taglinefilesource code
freeswap280fs/proc/array.ci.totalswap, i.totalswap-i.freeswap, i.freeswap);
freeswap81include/linux/kernel.hunsigned long freeswap;    /* swap space still available */
freeswap1277mm/swap.cval->freeswap = val->totalswap = 0;
freeswap1286mm/swap.c++val->freeswap;
freeswap1291mm/swap.cval->freeswap <<= PAGE_SHIFT;