[PATCH 057/208] x86/fpu: Use 'struct fpu' in fpu_lazy_restore()

Ingo Molnar
2015-05-05T16:29:20Z

Also rename it to fpu_want_lazy_restore(), to better indicate that
this function just tests whether we can do a lazy restore. (The old
name suggested that it was doing the lazy restore, which is not
the case.)

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/x86/include/asm/fpu-internal.h | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/arch/x86/include/asm/fpu-internal.h b/arch/x86/include/asm/fpu-internal.h
index 76a1f3529881..3f6d36c6ffce 100644
--- a/arch/x86/include/asm/fpu-internal.h
+++ b/arch/x86/include/asm/fpu-internal.h
@@ -74,10 +74,9 @@ static inline void __cpu_disable_lazy_restore(unsigned int cpu)
per_cpu(fpu_fpregs_owner_ctx, cpu) = NULL;
}

-static inline int fpu_lazy_restore(struct task_struct *new, unsigned int cpu)
+static inline int fpu_want_lazy_restore(struct fpu *fpu, unsigned int cpu)
{
- return &new->thread.fpu == this_cpu_read_stable(fpu_fpregs_owner_ctx) &&
- cpu == new->thread.fpu.last_cpu;
+ return fpu == this_cpu_read_stable(fpu_fpregs_owner_ctx) && cpu == fpu->last_cpu;
}

static inline int is_ia32_compat_frame(void)
@@ -439,7 +438,7 @@ static inline fpu_switch_t switch_fpu_prepare(struct task_struct *old, struct ta
old->thread.fpu.last_cpu = -1;
if (fpu.preload) {
new->thread.fpu.counter++;
- if (fpu_lazy_restore(new, cpu))
+ if (fpu_want_lazy_restore(new_fpu, cpu))
fpu.preload = 0;
else
prefetch(new->thread.fpu.state);
--
2.1.0