From 278d91c4609d55202c1e63d5fc5f01466cc7bbab Mon Sep 17 00:00:00 2001 From: Akira Takeuchi Date: Wed, 27 Oct 2010 17:28:52 +0100 Subject: MN10300: Make the FPU operate in non-lazy mode under SMP 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 Signed-off-by: Kiyoshi Owada Signed-off-by: David Howells --- arch/mn10300/Kconfig | 15 ++ arch/mn10300/include/asm/elf.h | 2 - arch/mn10300/include/asm/exceptions.h | 1 - arch/mn10300/include/asm/fpu.h | 157 ++++++++++++------- arch/mn10300/include/asm/processor.h | 1 + arch/mn10300/include/asm/system.h | 16 ++ arch/mn10300/kernel/Makefile | 8 +- arch/mn10300/kernel/asm-offsets.c | 9 ++ arch/mn10300/kernel/fpu-low.S | 265 ++++++++++++++++++++------------ arch/mn10300/kernel/fpu-nofpu-low.S | 39 +++++ arch/mn10300/kernel/fpu-nofpu.c | 30 ++++ arch/mn10300/kernel/fpu.c | 141 +++++++---------- arch/mn10300/kernel/traps.c | 2 - arch/mn10300/proc-mn103e010/proc-init.c | 2 + 14 files changed, 440 insertions(+), 248 deletions(-) create mode 100644 arch/mn10300/kernel/fpu-nofpu-low.S create mode 100644 arch/mn10300/kernel/fpu-nofpu.c (limited to 'arch/mn10300') diff --git a/arch/mn10300/Kconfig b/arch/mn10300/Kconfig index 7bd920b..a1f334c 100644 --- a/arch/mn10300/Kconfig +++ b/arch/mn10300/Kconfig @@ -140,6 +140,21 @@ config FPU default y depends on MN10300_PROC_MN103E010 +config LAZY_SAVE_FPU + bool "Save FPU state lazily" + default y + depends on FPU && !SMP + help + Enable this to be lazy in the saving of the FPU state to the owning + task's thread struct. This is useful if most tasks on the system + don't use the FPU as only those tasks that use it will pass it + between them, and the state needn't be saved for a task that isn't + using it. + + This can't be so easily used on SMP as the process that owns the FPU + state on a CPU may be currently running on another CPU, so for the + moment, it is disabled. + source "arch/mn10300/mm/Kconfig.cache" config MN10300_TLB_USE_PIDR diff --git a/arch/mn10300/include/asm/elf.h b/arch/mn10300/include/asm/elf.h index e5fa97c..a30d220 100644 --- a/arch/mn10300/include/asm/elf.h +++ b/arch/mn10300/include/asm/elf.h @@ -47,8 +47,6 @@ typedef struct { u_int32_t fpcr; } elf_fpregset_t; -extern int dump_fpu(struct pt_regs *, elf_fpregset_t *); - /* * This is used to ensure we don't load something for the wrong architecture */ diff --git a/arch/mn10300/include/asm/exceptions.h b/arch/mn10300/include/asm/exceptions.h index 3f3826a..7d8080b 100644 --- a/arch/mn10300/include/asm/exceptions.h +++ b/arch/mn10300/include/asm/exceptions.h @@ -101,7 +101,6 @@ extern asmlinkage void dtlb_aerror(void); extern asmlinkage void raw_bus_error(void); extern asmlinkage void double_fault(void); extern asmlinkage int system_call(struct pt_regs *); -extern asmlinkage void fpu_exception(struct pt_regs *, enum exception_code); extern asmlinkage void nmi(struct pt_regs *, enum exception_code); extern asmlinkage void uninitialised_exception(struct pt_regs *, enum exception_code); diff --git a/arch/mn10300/include/asm/fpu.h b/arch/mn10300/include/asm/fpu.h index 64a2b83..b7625de 100644 --- a/arch/mn10300/include/asm/fpu.h +++ b/arch/mn10300/include/asm/fpu.h @@ -12,74 +12,125 @@ #ifndef _ASM_FPU_H #define _ASM_FPU_H -#include +#ifndef __ASSEMBLY__ + +#include +#include #include -#include #ifdef __KERNEL__ -/* the task that owns the FPU state */ +extern asmlinkage void fpu_disabled(void); + +#ifdef CONFIG_FPU + +#ifdef CONFIG_LAZY_SAVE_FPU +/* the task that currently owns the FPU state */ extern struct task_struct *fpu_state_owner; +#endif -#define set_using_fpu(tsk) \ -do { \ - (tsk)->thread.fpu_flags |= THREAD_USING_FPU; \ -} while (0) +#if (THREAD_USING_FPU & ~0xff) +#error THREAD_USING_FPU must be smaller than 0x100. +#endif -#define clear_using_fpu(tsk) \ -do { \ - (tsk)->thread.fpu_flags &= ~THREAD_USING_FPU; \ -} while (0) +static inline void set_using_fpu(struct task_struct *tsk) +{ + asm volatile( + "bset %0,(0,%1)" + : + : "i"(THREAD_USING_FPU), "a"(&tsk->thread.fpu_flags) + : "memory", "cc"); +} -#define is_using_fpu(tsk) ((tsk)->thread.fpu_flags & THREAD_USING_FPU) +static inline void clear_using_fpu(struct task_struct *tsk) +{ + asm volatile( + "bclr %0,(0,%1)" + : + : "i"(THREAD_USING_FPU), "a"(&tsk->thread.fpu_flags) + : "memory", "cc"); +} -#define unlazy_fpu(tsk) \ -do { \ - preempt_disable(); \ - if (fpu_state_owner == (tsk)) \ - fpu_save(&tsk->thread.fpu_state); \ - preempt_enable(); \ -} while (0) - -#define exit_fpu() \ -do { \ - struct task_struct *__tsk = current; \ - preempt_disable(); \ - if (fpu_state_owner == __tsk) \ - fpu_state_owner = NULL; \ - preempt_enable(); \ -} while (0) - -#define flush_fpu() \ -do { \ - struct task_struct *__tsk = current; \ - preempt_disable(); \ - if (fpu_state_owner == __tsk) { \ - fpu_state_owner = NULL; \ - __tsk->thread.uregs->epsw &= ~EPSW_FE; \ - } \ - preempt_enable(); \ - clear_using_fpu(__tsk); \ -} while (0) +#define is_using_fpu(tsk) ((tsk)->thread.fpu_flags & THREAD_USING_FPU) -extern asmlinkage void fpu_init_state(void); extern asmlinkage void fpu_kill_state(struct task_struct *); -extern asmlinkage void fpu_disabled(struct pt_regs *, enum exception_code); extern asmlinkage void fpu_exception(struct pt_regs *, enum exception_code); - -#ifdef CONFIG_FPU +extern asmlinkage void fpu_invalid_op(struct pt_regs *, enum exception_code); +extern asmlinkage void fpu_init_state(void); extern asmlinkage void fpu_save(struct fpu_state_struct *); -extern asmlinkage void fpu_restore(struct fpu_state_struct *); -#else -#define fpu_save(a) -#define fpu_restore(a) -#endif /* CONFIG_FPU */ - -/* - * signal frame handlers - */ extern int fpu_setup_sigcontext(struct fpucontext *buf); extern int fpu_restore_sigcontext(struct fpucontext *buf); +static inline void unlazy_fpu(struct task_struct *tsk) +{ + preempt_disable(); +#ifndef CONFIG_LAZY_SAVE_FPU + if (tsk->thread.fpu_flags & THREAD_HAS_FPU) { + fpu_save(&tsk->thread.fpu_state); + tsk->thread.fpu_flags &= ~THREAD_HAS_FPU; + tsk->thread.uregs->epsw &= ~EPSW_FE; + } +#else + if (fpu_state_owner == tsk) + fpu_save(&tsk->thread.fpu_state); +#endif + preempt_enable(); +} + +static inline void exit_fpu(void) +{ +#ifdef CONFIG_LAZY_SAVE_FPU + struct task_struct *tsk = current; + + preempt_disable(); + if (fpu_state_owner == tsk) + fpu_state_owner = NULL; + preempt_enable(); +#endif +} + +static inline void flush_fpu(void) +{ + struct task_struct *tsk = current; + + preempt_disable(); +#ifndef CONFIG_LAZY_SAVE_FPU + if (tsk->thread.fpu_flags & THREAD_HAS_FPU) { + tsk->thread.fpu_flags &= ~THREAD_HAS_FPU; + tsk->thread.uregs->epsw &= ~EPSW_FE; + } +#else + if (fpu_state_owner == tsk) { + fpu_state_owner = NULL; + tsk->thread.uregs->epsw &= ~EPSW_FE; + } +#endif + preempt_enable(); + clear_using_fpu(tsk); +} + +#else /* CONFIG_FPU */ + +extern asmlinkage +void unexpected_fpu_exception(struct pt_regs *, enum exception_code); +#define fpu_invalid_op unexpected_fpu_exception +#define fpu_exception unexpected_fpu_exception + +struct task_struct; +struct fpu_state_struct; +static inline bool is_using_fpu(struct task_struct *tsk) { return false; } +static inline void set_using_fpu(struct task_struct *tsk) {} +static inline void clear_using_fpu(struct task_struct *tsk) {} +static inline void fpu_init_state(void) {} +static inline void fpu_save(struct fpu_state_struct *s) {} +static inline void fpu_kill_state(struct task_struct *tsk) {} +static inline void unlazy_fpu(struct task_struct *tsk) {} +static inline void exit_fpu(void) {} +static inline void flush_fpu(void) {} +static inline int fpu_setup_sigcontext(struct fpucontext *buf) { return 0; } +static inline int fpu_restore_sigcontext(struct fpucontext *buf) { return 0; } +#endif /* CONFIG_FPU */ + #endif /* __KERNEL__ */ +#endif /* !__ASSEMBLY__ */ #endif /* _ASM_FPU_H */ diff --git a/arch/mn10300/include/asm/processor.h b/arch/mn10300/include/asm/processor.h index fd96c18..0032fc7 100644 --- a/arch/mn10300/include/asm/processor.h +++ b/arch/mn10300/include/asm/processor.h @@ -95,6 +95,7 @@ struct thread_struct { struct pt_regs *__frame; unsigned long fpu_flags; #define THREAD_USING_FPU 0x00000001 /* T if this task is using the FPU */ +#define THREAD_HAS_FPU 0x00000002 /* T if this task owns the FPU right now */ struct fpu_state_struct fpu_state; }; diff --git a/arch/mn10300/include/asm/system.h b/arch/mn10300/include/asm/system.h index 9f7c7e1..3c272a1 100644 --- a/arch/mn10300/include/asm/system.h +++ b/arch/mn10300/include/asm/system.h @@ -19,6 +19,21 @@ #include #include +#if !defined(CONFIG_LAZY_SAVE_FPU) +struct fpu_state_struct; +extern asmlinkage void fpu_save(struct fpu_state_struct *); +#define switch_fpu(prev, next) \ + do { \ + if ((prev)->thread.fpu_flags & THREAD_HAS_FPU) { \ + (prev)->thread.fpu_flags &= ~THREAD_HAS_FPU; \ + (prev)->thread.uregs->epsw &= ~EPSW_FE; \ + fpu_save(&(prev)->thread.fpu_state); \ + } \ + } while (0) +#else +#define switch_fpu(prev, next) do {} while (0) +#endif + struct task_struct; struct thread_struct; @@ -30,6 +45,7 @@ struct task_struct *__switch_to(struct thread_struct *prev, /* context switching is now performed out-of-line in switch_to.S */ #define switch_to(prev, next, last) \ do { \ + switch_fpu(prev, next); \ current->thread.wchan = (u_long) __builtin_return_address(0); \ (last) = __switch_to(&(prev)->thread, &(next)->thread, (prev)); \ mb(); \ diff --git a/arch/mn10300/kernel/Makefile b/arch/mn10300/kernel/Makefile index c4289e3..9902235 100644 --- a/arch/mn10300/kernel/Makefile +++ b/arch/mn10300/kernel/Makefile @@ -3,13 +3,15 @@ # extra-y := head.o init_task.o vmlinux.lds -obj-y := process.o signal.o entry.o fpu.o traps.o irq.o \ +fpu-obj-y := fpu-nofpu.o fpu-nofpu-low.o +fpu-obj-$(CONFIG_FPU) := fpu.o fpu-low.o + +obj-y := process.o signal.o entry.o traps.o irq.o \ ptrace.o setup.o time.o sys_mn10300.o io.o kthread.o \ - switch_to.o mn10300_ksyms.o kernel_execve.o + switch_to.o mn10300_ksyms.o kernel_execve.o $(fpu-obj-y) obj-$(CONFIG_MN10300_WD_TIMER) += mn10300-watchdog.o mn10300-watchdog-low.o -obj-$(CONFIG_FPU) += fpu-low.o obj-$(CONFIG_MN10300_TTYSM) += mn10300-serial.o mn10300-serial-low.o \ mn10300-debug.o diff --git a/arch/mn10300/kernel/asm-offsets.c b/arch/mn10300/kernel/asm-offsets.c index 02dc7e4..78e290e 100644 --- a/arch/mn10300/kernel/asm-offsets.c +++ b/arch/mn10300/kernel/asm-offsets.c @@ -67,6 +67,15 @@ void foo(void) OFFSET(THREAD_A3, thread_struct, a3); OFFSET(THREAD_USP, thread_struct, usp); OFFSET(THREAD_FRAME, thread_struct, __frame); +#ifdef CONFIG_FPU + OFFSET(THREAD_FPU_FLAGS, thread_struct, fpu_flags); + OFFSET(THREAD_FPU_STATE, thread_struct, fpu_state); + DEFINE(__THREAD_USING_FPU, THREAD_USING_FPU); + DEFINE(__THREAD_HAS_FPU, THREAD_HAS_FPU); +#endif /* CONFIG_FPU */ + BLANK(); + + OFFSET(TASK_THREAD, task_struct, thread); BLANK(); DEFINE(CLONE_VM_asm, CLONE_VM); diff --git a/arch/mn10300/kernel/fpu-low.S b/arch/mn10300/kernel/fpu-low.S index 96cfd47..78df25c 100644 --- a/arch/mn10300/kernel/fpu-low.S +++ b/arch/mn10300/kernel/fpu-low.S @@ -8,25 +8,14 @@ * as published by the Free Software Foundation; either version * 2 of the Licence, or (at your option) any later version. */ +#include #include +#include +#include +#include +#include -############################################################################### -# -# void fpu_init_state(void) -# - initialise the FPU -# -############################################################################### - .globl fpu_init_state - .type fpu_init_state,@function -fpu_init_state: - mov epsw,d0 - or EPSW_FE,epsw - -#ifdef CONFIG_MN10300_PROC_MN103E010 - nop - nop - nop -#endif +.macro FPU_INIT_STATE_ALL fmov 0,fs0 fmov fs0,fs1 fmov fs0,fs2 @@ -60,7 +49,100 @@ fpu_init_state: fmov fs0,fs30 fmov fs0,fs31 fmov FPCR_INIT,fpcr +.endm + +.macro FPU_SAVE_ALL areg,dreg + fmov fs0,(\areg+) + fmov fs1,(\areg+) + fmov fs2,(\areg+) + fmov fs3,(\areg+) + fmov fs4,(\areg+) + fmov fs5,(\areg+) + fmov fs6,(\areg+) + fmov fs7,(\areg+) + fmov fs8,(\areg+) + fmov fs9,(\areg+) + fmov fs10,(\areg+) + fmov fs11,(\areg+) + fmov fs12,(\areg+) + fmov fs13,(\areg+) + fmov fs14,(\areg+) + fmov fs15,(\areg+) + fmov fs16,(\areg+) + fmov fs17,(\areg+) + fmov fs18,(\areg+) + fmov fs19,(\areg+) + fmov fs20,(\areg+) + fmov fs21,(\areg+) + fmov fs22,(\areg+) + fmov fs23,(\areg+) + fmov fs24,(\areg+) + fmov fs25,(\areg+) + fmov fs26,(\areg+) + fmov fs27,(\areg+) + fmov fs28,(\areg+) + fmov fs29,(\areg+) + fmov fs30,(\areg+) + fmov fs31,(\areg+) + fmov fpcr,\dreg + mov \dreg,(\areg) +.endm + +.macro FPU_RESTORE_ALL areg,dreg + fmov (\areg+),fs0 + fmov (\areg+),fs1 + fmov (\areg+),fs2 + fmov (\areg+),fs3 + fmov (\areg+),fs4 + fmov (\areg+),fs5 + fmov (\areg+),fs6 + fmov (\areg+),fs7 + fmov (\areg+),fs8 + fmov (\areg+),fs9 + fmov (\areg+),fs10 + fmov (\areg+),fs11 + fmov (\areg+),fs12 + fmov (\areg+),fs13 + fmov (\areg+),fs14 + fmov (\areg+),fs15 + fmov (\areg+),fs16 + fmov (\areg+),fs17 + fmov (\areg+),fs18 + fmov (\areg+),fs19 + fmov (\areg+),fs20 + fmov (\areg+),fs21 + fmov (\areg+),fs22 + fmov (\areg+),fs23 + fmov (\areg+),fs24 + fmov (\areg+),fs25 + fmov (\areg+),fs26 + fmov (\areg+),fs27 + fmov (\areg+),fs28 + fmov (\areg+),fs29 + fmov (\areg+),fs30 + fmov (\areg+),fs31 + mov (\areg),\dreg + fmov \dreg,fpcr +.endm +############################################################################### +# +# void fpu_init_state(void) +# - initialise the FPU +# +############################################################################### + .globl fpu_init_state + .type fpu_init_state,@function +fpu_init_state: + mov epsw,d0 + or EPSW_FE,epsw + +#ifdef CONFIG_MN10300_PROC_MN103E010 + nop + nop + nop +#endif + FPU_INIT_STATE_ALL #ifdef CONFIG_MN10300_PROC_MN103E010 nop nop @@ -89,40 +171,7 @@ fpu_save: nop #endif mov d0,a0 - fmov fs0,(a0+) - fmov fs1,(a0+) - fmov fs2,(a0+) - fmov fs3,(a0+) - fmov fs4,(a0+) - fmov fs5,(a0+) - fmov fs6,(a0+) - fmov fs7,(a0+) - fmov fs8,(a0+) - fmov fs9,(a0+) - fmov fs10,(a0+) - fmov fs11,(a0+) - fmov fs12,(a0+) - fmov fs13,(a0+) - fmov fs14,(a0+) - fmov fs15,(a0+) - fmov fs16,(a0+) - fmov fs17,(a0+) - fmov fs18,(a0+) - fmov fs19,(a0+) - fmov fs20,(a0+) - fmov fs21,(a0+) - fmov fs22,(a0+) - fmov fs23,(a0+) - fmov fs24,(a0+) - fmov fs25,(a0+) - fmov fs26,(a0+) - fmov fs27,(a0+) - fmov fs28,(a0+) - fmov fs29,(a0+) - fmov fs30,(a0+) - fmov fs31,(a0+) - fmov fpcr,d0 - mov d0,(a0) + FPU_SAVE_ALL a0,d0 #ifdef CONFIG_MN10300_PROC_MN103E010 nop nop @@ -135,63 +184,75 @@ fpu_save: ############################################################################### # -# void fpu_restore(struct fpu_state_struct *) -# - restore the fpu state -# - note that an FPU Operational exception might occur during this process +# void fpu_disabled(void) +# - handle an exception due to the FPU being disabled +# when CONFIG_FPU is enabled # ############################################################################### - .globl fpu_restore - .type fpu_restore,@function -fpu_restore: - mov epsw,d1 - or EPSW_FE,epsw /* enable the FPU so we can access it */ - -#ifdef CONFIG_MN10300_PROC_MN103E010 + .type fpu_disabled,@function + .globl fpu_disabled +fpu_disabled: + or EPSW_nAR|EPSW_FE,epsw nop nop -#endif - mov d0,a0 - fmov (a0+),fs0 - fmov (a0+),fs1 - fmov (a0+),fs2 - fmov (a0+),fs3 - fmov (a0+),fs4 - fmov (a0+),fs5 - fmov (a0+),fs6 - fmov (a0+),fs7 - fmov (a0+),fs8 - fmov (a0+),fs9 - fmov (a0+),fs10 - fmov (a0+),fs11 - fmov (a0+),fs12 - fmov (a0+),fs13 - fmov (a0+),fs14 - fmov (a0+),fs15 - fmov (a0+),fs16 - fmov (a0+),fs17 - fmov (a0+),fs18 - fmov (a0+),fs19 - fmov (a0+),fs20 - fmov (a0+),fs21 - fmov (a0+),fs22 - fmov (a0+),fs23 - fmov (a0+),fs24 - fmov (a0+),fs25 - fmov (a0+),fs26 - fmov (a0+),fs27 - fmov (a0+),fs28 - fmov (a0+),fs29 - fmov (a0+),fs30 - fmov (a0+),fs31 - mov (a0),d0 - fmov d0,fpcr -#ifdef CONFIG_MN10300_PROC_MN103E010 nop + + mov sp,a1 + mov (a1),d1 /* get epsw of user context */ + and ~(THREAD_SIZE-1),a1 /* a1: (thread_info *ti) */ + mov (TI_task,a1),a2 /* a2: (task_struct *tsk) */ + btst EPSW_nSL,d1 + beq fpu_used_in_kernel + + or EPSW_FE,d1 + mov d1,(sp) + mov (TASK_THREAD+THREAD_FPU_FLAGS,a2),d1 +#ifndef CONFIG_LAZY_SAVE_FPU + or __THREAD_HAS_FPU,d1 + mov d1,(TASK_THREAD+THREAD_FPU_FLAGS,a2) +#else /* !CONFIG_LAZY_SAVE_FPU */ + mov (fpu_state_owner),a0 + cmp 0,a0 + beq fpu_regs_save_end + + mov (TASK_THREAD+THREAD_UREGS,a0),a1 + add TASK_THREAD+THREAD_FPU_STATE,a0 + FPU_SAVE_ALL a0,d0 + + mov (REG_EPSW,a1),d0 + and ~EPSW_FE,d0 + mov d0,(REG_EPSW,a1) + +fpu_regs_save_end: + mov a2,(fpu_state_owner) +#endif /* !CONFIG_LAZY_SAVE_FPU */ + + btst __THREAD_USING_FPU,d1 + beq fpu_regs_init + add TASK_THREAD+THREAD_FPU_STATE,a2 + FPU_RESTORE_ALL a2,d0 + rti + +fpu_regs_init: + FPU_INIT_STATE_ALL + add TASK_THREAD+THREAD_FPU_FLAGS,a2 + bset __THREAD_USING_FPU,(0,a2) + rti + +fpu_used_in_kernel: + and ~(EPSW_nAR|EPSW_FE),epsw nop nop -#endif - mov d1,epsw - ret [],0 + add -4,sp + SAVE_ALL + mov -1,d0 + mov d0,(REG_ORIG_D0,fp) + + and ~EPSW_NMID,epsw + + mov fp,d0 + call fpu_disabled_in_kernel[],0 + jmp ret_from_exception - .size fpu_restore,.-fpu_restore + .size fpu_disabled,.-fpu_disabled diff --git a/arch/mn10300/kernel/fpu-nofpu-low.S b/arch/mn10300/kernel/fpu-nofpu-low.S new file mode 100644 index 0000000..7ea087a --- /dev/null +++ b/arch/mn10300/kernel/fpu-nofpu-low.S @@ -0,0 +1,39 @@ +/* MN10300 Low level FPU management operations + * + * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ +#include +#include +#include +#include +#include +#include + +############################################################################### +# +# void fpu_disabled(void) +# - handle an exception due to the FPU being disabled +# when CONFIG_FPU is disabled +# +############################################################################### + .type fpu_disabled,@function + .globl fpu_disabled +fpu_disabled: + add -4,sp + SAVE_ALL + mov -1,d0 + mov d0,(REG_ORIG_D0,fp) + + and ~EPSW_NMID,epsw + + mov fp,d0 + call unexpected_fpu_exception[],0 + jmp ret_from_exception + + .size fpu_disabled,.-fpu_disabled diff --git a/arch/mn10300/kernel/fpu-nofpu.c b/arch/mn10300/kernel/fpu-nofpu.c new file mode 100644 index 0000000..31c765b --- /dev/null +++ b/arch/mn10300/kernel/fpu-nofpu.c @@ -0,0 +1,30 @@ +/* MN10300 FPU management + * + * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ +#include + +/* + * handle an FPU operational exception + * - there's a possibility that if the FPU is asynchronous, the signal might + * be meant for a process other than the current one + */ +asmlinkage +void unexpected_fpu_exception(struct pt_regs *regs, enum exception_code code) +{ + panic("An FPU exception was received, but there's no FPU enabled."); +} + +/* + * fill in the FPU structure for a core dump + */ +int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpreg) +{ + return 0; /* not valid */ +} diff --git a/arch/mn10300/kernel/fpu.c b/arch/mn10300/kernel/fpu.c index e705f25..5f9c3fa 100644 --- a/arch/mn10300/kernel/fpu.c +++ b/arch/mn10300/kernel/fpu.c @@ -12,56 +12,19 @@ #include #include #include +#include +#ifdef CONFIG_LAZY_SAVE_FPU struct task_struct *fpu_state_owner; +#endif /* - * handle an exception due to the FPU being disabled + * error functions in FPU disabled exception */ -asmlinkage void fpu_disabled(struct pt_regs *regs, enum exception_code code) +asmlinkage void fpu_disabled_in_kernel(struct pt_regs *regs) { - struct task_struct *tsk = current; - - if (!user_mode(regs)) - die_if_no_fixup("An FPU Disabled exception happened in" - " kernel