LXR linux/include/linux/context

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