diff options
Diffstat (limited to 'arch/x86/kernel/process_64.c')
| -rw-r--r-- | arch/x86/kernel/process_64.c | 45 |
1 files changed, 15 insertions, 30 deletions
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 3bd7e6eebf31..cfa5c90c01db 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -122,7 +122,7 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); while (!need_resched()) { rmb(); @@ -139,8 +139,14 @@ void cpu_idle(void) enter_idle(); /* Don't trace irqs off for idle */ stop_critical_timings(); + + /* enter_idle() needs rcu for notifiers */ + rcu_idle_enter(); + if (cpuidle_idle_call()) pm_idle(); + + rcu_idle_exit(); start_critical_timings(); /* In many cases the interrupt that ended idle @@ -149,7 +155,7 @@ void cpu_idle(void) __exit_idle(); } - tick_nohz_restart_sched_tick(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); @@ -280,6 +286,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, set_tsk_thread_flag(p, TIF_FORK); + p->fpu_counter = 0; p->thread.io_bitmap_ptr = NULL; savesegment(gs, p->thread.gsindex); @@ -293,13 +300,12 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps)); if (unlikely(test_tsk_thread_flag(me, TIF_IO_BITMAP))) { - p->thread.io_bitmap_ptr = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL); + p->thread.io_bitmap_ptr = kmemdup(me->thread.io_bitmap_ptr, + IO_BITMAP_BYTES, GFP_KERNEL); if (!p->thread.io_bitmap_ptr) { p->thread.io_bitmap_max = 0; return -ENOMEM; } - memcpy(p->thread.io_bitmap_ptr, me->thread.io_bitmap_ptr, - IO_BITMAP_BYTES); set_tsk_thread_flag(p, TIF_IO_BITMAP); } @@ -381,18 +387,9 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) int cpu = smp_processor_id(); struct tss_struct *tss = &per_cpu(init_tss, cpu); unsigned fsindex, gsindex; - bool preload_fpu; - - /* - * 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; + fpu_switch_t fpu; - /* 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, LDT and the page table pointer: @@ -422,13 +419,6 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) load_TLS(next, cpu); - /* Must be after DS reload */ - __unlazy_fpu(prev_p); - - /* Make sure cpu is ready for new context */ - if (preload_fpu) - clts(); - /* * Leave lazy mode, flushing any hypercalls made here. * This must be done before restoring TLS segments so @@ -469,6 +459,8 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) wrmsrl(MSR_KERNEL_GS_BASE, next->gs); prev->gsindex = gsindex; + switch_fpu_finish(next_p, fpu); + /* * Switch the PDA and FPU contexts. */ @@ -487,13 +479,6 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) task_thread_info(prev_p)->flags & _TIF_WORK_CTXSW_PREV)) __switch_to_xtra(prev_p, next_p, tss); - /* - * Preload the FPU context, now that we've determined that the - * task is likely to be using it. - */ - if (preload_fpu) - __math_state_restore(); - return prev_p; } |