Files
kernel_arpi/arch/powerpc/kernel/signal.h
Christophe Leroy b6254ced4d powerpc/signal: Don't manage floating point regs when no FPU
There is no point in copying floating point regs when there
is no FPU and MATH_EMULATION is not selected.

Create a new CONFIG_PPC_FPU_REGS bool that is selected by
CONFIG_MATH_EMULATION and CONFIG_PPC_FPU, and use it to
opt out everything related to fp_state in thread_struct.

The asm const used only by fpu.S are opted out with CONFIG_PPC_FPU
as fpu.S build is conditionnal to CONFIG_PPC_FPU.

The following app spends approx 8.1 seconds system time on an 8xx
without the patch, and 7.0 seconds with the patch (13.5% reduction).

On an 832x, it spends approx 2.6 seconds system time without
the patch and 2.1 seconds with the patch (19% reduction).

	void sigusr1(int sig) { }

	int main(int argc, char **argv)
	{
		int i = 100000;

		signal(SIGUSR1, sigusr1);
		for (;i--;)
			raise(SIGUSR1);
		exit(0);
	}

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7569070083e6cd5b279bb5023da601aba3c06f3c.1597770847.git.christophe.leroy@csgroup.eu
2020-12-04 01:01:11 +11:00

99 lines
2.9 KiB
C

/*
* Copyright (c) 2007 Benjamin Herrenschmidt, IBM Corporation
* Extracted from signal_32.c and signal_64.c
*
* This file is subject to the terms and conditions of the GNU General
* Public License. See the file README.legal in the main directory of
* this archive for more details.
*/
#ifndef _POWERPC_ARCH_SIGNAL_H
#define _POWERPC_ARCH_SIGNAL_H
extern void __user *get_sigframe(struct ksignal *ksig, unsigned long sp,
size_t frame_size, int is_32);
extern int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
struct task_struct *tsk);
extern int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
struct task_struct *tsk);
extern unsigned long get_tm_stackpointer(struct task_struct *tsk);
#ifdef CONFIG_VSX
extern unsigned long copy_vsx_to_user(void __user *to,
struct task_struct *task);
extern unsigned long copy_ckvsx_to_user(void __user *to,
struct task_struct *task);
extern unsigned long copy_vsx_from_user(struct task_struct *task,
void __user *from);
extern unsigned long copy_ckvsx_from_user(struct task_struct *task,
void __user *from);
unsigned long copy_fpr_to_user(void __user *to, struct task_struct *task);
unsigned long copy_ckfpr_to_user(void __user *to, struct task_struct *task);
unsigned long copy_fpr_from_user(struct task_struct *task, void __user *from);
unsigned long copy_ckfpr_from_user(struct task_struct *task, void __user *from);
#elif defined(CONFIG_PPC_FPU_REGS)
static inline unsigned long
copy_fpr_to_user(void __user *to, struct task_struct *task)
{
return __copy_to_user(to, task->thread.fp_state.fpr,
ELF_NFPREG * sizeof(double));
}
static inline unsigned long
copy_fpr_from_user(struct task_struct *task, void __user *from)
{
return __copy_from_user(task->thread.fp_state.fpr, from,
ELF_NFPREG * sizeof(double));
}
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
inline unsigned long copy_ckfpr_to_user(void __user *to, struct task_struct *task)
{
return __copy_to_user(to, task->thread.ckfp_state.fpr,
ELF_NFPREG * sizeof(double));
}
static inline unsigned long
copy_ckfpr_from_user(struct task_struct *task, void __user *from)
{
return __copy_from_user(task->thread.ckfp_state.fpr, from,
ELF_NFPREG * sizeof(double));
}
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
#else
static inline unsigned long
copy_fpr_to_user(void __user *to, struct task_struct *task)
{
return 0;
}
static inline unsigned long
copy_fpr_from_user(struct task_struct *task, void __user *from)
{
return 0;
}
#endif
#ifdef CONFIG_PPC64
extern int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
struct task_struct *tsk);
#else /* CONFIG_PPC64 */
extern long sys_rt_sigreturn(void);
extern long sys_sigreturn(void);
static inline int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
struct task_struct *tsk)
{
return -EFAULT;
}
#endif /* !defined(CONFIG_PPC64) */
#endif /* _POWERPC_ARCH_SIGNAL_H */