From b1b64dc3558b7bde2917f9fc4f573f6a4787a95c Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Tue, 5 May 2015 15:56:33 +0200 Subject: [PATCH] x86/fpu: Reorganize fpu/internal.h fpu/internal.h has grown organically, with not much high level structure, which hurts its readability. Organize the various definitions into 5 sections: - high level FPU state functions - FPU/CPU feature flag helpers - fpstate handling functions - FPU context switching helpers - misc helper functions Other related changes: - Move MXCSR_DEFAULT to fpu/types.h. - drop the unused X87_FSW_ES define No change in functionality. Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Thomas Gleixner Signed-off-by: Ingo Molnar --- arch/x86/include/asm/fpu/internal.h | 159 +++++++++++++++------------- arch/x86/include/asm/fpu/types.h | 3 + 2 files changed, 87 insertions(+), 75 deletions(-) diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h index d2a281bd5f45..a98a08d1efa9 100644 --- a/arch/x86/include/asm/fpu/internal.h +++ b/arch/x86/include/asm/fpu/internal.h @@ -18,32 +18,6 @@ #include #include -#define MXCSR_DEFAULT 0x1f80 - -extern unsigned int mxcsr_feature_mask; - -extern union fpregs_state init_fpstate; - -extern void fpu__init_cpu(void); -extern void fpu__init_system_xstate(void); -extern void fpu__init_cpu_xstate(void); -extern void fpu__init_system(struct cpuinfo_x86 *c); - -extern void fpstate_init(union fpregs_state *state); -#ifdef CONFIG_MATH_EMULATION -extern void fpstate_init_soft(struct swregs_state *soft); -#else -static inline void fpstate_init_soft(struct swregs_state *soft) {} -#endif -static inline void fpstate_init_fxstate(struct fxregs_state *fx) -{ - fx->cwd = 0x37f; - fx->mxcsr = MXCSR_DEFAULT; -} - -extern int dump_fpu(struct pt_regs *, struct user_i387_struct *); -extern int fpu__exception_code(struct fpu *fpu, int trap_nr); - /* * High level FPU state handling functions: */ @@ -55,7 +29,16 @@ extern int fpu__restore_sig(void __user *buf, int ia32_frame); extern void fpu__drop(struct fpu *fpu); extern int fpu__copy(struct fpu *dst_fpu, struct fpu *src_fpu); extern void fpu__clear(struct fpu *fpu); +extern int fpu__exception_code(struct fpu *fpu, int trap_nr); +extern int dump_fpu(struct pt_regs *ptregs, struct user_i387_struct *fpstate); +/* + * Boot time FPU initialization functions: + */ +extern void fpu__init_cpu(void); +extern void fpu__init_system_xstate(void); +extern void fpu__init_cpu_xstate(void); +extern void fpu__init_system(struct cpuinfo_x86 *c); extern void fpu__init_check_bugs(void); extern void fpu__resume_cpu(void); @@ -68,27 +51,9 @@ extern void fpu__resume_cpu(void); # define WARN_ON_FPU(x) ({ 0; }) #endif -DECLARE_PER_CPU(struct fpu *, fpu_fpregs_owner_ctx); - /* - * Must be run with preemption disabled: this clears the fpu_fpregs_owner_ctx, - * 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. + * FPU related CPU feature flag helper routines: */ -static inline void __cpu_disable_lazy_restore(unsigned int cpu) -{ - per_cpu(fpu_fpregs_owner_ctx, cpu) = NULL; -} - -static inline int fpu_want_lazy_restore(struct fpu *fpu, unsigned int cpu) -{ - return fpu == this_cpu_read_stable(fpu_fpregs_owner_ctx) && cpu == fpu->last_cpu; -} - -#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); @@ -109,6 +74,23 @@ static __always_inline __pure bool use_fxsr(void) return static_cpu_has_safe(X86_FEATURE_FXSR); } +/* + * fpstate handling functions: + */ + +extern union fpregs_state init_fpstate; + +extern void