From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/arch/x86/include/asm/fpu-internal.h | 626 +++++++++++++++++++++++++++++ 1 file changed, 626 insertions(+) create mode 100644 kernel/arch/x86/include/asm/fpu-internal.h (limited to 'kernel/arch/x86/include/asm/fpu-internal.h') diff --git a/kernel/arch/x86/include/asm/fpu-internal.h b/kernel/arch/x86/include/asm/fpu-internal.h new file mode 100644 index 000000000..da5e96756 --- /dev/null +++ b/kernel/arch/x86/include/asm/fpu-internal.h @@ -0,0 +1,626 @@ +/* + * Copyright (C) 1994 Linus Torvalds + * + * Pentium III FXSR, SSE support + * General FPU state handling cleanups + * Gareth Hughes , May 2000 + * x86-64 work by Andi Kleen 2002 + */ + +#ifndef _FPU_INTERNAL_H +#define _FPU_INTERNAL_H + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#ifdef CONFIG_X86_64 +# include +# include +struct ksignal; +int ia32_setup_rt_frame(int sig, struct ksignal *ksig, + compat_sigset_t *set, struct pt_regs *regs); +int ia32_setup_frame(int sig, struct ksignal *ksig, + compat_sigset_t *set, struct pt_regs *regs); +#else +# define user_i387_ia32_struct user_i387_struct +# define user32_fxsr_struct user_fxsr_struct +# define ia32_setup_frame __setup_frame +# define ia32_setup_rt_frame __setup_rt_frame +#endif + +extern unsigned int mxcsr_feature_mask; +extern void fpu_init(void); +extern void eager_fpu_init(void); + +DECLARE_PER_CPU(struct task_struct *, fpu_owner_task); + +extern void convert_from_fxsr(struct user_i387_ia32_struct *env, + struct task_struct *tsk); +extern void convert_to_fxsr(struct task_struct *tsk, + const struct user_i387_ia32_struct *env); + +extern user_regset_active_fn fpregs_active, xfpregs_active; +extern user_regset_get_fn fpregs_get, xfpregs_get, fpregs_soft_get, + xstateregs_get; +extern user_regset_set_fn fpregs_set, xfpregs_set, fpregs_soft_set, + xstateregs_set; + +/* + * xstateregs_active == fpregs_active. Please refer to the comment + * at the definition of fpregs_active. + */ +#define xstateregs_active fpregs_active + +#ifdef CONFIG_MATH_EMULATION +extern void finit_soft_fpu(struct i387_soft_struct *soft); +#else +static inline void finit_soft_fpu(struct i387_soft_struct *soft) {} +#endif + +/* + * Must be run with preemption disabled: this clears the fpu_owner_task, + * on this CPU. + * + * This will disable any lazy FPU state restore of the current FPU state, + * but if the current thread owns the FPU, it will still be saved by. + */ +static inline void __cpu_disable_lazy_restore(unsigned int cpu) +{ + per_cpu(fpu_owner_task, cpu) = NULL; +} + +/* + * Used to indicate that the FPU state in memory is newer than the FPU + * state in registers, and the FPU state should be reloaded next time the + * task is run. Only safe on the current task, or non-running tasks. + */ +static inline void task_disable_lazy_fpu_restore(struct task_struct *tsk) +{ + tsk->thread.fpu.last_cpu = ~0; +} + +static inline int fpu_lazy_restore(struct task_struct *new, unsigned int cpu) +{ + return new == this_cpu_read_stable(fpu_owner_task) && + cpu == new->thread.fpu.last_cpu; +} + +static inline int is_ia32_compat_frame(void) +{ + return config_enabled(CONFIG_IA32_EMULATION) && + test_thread_flag(TIF_IA32); +} + +static inline int is_ia32_frame(void) +{ + return config_enabled(CONFIG_X86_32) || is_ia32_compat_frame(); +} + +static