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-rw-r--r--arch/x86/kernel/process_32.c89
1 files changed, 7 insertions, 82 deletions
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index 485204f58cd..ae6847303e2 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -9,7 +9,6 @@
* This file handles the architecture-dependent parts of process handling..
*/
-#include <linux/stackprotector.h>
#include <linux/cpu.h>
#include <linux/errno.h>
#include <linux/sched.h>
@@ -31,20 +30,18 @@
#include <linux/kallsyms.h>
#include <linux/ptrace.h>
#include <linux/personality.h>
-#include <linux/tick.h>
#include <linux/percpu.h>
#include <linux/prctl.h>
#include <linux/ftrace.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#include <linux/kdebug.h>
-#include <linux/cpuidle.h>
#include <asm/pgtable.h>
-#include <asm/system.h>
#include <asm/ldt.h>
#include <asm/processor.h>
#include <asm/i387.h>
+#include <asm/fpu-internal.h>
#include <asm/desc.h>
#ifdef CONFIG_MATH_EMULATION
#include <asm/math_emu.h>
@@ -57,7 +54,7 @@
#include <asm/idle.h>
#include <asm/syscalls.h>
#include <asm/debugreg.h>
-#include <asm/nmi.h>
+#include <asm/switch_to.h>
asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
@@ -69,62 +66,6 @@ unsigned long thread_saved_pc(struct task_struct *tsk)
return ((unsigned long *)tsk->thread.sp)[3];
}
-#ifndef CONFIG_SMP
-static inline void play_dead(void)
-{
- BUG();
-}
-#endif
-
-/*
- * The idle thread. There's no useful work to be
- * done, so just try to conserve power and have a
- * low exit latency (ie sit in a loop waiting for
- * somebody to say that they'd like to reschedule)
- */
-void cpu_idle(void)
-{
- int cpu = smp_processor_id();
-
- /*
- * If we're the non-boot CPU, nothing set the stack canary up
- * for us. CPU0 already has it initialized but no harm in
- * doing it again. This is a good place for updating it, as
- * we wont ever return from this function (so the invalid
- * canaries already on the stack wont ever trigger).
- */
- boot_init_stack_canary();
-
- current_thread_info()->status |= TS_POLLING;
-
- /* endless idle loop with no priority at all */
- while (1) {
- tick_nohz_idle_enter();
- rcu_idle_enter();
- while (!need_resched()) {
-
- check_pgt_cache();
- rmb();
-
- if (cpu_is_offline(cpu))
- play_dead();
-
- local_touch_nmi();
- local_irq_disable();
- /* Don't trace irqs off for idle */
- stop_critical_timings();
- if (cpuidle_idle_call())
- pm_idle();
- start_critical_timings();
- }
- rcu_idle_exit();
- tick_nohz_idle_exit();
- preempt_enable_no_resched();
- schedule();
- preempt_disable();
- }
-}
-
void __show_regs(struct pt_regs *regs, int all)
{
unsigned long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L;
@@ -214,6 +155,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
task_user_gs(p) = get_user_gs(regs);
+ p->fpu_counter = 0;
p->thread.io_bitmap_ptr = NULL;
tsk = current;
err = -ENOMEM;
@@ -299,22 +241,11 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
*next = &next_p->thread;
int cpu = smp_processor_id();
struct tss_struct *tss = &per_cpu(init_tss, cpu);
- bool preload_fpu;
+ fpu_switch_t fpu;
/* never put a printk in __switch_to... printk() calls wake_up*() indirectly */
- /*
- * If the task has used fpu the last 5 timeslices, just do a full
- * restore of the math state immediately to avoid the trap; the
- * chances of needing FPU soon are obviously high now
- */
- preload_fpu = tsk_used_math(next_p) && next_p->fpu_counter > 5;
-
- __unlazy_fpu(prev_p);
-
- /* we're going to use this soon, after a few expensive things */
- if (preload_fpu)
- prefetch(next->fpu.state);
+ fpu = switch_fpu_prepare(prev_p, next_p, cpu);
/*
* Reload esp0.
@@ -354,11 +285,6 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
task_thread_info(next_p)->flags & _TIF_WORK_CTXSW_NEXT))
__switch_to_xtra(prev_p, next_p, tss);
- /* If we're going to preload the fpu context, make sure clts
- is run while we're batching the cpu state updates. */
- if (preload_fpu)
- clts();
-
/*
* Leave lazy mode, flushing any hypercalls made here.
* This must be done before restoring TLS segments so
@@ -368,15 +294,14 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
*/
arch_end_context_switch(next_p);
- if (preload_fpu)
- __math_state_restore();
-
/*
* Restore %gs if needed (which is common)
*/
if (prev->gs | next->gs)
lazy_load_gs(next->gs);
+ switch_fpu_finish(next_p, fpu);
+
percpu_write(current_task, next_p);
return prev_p;