percpu_counter_read
percpu_counter_read(&EXT2_SB(sb)->s_freeinodes_counter),
percpu_counter_read(&sbi->s_freeclusters_counter));
return percpu_counter_read(fbc);
s64 val = percpu_counter_read(&pl->events);
count = percpu_counter_read(fbc);
dirtied = percpu_counter_read(&wb->stat[WB_DIRTIED]);
written = percpu_counter_read(&wb->stat[WB_WRITTEN]);