riscv: remove up_set_current_regs/up_current_regs

reason:
up_set_current_regs initially had two functions:

1: To mark the entry into an interrupt state.
2: To record the context before an interrupt/exception. If we switch to a new task, we need to store the upcoming context regs by calling up_set_current_regs(regs).

Currently, we record the context in other ways, so the second function is obsolete. Therefore, we need to rename up_set_current_regs to better reflect its actual meaning, which is solely to mark an interrupt.

Signed-off-by: hujun5 <hujun5@xiaomi.com>

arch/risc-v/include/irq.h

@@ -673,17 +673,9 @@ extern "C"
 #define EXTERN extern
 #endif
 
-/* g_current_regs[] holds a references to the current interrupt level
- * register storage structure.  If is non-NULL only during interrupt
- * processing.  Access to g_current_regs[] must be through the
- * [get/set]_current_regs for portability.
- */
+/* g_interrupt_context store irq status */
 
-/* For the case of architectures with multiple CPUs, then there must be one
- * such value for each processor that can receive an interrupt.
- */
-
-EXTERN volatile uintreg_t *g_current_regs[CONFIG_SMP_NCPUS];
+EXTERN volatile bool g_interrupt_context[CONFIG_SMP_NCPUS];
 
 /****************************************************************************
  * Public Function Prototypes
@@ -726,24 +718,6 @@ int up_this_cpu(void);
  * Inline Functions
  ****************************************************************************/
 
-static inline_function uintreg_t *up_current_regs(void)
-{
-#ifdef CONFIG_SMP
-  return (uintreg_t *)g_current_regs[up_this_cpu()];
-#else
-  return (uintreg_t *)g_current_regs[0];
-#endif
-}
-
-static inline_function void up_set_current_regs(uintreg_t *regs)
-{
-#ifdef CONFIG_SMP
-  g_current_regs[up_this_cpu()] = regs;
-#else
-  g_current_regs[0] = regs;
-#endif
-}
-
 /****************************************************************************
  * Name: up_irq_save
  *
@@ -792,6 +766,24 @@ noinstrument_function static inline void up_irq_restore(irqstate_t flags)
     );
 }
 
+/****************************************************************************
+ * Name: up_set_interrupt_context
+ *
+ * Description:
+ *   Set the interrupt handler context.
+ *
+ ****************************************************************************/
+
+noinstrument_function
+static inline_function void up_set_interrupt_context(bool flag)
+{
+#ifdef CONFIG_SMP
+  g_interrupt_context[up_this_cpu()] = flag;
+#else
+  g_interrupt_context[0] = flag;
+#endif
+}
+
 /****************************************************************************
  * Name: up_interrupt_context
  *
@@ -805,15 +797,12 @@ noinstrument_function static inline_function bool up_interrupt_context(void)
 {
 #ifdef CONFIG_SMP
   irqstate_t flags = up_irq_save();
-#endif
-
-  bool ret = up_current_regs() != NULL;
-
-#ifdef CONFIG_SMP
+  bool ret = g_interrupt_context[up_this_cpu()];
   up_irq_restore(flags);
-#endif
-
   return ret;
+#else
+  return g_interrupt_context[0];
+#endif
 }
 
 /****************************************************************************
@@ -821,7 +810,7 @@ noinstrument_function static inline_function bool up_interrupt_context(void)
  ****************************************************************************/
 
 #define up_getusrpc(regs) \
-    (((uintptr_t *)((regs) ? (regs) : up_current_regs()))[REG_EPC])
+    (((uintptr_t *)((regs) ? (regs) : running_regs()))[REG_EPC])
 
 #undef EXTERN
 #if defined(__cplusplus)

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

@@ -164,8 +164,8 @@ int up_backtrace(struct tcb_s *tcb, void **buffer, int size, int skip)
             {
               ret += backtrace(rtcb->stack_base_ptr,
                                rtcb->stack_base_ptr + rtcb->adj_stack_size,
-                               (void *)up_current_regs()[REG_FP],
-                               (void *)up_current_regs()[REG_EPC],
+                               running_regs()[REG_FP],
+                               running_regs()[REG_EPC],
                                &buffer[ret], size - ret, &skip);
             }
         }

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

@@ -83,26 +83,20 @@ uintreg_t *riscv_doirq(int irq, uintreg_t *regs)
       (*running_task)->xcp.regs = regs;
     }
 
