The library calls of a process can be traced with the utility ltrace. The usage is basically similar to that of strace. The option -c returns the count and duration of performed library calls:
$ strace -c find /usr/share/doc % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 86.27 1.071814 30 35327 write 10.15 0.126092 38 3297 getdents64 2.33 0.028931 3 10208 lstat64 0.55 0.006861 2 3122 1 chdir 0.39 0.004890 3 1567 2 open [...] 0.00 0.000003 3 1 uname 0.00 0.000001 1 1 time ------ ----------- ----------- --------- --------- ---------------- 100.00 1.242403 58269 3 total