static DEFINE_SPINLOCK(swap_token_lock);
struct mm_struct *swap_token_mm;
-unsigned int global_faults;
+static unsigned int global_faults;
-void grab_swap_token(void)
+void grab_swap_token(struct mm_struct *mm)
{
int current_interval;
global_faults++;
- current_interval = global_faults - current->mm->faultstamp;
+ current_interval = global_faults - mm->faultstamp;
if (!spin_trylock(&swap_token_lock))
return;
/* First come first served */
if (swap_token_mm == NULL) {
- current->mm->token_priority = current->mm->token_priority + 2;
- swap_token_mm = current->mm;
+ mm->token_priority = mm->token_priority + 2;
+ swap_token_mm = mm;
goto out;
}
- if (current->mm != swap_token_mm) {
- if (current_interval < current->mm->last_interval)
- current->mm->token_priority++;
+ if (mm != swap_token_mm) {
+ if (current_interval < mm->last_interval)
+ mm->token_priority++;
else {
- current->mm->token_priority--;
- if (unlikely(current->mm->token_priority < 0))
- current->mm->token_priority = 0;
+ if (likely(mm->token_priority > 0))
+ mm->token_priority--;
}
/* Check if we deserve the token */
- if (current->mm->token_priority >
- swap_token_mm->token_priority) {
- current->mm->token_priority += 2;
- swap_token_mm = current->mm;
+ if (mm->token_priority > swap_token_mm->token_priority) {
+ mm->token_priority += 2;
+ swap_token_mm = mm;
}
} else {
/* Token holder came in again! */
- current->mm->token_priority += 2;
+ mm->token_priority += 2;
}
out:
- current->mm->faultstamp = global_faults;
- current->mm->last_interval = current_interval;
+ mm->faultstamp = global_faults;
+ mm->last_interval = current_interval;
spin_unlock(&swap_token_lock);
-return;
}
/* Called on process exit. */