-  /* Current regs non-zero indicates that we are processing an interrupt;
-   * current_regs is also used to manage interrupt level context switches.
-   *
-   * Nested interrupts are not supported
-   */
+  /* Nested interrupts are not supported */
 
-  DEBUGASSERT(up_current_regs() == NULL);
-  up_set_current_regs(regs);
+  DEBUGASSERT(!up_interrupt_context());
+
+  /* Set irq flag */
+
+  up_set_interrupt_context(true);
 
   /* Deliver the IRQ */
 
   irq_dispatch(irq, regs);
   tcb = this_task();
 
-  /* Check for a context switch.  If a context switch occurred, then
-   * current_regs will have a different value than it did on entry.  If an
-   * interrupt level context switch has occurred, then restore the floating
-   * point state and the establish the correct address environment before
-   * returning from the interrupt.
-   */
+  /* Check for a context switch. */
 
   if (*running_task != tcb)
     {
@@ -129,11 +123,9 @@ uintreg_t *riscv_doirq(int irq, uintreg_t *regs)
       *running_task = tcb;
     }
 
-  /* Set current_regs to NULL to indicate that we are no longer in an
-   * interrupt handler.
-   */
+  /* Set irq flag */
 
-  up_set_current_regs(NULL);
+  up_set_interrupt_context(false);
 
 #endif
   board_autoled_off(LED_INIRQ);

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

@@ -112,22 +112,22 @@ int riscv_exception(int mcause, void *regs, void *args)
 
       /* Return to _exit function in privileged mode with argument SIGSEGV */
 
-      up_current_regs()[REG_EPC] = (uintptr_t)_exit;
-      up_current_regs()[REG_A0] = SIGSEGV;
-      up_current_regs()[REG_INT_CTX] |= STATUS_PPP;
+      running_regs()[REG_EPC] = _exit;
+      running_regs()[REG_A0] = (void *)SIGSEGV;
+      ((uintreg_t *)running_regs())[REG_INT_CTX] |= STATUS_PPP;
 
       /* Continue with kernel stack in use. The frame(s) in kernel stack
        * are no longer needed, so just set it to top
        */
 
-      up_current_regs()[REG_SP] = (uintptr_t)tcb->xcp.ktopstk;
+      running_regs()[REG_SP] = tcb->xcp.ktopstk;
     }
   else
 #endif
     {
       _alert("PANIC!!! Exception = %" PRIxREG "\n", cause);
       up_irq_save();
-      up_set_current_regs(regs);
+      up_set_interrupt_context(true);
       PANIC_WITH_REGS("panic", regs);
     }
 
@@ -199,7 +199,7 @@ int riscv_fillpage(int mcause, void *regs, void *args)
     {
       _alert("PANIC!!! virtual address not mappable: %" PRIxPTR "\n", vaddr);
       up_irq_save();
-      up_set_current_regs(regs);
+      up_set_interrupt_context(true);
       PANIC_WITH_REGS("panic", regs);
     }
 

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

@@ -34,7 +34,9 @@
  * Public Data
  ****************************************************************************/
 
-volatile uintreg_t *g_current_regs[CONFIG_SMP_NCPUS];
+/* g_interrupt_context store irq status */
+
+volatile bool g_interrupt_context[CONFIG_SMP_NCPUS];
 
 /****************************************************************************
  * Private Functions

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

@@ -55,7 +55,7 @@ uintptr_t up_getusrsp(void *regs)
 
 void up_dump_register(void *dumpregs)
 {
-  volatile uintreg_t *regs = dumpregs ? dumpregs : up_current_regs();
+  volatile uintreg_t *regs = dumpregs ? dumpregs : running_regs();
 
   /* Are user registers available from interrupt processing? */
 

arch/risc-v/src/common/supervisor/riscv_perform_syscall.c

@@ -47,9 +47,9 @@ void *riscv_perform_syscall(uintreg_t *regs)
       (*running_task)->xcp.regs = regs;
     }
 
-  /* Set up the interrupt register set needed by swint() */
+  /* Set irq flag */
 
-  up_set_current_regs(regs);
+  up_set_interrupt_context(true);
 
   /* Run the system call handler (swint) */
 
@@ -79,7 +79,9 @@ void *riscv_perform_syscall(uintreg_t *regs)
       *running_task = tcb;
     }
 
-  up_set_current_regs(NULL);
+  /* Set irq flag */
+
+  up_set_interrupt_context(false);
 
   return tcb->xcp.regs;
 }