]> git.saurik.com Git - apple/xnu.git/blobdiff - osfmk/i386/cswitch.s
xnu-792.24.17.tar.gz
[apple/xnu.git] / osfmk / i386 / cswitch.s
index 31ca053b8fb4c303db3787e0089c5de385e4cd60..107bc26afb3ce82845eaf5f252a7dc7d1493576a 100644 (file)
@@ -66,7 +66,6 @@
 
 #define        CX(addr, reg)   addr(,reg,4)
 
-       .text
 /*
  * Context switch routines for i386.
  */
@@ -87,27 +86,23 @@ Entry(Load_context)
        call    EXT(thread_continue)
 
 /*
- *     This has to save registers only
+ *     This really only has to save registers
  *     when there is no explicit continuation.
  */
 
 Entry(Switch_context)
-       popl    %eax                            /* pop return PC */
+       movl    %gs:CPU_ACTIVE_STACK,%ecx /* get old kernel stack */
 
-       /* Test for a continuation and skip all state saving if so... */
-       cmpl    $0,4(%esp)
-       jne     5f
-       movl    %gs:CPU_ACTIVE_STACK,%ecx       /* get old kernel stack */
        movl    %ebx,KSS_EBX(%ecx)              /* save registers */
        movl    %ebp,KSS_EBP(%ecx)
        movl    %edi,KSS_EDI(%ecx)
        movl    %esi,KSS_ESI(%ecx)
-       movl    %eax,KSS_EIP(%ecx)              /* save return PC */
+       popl    KSS_EIP(%ecx)                   /* save return PC */
        movl    %esp,KSS_ESP(%ecx)              /* save SP */
-5:
+
        movl    0(%esp),%eax                    /* return old thread */
        movl    8(%esp),%ebx                    /* get new thread */
-       movl    %ebx,%gs:CPU_ACTIVE_THREAD      /* new thread is active */
+       movl    %ebx,%gs:CPU_ACTIVE_THREAD                /* new thread is active */
        movl    TH_KERNEL_STACK(%ebx),%ecx      /* get its kernel stack */
        lea     KERNEL_STACK_SIZE-IKS_SIZE-IEL_SIZE(%ecx),%ebx
                                                /* point to stack top */
@@ -115,7 +110,9 @@ Entry(Switch_context)
        movl    %ecx,%gs:CPU_ACTIVE_STACK       /* set current stack */
        movl    %ebx,%gs:CPU_KERNEL_STACK       /* set stack top */
 
-       
+
+       movl    $0,%gs:CPU_ACTIVE_KLOADED
+
        movl    KSS_ESP(%ecx),%esp              /* switch stacks */
        movl    KSS_ESI(%ecx),%esi              /* restore registers */
        movl    KSS_EDI(%ecx),%edi
@@ -129,17 +126,19 @@ Entry(Thread_continue)
        call    *%ebx                           /* call real continuation */
 
 /*
- * thread_t Shutdown_context(thread_t thread,
- *                      void (*routine)(processor_t),
- *                      processor_t processor)
+ * void machine_processor_shutdown(thread_t thread,
+ *                                void (*routine)(processor_t),
+ *                                processor_t processor)
  *
  * saves the kernel context of the thread,
  * switches to the interrupt stack,
  * continues the thread (with thread_continue),
  * then runs routine on the interrupt stack.
  *
+ * Assumes that the thread is a kernel thread (thus
+ * has no FPU state)
  */
-Entry(Shutdown_context)
+Entry(machine_processor_shutdown)
        movl    %gs:CPU_ACTIVE_STACK,%ecx /* get old kernel stack */
        movl    %ebx,KSS_EBX(%ecx)              /* save registers */
        movl    %ebp,KSS_EBP(%ecx)
@@ -158,3 +157,10 @@ Entry(Shutdown_context)
        pushl   %esi                            /* push argument */
        call    *%ebx                           /* call routine to run */
        hlt                                     /* (should never return) */
+
+
+        .text
+
+       .globl  EXT(locore_end)
+LEXT(locore_end)
+