X-Git-Url: https://scm.lunaixsky.com/lunaix-os.git/blobdiff_plain/94a87fe25c5ec021daf16edd64058ed6a37aba7d..61bcf0c65dac58d2f29ab40e016489c89ec8eec0:/lunaix-os/kernel/asm/x86/interrupt.S

diff --git a/lunaix-os/kernel/asm/x86/interrupt.S b/lunaix-os/kernel/asm/x86/interrupt.S
index 62c9ec5..cd3f547 100644
--- a/lunaix-os/kernel/asm/x86/interrupt.S
+++ b/lunaix-os/kernel/asm/x86/interrupt.S
@@ -104,10 +104,11 @@
 
         call intr_handler
 
+        movl (%esp), %eax
+
     .global soft_iret
     soft_iret:
-        cli
-        popl %esp
+        movl %eax, %esp
 
         popl %eax
         popl %ebx
@@ -134,11 +135,39 @@
 #endif
         iret
 
+    .global switch_to
+    switch_to:
+        # 约定
+        # arg1: 目标进程PCB地址 (next)
+        popl %ecx               # next
+
+        call signal_dispatch    # kernel/signal.c
+        movl %eax, %edx
+
+        movl __current, %eax    
+        movl 88(%eax), %ebx     # __current->pagetable
+        movl 88(%ecx), %eax     # next->pagetable
+        
+        cmpl %ebx, %eax         # if(next->pagtable != __current->pagetable) {
+        jz 1f
+        movl %eax, %cr3         #   cpu_lcr3(next->pagetable)
+                                # }
+    1:
+        movl %ecx, __current    # __current = next
+
+        test %edx, %edx         # do we have signal to handle?
+        jz 1f
+        movl %edx, %eax
+        jmp handle_signal
+    1:
+        leal 8(%ecx), %eax
+        jmp soft_iret
+
+    .global handle_signal
     handle_signal:
         # 注意1：任何对proc_sig的布局改动，都须及时的保证这里的一致性！
         # 注意2：handle_signal在调用之前，须确保proc_sig已经写入用户栈！
-        popl %eax               # arg1: addr of proc_sig structure in user stack
-        leal 8(%eax), %ebx
+        leal 8(%eax), %ebx      # arg1 in %eax: addr of proc_sig structure in user stack
 
         pushl 72(%ebx)          # proc_sig->prev_context.ss
         pushl %eax              # esp