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perf trace: Wire up the augmented syscalls with the syscalls:sys_enter_FOO beautifier 

We just check that the evsel is the one we associated with the
bpf-output event associated with the "__augmented_syscalls__" eBPF map,
to show that the formatting is done properly:

  # perf trace -e perf/tools/perf/examples/bpf/augmented_syscalls.c,openat cat /etc/passwd > /dev/null
     0.000 (         ): __augmented_syscalls__:dfd: CWD, filename: 0x43e06da8, flags: CLOEXEC
     0.006 (         ): syscalls:sys_enter_openat:dfd: CWD, filename: 0x43e06da8, flags: CLOEXEC
     0.007 ( 0.004 ms): cat/11486 openat(dfd: CWD, filename: 0x43e06da8, flags: CLOEXEC                 ) = 3
     0.029 (         ): __augmented_syscalls__:dfd: CWD, filename: 0x4400ece0, flags: CLOEXEC
     0.030 (         ): syscalls:sys_enter_openat:dfd: CWD, filename: 0x4400ece0, flags: CLOEXEC
     0.031 ( 0.004 ms): cat/11486 openat(dfd: CWD, filename: 0x4400ece0, flags: CLOEXEC                 ) = 3
     0.249 (         ): __augmented_syscalls__:dfd: CWD, filename: 0xc3700d6
     0.250 (         ): syscalls:sys_enter_openat:dfd: CWD, filename: 0xc3700d6
     0.252 ( 0.003 ms): cat/11486 openat(dfd: CWD, filename: 0xc3700d6                                  ) = 3
  #

Now we just need to get the full blown enter/exit handlers to check if the
evsel being processed is the augmented_syscalls one to go pick the pointer
payloads from the end of the payload.

We also need to state somehow what is the layout for multi pointer arg syscalls.

Also handy would be to have a BTF file with the struct definitions used in
syscalls, compact, generated at kernel built time and available for use in eBPF
programs.

Till we get there we can go on doing some manual coupling of the most relevant
syscalls with some hand built beautifiers.

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-r6ba5izrml82nwfmwcp7jpkm@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
hifive-unleashed-5.1
Arnaldo Carvalho de Melo 2018-08-07 16:26:35 -03:00
parent d3d1c4bdf5
commit 88cf7084f9
1 changed files with 4 additions and 1 deletions
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5
tools/perf/builtin-trace.c
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@ -2042,7 +2042,10 @@ static int trace__event_handler(struct trace *trace, struct perf_evsel *evsel,
fprintf(trace->output, "%s:", evsel->name);
if (perf_evsel__is_bpf_output(evsel)) {
bpf_output__fprintf(trace, sample);
if (evsel == trace->syscalls.events.augmented)
trace__fprintf_sys_enter(trace, evsel, sample);
else
bpf_output__fprintf(trace, sample);
} else if (evsel->tp_format) {
if (strncmp(evsel->tp_format->name, "sys_enter_", 10) ||
trace__fprintf_sys_enter(trace, evsel, sample)) {