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_enter(enum ctx_state state);
  14extern void context_tracking_exit(enum ctx_state state);
  15extern void context_tracking_user_enter(void);
  16extern void context_tracking_user_exit(void);
  17extern void __context_tracking_task_switch(struct task_struct *prev,
  18                                           struct task_struct *next);
  19
  20static inline void user_enter(void)
  21{
  22        if (context_tracking_is_enabled())
  23                context_tracking_user_enter();
  24
  25}
  26static inline void user_exit(void)
  27{
  28        if (context_tracking_is_enabled())
  29                context_tracking_user_exit();
  30}
  31
  32static 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
  46static 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
  54static 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
  61static inline void user_enter(void) { }
  62static inline void user_exit(void) { }
  63static inline enum ctx_state exception_enter(void) { return 0; }
  64static inline void exception_exit(enum ctx_state prev_ctx) { }
  65static 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
  71extern void context_tracking_init(void);
  72#else
  73static inline void context_tracking_init(void) { }
  74#endif /* CONFIG_CONTEXT_TRACKING_FORCE */
  75
  76
  77#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
  78static 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
  89static 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
 101static 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
 112static 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
 121