From: Rik van Riel <r...@redhat.com>
Replace magic assignments of fpu.last_cpu = ~0 with more explicit
disable_task_lazy_fpu_restore calls.
This also fixes the lazy FPU restore disabling in drop_fpu, which
only really works when !use_eager_fpu(). This is fine for now,
because fpu_lazy_restore() is only used when !use_eager_fpu()
currently, but we may want to expand that.
Signed-off-by: Rik van Riel <r...@redhat.com>
---
arch/x86/include/asm/fpu-internal.h | 9 +++++----
arch/x86/kernel/i387.c | 2 +-
arch/x86/kernel/process.c | 2 +-
3 files changed, 7 insertions(+), 6 deletions(-)
diff --git a/arch/x86/include/asm/fpu-internal.h
b/arch/x86/include/asm/fpu-internal.h
index c1f66261ad12..e2832f9dfed5 100644
--- a/arch/x86/include/asm/fpu-internal.h
+++ b/arch/x86/include/asm/fpu-internal.h
@@ -396,7 +396,7 @@ static inline void drop_fpu(struct task_struct *tsk)
* Forget coprocessor state..
*/
preempt_disable();
- tsk->thread.fpu_counter = 0;
+ task_disable_lazy_fpu_restore(tsk);
__drop_fpu(tsk);
clear_used_math();
preempt_enable();
@@ -440,8 +440,9 @@ static inline fpu_switch_t switch_fpu_prepare(struct
task_struct *old, struct ta
new->thread.fpu_counter > 5);
if (__thread_has_fpu(old)) {
if (!__save_init_fpu(old))
- cpu = ~0;
- old->thread.fpu.last_cpu = cpu;
+ task_disable_lazy_fpu_restore(old);
+ else
+ old->thread.fpu.last_cpu = cpu;
old->thread.fpu.has_fpu = 0; /* But leave fpu_owner_task! */
/* Don't change CR0.TS if we just switch! */
@@ -453,7 +454,7 @@ static inline fpu_switch_t switch_fpu_prepare(struct
task_struct *old, struct ta
stts();
} else {
old->thread.fpu_counter = 0;
- old->thread.fpu.last_cpu = ~0;
+ task_disable_lazy_fpu_restore(old);
if (fpu.preload) {
new->thread.fpu_counter++;
if (!use_eager_fpu() && fpu_lazy_restore(new, cpu))
diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c
index 8e070a6c30e5..8416b5f85806 100644
--- a/arch/x86/kernel/i387.c
+++ b/arch/x86/kernel/i387.c
@@ -250,7 +250,7 @@ int init_fpu(struct task_struct *tsk)
if (tsk_used_math(tsk)) {
if (cpu_has_fpu && tsk == current)
unlazy_fpu(tsk);
- tsk->thread.fpu.last_cpu = ~0;
+ task_disable_lazy_fpu_restore(tsk);
return 0;
}
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index dd9a069a5ec5..83480373a642 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -68,8 +68,8 @@ int arch_dup_task_struct(struct task_struct *dst, struct
task_struct *src)
dst->thread.fpu_counter = 0;
dst->thread.fpu.has_fpu = 0;
- dst->thread.fpu.last_cpu = ~0;
dst->thread.fpu.state = NULL;
+ task_disable_lazy_fpu_restore(dst);
if (tsk_used_math(src)) {
int err = fpu_alloc(&dst->thread.fpu);
if (err)
--
1.9.3
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