[PATCH 061/208] x86/fpu: Use 'struct fpu' in switch_fpu_finish()

Ingo Molnar
2015-05-05T16:51:32Z

Migrate this function to pure 'struct fpu' usage.

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 | 6 ++----
arch/x86/kernel/process_32.c | 10 ++++++----
arch/x86/kernel/process_64.c | 8 +++++---
3 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/arch/x86/include/asm/fpu-internal.h b/arch/x86/include/asm/fpu-internal.h
index 60d2c6f376f3..5fd9b3f9be0f 100644
--- a/arch/x86/include/asm/fpu-internal.h
+++ b/arch/x86/include/asm/fpu-internal.h
@@ -451,11 +451,9 @@ switch_fpu_prepare(struct fpu *old_fpu, struct fpu *new_fpu, int cpu)
* state - all we need to do is to conditionally restore the register
* state itself.
*/
-static inline void switch_fpu_finish(struct task_struct *new, fpu_switch_t fpu)
+static inline void switch_fpu_finish(struct fpu *new_fpu, fpu_switch_t fpu_switch)
{
- struct fpu *new_fpu = &new->thread.fpu;
-
- if (fpu.preload) {
+ if (fpu_switch.preload) {
if (unlikely(restore_fpu_checking(new_fpu)))
fpu_reset_state(new_fpu);
}
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index 5b0ed71dde60..7adc314b5075 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -241,14 +241,16 @@ __visible __notrace_funcgraph struct task_struct *
__switch_to(struct task_struct *prev_p, struct task_struct *next_p)
{
struct thread_struct *prev = &prev_p->thread,
- *next = &next_p->thread;
+ *next = &next_p->thread;
+ struct fpu *prev_fpu = &prev->fpu;
+ struct fpu *next_fpu = &next->fpu;
int cpu = smp_processor_id();
struct tss_struct *tss = &per_cpu(cpu_tss, cpu);
- fpu_switch_t fpu;
+ fpu_switch_t fpu_switch;

/* never put a printk in __switch_to... printk() calls wake_up*() indirectly */

- fpu = switch_fpu_prepare(&prev_p->thread.fpu, &next_p->thread.fpu, cpu);
+ fpu_switch = switch_fpu_prepare(prev_fpu, next_fpu, cpu);

/*
* Save away %gs. No need to save %fs, as it was saved on the
@@ -318,7 +320,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
if (prev->gs | next->gs)
lazy_load_gs(next->gs);

- switch_fpu_finish(next_p, fpu);
+ switch_fpu_finish(next_fpu, fpu_switch);

this_cpu_write(current_task, next_p);

diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index fefe65efd9d6..4504569c6c4e 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -273,12 +273,14 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
{
struct thread_struct *prev = &prev_p->thread;
struct thread_struct *next = &next_p->thread;
+ struct fpu *prev_fpu = &prev->fpu;
+ struct fpu *next_fpu = &next->fpu;
int cpu = smp_processor_id();
struct tss_struct *tss = &per_cpu(cpu_tss, cpu);
unsigned fsindex, gsindex;
- fpu_switch_t fpu;
+ fpu_switch_t fpu_switch;

- fpu = switch_fpu_prepare(&prev_p->thread.fpu, &next_p->thread.fpu, cpu);
+ fpu_switch = switch_fpu_prepare(prev_fpu, next_fpu, cpu);

/* We must save %fs and %gs before load_TLS() because
* %fs and %gs may be cleared by load_TLS().
@@ -390,7 +392,7 @@ __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_fpu_finish(next_fpu, fpu_switch);

/*
* Switch the PDA and FPU contexts.
--
2.1.0