E.g.:

  # strace -e futex -p 14437
  strace: Process 14437 attached
  futex(0x7f46f4808d70, FUTEX_WAKE_PRIVATE, 1) = 0
  futex(0x7f46f24e68b0, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 0, {tv_sec=1516636744, tv_nsec=221969000}, 0xffffffff) = -1 ETIMEDOUT (Connection timed out)
 <detached ...>
  #

Should pretty print that 0xffffffff value, like:

  # trace -e futex --tid 14437
     0.028 (   0.005 ms): futex(uaddr: 0x7f46f4808d70, op: WAKE|PRIV, val: 1                    ) = 0
     0.037 (1000.092 ms): futex(uaddr: 0x7f46f24e68b0, op: WAIT_BITSET|PRIV|CLKRT, utime: 0x7f46f23fedf0, val3: MATCH_ANY) = -1 ETIMEDOUT Connection timed out
^C#

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-raef6e352la90600yksthao1@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>