space\n", - regs, code); - -#ifdef CONFIG_FPU - preempt_disable(); - - /* transfer the last process's FPU state to memory */ - if (fpu_state_owner) { - fpu_save(&fpu_state_owner->thread.fpu_state); - fpu_state_owner->thread.uregs->epsw &= ~EPSW_FE; - } - - /* the current process now owns the FPU state */ - fpu_state_owner = tsk; - regs->epsw |= EPSW_FE; - - /* load the FPU with the current process's FPU state or invent a new - * clean one if the process doesn't have one */ - if (is_using_fpu(tsk)) { - fpu_restore(&tsk->thread.fpu_state); - } else { - fpu_init_state(); - set_using_fpu(tsk); - } - - preempt_enable(); -#else - { - siginfo_t info; - - info.si_signo = SIGFPE; - info.si_errno = 0; - info.si_addr = (void *) tsk->thread.uregs->pc; - info.si_code = FPE_FLTINV; - - force_sig_info(SIGFPE, &info, tsk); - } -#endif /* CONFIG_FPU */ + die_if_no_fixup("An FPU Disabled exception happened in kernel space\n", + regs, EXCEP_FPU_DISABLED); } /* @@ -71,15 +34,16 @@ asmlinkage void fpu_disabled(struct pt_regs *regs, enum exception_code code) */ asmlinkage void fpu_exception(struct pt_regs *regs, enum exception_code code) { - struct task_struct *tsk = fpu_state_owner; + struct task_struct *tsk = current; siginfo_t info; + u32 fpcr; if (!user_mode(regs)) die_if_no_fixup("An FPU Operation exception happened in" " kernel space\n", regs, code); - if (!tsk) + if (!is_using_fpu(tsk)) die_if_no_fixup("An FPU Operation exception happened," " but the FPU is not in use", regs, code); @@ -89,48 +53,45 @@ asmlinkage void fpu_exception(struct pt_regs *regs, enum exception_code code) info.si_addr = (void *) tsk->thread.uregs->pc; info.si_code = FPE_FLTINV; -#ifdef CONFIG_FPU - { - u32 fpcr; + unlazy_fpu(tsk); - /* get FPCR (we need to enable the FPU whilst we do this) */ - asm volatile(" or %1,epsw \n" -#ifdef CONFIG_MN10300_PROC_MN103E010 - " nop \n" - " nop \n" - " nop \n" -#endif - " fmov fpcr,%0 \n" -#ifdef CONFIG_MN10300_PROC_MN103E010 - " nop \n" - " nop \n" - " nop \n" -#endif - " and %2,epsw \n" - : "=&d"(fpcr) - : "i"(EPSW_FE), "i"(~EPSW_FE) - ); - - if (fpcr & FPCR_EC_Z) - info.si_code = FPE_FLTDIV; - else if (fpcr & FPCR_EC_O) - info.si_code = FPE_FLTOVF; - else if (fpcr & FPCR_EC_U) - info.si_code = FPE_FLTUND; - else if (fpcr & FPCR_EC_I) - info.si_code = FPE_FLTRES; - } -#endif + fpcr = tsk->thread.fpu_state.fpcr; + + if (fpcr & FPCR_EC_Z) + info.si_code = FPE_FLTDIV; + else if (fpcr & FPCR_EC_O) + info.si_code = FPE_FLTOVF; + else if (fpcr & FPCR_EC_U) + info.si_code = FPE_FLTUND; + else if (fpcr & FPCR_EC_I) + info.si_code = FPE_FLTRES; force_sig_info(SIGFPE, &info, tsk); } /* + * handle an FPU invalid_op exception + * - Derived from DO_EINFO() macro in arch/mn10300/kernel/traps.c + */ +asmlinkage void fpu_invalid_op(struct pt_regs *regs, enum exception_code code) +{ + siginfo_t info; + + if (!user_mode(regs)) + die_if_no_fixup("FPU invalid opcode", regs, code); + + info.si_signo = SIGILL; + info.si_errno = 0; + info.si_code = ILL_COPROC; + info.si_addr = (void *) regs->pc; + force_sig_info(info.si_signo, &info, current); +} + +/* * save the FPU state to a signal context */ int fpu_setup_sigcontext(struct fpucontext *fpucontext) { -#ifdef CONFIG_FPU struct task_struct *tsk = current; if (!is_using_fpu(tsk)) @@ -142,11 +103,19 @@ int fpu_setup_sigcontext(struct fpucontext *fpucontext) */ preempt_disable(); +#ifndef CONFIG_LAZY_SAVE_FPU + if (tsk->thread.fpu_flags & THREAD_HAS_FPU) { + fpu_save(&tsk->thread.fpu_state); + tsk->thread.uregs->epsw &= ~EPSW_FE; + tsk->thread.fpu_flags &= ~THREAD_HAS_FPU; + } +#else /* !CONFIG_LAZY_SAVE_FPU */ if (fpu_state_owner == tsk) { fpu_save(&tsk->thread.fpu_state); fpu_state_owner->thread.uregs->epsw &= ~EPSW_FE; fpu_state_owner = NULL; } +#endif /* !CONFIG_LAZY_SAVE_FPU */ preempt_enable(); @@ -161,9 +130,6 @@ int fpu_setup_sigcontext(struct fpucontext *fpucontext) return -1; return 1; -#else - return 0; -#endif } /* @@ -171,17 +137,23 @@ int fpu_setup_sigcontext(struct fpucontext *fpucontext) */ void fpu_kill_state(struct task_struct *tsk) { -#ifdef CONFIG_FPU /* disown anything left in the FPU */ preempt_disable(); +#ifndef CONFIG_LAZY_SAVE_FPU + if (tsk->thread.fpu_flags & THREAD_HAS_FPU) { + tsk->thread.uregs->epsw &= ~EPSW_FE; + tsk->thread.fpu_flags &= ~THREAD_HAS_FPU; + } +#else /* !CONFIG_LAZY_SAVE_FPU */ if (fpu_state_owner == tsk) { fpu_state_owner->thread.uregs->epsw &= ~EPSW_FE; fpu_state_owner = NULL; } +#endif /* !CONFIG_LAZY_SAVE_FPU */ preempt_enable(); -#endif + /* we no longer have a valid current FPU state */ clear_using_fpu(tsk); } @@ -195,8 +167,7 @@ int fpu_restore_sigcontext(struct fpucontext *fpucontext) int ret; /* load up the old FPU state */ - ret = copy_from_user(&tsk->thread.fpu_state, - fpucontext, + ret = copy_from_user(&tsk->thread.fpu_state, fpucontext, min(sizeof(struct fpu_state_struct), sizeof(struct fpucontext))); if (!ret) diff --git a/arch/mn10300/kernel/traps.c b/arch/mn10300/kernel/traps.c index c7257a1..716a221 100644 --- a/arch/mn10300/kernel/traps.c +++ b/arch/mn10300/kernel/traps.c @@ -101,7 +101,6 @@ DO_EINFO(SIGILL, {}, "invalid opcode", invalid_op, ILL_ILLOPC); DO_EINFO(SIGILL, {}, "invalid ex opcode", invalid_exop, ILL_ILLOPC); DO_EINFO(SIGBUS, {}, "invalid address", mem_error, BUS_ADRERR); DO_EINFO(SIGBUS, {}, "bus error", bus_error, BUS_ADRERR); -DO_EINFO(SIGILL, {}, "FPU invalid opcode", fpu_invalid_op, ILL_COPROC); DO_ERROR(SIGTRAP, #ifndef CONFIG_MN10300_USING_JTAG @@ -561,7 +560,6 @@ void __init trap_init(void) set_excp_vector(EXCEP_PRIVINSACC, insn_acc_error); set_excp_vector(EXCEP_PRIVDATACC, data_acc_error); set_excp_vector(EXCEP_DATINSACC, insn_acc_error); - set_excp_vector(EXCEP_FPU_DISABLED, fpu_disabled); set_excp_vector(EXCEP_FPU_UNIMPINS, fpu_invalid_op); set_excp_vector(EXCEP_FPU_OPERATION, fpu_exception); diff --git a/arch/mn10300/proc-mn103e010/proc-init.c b/arch/mn10300/proc-mn103e010/proc-init.c index 9a482ef..0cee787 100644 --- a/arch/mn10300/proc-mn103e010/proc-init.c +++ b/arch/mn10300/proc-mn103e010/proc-init.c @@ -9,6 +9,7 @@ * 2 of the Licence, or (at your option) any later version. */ #include +#include #include /* @@ -28,6 +29,7 @@ asmlinkage void __init processor_init(void) __set_intr_stub(EXCEP_DAERROR, dtlb_aerror); __set_intr_stub(EXCEP_BUSERROR, raw_bus_error); __set_intr_stub(EXCEP_DOUBLE_FAULT, double_fault); + __set_intr_stub(EXCEP_FPU_DISABLED, fpu_disabled); __set_intr_stub(EXCEP_SYSCALL0, system_call); __set_intr_stub(EXCEP_NMI, nmi_handler); -- cgit v1.1