inline int is_x32_frame(void) +{ + return config_enabled(CONFIG_X86_X32_ABI) && test_thread_flag(TIF_X32); +} + +#define X87_FSW_ES (1 << 7) /* Exception Summary */ + +static __always_inline __pure bool use_eager_fpu(void) +{ + return static_cpu_has_safe(X86_FEATURE_EAGER_FPU); +} + +static __always_inline __pure bool use_xsaveopt(void) +{ + return static_cpu_has_safe(X86_FEATURE_XSAVEOPT); +} + +static __always_inline __pure bool use_xsave(void) +{ + return static_cpu_has_safe(X86_FEATURE_XSAVE); +} + +static __always_inline __pure bool use_fxsr(void) +{ + return static_cpu_has_safe(X86_FEATURE_FXSR); +} + +static inline void fx_finit(struct i387_fxsave_struct *fx) +{ + fx->cwd = 0x37f; + fx->mxcsr = MXCSR_DEFAULT; +} + +extern void __sanitize_i387_state(struct task_struct *); + +static inline void sanitize_i387_state(struct task_struct *tsk) +{ + if (!use_xsaveopt()) + return; + __sanitize_i387_state(tsk); +} + +#define user_insn(insn, output, input...) \ +({ \ + int err; \ + asm volatile(ASM_STAC "\n" \ + "1:" #insn "\n\t" \ + "2: " ASM_CLAC "\n" \ + ".section .fixup,\"ax\"\n" \ + "3: movl $-1,%[err]\n" \ + " jmp 2b\n" \ + ".previous\n" \ + _ASM_EXTABLE(1b, 3b) \ + : [err] "=r" (err), output \ + : "0"(0), input); \ + err; \ +}) + +#define check_insn(insn, output, input...) \ +({ \ + int err; \ + asm volatile("1:" #insn "\n\t" \ + "2:\n" \ + ".section .fixup,\"ax\"\n" \ + "3: movl $-1,%[err]\n" \ + " jmp 2b\n" \ + ".previous\n" \ + _ASM_EXTABLE(1b, 3b) \ + : [err] "=r" (err), output \ + : "0"(0), input); \ + err; \ +}) + +static inline int fsave_user(struct i387_fsave_struct __user *fx) +{ + return user_insn(fnsave %[fx]; fwait, [fx] "=m" (*fx), "m" (*fx)); +} + +static inline int fxsave_user(struct i387_fxsave_struct __user *fx) +{ + if (config_enabled(CONFIG_X86_32)) + return user_insn(fxsave %[fx], [fx] "=m" (*fx), "m" (*fx)); + else if (config_enabled(CONFIG_AS_FXSAVEQ)) + return user_insn(fxsaveq %[fx], [fx] "=m" (*fx), "m" (*fx)); + + /* See comment in fpu_fxsave() below. */ + return user_insn(rex64/fxsave (%[fx]), "=m" (*fx), [fx] "R" (fx)); +} + +static inline int fxrstor_checking(struct i387_fxsave_struct *fx) +{ + if (config_enabled(CONFIG_X86_32)) + return check_insn(fxrstor %[fx], "=m" (*fx), [fx] "m" (*fx)); + else if (config_enabled(CONFIG_AS_FXSAVEQ)) + return check_insn(fxrstorq %[fx], "=m" (*fx), [fx] "m" (*fx)); + + /* See comment in fpu_fxsave() below. */ + return check_insn(rex64/fxrstor (%[fx]), "=m" (*fx), [fx] "R" (fx), + "m" (*fx)); +} + +static inline int fxrstor_user(struct i387_fxsave_struct __user *fx) +{ + if (config_enabled(CONFIG_X86_32)) + return user_insn(fxrstor %[fx], "=m" (*fx), [fx] "m" (*fx)); + else if (config_enabled(CONFIG_AS_FXSAVEQ)) + return user_insn(fxrstorq %[fx], "=m" (*fx), [fx] "m" (*fx)); + + /* See comment in fpu_fxsave() below. */ + return user_insn(rex64/fxrstor (%[fx]), "=m" (*fx), [fx] "R" (fx), + "m" (*fx)); +} + +static inline int frstor_checking(struct i387_fsave_struct *fx) +{ + return check_insn(frstor %[fx], "=m" (*fx), [fx] "m" (*fx)); +} + +static inline int frstor_user(struct i387_fsave_struct __user *fx) +{ + return user_insn(frstor %[fx], "=m" (*fx), [fx] "m" (*fx)); +} + +static inline void fpu_fxsave(struct fpu *fpu) +{ + if (config_enabled(CONFIG_X86_32)) + asm volatile( "fxsave %[fx]" : [fx] "=m" (fpu->state->fxsave)); + else if (config_enabled(CONFIG_AS_FXSAVEQ)) + asm volatile("fxsaveq %[fx]" : [fx] "=m" (fpu->state->fxsave)); + else { + /* Using "rex64; fxsave %0" is broken because, if the memory + * operand uses any extended registers for addressing, a second + * REX prefix will be generated (to the assembler, rex64 + * followed by semicolon is a separate instruction), and hence + * the 64-bitness is lost. + * + * Using "fxsaveq %0" would be the ideal choice, but is only + * supported starting with gas 2.16. + * + * Using, as a workaround, the properly prefixed form below + * isn't accepted by any binutils version so far released, + * complaining that the same type of prefix is used twice if + * an extended register is needed for addressing (fix submitted + * to mainline 2005-11-21). + * + * asm volatile("rex64/fxsave %0" : "=m" (fpu->state->fxsave)); + * + * This, however, we can work around by forcing the compiler to + * select an addressing mode that doesn't require extended + * registers. + */ + asm volatile( "rex64/fxsave (%[fx])" + : "=m" (fpu->state->fxsave) + : [fx] "R" (&fpu->state->fxsave)); + } +} + +/* + * These must be called with preempt disabled. Returns + * 'true' if the FPU state is still intact. + */ +static inline int fpu_save_init(struct fpu *fpu) +{ + if (use_xsave()) { + fpu_xsave(fpu); + + /* + * xsave header may indicate the init state of the FP. + */ + if (!(fpu->state->xsave.xsave_hdr.xstate_bv & XSTATE_FP)) + return 1; + } else if (use_fxsr()) { + fpu_fxsave(fpu); + } else { + asm volatile("fnsave %[fx]; fwait" + : [fx] "=m" (fpu->state->fsave)); + return 0; + } + + /* + * If exceptions are pending, we need to clear them so + * that we don't randomly get exceptions later. + * + * FIXME! Is this perhaps only true for the old-style + * irq13 case? Maybe we could leave the x87 state + * intact otherwise? + */ + if (unlikely(fpu->state->fxsave.swd & X87_FSW_ES)) { + asm volatile("fnclex"); + return 0; + } + return 1; +} + +static inline int __save_init_fpu(struct task_struct *tsk) +{ + return fpu_save_init(&tsk->thread.fpu); +} + +static inline int fpu_restore_checking(struct fpu *fpu) +{ + if (use_xsave()) + return fpu_xrstor_checking(&fpu->state->xsave); + else if (use_fxsr()) + return fxrstor_checking(&fpu->state->fxsave); + else + return frstor_checking(&fpu->state->fsave); +} + +static inline int restore_fpu_checking(struct task_struct *tsk) +{ + /* + * AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception is + * pending. Clear the x87 state here by setting it to fixed values. + * "m" is a random variable that should be in L1. + */ + if (unlikely(static_cpu_has_bug_safe(X86_BUG_FXSAVE_LEAK))) { + asm volatile( + "fnclex\n\t" + "emms\n\t" + "fildl %P[addr]" /* set F?P to defined value */ + : : [addr] "m" (tsk->thread.fpu.has_fpu)); + } + + return fpu_restore_checking(&tsk->thread.fpu); +} + +/* + * Software FPU state helpers. Careful: these need to + * be preemption protection *and* they need to be + * properly paired with the CR0.TS changes! + */ +static inline int __thread_has_fpu(struct task_struct *tsk) +{ + return tsk->thread.fpu.has_fpu; +} + +/* Must be paired with an 'stts' after! */ +static inline void __thread_clear_has_fpu(struct task_struct *tsk) +{ + tsk->thread.fpu.has_fpu = 