page_cpupid_xchg

#endif
 
#ifdef CONFIG_NUMA_BALANCING
static inline int cpu_pid_to_cpupid(int cpu, int pid)
{
    return ((cpu & LAST__CPU_MASK) << LAST__PID_SHIFT) | (pid & LAST__PID_MASK);
}
 
static inline int cpupid_to_pid(int cpupid)
{
    return cpupid & LAST__PID_MASK;
}
 
static inline int cpupid_to_cpu(int cpupid)
{
    return (cpupid >> LAST__PID_SHIFT) & LAST__CPU_MASK;
}
 
static inline int cpupid_to_nid(int cpupid)
{
    return cpu_to_node(cpupid_to_cpu(cpupid));
}
 
static inline bool cpupid_pid_unset(int cpupid)
{
    return cpupid_to_pid(cpupid) == (-1 & LAST__PID_MASK);
}
 
static inline bool cpupid_cpu_unset(int cpupid)
{
    return cpupid_to_cpu(cpupid) == (-1 & LAST__CPU_MASK);
}
 
static inline bool __cpupid_match_pid(pid_t task_pid, int cpupid)
{
    return (task_pid & LAST__PID_MASK) == cpupid_to_pid(cpupid);
}
 
#define cpupid_match_pid(task, cpupid) __cpupid_match_pid(task->pid, cpupid)
#ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
{
    return xchg(&page->_last_cpupid, cpupid & LAST_CPUPID_MASK);
}
 
static inline int page_cpupid_last(struct page *page)
{
    return page->_last_cpupid;
}
static inline void page_cpupid_reset_last(struct page *page)
{
    page->_last_cpupid = -1 & LAST_CPUPID_MASK;
}
#else
static inline int page_cpupid_last(struct page *page)
{
    return (page->flags >> LAST_CPUPID_PGSHIFT) & LAST_CPUPID_MASK;
}
 
extern int page_cpupid_xchg_last(struct page *page, int cpupid);
 
static inline void page_cpupid_reset_last(struct page *page)
{
    page->flags |= LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT;
}
#endif /* LAST_CPUPID_NOT_IN_PAGE_FLAGS */
#else /* !CONFIG_NUMA_BALANCING */
static inline int page_cpupid_xchg_last(struct page *page, int cpupid)
{
    return page_to_nid(page); /* XXX */
}
函数源码
