arch/arm: syscall SYS_switch_context and SYS_restore_context use 0 para

reason: simplify context switch sys_call0(SYS_switch_context) sys_call0(SYS_restore_context) Signed-off-by: hujun5 <[email protected]>
apache · Nov 21, 2024 · e120df4 · e120df4
1 parent 9cd0ea3
commit e120df4
Show file tree

Hide file tree

Showing 17 changed files with 56 additions and 324 deletions.
diff --git a/arch/arm/include/irq.h b/arch/arm/include/irq.h
@@ -82,13 +82,13 @@
 #ifndef __ASSEMBLY__
 
 #ifndef up_switch_context
-#define up_switch_context(tcb, rtcb)                              \
-  do {                                                            \
-    if (!up_interrupt_context())                                  \
-      {                                                           \
-        sys_call2(SYS_switch_context, (uintptr_t)&rtcb->xcp.regs, \
-                  (uintptr_t)tcb->xcp.regs);                      \
-      }                                                           \
+#define up_switch_context(tcb, rtcb)   \
+  do {                                 \
+    if (!up_interrupt_context())       \
+      {                                \
+        sys_call0(SYS_switch_context); \
+      }                                \
+      UNUSED(rtcb);                    \
   } while (0)
 #endif
 

diff --git a/arch/arm/src/arm/arm_sigdeliver.c b/arch/arm/src/arm/arm_sigdeliver.c
@@ -54,7 +54,6 @@
 void arm_sigdeliver(void)
 {
   struct tcb_s *rtcb = this_task();
-  uint32_t *regs = rtcb->xcp.saved_regs;
 
   board_autoled_on(LED_SIGNAL);
 
@@ -99,5 +98,6 @@ void arm_sigdeliver(void)
   board_autoled_off(LED_SIGNAL);
 
   g_running_tasks[this_cpu()] = NULL;
-  arm_fullcontextrestore(regs);
+  rtcb->xcp.regs = rtcb->xcp.saved_regs;
+  arm_fullcontextrestore(rtcb);
 }
diff --git a/arch/arm/src/arm/arm_syscall.c b/arch/arm/src/arm/arm_syscall.c
@@ -81,46 +81,7 @@ uint32_t *arm_syscall(uint32_t *regs)
 
   switch (cmd)
     {
-      /* R0=SYS_restore_context:  Restore task context
-       *
-       * void arm_fullcontextrestore(uint32_t *restoreregs)
-       *   noreturn_function;
-       *
-       * At this point, the following values are saved in context:
-       *
-       *   R0 = SYS_restore_context
-       *   R1 = restoreregs
-       */
-
       case SYS_restore_context:
-        {
-          /* Replace 'regs' with the pointer to the register set in
-           * regs[REG_R1].  On return from the system call, that register
-           * set will determine the restored context.
-           */
-
-          tcb->xcp.regs = (uint32_t *)regs[REG_R1];
-          DEBUGASSERT(up_current_regs());
-        }
-        break;
-
-      /* R0=SYS_switch_context:  This a switch context command:
-       *
-       *   void arm_switchcontext(uint32_t **saveregs,
-       *                          uint32_t *restoreregs);
-       *
-       * At this point, the following values are saved in context:
-       *
-       *   R0 = SYS_switch_context
-       *   R1 = saveregs
-       *   R2 = restoreregs
-       *
-       * In this case, we do both: We save the context registers to the save
-       * register area reference by the saved contents of R1 and then set
-       * regs to the save register area referenced by the saved
-       * contents of R2.
-       */
-
       case SYS_switch_context:
         break;
 

diff --git a/arch/arm/src/armv6-m/arm_sigdeliver.c b/arch/arm/src/armv6-m/arm_sigdeliver.c
@@ -54,9 +54,10 @@
 void arm_sigdeliver(void)
 {
   struct tcb_s *rtcb = this_task();
-  uint32_t *regs = rtcb->xcp.saved_regs;
 
 #ifdef CONFIG_SMP
+  uint32_t *regs = rtcb->xcp.saved_regs;
+
   /* In the SMP case, we must terminate the critical section while the signal
    * handler executes, but we also need to restore the irqcount when the
    * we resume the main thread of the task.
@@ -162,5 +163,7 @@ void arm_sigdeliver(void)
   leave_critical_section((uint16_t)regs[REG_PRIMASK]);
   rtcb->irqcount--;
 #endif
-  arm_fullcontextrestore(regs);
+  g_running_tasks[this_cpu()] = NULL;
+  rtcb->xcp.regs = rtcb->xcp.saved_regs;
+  arm_fullcontextrestore(rtcb);
 }
diff --git a/arch/arm/src/armv6-m/arm_svcall.c b/arch/arm/src/armv6-m/arm_svcall.c
@@ -117,9 +117,8 @@ static void dispatch_syscall(void)
 
