who called mmap?

gistfile1.txt

$ sudo perf probe -x /nix/store/3wa1xwnfv8ada1za1r8m4vmsiz1jifqq-glibc-2.32-35/lib/libc.so.6 '--add=mmap%return $retval'
Added new event:
  probe_libc:mmap__return (on mmap%return in /nix/store/3wa1xwnfv8ada1za1r8m4vmsiz1jifqq-glibc-2.32-35/lib/libc-2.32.so with $retval)

You can now use it in all perf tools, such as:

	perf record -e probe_libc:mmap__return -aR sleep 1

$ sudo perf record  -e probe_libc:mmap__return -g -aR `which ghc` -e 'putStrLn "hej"'

$ sudo perf script
ghc 1196781 [001] 320274.285711: probe_libc:mmap__return: (7fab15bcd400 <- 7fab15b0aad4) arg1=0x7fab15915000
            7fab15b0aad4 _nl_load_locale_from_archive+0x4d4 (/nix/store/3wa1xwnfv8ada1za1r8m4vmsiz1jifqq-glibc-2.32-35/lib/libc-2.32.so)
            7fab15b098e4 _nl_find_locale+0xe4 (/nix/store/3wa1xwnfv8ada1za1r8m4vmsiz1jifqq-glibc-2.32-35/lib/libc-2.32.so)
            7fab15b092cb setlocale+0x18b (/nix/store/3wa1xwnfv8ada1za1r8m4vmsiz1jifqq-glibc-2.32-35/lib/libc-2.32.so)
                  4ae9b7 [unknown] ([unknown])
        fc8e40fffc8e40ff [unknown] ([unknown])
...

# arg1 is the return value