• Kaixu Xia's avatar
    bpf: fix build warnings and add function read_trace_pipe() · 5ed3ccbd
    Kaixu Xia authored
    There are two improvements in this patch:
     1. Fix the build warnings;
     2. Add function read_trace_pipe() to print the result on
        the screen;
    
    Before this patch, we can get the result through /sys/kernel/de
    bug/tracing/trace_pipe and get nothing on the screen.
    By applying this patch, the result can be printed on the screen.
      $ ./tracex6
    	...
             tracex6-705   [003] d..1   131.428593: : CPU-3   19981414
                sshd-683   [000] d..1   131.428727: : CPU-0   221682321
                sshd-683   [000] d..1   131.428821: : CPU-0   221808766
                sshd-683   [000] d..1   131.428950: : CPU-0   221982984
                sshd-683   [000] d..1   131.429045: : CPU-0   222111851
             tracex6-705   [003] d..1   131.429168: : CPU-3   20757551
                sshd-683   [000] d..1   131.429170: : CPU-0   222281240
                sshd-683   [000] d..1   131.429261: : CPU-0   222403340
                sshd-683   [000] d..1   131.429378: : CPU-0   222561024
    	...
    Signed-off-by: default avatarKaixu Xia <xiakaixu@huawei.com>
    Acked-by: default avatarAlexei Starovoitov <ast@plumgrid.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    5ed3ccbd