0; + this_cpu_write(fpu_owner_task, NULL); +} + +/* Must be paired with a 'clts' before! */ +static inline void __thread_set_has_fpu(struct task_struct *tsk) +{ + tsk->thread.fpu.has_fpu = 1; + this_cpu_write(fpu_owner_task, tsk); +} + +/* + * Encapsulate the CR0.TS handling together with the + * software flag. + * + * These generally need preemption protection to work, + * do try to avoid using these on their own. + */ +static inline void __thread_fpu_end(struct task_struct *tsk) +{ + __thread_clear_has_fpu(tsk); + if (!use_eager_fpu()) + stts(); +} + +static inline void __thread_fpu_begin(struct task_struct *tsk) +{ + if (!use_eager_fpu()) + clts(); + __thread_set_has_fpu(tsk); +} + +static inline void drop_fpu(struct task_struct *tsk) +{ + /* + * Forget coprocessor state.. + */ + preempt_disable(); + tsk->thread.fpu_counter = 0; + + if (__thread_has_fpu(tsk)) { + /* Ignore delayed exceptions from user space */ + asm volatile("1: fwait\n" + "2:\n" + _ASM_EXTABLE(1b, 2b)); + __thread_fpu_end(tsk); + } + + clear_stopped_child_used_math(tsk); + preempt_enable(); +} + +static inline void restore_init_xstate(void) +{ + if (use_xsave()) + xrstor_state(init_xstate_buf, -1); + else + fxrstor_checking(&init_xstate_buf->i387); +} + +/* + * Reset the FPU state in the eager case and drop it in the lazy case (later use + * will reinit it). + */ +static inline void fpu_reset_state(struct task_struct *tsk) +{ + if (!use_eager_fpu()) + drop_fpu(tsk); + else + restore_init_xstate(); +} + +/* + * FPU state switching for scheduling. + * + * This is a two-stage process: + * + * - switch_fpu_prepare() saves the old state and + * sets the new state of the CR0.TS bit. This is + * done within the context of the old process. + * + * - switch_fpu_finish() restores the new state as + * necessary. + */ +typedef struct { int preload; } fpu_switch_t; + +static inline fpu_switch_t switch_fpu_prepare(struct task_struct *old, struct task_struct *new, int cpu) +{ + fpu_switch_t fpu; + + /* + * If the task has used the math, pre-load the FPU on xsave processors + * or if the past 5 consecutive context-switches used math. + */ + fpu.preload = tsk_used_math(new) && + (use_eager_fpu() || new->thread.fpu_counter > 5); + + if (__thread_has_fpu(old)) { + if (!__save_init_fpu(old)) + task_disable_lazy_fpu_restore(old); + else + old->thread.fpu.last_cpu = cpu; + + /* But leave fpu_owner_task! */ + old->thread.fpu.has_fpu = 0; + + /* Don't change CR0.TS if we just switch! */ + if (fpu.preload) { + new->thread.fpu_counter++; + __thread_set_has_fpu(new); + prefetch(new->thread.fpu.state); + } else if (!use_eager_fpu()) + stts(); + } else { + old->thread.fpu_counter = 0; + task_disable_lazy_fpu_restore(old); + if (fpu.preload) { + new->thread.fpu_counter++; + if (fpu_lazy_restore(new, cpu)) + fpu.preload = 0; + else + prefetch(new->thread.fpu.state); + __thread_fpu_begin(new); + } + } + return fpu; +} + +/* + * By the time this gets called, we've already cleared CR0.TS and + * given the process the FPU if we are going to preload the FPU + * state - all we need to do is to conditionally restore the register + * state itself. + */ +static inline void switch_fpu_finish(struct task_struct *new, fpu_switch_t fpu) +{ + if (fpu.preload) { + if (unlikely(restore_fpu_checking(new))) + fpu_reset_state(new); + } +} + +/* + * Signal