diff options
Diffstat (limited to 'src/core/scheduler_asm.S')
| -rw-r--r-- | src/core/scheduler_asm.S | 28 |
1 files changed, 24 insertions, 4 deletions
diff --git a/src/core/scheduler_asm.S b/src/core/scheduler_asm.S index 1f916ec..2fdf3e5 100644 --- a/src/core/scheduler_asm.S +++ b/src/core/scheduler_asm.S @@ -5,6 +5,24 @@ // to this process task_switch: pop %esi + + // Switch to the new task kernel stack + mov 72(%esi), %ss + mov 76(%esi), %esp + + // If we where in kernel mode we should keep using the same + // stack which is stored in regs.ss and regs.esp by schedule + mov 24(%esi), %eax + cmp $0x08, %eax # Check if we were in kernel mode + jne skip_kernel_stack + mov 32(%esi), %ss + mov 36(%esi), %esp + skip_kernel_stack: + + // Setup process page directory to be able to use task stack + mov 4(%esi), %eax + mov %eax, %cr3 + push 8(%esi) # eax (cf PROC struct) push 12(%esi) # ebx push 16(%esi) # ecx @@ -20,10 +38,6 @@ task_switch: movb $0x20, %al outb %al, $0x20 - // Setup process page directory - mov 4(%esi), %eax - mov %eax, %cr3 - // Setup registers pop %gs pop %fs @@ -37,8 +51,14 @@ task_switch: pop %eax // Perform the task switch + push %eax + mov 24(%esi), %eax + cmp $0x08, %eax # Check if we were in kernel mode + pop %eax + je skip_stack push 32(%esi) # ss push 36(%esi) # esp + skip_stack: push 68(%esi) # eflags push 24(%esi) # cs push 28(%esi) # eip |