perf record -g -t tid perf report -g fractal,0.2,caller perf report -g fractal,0.2,callee http://blog.csdn.net/zhangskd/article/details/37902159
perf record -g -p pid perf record -g -t tid perf report -g fractal,0.2,caller perf report -g fractal,0.2,callee