refactor: Optimize the context switch overhead

[lunaix-os.git] / lunaix-os / kernel / k_init.c

diff --git a/lunaix-os/kernel/k_init.c b/lunaix-os/kernel/k_init.c
index d399251960ee6421354c28d4d6a273f837a40d79..8c40b6b1df8953e7889ae8becb053729d69b8b42 100644 (file)
--- a/lunaix-os/kernel/k_init.c
+++ b/lunaix-os/kernel/k_init.c
@@ -126,10 +126,6 @@ spawn_proc0()
      * 目前的解决方案是2
      */
 
-    proc0->intr_ctx = (isr_param){ .registers = { .ds = KDATA_SEG,
-                                                  .es = KDATA_SEG,
-                                                  .fs = KDATA_SEG,
-                                                  .gs = KDATA_SEG } };
     proc0->parent = proc0;
 
     // 方案1：必须在读取eflags之后禁用。否则当进程被调度时，中断依然是关闭的！
@@ -141,7 +137,7 @@ spawn_proc0()
     proc0->page_table = vmm_dup_vmspace(proc0->pid);
 
     // 直接切换到新的拷贝，进行配置。
-    cpu_lcr3(proc0->page_table);
+    cpu_ldvmspace(proc0->page_table);
 
     // 为内核创建一个专属栈空间。
     for (size_t i = 0; i < (KSTACK_SIZE >> PG_SIZE_BITS); i++) {
@@ -155,12 +151,19 @@ spawn_proc0()
 
     struct exec_param* execp =
       (struct exec_param*)(KSTACK_TOP - sizeof(struct exec_param));
+    isr_param* isrp = (isr_param*)((ptr_t)execp - sizeof(isr_param));
 
     *execp = (struct exec_param){ .cs = KCODE_SEG,
                                   .eip = (ptr_t)__proc0,
                                   .ss = KDATA_SEG,
                                   .eflags = cpu_reflags() };
-    proc0->intr_ctx.execp = execp;
+    *isrp = (isr_param){ .registers = { .ds = KDATA_SEG,
+                                        .es = KDATA_SEG,
+                                        .fs = KDATA_SEG,
+                                        .gs = KDATA_SEG },
+                         .execp = execp };
+
+    proc0->intr_ctx = isrp;
 
     // 加载x87默认配置
     asm volatile("fninit\n"
@@ -179,9 +182,6 @@ spawn_proc0()
     assert_msg(0, "Unexpected Return");
 }
 
-extern u8_t __usrtext_start;
-extern u8_t __usrtext_end;
-
 // 按照 Memory map 标识可用的物理页
 void
 setup_memory(multiboot_memory_map_t* map, size_t map_size)
@@ -202,11 +202,6 @@ setup_memory(multiboot_memory_map_t* map, size_t map_size)
     size_t pg_count = V2P(&__kernel_end) >> PG_SIZE_BITS;
     pmm_mark_chunk_occupied(KERNEL_PID, 0, pg_count, PP_FGLOCKED);
 
-    for (ptr_t i = (ptr_t)&__usrtext_start; i < (ptr_t)&__usrtext_end;
-         i += PG_SIZE) {
-        vmm_set_mapping(VMS_SELF, i, V2P(i), PG_PREM_UR, VMAP_NULL);
-    }
-
     // reserve higher half
     for (size_t i = L1_INDEX(KERNEL_MM_BASE); i < 1023; i++) {
         assert(vmm_set_mapping(VMS_SELF, i << 22, 0, 0, VMAP_NOMAP));