 int arm_svcall(int irq, void *context, void *arg)
 {
-  struct tcb_s *tcb = this_task();
   uint32_t *regs = (uint32_t *)context;
-  uint32_t *new_regs = regs;
+  bool need_switch = false;
   uint32_t cmd;
 
   cmd = regs[REG_R0];
@@ -149,51 +148,10 @@ int arm_svcall(int irq, void *context, void *arg)
 
   switch (cmd)
     {
-      /* R0=SYS_restore_context:  This a restore context command:
-       *
-       *   void arm_fullcontextrestore(uint32_t *restoreregs)
-       *     noreturn_function;
-       *
-       * At this point, the following values are saved in context:
-       *
-       *   R0 = SYS_restore_context
-       *   R1 = restoreregs
-       *
-       * In this case, we simply need to set current_regs to restore register
-       * area referenced in the saved R1. context == current_regs is the
-       * normal exception return.  By setting current_regs = context[R1], we
-       * force the return to the saved context referenced in R1.
-       */
-
       case SYS_restore_context:
-        {
-          DEBUGASSERT(regs[REG_R1] != 0);
-          new_regs = (uint32_t *)regs[REG_R1];
-          tcb->xcp.regs = (uint32_t *)regs[REG_R1];
-        }
-        break;
-
-      /* R0=SYS_switch_context:  This a switch context command:
-       *
-       *   void arm_switchcontext(uint32_t **saveregs,
-       *                          uint32_t *restoreregs);
-       *
-       * At this point, the following values are saved in context:
-       *
-       *   R0 = SYS_switch_context
-       *   R1 = saveregs
-       *   R2 = restoreregs
-       *
-       * In this case, we do both: We save the context registers to the save
-       * register area reference by the saved contents of R1 and then set
-       * current_regs to the save register area referenced by the saved
-       * contents of R2.
-       */
-
       case SYS_switch_context:
         {
-          DEBUGASSERT(regs[REG_R1] != 0 && regs[REG_R2] != 0);
-          new_regs = (uint32_t *)regs[REG_R2];
+          need_switch = true;
         }
         break;
 
@@ -447,12 +405,12 @@ int arm_svcall(int irq, void *context, void *arg)
    * switch.
    */
 
-  if (regs != new_regs)
+  if (need_switch)
     {
-      restore_critical_section(tcb, this_cpu());
+      restore_critical_section(this_task(), this_cpu());
 
 #ifdef CONFIG_DEBUG_SYSCALL_INFO
-      regs = new_regs;
+      regs = this_task()->xcp.regs;
 
       svcinfo("SVCall Return:\n");
       svcinfo("  R0: %08x %08x %08x %08x %08x %08x %08x %08x\n",

diff --git a/arch/arm/src/armv7-a/arm_sigdeliver.c b/arch/arm/src/armv7-a/arm_sigdeliver.c
@@ -54,9 +54,10 @@
 void arm_sigdeliver(void)
 {
   struct tcb_s *rtcb = this_task();
-  uint32_t *regs = rtcb->xcp.saved_regs;
 
 #ifdef CONFIG_SMP
+  uint32_t *regs = rtcb->xcp.saved_regs;
+
   /* In the SMP case, we must terminate the critical section while the signal
    * handler executes, but we also need to restore the irqcount when the
    * we resume the main thread of the task.
@@ -162,5 +163,6 @@ void arm_sigdeliver(void)
 #endif
 
   g_running_tasks[this_cpu()] = NULL;
-  arm_fullcontextrestore(regs);
+  rtcb->xcp.regs = rtcb->xcp.saved_regs;
+  arm_fullcontextrestore(rtcb);
 }
diff --git a/arch/arm/src/armv7-a/arm_syscall.c b/arch/arm/src/armv7-a/arm_syscall.c
@@ -257,47 +257,7 @@ uint32_t *arm_syscall(uint32_t *regs)
         }
         break;
 #endif
-
-      /* R0=SYS_restore_context:  Restore task context
-       *
-       * void arm_fullcontextrestore(uint32_t *restoreregs)
-       *   noreturn_function;
-       *
-       * At this point, the following values are saved in context:
-       *
-       *   R0 = SYS_restore_context
-       *   R1 = restoreregs
-       */
-
       case SYS_restore_context:
-        {
-          /* Replace 'regs' with the pointer to the register set in
-           * regs[REG_R1].  On return from the system call, that register
-           * set will determine the restored context.
-           */
-
-          tcb->xcp.regs = (uint32_t *)regs[REG_R1];
-          DEBUGASSERT(up_current_regs());
-        }
-        break;
-
-      /* R0=SYS_switch_context:  This a switch context command:
-       *
-       *   void arm_switchcontext(uint32_t **saveregs,
-       *                          uint32_t *restoreregs);
-       *
-       * At this point, the following values are saved in context:
-       *
-       *   R0 = SYS_switch_context
-       *   R1 = saveregs
-       *   R2 = restoreregs
-       *
-       * In this case, we do both: We save the context registers to the save
-       * register area reference by the saved contents of R1 and then set
-       * regs to the save register area referenced by the saved
-       * contents of R2.
-       */
-
       case SYS_switch_context:
         break;
 

diff --git a/arch/arm/src/armv7-m/arm_sigdeliver.c b/arch/arm/src/armv7-m/arm_sigdeliver.c
@@ -54,9 +54,10 @@
 void arm_sigdeliver(void)
 {
   struct tcb_s *rtcb = this_task();
-  uint32_t *regs = rtcb->xcp.saved_regs;
 
