Merge pull request snabbco#195 from kbara/fixgetcpu

Fix getcpu: the cpu argument was incorrectly given the node variable

syscall/linux/c.lua

@@ -685,7 +685,7 @@ C.gettimeofday = ffi.C.gettimeofday
 --function C.gettimeofday(tv, tz) return syscall(sys.gettimeofday, void(tv), void(tz)) end
 
 -- glibc does not provide getcpu; it is however VDSO
-function C.getcpu(cpu, node, tcache) return syscall(sys.getcpu, void(node), void(node), void(tcache)) end
+function C.getcpu(cpu, node, tcache) return syscall(sys.getcpu, void(cpu), void(node), void(tcache)) end
 -- time is VDSO but not really performance critical; does not exist for some architectures
 if sys.time then
   function C.time(t) return syscall(sys.time, void(t)) end