*/
void exit_thread(void)
{
- struct task_struct *tsk = current;
- struct thread_struct *t = &tsk->thread;
-
/* The process may have allocated an io port bitmap... nuke it. */
- if (unlikely(NULL != t->io_bitmap_ptr)) {
+ if (unlikely(test_thread_flag(TIF_IO_BITMAP))) {
+ struct task_struct *tsk = current;
+ struct thread_struct *t = &tsk->thread;
int cpu = get_cpu();
struct tss_struct *tss = &per_cpu(init_tss, cpu);
kfree(t->io_bitmap_ptr);
t->io_bitmap_ptr = NULL;
+ clear_thread_flag(TIF_IO_BITMAP);
/*
* Careful, clear this in the TSS too:
*/
memset(tsk->thread.debugreg, 0, sizeof(unsigned long)*8);
memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array));
+ clear_tsk_thread_flag(tsk, TIF_DEBUG);
/*
* Forget coprocessor state..
*/
savesegment(gs,p->thread.gs);
tsk = current;
- if (unlikely(NULL != tsk->thread.io_bitmap_ptr)) {
+ if (unlikely(test_tsk_thread_flag(tsk, TIF_IO_BITMAP))) {
p->thread.io_bitmap_ptr = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL);
if (!p->thread.io_bitmap_ptr) {
p->thread.io_bitmap_max = 0;
}
memcpy(p->thread.io_bitmap_ptr, tsk->thread.io_bitmap_ptr,
IO_BITMAP_BYTES);
+ set_tsk_thread_flag(p, TIF_IO_BITMAP);
}
/*
return 1;
}
-static inline void
-handle_io_bitmap(struct thread_struct *next, struct tss_struct *tss)
+static noinline void __switch_to_xtra(struct task_struct *next_p,
+ struct tss_struct *tss)
{
- if (!next->io_bitmap_ptr) {
+ struct thread_struct *next;
+
+ next = &next_p->thread;
+
+ if (test_tsk_thread_flag(next_p, TIF_DEBUG)) {
+ set_debugreg(next->debugreg[0], 0);
+ set_debugreg(next->debugreg[1], 1);
+ set_debugreg(next->debugreg[2], 2);
+ set_debugreg(next->debugreg[3], 3);
+ /* no 4 and 5 */
+ set_debugreg(next->debugreg[6], 6);
+ set_debugreg(next->debugreg[7], 7);
+ }
+
+ if (!test_tsk_thread_flag(next_p, TIF_IO_BITMAP)) {
/*
* Disable the bitmap via an invalid offset. We still cache
* the previous bitmap owner and the IO bitmap contents:
tss->io_bitmap_base = INVALID_IO_BITMAP_OFFSET;
return;
}
+
if (likely(next == tss->io_bitmap_owner)) {
/*
* Previous owner of the bitmap (hence the bitmap content)
set_iopl_mask(next->iopl);
/*
- * Now maybe reload the debug registers
+ * Now maybe handle debug registers and/or IO bitmaps
*/
- if (unlikely(next->debugreg[7])) {
- set_debugreg(next->debugreg[0], 0);
- set_debugreg(next->debugreg[1], 1);
- set_debugreg(next->debugreg[2], 2);
- set_debugreg(next->debugreg[3], 3);
- /* no 4 and 5 */
- set_debugreg(next->debugreg[6], 6);
- set_debugreg(next->debugreg[7], 7);
- }
-
- if (unlikely(prev->io_bitmap_ptr || next->io_bitmap_ptr))
- handle_io_bitmap(next, tss);
+ if (unlikely((task_thread_info(next_p)->flags & _TIF_WORK_CTXSW)
+ || test_tsk_thread_flag(prev_p, TIF_IO_BITMAP)))
+ __switch_to_xtra(next_p, tss);
disable_tsc(prev_p, next_p);