 #ifdef CONFIG_SMP
+  uint32_t *regs = rtcb->xcp.saved_regs;
+
   /* In the SMP case, we must terminate the critical section while the signal
    * handler executes, but we also need to restore the irqcount when the
    * we resume the main thread of the task.
@@ -174,5 +175,8 @@ void arm_sigdeliver(void)
 #endif
   rtcb->irqcount--;
 #endif
-  arm_fullcontextrestore(regs);
+
+  g_running_tasks[this_cpu()] = NULL;
+  rtcb->xcp.regs = rtcb->xcp.saved_regs;
+  arm_fullcontextrestore(rtcb);
 }
diff --git a/arch/arm/src/armv7-m/arm_svcall.c b/arch/arm/src/armv7-m/arm_svcall.c
@@ -125,9 +125,8 @@ static void dispatch_syscall(void)
 
 int arm_svcall(int irq, void *context, void *arg)
 {
-  struct tcb_s *tcb = this_task();
   uint32_t *regs = (uint32_t *)context;
-  uint32_t *new_regs = regs;
+  bool need_switch = false;
   uint32_t cmd;
 
   cmd = regs[REG_R0];
@@ -157,52 +156,10 @@ int arm_svcall(int irq, void *context, void *arg)
 
   switch (cmd)
     {
-      /* R0=SYS_restore_context:  This a restore context command:
-       *
-       *   void arm_fullcontextrestore(uint32_t *restoreregs)
-       *          noreturn_function;
-       *
-       * At this point, the following values are saved in context:
-       *
-       *   R0 = SYS_restore_context
-       *   R1 = restoreregs
-       *
-       * In this case, we simply need to set current_regs to restore
-       * register area referenced in the saved R1. context == current_regs
-       * is the normal exception return.  By setting current_regs =
-       * context[R1], we force the return to the saved context referenced
-       * in R1.
-       */
-
       case SYS_restore_context:
-        {
-          DEBUGASSERT(regs[REG_R1] != 0);
-          new_regs = (uint32_t *)regs[REG_R1];
-          tcb->xcp.regs = (uint32_t *)regs[REG_R1];
-        }
-        break;
-
-      /* R0=SYS_switch_context:  This a switch context command:
-       *
-       *   void arm_switchcontext(uint32_t **saveregs,
-       *                          uint32_t *restoreregs);
-       *
-       * At this point, the following values are saved in context:
-       *
-       *   R0 = SYS_switch_context
-       *   R1 = saveregs
-       *   R2 = restoreregs
-       *
-       * In this case, we do both: We save the context registers to the save
-       * register area reference by the saved contents of R1 and then set
-       * current_regs to the save register area referenced by the saved
-       * contents of R2.
-       */
-
       case SYS_switch_context:
         {
-          DEBUGASSERT(regs[REG_R1] != 0 && regs[REG_R2] != 0);
-          new_regs = (uint32_t *)regs[REG_R2];
+          need_switch = true;
         }
         break;
 
@@ -457,12 +414,12 @@ int arm_svcall(int irq, void *context, void *arg)
    * switch.
    */
 
-  if (regs != new_regs)
+  if (need_switch)
     {
-      restore_critical_section(tcb, this_cpu());
+      restore_critical_section(this_task(), this_cpu());
 
 #ifdef CONFIG_DEBUG_SYSCALL_INFO
-      regs = new_regs;
+      regs = this_task()->xcp.regs;
 
       svcinfo("SVCall Return:\n");
       svcinfo("  R0: %08x %08x %08x %08x %08x %08x %08x %08x\n",

diff --git a/arch/arm/src/armv7-r/arm_sigdeliver.c b/arch/arm/src/armv7-r/arm_sigdeliver.c
@@ -54,9 +54,10 @@
 void arm_sigdeliver(void)
 {
   struct tcb_s *rtcb = this_task();
-  uint32_t *regs = rtcb->xcp.saved_regs;
 
 #ifdef CONFIG_SMP
+  uint32_t *regs = rtcb->xcp.saved_regs;
+
   /* In the SMP case, we must terminate the critical section while the signal
    * handler executes, but we also need to restore the irqcount when the
    * we resume the main thread of the task.
@@ -159,5 +160,6 @@ void arm_sigdeliver(void)
 #endif
 
   g_running_tasks[this_cpu()] = NULL;
-  arm_fullcontextrestore(regs);
+  rtcb->xcp.regs = rtcb->xcp.saved_regs;
+  arm_fullcontextrestore(rtcb);
 }