diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/asm-arm26/constants.h | 1 | ||||
| -rw-r--r-- | include/asm-x86_64/i387.h | 10 | ||||
| -rw-r--r-- | include/linux/sched.h | 43 |
3 files changed, 28 insertions, 26 deletions
diff --git a/include/asm-arm26/constants.h b/include/asm-arm26/constants.h index 47c65cae7e6a..0d0b14415563 100644 --- a/include/asm-arm26/constants.h +++ b/include/asm-arm26/constants.h @@ -7,7 +7,6 @@ * */ -#define TSK_USED_MATH 788 /* offsetof(struct task_struct, used_math) */ #define TSK_ACTIVE_MM 96 /* offsetof(struct task_struct, active_mm) */ #define VMA_VM_MM 0 /* offsetof(struct vm_area_struct, vm_mm) */ diff --git a/include/asm-x86_64/i387.h b/include/asm-x86_64/i387.h index e613b8b164e4..aa39cfd0e001 100644 --- a/include/asm-x86_64/i387.h +++ b/include/asm-x86_64/i387.h @@ -25,16 +25,6 @@ extern void mxcsr_feature_mask_init(void); extern void init_fpu(struct task_struct *child); extern int save_i387(struct _fpstate __user *buf); -static inline int need_signal_i387(struct task_struct *me) -{ - if (!me->used_math) - return 0; - me->used_math = 0; - if (me->thread_info->status & TS_USEDFPU) - return 0; - return 1; -} - /* * FPU lazy state save handling... */ diff --git a/include/linux/sched.h b/include/linux/sched.h index cf7394b25af5..1f4ccd433ce9 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -614,19 +614,7 @@ struct task_struct { struct key *process_keyring; /* keyring private to this process (CLONE_THREAD) */ struct key *thread_keyring; /* keyring private to this thread */ #endif -/* - * Must be changed atomically so it shouldn't be - * be a shareable bitflag. - */ - unsigned char used_math; -/* - * OOM kill score adjustment (bit shift). - * Cannot live together with used_math since - * used_math and oomkilladj can be changed at the - * same time, so they would race if they're in the - * same atomic block. - */ - short oomkilladj; + int oomkilladj; /* OOM kill score adjustment (bit shift). */ char comm[TASK_COMM_LEN]; /* file system info */ int link_count, total_link_count; @@ -695,7 +683,7 @@ struct task_struct { #endif #ifdef CONFIG_NUMA struct mempolicy *mempolicy; - short il_next; /* could be shared with used_math */ + short il_next; #endif }; @@ -737,7 +725,7 @@ do { if (atomic_dec_and_test(&(tsk)->usage)) __put_task_struct(tsk); } while(0) #define PF_SIGNALED 0x00000400 /* killed by a signal */ #define PF_MEMALLOC 0x00000800 /* Allocating memory */ #define PF_FLUSHER 0x00001000 /* responsible for disk writeback */ - +#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */ #define PF_FREEZE 0x00004000 /* this task is being frozen for suspend now */ #define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */ #define PF_FROZEN 0x00010000 /* frozen for system suspend */ @@ -748,6 +736,31 @@ do { if (atomic_dec_and_test(&(tsk)->usage)) __put_task_struct(tsk); } while(0) #define PF_SYNCWRITE 0x00200000 /* I am doing a sync write */ #define PF_BORROWED_MM 0x00400000 /* I am a kthread doing use_mm */ +/* + * Only the _current_ task can read/write to tsk->flags, but other + * tasks can access tsk->flags in readonly mode for example + * with tsk_used_math (like during threaded core dumping). + * There is however an exception to this rule during ptrace + * or during fork: the ptracer task is allowed to write to the + * child->flags of its traced child (same goes for fork, the parent + * can write to the child->flags), because we're guaranteed the + * child is not running and in turn not changing child->flags + * at the same time the parent does it. + */ +#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) +#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) +#define clear_used_math() clear_stopped_child_used_math(current) +#define set_used_math() set_stopped_child_used_math(current) +#define conditional_stopped_child_used_math(condition, child) \ + do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) +#define conditional_used_math(condition) \ + conditional_stopped_child_used_math(condition, current) +#define copy_to_stopped_child_used_math(child) \ + do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) +/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ +#define tsk_used_math(p) ((p)->flags & PF_USED_MATH) +#define used_math() tsk_used_math(current) + #ifdef CONFIG_SMP extern int set_cpus_allowed(task_t *p, cpumask_t new_mask); #else |