SWAP_USAGE_OFFLIST_BIT
atomic_long_or(SWAP_USAGE_OFFLIST_BIT, &si->inuse_pages);
pages | SWAP_USAGE_OFFLIST_BIT))
if (!(atomic_long_read(&si->inuse_pages) & SWAP_USAGE_OFFLIST_BIT))
val = atomic_long_fetch_and_relaxed(~SWAP_USAGE_OFFLIST_BIT, &si->inuse_pages);
pages | SWAP_USAGE_OFFLIST_BIT))
if (unlikely(val & SWAP_USAGE_OFFLIST_BIT))
#define SWAP_USAGE_COUNTER_MASK (~SWAP_USAGE_OFFLIST_BIT)
atomic_long_set(&p->inuse_pages, SWAP_USAGE_OFFLIST_BIT);