fpstate_init(union fpregs_state *state); +#ifdef CONFIG_MATH_EMULATION +extern void fpstate_init_soft(struct swregs_state *soft); +#else +static inline void fpstate_init_soft(struct swregs_state *soft) {} +#endif +static inline void fpstate_init_fxstate(struct fxregs_state *fx) +{ + fx->cwd = 0x37f; + fx->mxcsr = MXCSR_DEFAULT; +} extern void fpstate_sanitize_xstate(struct fpu *fpu); #define user_insn(insn, output, input...) \ @@ -285,6 +267,32 @@ static inline int copy_fpstate_to_fpregs(struct fpu *fpu) return __copy_fpstate_to_fpregs(fpu); } +extern int copy_fpstate_to_sigframe(void __user *buf, void __user *fx, int size); + +/* + * FPU context switch related helper methods: + */ + +DECLARE_PER_CPU(struct fpu *, fpu_fpregs_owner_ctx); + +/* + * Must be run with preemption disabled: this clears the fpu_fpregs_owner_ctx, + * 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_fpregs_owner_ctx, cpu) = NULL; +} + +static inline int fpu_want_lazy_restore(struct fpu *fpu, unsigned int cpu) +{ + return fpu == this_cpu_read_stable(fpu_fpregs_owner_ctx) && cpu == fpu->last_cpu; +} + + /* * Wrap lazy FPU TS handling in a 'hw fpregs activation/deactivation' * idiom, which is then paired with the sw-flag (fpregs_active) later on: @@ -354,31 +362,6 @@ static inline void fpregs_deactivate(struct fpu *fpu) __fpregs_deactivate_hw(); } -/* - * Definitions for the eXtended Control Register instructions - */ - -#define XCR_XFEATURE_ENABLED_MASK 0x00000000 - -static inline u64 xgetbv(u32 index) -{ - u32 eax, edx; - - asm volatile(".byte 0x0f,0x01,0xd0" /* xgetbv */ - : "=a" (eax), "=d" (edx) - : "c" (index)); - return eax + ((u64)edx << 32); -} - -static inline void xsetbv(u32 index, u64 value) -{ - u32 eax = value; - u32 edx = value >> 32; - - asm volatile(".byte 0x0f,0x01,0xd1" /* xsetbv */ - : : "a" (eax), "d" (edx), "c" (index)); -} - /* * FPU state switching for scheduling. * @@ -437,6 +420,10 @@ switch_fpu_prepare(struct fpu *old_fpu, struct fpu *new_fpu, int cpu) return fpu; } +/* + * Misc helper functions: + */ + /* * 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 @@ -453,11 +440,6 @@ static inline void switch_fpu_finish(struct fpu *new_fpu, fpu_switch_t fpu_switc } } -/* - * Signal frame handlers... - */ -extern int copy_fpstate_to_sigframe(void __user *buf, void __user *fx, int size); - /* * Needs to be preemption-safe. * @@ -476,4 +458,31 @@ static inline void user_fpu_begin(void) preempt_enable(); } +/* + * MXCSR and XCR definitions: + */ + +extern unsigned int mxcsr_feature_mask; + +#define XCR_XFEATURE_ENABLED_MASK 0x00000000 + +static inline u64 xgetbv(u32 index) +{ + u32 eax, edx; + + asm volatile(".byte 0x0f,0x01,0xd0" /* xgetbv */ + : "=a" (eax), "=d" (edx) + : "c" (index)); + return eax + ((u64)edx << 32); +} + +static inline void xsetbv(u32 index, u64 value) +{ + u32 eax = value; + u32 edx = value >> 32; + + asm volatile(".byte 0x0f,0x01,0xd1" /* xsetbv */ + : : "a" (eax), "d" (edx), "c" (index)); +} + #endif /* _ASM_X86_FPU_INTERNAL_H */ diff --git a/arch/x86/include/asm/fpu/types.h b/arch/x86/include/asm/fpu/types.h index 02241c2a10e9..0637826292de 100644 --- a/arch/x86/include/asm/fpu/types.h +++ b/arch/x86/include/asm/fpu/types.h @@ -65,6 +65,9 @@ struct fxregs_state { } __attribute__((aligned(16))); +/* Default value for fxregs_state.mxcsr: */ +#define MXCSR_DEFAULT 0x1f80 + /* * Software based FPU emulation state. This is arbitrary really, * it matches the x87 format to make it easier to understand: -- 2.20.1