frame handlers... + */ +extern int save_xstate_sig(void __user *buf, void __user *fx, int size); +extern int __restore_xstate_sig(void __user *buf, void __user *fx, int size); + +static inline int xstate_sigframe_size(void) +{ + return use_xsave() ? xstate_size + FP_XSTATE_MAGIC2_SIZE : xstate_size; +} + +static inline int restore_xstate_sig(void __user *buf, int ia32_frame) +{ + void __user *buf_fx = buf; + int size = xstate_sigframe_size(); + + if (ia32_frame && use_fxsr()) { + buf_fx = buf + sizeof(struct i387_fsave_struct); + size += sizeof(struct i387_fsave_struct); + } + + return __restore_xstate_sig(buf, buf_fx, size); +} + +/* + * Needs to be preemption-safe. + * + * NOTE! user_fpu_begin() must be used only immediately before restoring + * the save state. It does not do any saving/restoring on its own. In + * lazy FPU mode, it is just an optimization to avoid a #NM exception, + * the task can lose the FPU right after preempt_enable(). + */ +static inline void user_fpu_begin(void) +{ + preempt_disable(); + if (!user_has_fpu()) + __thread_fpu_begin(current); + preempt_enable(); +} + +static inline void __save_fpu(struct task_struct *tsk) +{ + if (use_xsave()) { + if (unlikely(system_state == SYSTEM_BOOTING)) + xsave_state_booting(&tsk->thread.fpu.state->xsave, -1); + else + xsave_state(&tsk->thread.fpu.state->xsave, -1); + } else + fpu_fxsave(&tsk->thread.fpu); +} + +/* + * i387 state interaction + */ +static inline unsigned short get_fpu_cwd(struct task_struct *tsk) +{ + if (cpu_has_fxsr) { + return tsk->thread.fpu.state->fxsave.cwd; + } else { + return (unsigned short)tsk->thread.fpu.state->fsave.cwd; + } +} + +static inline unsigned short get_fpu_swd(struct task_struct *tsk) +{ + if (cpu_has_fxsr) { + return tsk->thread.fpu.state->fxsave.swd; + } else { + return (unsigned short)tsk->thread.fpu.state->fsave.swd; + } +} + +static inline unsigned short get_fpu_mxcsr(struct task_struct *tsk) +{ + if (cpu_has_xmm) { + return tsk->thread.fpu.state->fxsave.mxcsr; + } else { + return MXCSR_DEFAULT; + } +} + +static bool fpu_allocated(struct fpu *fpu) +{ + return fpu->state != NULL; +} + +static inline int fpu_alloc(struct fpu *fpu) +{ + if (fpu_allocated(fpu)) + return 0; + fpu->state = kmem_cache_alloc(task_xstate_cachep, GFP_KERNEL); + if (!fpu->state) + return -ENOMEM; + WARN_ON((unsigned long)fpu->state & 15); + return 0; +} + +static inline void fpu_free(struct fpu *fpu) +{ + if (fpu->state) { + kmem_cache_free(task_xstate_cachep, fpu->state); + fpu->state = NULL; + } +} + +static inline void fpu_copy(struct task_struct *dst, struct task_struct *src) +{ + if (use_eager_fpu()) { + memset(&dst->thread.fpu.state->xsave, 0, xstate_size); + __save_fpu(dst); + } else { + struct fpu *dfpu = &dst->thread.fpu; + struct fpu *sfpu = &src->thread.fpu; + + unlazy_fpu(src); + memcpy(dfpu->state, sfpu->state, xstate_size); + } +} + +static inline unsigned long +alloc_mathframe(unsigned long sp, int ia32_frame, unsigned long *buf_fx, + unsigned long *size) +{ + unsigned long frame_size = xstate_sigframe_size(); + + *buf_fx = sp = round_down(sp - frame_size, 64); + if (ia32_frame && use_fxsr()) { + frame_size += sizeof(struct i387_fsave_struct); + sp -= sizeof(struct i387_fsave_struct); + } + + *size = frame_size; + return sp; +} + +#endif -- cgit 1.2.3-korg