diff options
Diffstat (limited to 'arch/x86/kernel/fpu/core.c')
| -rw-r--r-- | arch/x86/kernel/fpu/core.c | 38 |
1 files changed, 25 insertions, 13 deletions
diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 779813126f49..9e7f9e7b2cca 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -236,14 +236,17 @@ static void fpu_copy(struct task_struct *dst, struct task_struct *src) int fpu__copy(struct task_struct *dst, struct task_struct *src) { + struct fpu *dst_fpu = &dst->thread.fpu; + struct fpu *src_fpu = &src->thread.fpu; + dst->thread.fpu.counter = 0; dst->thread.fpu.has_fpu = 0; dst->thread.fpu.state = NULL; task_disable_lazy_fpu_restore(dst); - if (src->flags & PF_USED_MATH) { - int err = fpstate_alloc(&dst->thread.fpu); + if (src_fpu->fpstate_active) { + int err = fpstate_alloc(dst_fpu); if (err) return err; @@ -260,11 +263,12 @@ int fpu__copy(struct task_struct *dst, struct task_struct *src) */ int fpstate_alloc_init(struct task_struct *curr) { + struct fpu *fpu = &curr->thread.fpu; int ret; if (WARN_ON_ONCE(curr != current)) return -EINVAL; - if (WARN_ON_ONCE(curr->flags & PF_USED_MATH)) + if (WARN_ON_ONCE(fpu->fpstate_active)) return -EINVAL; /* @@ -277,7 +281,7 @@ int fpstate_alloc_init(struct task_struct *curr) fpstate_init(&curr->thread.fpu); /* Safe to do for the current task: */ - curr->flags |= PF_USED_MATH; + fpu->fpstate_active = 1; return 0; } @@ -308,12 +312,13 @@ EXPORT_SYMBOL_GPL(fpstate_alloc_init); */ static int fpu__unlazy_stopped(struct task_struct *child) { + struct fpu *child_fpu = &child->thread.fpu; int ret; if (WARN_ON_ONCE(child == current)) return -EINVAL; - if (child->flags & PF_USED_MATH) { + if (child_fpu->fpstate_active) { task_disable_lazy_fpu_restore(child); return 0; } @@ -328,7 +333,7 @@ static int fpu__unlazy_stopped(struct task_struct *child) fpstate_init(&child->thread.fpu); /* Safe to do for stopped child tasks: */ - child->flags |= PF_USED_MATH; + child_fpu->fpstate_active = 1; return 0; } @@ -348,7 +353,7 @@ void fpu__restore(void) struct task_struct *tsk = current; struct fpu *fpu = &tsk->thread.fpu; - if (!(tsk->flags & PF_USED_MATH)) { + if (!fpu->fpstate_active) { local_irq_enable(); /* * does a slab alloc which can sleep @@ -378,6 +383,8 @@ EXPORT_SYMBOL_GPL(fpu__restore); void fpu__flush_thread(struct task_struct *tsk) { + struct fpu *fpu = &tsk->thread.fpu; + WARN_ON(tsk != current); if (!use_eager_fpu()) { @@ -385,7 +392,7 @@ void fpu__flush_thread(struct task_struct *tsk) drop_fpu(tsk); fpstate_free(&tsk->thread.fpu); } else { - if (!(tsk->flags & PF_USED_MATH)) { + if (!fpu->fpstate_active) { /* kthread execs. TODO: cleanup this horror. */ if (WARN_ON(fpstate_alloc_init(tsk))) force_sig(SIGKILL, tsk); @@ -402,12 +409,16 @@ void fpu__flush_thread(struct task_struct *tsk) */ int fpregs_active(struct task_struct *target, const struct user_regset *regset) { - return (target->flags & PF_USED_MATH) ? regset->n : 0; + struct fpu *target_fpu = &target->thread.fpu; + + return target_fpu->fpstate_active ? regset->n : 0; } int xfpregs_active(struct task_struct *target, const struct user_regset *regset) { - return (cpu_has_fxsr && (target->flags & PF_USED_MATH)) ? regset->n : 0; + struct fpu *target_fpu = &target->thread.fpu; + + return (cpu_has_fxsr && target_fpu->fpstate_active) ? regset->n : 0; } int xfpregs_get(struct task_struct *target, const struct user_regset *regset, @@ -733,16 +744,17 @@ int fpregs_set(struct task_struct *target, const struct user_regset *regset, * struct user_i387_struct) but is in fact only used for 32-bit * dumps, so on 64-bit it is really struct user_i387_ia32_struct. */ -int dump_fpu(struct pt_regs *regs, struct user_i387_struct *fpu) +int dump_fpu(struct pt_regs *regs, struct user_i387_struct *ufpu) { struct task_struct *tsk = current; + struct fpu *fpu = &tsk->thread.fpu; int fpvalid; - fpvalid = !!(tsk->flags & PF_USED_MATH); + fpvalid = fpu->fpstate_active; if (fpvalid) fpvalid = !fpregs_get(tsk, NULL, 0, sizeof(struct user_i387_ia32_struct), - fpu, NULL); + ufpu, NULL); return fpvalid; } |