PF_KSWAPD
if (WARN_ON_ONCE((current->flags & (PF_MEMALLOC | PF_KSWAPD)) ==
new_pflags |= PF_MEMALLOC | PF_KSWAPD;
return current->flags & PF_KSWAPD;
tsk->flags |= PF_MEMALLOC | PF_KSWAPD;
tsk->flags &= ~(PF_MEMALLOC | PF_KSWAPD);