR struct tcb_s *tcb)
    */
 
   if (tcb == this_task())
-    {
-      /* CASE 1:  We are not in an interrupt handler and
-       * a task is signalling itself for some reason.
-       */
-
-      if (!up_current_regs())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  We are in an interrupt handler AND the interrupted
-       * task is the same as the one that must receive the signal, then
-       * we will have to modify the return state as well as the state
-       * in the TCB.
-       */
-
-      else
     {
       FAR uint32_t *current_pc  =
         (FAR uint32_t *)&up_current_regs()[REG_PC];
@@ -131,7 +111,6 @@ void up_schedule_sigaction(FAR struct tcb_s *tcb)
 
       z16_copystate(tcb->xcp.regs, up_current_regs());
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running from an
    * interrupt handler or (2) we are not in an interrupt handler

arch/z80/src/ez80/ez80_schedulesigaction.c

@@ -110,26 +110,6 @@ void up_schedule_sigaction(FAR struct tcb_s *tcb)
    */
 
   if (tcb == this_task())
-    {
-      /* CASE 1:  We are not in an interrupt handler and a task is
-       * signalling itself for some reason.
-       */
-
-      if (!IN_INTERRUPT())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  We are in an interrupt handler AND the interrupted task
-       * is the same as the one that must receive the signal, then we
-       * will have to modify the return state as well as the state in
-       * the TCB.
-       */
-
-      else
     {
       /* Set up to vector to the trampoline with interrupts
        * disabled.
@@ -143,7 +123,6 @@ void up_schedule_sigaction(FAR struct tcb_s *tcb)
 
       SAVE_IRQCONTEXT(tcb);
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running from an
    * interrupt handler or (2) we are not in an interrupt handler and the

arch/z80/src/z180/z180_schedulesigaction.c

@@ -113,26 +113,6 @@ void up_schedule_sigaction(FAR struct tcb_s *tcb)
    */
 
   if (tcb == this_task())
-    {
-      /* CASE 1:  We are not in an interrupt handler and a task is
-       * signalling itself for some reason.
-       */
-
-      if (!IN_INTERRUPT())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  We are in an interrupt handler AND the interrupted task
-       * is the same as the one that must receive the signal, then we
-       * will have to modify the return state as well as the state in
-       * the TCB.
-       */
-
-      else
     {
       /* Set up to vector to the trampoline with interrupts
        * disabled.
@@ -146,7 +126,6 @@ void up_schedule_sigaction(FAR struct tcb_s *tcb)
 
       SAVE_IRQCONTEXT(tcb);
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running
    * from an interrupt handler or (2) we are not in an

arch/z80/src/z8/z8_schedulesigaction.c

@@ -110,26 +110,6 @@ void up_schedule_sigaction(FAR struct tcb_s *tcb)
    */
 
   if (tcb == this_task())
-    {
-      /* CASE 1:  We are not in an interrupt handler and a task is
-       * signalling itself for some reason.
-       */
-
-      if (!IN_INTERRUPT())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  We are in an interrupt handler AND the interrupted task
-       * is the same as the one that must receive the signal, then we
-       * will have to modify the return state as well as the state in
-       * the TCB.
-       */
-
-      else
     {
       /* Set up to vector to the trampoline with interrupts
        * disabled.
@@ -143,7 +123,6 @@ void up_schedule_sigaction(FAR struct tcb_s *tcb)
 
       SAVE_IRQCONTEXT(tcb);
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running
    * from an interrupt handler or (2) we are not in an

arch/z80/src/z80/z80_schedulesigaction.c

@@ -111,26 +111,6 @@ void up_schedule_sigaction(FAR struct tcb_s *tcb)
    */
 
   if (tcb == this_task())
-    {
-      /* CASE 1:  We are not in an interrupt handler and a task is
-       * signalling itself for some reason.
-       */
-
-      if (!IN_INTERRUPT())
-        {
-          /* In this case just deliver the signal now. */
-
-          (tcb->sigdeliver)(tcb);
-          tcb->sigdeliver = NULL;
-        }
-
-      /* CASE 2:  We are in an interrupt handler AND the interrupted task
-       * is the same as the one that must receive the signal, then we
-       * will have to modify the return state as well as the state in
-       * the TCB.
-       */
-
-      else
     {
       /* Set up to vector to the trampoline with interrupts
        * disabled.
@@ -144,7 +124,6 @@ void up_schedule_sigaction(FAR struct tcb_s *tcb)
 
       SAVE_IRQCONTEXT(tcb);
     }
-    }
 
   /* Otherwise, we are (1) signaling a task is not running
    * from an interrupt handler or (2) we are not in an

sched/signal/sig_dispatch.c

@@ -185,11 +185,21 @@ static int nxsig_queue_action(FAR struct tcb_s *stcb,
 #endif
                 {
                   stcb->sigdeliver = nxsig_deliver;
+                  if (stcb == this_task() && !up_interrupt_context())
+                    {
+                      /* In this case just deliver the signal now. */
+
+                      (stcb->sigdeliver)(stcb);
+                      stcb->sigdeliver = NULL;
+                    }
+                  else
+                    {
                       up_schedule_sigaction(stcb);
                     }
                 }
             }
         }
+    }
 
   return ret;
 }