Time Complexity and Big-O Notation

I have a homework assignment and its requiring me to compute the time complexity of a code fragment

which equates to

int i = 0;

while(i

int m = n;

while(m > 0){

m = m / 2;

}

i++;

}

from what I have looked up on the internet it is O(n log n), tha could be wrong thought. I would like to know how to the Big O notation given that code

for (i-0;i1) m-m/2