From 53dc80287da43b75df2fe2658651d3c5160dad8e Mon Sep 17 00:00:00 2001 From: Atsushi Nemoto Date: Sat, 10 Mar 2007 01:07:45 +0900 Subject: [MIPS] FPU ownership management & preemption fixes Signed-off-by: Atsushi Nemoto Signed-off-by: Ralf Baechle --- include/asm-mips/cpu-features.h | 3 +++ include/asm-mips/cpu-info.h | 1 + include/asm-mips/fpu.h | 54 ++++++++++++++++++++++++++++++++--------- include/asm-mips/thread_info.h | 1 + 4 files changed, 48 insertions(+), 11 deletions(-) (limited to 'include') diff --git a/include/asm-mips/cpu-features.h b/include/asm-mips/cpu-features.h index eadca266f159..5e4bed123b48 100644 --- a/include/asm-mips/cpu-features.h +++ b/include/asm-mips/cpu-features.h @@ -40,6 +40,9 @@ #endif #ifndef cpu_has_fpu #define cpu_has_fpu (current_cpu_data.options & MIPS_CPU_FPU) +#define raw_cpu_has_fpu (raw_current_cpu_data.options & MIPS_CPU_FPU) +#else +#define raw_cpu_has_fpu cpu_has_fpu #endif #ifndef cpu_has_32fpr #define cpu_has_32fpr (cpu_data[0].options & MIPS_CPU_32FPR) diff --git a/include/asm-mips/cpu-info.h b/include/asm-mips/cpu-info.h index 610d0cdeaa9e..22fe8453fcc7 100644 --- a/include/asm-mips/cpu-info.h +++ b/include/asm-mips/cpu-info.h @@ -87,6 +87,7 @@ struct cpuinfo_mips { extern struct cpuinfo_mips cpu_data[]; #define current_cpu_data cpu_data[smp_processor_id()] +#define raw_current_cpu_data cpu_data[raw_smp_processor_id()] extern void cpu_probe(void); extern void cpu_report(void); diff --git a/include/asm-mips/fpu.h b/include/asm-mips/fpu.h index efef843b93f0..4e12d1f9534f 100644 --- a/include/asm-mips/fpu.h +++ b/include/asm-mips/fpu.h @@ -27,11 +27,11 @@ struct sigcontext; struct sigcontext32; -extern asmlinkage int (*save_fp_context)(struct sigcontext *sc); -extern asmlinkage int (*restore_fp_context)(struct sigcontext *sc); +extern asmlinkage int (*save_fp_context)(struct sigcontext __user *sc); +extern asmlinkage int (*restore_fp_context)(struct sigcontext __user *sc); -extern asmlinkage int (*save_fp_context32)(struct sigcontext32 *sc); -extern asmlinkage int (*restore_fp_context32)(struct sigcontext32 *sc); +extern asmlinkage int (*save_fp_context32)(struct sigcontext32 __user *sc); +extern asmlinkage int (*restore_fp_context32)(struct sigcontext32 __user *sc); extern void fpu_emulator_init_fpu(void); extern void _init_fpu(void); @@ -68,6 +68,8 @@ do { \ /* We don't care about the c0 hazard here */ \ } while (0) +#define __fpu_enabled() (read_c0_status() & ST0_CU1) + #define enable_fpu() \ do { \ if (cpu_has_fpu) \ @@ -93,31 +95,47 @@ static inline int is_fpu_owner(void) return cpu_has_fpu && __is_fpu_owner(); } -static inline void own_fpu(void) +static inline void __own_fpu(void) { - if (cpu_has_fpu) { - __enable_fpu(); - KSTK_STATUS(current) |= ST0_CU1; - set_thread_flag(TIF_USEDFPU); + __enable_fpu(); + KSTK_STATUS(current) |= ST0_CU1; + set_thread_flag(TIF_USEDFPU); +} + +static inline void own_fpu(int restore) +{ + preempt_disable(); + if (cpu_has_fpu && !__is_fpu_owner()) { + __own_fpu(); + if (restore) + _restore_fp(current); } + preempt_enable(); } -static inline void lose_fpu(void) +static inline void lose_fpu(int save) { - if (cpu_has_fpu) { + preempt_disable(); + if (is_fpu_owner()) { + if (save) + _save_fp(current); KSTK_STATUS(current) &= ~ST0_CU1; clear_thread_flag(TIF_USEDFPU); __disable_fpu(); } + preempt_enable(); } static inline void init_fpu(void) { + preempt_disable(); if (cpu_has_fpu) { + __own_fpu(); _init_fpu(); } else { fpu_emulator_init_fpu(); } + preempt_enable(); } static inline void save_fp(struct task_struct *tsk) @@ -144,4 +162,18 @@ static inline fpureg_t *get_fpu_regs(struct task_struct *tsk) return tsk->thread.fpu.fpr; } +static inline void enable_fp_in_kernel(void) +{ + set_thread_flag(TIF_ALLOW_FP_IN_KERNEL); + /* make sure CU1 and FPU ownership are consistent */ + if (!__is_fpu_owner() && __fpu_enabled()) + __disable_fpu(); +} + +static inline void disable_fp_in_kernel(void) +{ + BUG_ON(!__is_fpu_owner() && __fpu_enabled()); + clear_thread_flag(TIF_ALLOW_FP_IN_KERNEL); +} + #endif /* _ASM_FPU_H */ diff --git a/include/asm-mips/thread_info.h b/include/asm-mips/thread_info.h index fbcda8204473..6cf05f4a4e7e 100644 --- a/include/asm-mips/thread_info.h +++ b/include/asm-mips/thread_info.h @@ -119,6 +119,7 @@ register struct thread_info *__current_thread_info __asm__("$28"); #define TIF_POLLING_NRFLAG 17 /* true if poll_idle() is polling TIF_NEED_RESCHED */ #define TIF_MEMDIE 18 #define TIF_FREEZE 19 +#define TIF_ALLOW_FP_IN_KERNEL 20 #define TIF_SYSCALL_TRACE 31 /* syscall trace active */ #define _TIF_SYSCALL_TRACE (1<