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278d91c460
Make the FPU operate in non-lazy mode under SMP so that when the process that is currently using the FPU migrates to a different CPU, we don't have to ping its previous CPU to flush the FPU context. Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com> Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com> Signed-off-by: David Howells <dhowells@redhat.com>
137 lines
3.7 KiB
C
137 lines
3.7 KiB
C
/* MN10300 FPU definitions
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*
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* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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* Derived from include/asm-i386/i387.h: Copyright (C) 1994 Linus Torvalds
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public Licence
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* as published by the Free Software Foundation; either version
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* 2 of the Licence, or (at your option) any later version.
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*/
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#ifndef _ASM_FPU_H
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#define _ASM_FPU_H
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#ifndef __ASSEMBLY__
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#include <linux/sched.h>
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#include <asm/exceptions.h>
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#include <asm/sigcontext.h>
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#ifdef __KERNEL__
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extern asmlinkage void fpu_disabled(void);
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#ifdef CONFIG_FPU
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#ifdef CONFIG_LAZY_SAVE_FPU
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/* the task that currently owns the FPU state */
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extern struct task_struct *fpu_state_owner;
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#endif
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#if (THREAD_USING_FPU & ~0xff)
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#error THREAD_USING_FPU must be smaller than 0x100.
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#endif
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static inline void set_using_fpu(struct task_struct *tsk)
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{
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asm volatile(
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"bset %0,(0,%1)"
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:
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: "i"(THREAD_USING_FPU), "a"(&tsk->thread.fpu_flags)
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: "memory", "cc");
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}
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static inline void clear_using_fpu(struct task_struct *tsk)
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{
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asm volatile(
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"bclr %0,(0,%1)"
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:
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: "i"(THREAD_USING_FPU), "a"(&tsk->thread.fpu_flags)
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: "memory", "cc");
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}
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#define is_using_fpu(tsk) ((tsk)->thread.fpu_flags & THREAD_USING_FPU)
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extern asmlinkage void fpu_kill_state(struct task_struct *);
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extern asmlinkage void fpu_exception(struct pt_regs *, enum exception_code);
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extern asmlinkage void fpu_invalid_op(struct pt_regs *, enum exception_code);
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extern asmlinkage void fpu_init_state(void);
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extern asmlinkage void fpu_save(struct fpu_state_struct *);
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extern int fpu_setup_sigcontext(struct fpucontext *buf);
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extern int fpu_restore_sigcontext(struct fpucontext *buf);
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static inline void unlazy_fpu(struct task_struct *tsk)
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{
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preempt_disable();
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#ifndef CONFIG_LAZY_SAVE_FPU
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if (tsk->thread.fpu_flags & THREAD_HAS_FPU) {
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fpu_save(&tsk->thread.fpu_state);
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tsk->thread.fpu_flags &= ~THREAD_HAS_FPU;
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tsk->thread.uregs->epsw &= ~EPSW_FE;
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}
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#else
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if (fpu_state_owner == tsk)
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fpu_save(&tsk->thread.fpu_state);
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#endif
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preempt_enable();
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}
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static inline void exit_fpu(void)
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{
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#ifdef CONFIG_LAZY_SAVE_FPU
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struct task_struct *tsk = current;
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preempt_disable();
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if (fpu_state_owner == tsk)
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fpu_state_owner = NULL;
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preempt_enable();
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#endif
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}
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static inline void flush_fpu(void)
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{
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struct task_struct *tsk = current;
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preempt_disable();
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#ifndef CONFIG_LAZY_SAVE_FPU
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if (tsk->thread.fpu_flags & THREAD_HAS_FPU) {
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tsk->thread.fpu_flags &= ~THREAD_HAS_FPU;
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tsk->thread.uregs->epsw &= ~EPSW_FE;
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}
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#else
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if (fpu_state_owner == tsk) {
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fpu_state_owner = NULL;
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tsk->thread.uregs->epsw &= ~EPSW_FE;
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}
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#endif
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preempt_enable();
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clear_using_fpu(tsk);
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}
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#else /* CONFIG_FPU */
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extern asmlinkage
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void unexpected_fpu_exception(struct pt_regs *, enum exception_code);
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#define fpu_invalid_op unexpected_fpu_exception
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#define fpu_exception unexpected_fpu_exception
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struct task_struct;
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struct fpu_state_struct;
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static inline bool is_using_fpu(struct task_struct *tsk) { return false; }
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static inline void set_using_fpu(struct task_struct *tsk) {}
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static inline void clear_using_fpu(struct task_struct *tsk) {}
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static inline void fpu_init_state(void) {}
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static inline void fpu_save(struct fpu_state_struct *s) {}
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static inline void fpu_kill_state(struct task_struct *tsk) {}
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static inline void unlazy_fpu(struct task_struct *tsk) {}
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static inline void exit_fpu(void) {}
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static inline void flush_fpu(void) {}
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static inline int fpu_setup_sigcontext(struct fpucontext *buf) { return 0; }
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static inline int fpu_restore_sigcontext(struct fpucontext *buf) { return 0; }
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#endif /* CONFIG_FPU */
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#endif /* __KERNEL__ */
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#endif /* !__ASSEMBLY__ */
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#endif /* _ASM_FPU_H */
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