diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/asm-x86_64/i387.h | 5 | ||||
| -rw-r--r-- | include/linux/sched.h | 9 |
2 files changed, 13 insertions, 1 deletions
diff --git a/include/asm-x86_64/i387.h b/include/asm-x86_64/i387.h index cba8a3b0cded5..60c0f4853fdbd 100644 --- a/include/asm-x86_64/i387.h +++ b/include/asm-x86_64/i387.h @@ -24,6 +24,7 @@ extern unsigned int mxcsr_feature_mask; extern void mxcsr_feature_mask_init(void); extern void init_fpu(struct task_struct *child); extern int save_i387(struct _fpstate __user *buf); +extern asmlinkage void math_state_restore(void); /* * FPU lazy state save handling... @@ -31,7 +32,9 @@ extern int save_i387(struct _fpstate __user *buf); #define unlazy_fpu(tsk) do { \ if (task_thread_info(tsk)->status & TS_USEDFPU) \ - save_init_fpu(tsk); \ + save_init_fpu(tsk); \ + else \ + tsk->fpu_counter = 0; \ } while (0) /* Ignore delayed exceptions from user space */ diff --git a/include/linux/sched.h b/include/linux/sched.h index 34ed0d99b1bd1..807556c5bcd26 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -865,6 +865,15 @@ struct task_struct { struct key *thread_keyring; /* keyring private to this thread */ unsigned char jit_keyring; /* default keyring to attach requested keys to */ #endif + /* + * fpu_counter contains the number of consecutive context switches + * that the FPU is used. If this is over a threshold, the lazy fpu + * saving becomes unlazy to save the trap. This is an unsigned char + * so that after 256 times the counter wraps and the behavior turns + * lazy again; this to deal with bursty apps that only use FPU for + * a short time + */ + unsigned char fpu_counter; int oomkilladj; /* OOM kill score adjustment (bit shift). */ char comm[TASK_COMM_LEN]; /* executable name excluding path - access with [gs]et_task_comm (which lock |