x86/fpu: Move all the fpu__*() high level methods closer to each other

The fpu__*() methods are closely related, but they are defined
in scattered places within the FPU code.

Concentrate them, and also uninline fpu__save(), fpu__drop()
and fpu__reset() to save about 5K of kernel text on 64-bit kernels:

   text            data    bss     dec        filename
   14113063        2575280 1634304 18322647   vmlinux.before
   14108070        2575280 1634304 18317654   vmlinux.after

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
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 2015-04-29 20:24:14 +02:00
parent 0e75c54f17
commit 6ffc152e46
2 changed files with 48 additions and 43 deletions

View File

@ -46,10 +46,19 @@ extern void fpu__init_system(struct cpuinfo_x86 *c);
extern void fpu__activate_curr(struct fpu *fpu); extern void fpu__activate_curr(struct fpu *fpu);
extern void fpstate_init(struct fpu *fpu); extern void fpstate_init(struct fpu *fpu);
extern void fpu__clear(struct task_struct *tsk);
extern int dump_fpu(struct pt_regs *, struct user_i387_struct *); extern int dump_fpu(struct pt_regs *, struct user_i387_struct *);
/*
* High level FPU state handling functions:
*/
extern void fpu__save(struct fpu *fpu);
extern void fpu__restore(void); extern void fpu__restore(void);
extern void fpu__drop(struct fpu *fpu);
extern int fpu__copy(struct fpu *dst_fpu, struct fpu *src_fpu);
extern void fpu__reset(struct fpu *fpu);
extern void fpu__clear(struct task_struct *tsk);
extern void fpu__init_check_bugs(void); extern void fpu__init_check_bugs(void);
extern void fpu__resume_cpu(void); extern void fpu__resume_cpu(void);
@ -287,8 +296,6 @@ static inline int copy_fpregs_to_fpstate(struct fpu *fpu)
return 0; return 0;
} }
extern void fpu__save(struct fpu *fpu);
static inline int __copy_fpstate_to_fpregs(struct fpu *fpu) static inline int __copy_fpstate_to_fpregs(struct fpu *fpu)
{ {
if (use_xsave()) if (use_xsave())
@ -382,33 +389,6 @@ static inline void fpregs_deactivate(struct fpu *fpu)
__fpregs_deactivate_hw(); __fpregs_deactivate_hw();
} }
/*
* Drops current FPU state: deactivates the fpregs and
* the fpstate. NOTE: it still leaves previous contents
* in the fpregs in the eager-FPU case.
*
* This function can be used in cases where we know that
* a state-restore is coming: either an explicit one,
* or a reschedule.
*/
static inline void fpu__drop(struct fpu *fpu)
{
preempt_disable();
fpu->counter = 0;
if (fpu->fpregs_active) {
/* Ignore delayed exceptions from user space */
asm volatile("1: fwait\n"
"2:\n"
_ASM_EXTABLE(1b, 2b));
fpregs_deactivate(fpu);
}
fpu->fpstate_active = 0;
preempt_enable();
}
static inline void restore_init_xstate(void) static inline void restore_init_xstate(void)
{ {
if (use_xsave()) if (use_xsave())
@ -417,17 +397,6 @@ static inline void restore_init_xstate(void)
fxrstor_checking(&init_xstate_ctx.i387); fxrstor_checking(&init_xstate_ctx.i387);
} }
/*
* Reset the FPU state back to init state.
*/
static inline void fpu__reset(struct fpu *fpu)
{
if (!use_eager_fpu())
fpu__drop(fpu);
else
restore_init_xstate();
}
/* /*
* Definitions for the eXtended Control Register instructions * Definitions for the eXtended Control Register instructions
*/ */
@ -597,8 +566,6 @@ static inline unsigned short get_fpu_mxcsr(struct task_struct *tsk)
} }
} }
extern int fpu__copy(struct fpu *dst_fpu, struct fpu *src_fpu);
static inline unsigned long static inline unsigned long
alloc_mathframe(unsigned long sp, int ia32_frame, unsigned long *buf_fx, alloc_mathframe(unsigned long sp, int ia32_frame, unsigned long *buf_fx,
unsigned long *size) unsigned long *size)

View File

@ -348,6 +348,44 @@ void fpu__restore(void)
} }
EXPORT_SYMBOL_GPL(fpu__restore); EXPORT_SYMBOL_GPL(fpu__restore);
/*
* Drops current FPU state: deactivates the fpregs and
* the fpstate. NOTE: it still leaves previous contents
* in the fpregs in the eager-FPU case.
*
* This function can be used in cases where we know that
* a state-restore is coming: either an explicit one,
* or a reschedule.
*/
void fpu__drop(struct fpu *fpu)
{
preempt_disable();
fpu->counter = 0;
if (fpu->fpregs_active) {
/* Ignore delayed exceptions from user space */
asm volatile("1: fwait\n"
"2:\n"
_ASM_EXTABLE(1b, 2b));
fpregs_deactivate(fpu);
}
fpu->fpstate_active = 0;
preempt_enable();
}
/*
* Reset the FPU state back to init state:
*/
void fpu__reset(struct fpu *fpu)
{
if (!use_eager_fpu())
fpu__drop(fpu);
else
restore_init_xstate();
}
/* /*
* Called by sys_execve() to clear the FPU fpregs, so that FPU state * Called by sys_execve() to clear the FPU fpregs, so that FPU state
* of the previous binary does not leak over into the exec()ed binary: * of the previous binary does not leak over into the exec()ed binary: