x86/fpu: Simplify fpu__unlazy_stopped() error handling

Now that FPU contexts are always allocated, fpu__unlazy_stopped()
cannot fail. Remove its error return and propagate the changes to
the callers.

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: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Ingo Molnar 2015-04-27 06:55:54 +02:00
parent e62bb3d894
commit 2fb29fc7c6
1 changed files with 13 additions and 35 deletions

View File

@ -296,24 +296,18 @@ EXPORT_SYMBOL_GPL(fpstate_init_curr);
* the read-only case, it's not strictly necessary for
* read-only access to the context.
*/
static int fpu__unlazy_stopped(struct fpu *child_fpu)
static void fpu__unlazy_stopped(struct fpu *child_fpu)
{
int ret;
if (WARN_ON_ONCE(child_fpu == &current->thread.fpu))
return -EINVAL;
WARN_ON_ONCE(child_fpu == &current->thread.fpu);
if (child_fpu->fpstate_active) {
child_fpu->last_cpu = -1;
return 0;
} else {
fpstate_init(child_fpu);
/* Safe to do for stopped child tasks: */
child_fpu->fpstate_active = 1;
}
fpstate_init(child_fpu);
/* Safe to do for stopped child tasks: */
child_fpu->fpstate_active = 1;
return 0;
}
/*
@ -389,15 +383,11 @@ int xfpregs_get(struct task_struct *target, const struct user_regset *regset,
void *kbuf, void __user *ubuf)
{
struct fpu *fpu = &target->thread.fpu;
int ret;
if (!cpu_has_fxsr)
return -ENODEV;
ret = fpu__unlazy_stopped(fpu);
if (ret)
return ret;
fpu__unlazy_stopped(fpu);
sanitize_i387_state(target);
return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
@ -414,10 +404,7 @@ int xfpregs_set(struct task_struct *target, const struct user_regset *regset,
if (!cpu_has_fxsr)
return -ENODEV;
ret = fpu__unlazy_stopped(fpu);
if (ret)
return ret;
fpu__unlazy_stopped(fpu);
sanitize_i387_state(target);
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
@ -449,9 +436,7 @@ int xstateregs_get(struct task_struct *target, const struct user_regset *regset,
if (!cpu_has_xsave)
return -ENODEV;
ret = fpu__unlazy_stopped(fpu);
if (ret)
return ret;
fpu__unlazy_stopped(fpu);
xsave = &fpu->state.xsave;
@ -480,9 +465,7 @@ int xstateregs_set(struct task_struct *target, const struct user_regset *regset,
if (!cpu_has_xsave)
return -ENODEV;
ret = fpu__unlazy_stopped(fpu);
if (ret)
return ret;
fpu__unlazy_stopped(fpu);
xsave = &fpu->state.xsave;
@ -643,11 +626,8 @@ int fpregs_get(struct task_struct *target, const struct user_regset *regset,
{
struct fpu *fpu = &target->thread.fpu;
struct user_i387_ia32_struct env;
int ret;
ret = fpu__unlazy_stopped(fpu);
if (ret)
return ret;
fpu__unlazy_stopped(fpu);
if (!static_cpu_has(X86_FEATURE_FPU))
return fpregs_soft_get(target, regset, pos, count, kbuf, ubuf);
@ -677,9 +657,7 @@ int fpregs_set(struct task_struct *target, const struct user_regset *regset,
struct user_i387_ia32_struct env;
int ret;
ret = fpu__unlazy_stopped(fpu);
if (ret)
return ret;
fpu__unlazy_stopped(fpu);
sanitize_i387_state(target);