kernel/include/linux/context_tracking.h

   1 #ifndef _LINUX_CONTEXT_TRACKING_H
   2 #define _LINUX_CONTEXT_TRACKING_H
   3
   4 #include <linux/sched.h>
   5 #include <linux/vtime.h>
   6 #include <linux/context_tracking_state.h>
   7 #include <asm/ptrace.h>
   8
   9
  10 #ifdef CONFIG_CONTEXT_TRACKING
  11 extern void context_tracking_cpu_set(int cpu);
  12
  13 extern void context_tracking_enter(enum ctx_state state);
  14 extern void context_tracking_exit(enum ctx_state state);
  15 extern void context_tracking_user_enter(void);
  16 extern void context_tracking_user_exit(void);
  17 extern void __context_tracking_task_switch(struct task_struct *prev,
  18                                            struct task_struct *next);
  19
  20 static inline void user_enter(void)
  21 {
  22         if (context_tracking_is_enabled())
  23                 context_tracking_user_enter();
  24
  25 }
  26 static inline void user_exit(void)
  27 {
  28         if (context_tracking_is_enabled())
  29                 context_tracking_user_exit();
  30 }
  31
  32 static inline enum ctx_state exception_enter(void)
  33 {
  34         enum ctx_state prev_ctx;
  35
  36         if (!context_tracking_is_enabled())
  37                 return 0;
  38
  39         prev_ctx = this_cpu_read(context_tracking.state);
  40         if (prev_ctx != CONTEXT_KERNEL)
  41                 context_tracking_exit(prev_ctx);
  42
  43         return prev_ctx;
  44 }
  45
  46 static inline void exception_exit(enum ctx_state prev_ctx)
  47 {
  48         if (context_tracking_is_enabled()) {
  49                 if (prev_ctx != CONTEXT_KERNEL)
  50                         context_tracking_enter(prev_ctx);
  51         }
  52 }
  53
  54 static inline void context_tracking_task_switch(struct task_struct *prev,
  55                                                 struct task_struct *next)
  56 {
  57         if (context_tracking_is_enabled())
  58                 __context_tracking_task_switch(prev, next);
  59 }
  60 #else
  61 static inline void user_enter(void) { }
  62 static inline void user_exit(void) { }
  63 static inline enum ctx_state exception_enter(void) { return 0; }
  64 static inline void exception_exit(enum ctx_state prev_ctx) { }
  65 static inline void context_tracking_task_switch(struct task_struct *prev,
  66                                                 struct task_struct *next) { }
  67 #endif /* !CONFIG_CONTEXT_TRACKING */
  68
  69
  70 #ifdef CONFIG_CONTEXT_TRACKING_FORCE
  71 extern void context_tracking_init(void);
  72 #else
  73 static inline void context_tracking_init(void) { }
  74 #endif /* CONFIG_CONTEXT_TRACKING_FORCE */
  75
  76
  77 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
  78 static inline void guest_enter(void)
  79 {
  80         if (vtime_accounting_enabled())
  81                 vtime_guest_enter(current);
  82         else
  83                 current->flags |= PF_VCPU;
  84
  85         if (context_tracking_is_enabled())
  86                 context_tracking_enter(CONTEXT_GUEST);
  87 }
  88
  89 static inline void guest_exit(void)
  90 {
  91         if (context_tracking_is_enabled())
  92                 context_tracking_exit(CONTEXT_GUEST);
  93
  94         if (vtime_accounting_enabled())
  95                 vtime_guest_exit(current);
  96         else
  97                 current->flags &= ~PF_VCPU;
  98 }
  99
 100 #else
 101 static inline void guest_enter(void)
 102 {
 103         /*
 104          * This is running in ioctl context so its safe
 105          * to assume that it's the stime pending cputime
 106          * to flush.
 107          */
 108         vtime_account_system(current);
 109         current->flags |= PF_VCPU;
 110 }
 111
 112 static inline void guest_exit(void)
 113 {
 114         /* Flush the guest cputime we spent on the guest */
 115         vtime_account_system(current);
 116         current->flags &= ~PF_VCPU;
 117 }
 118 #endif /* CONFIG_VIRT_CPU_ACCOUNTING_GEN */
 119
 120 #endif