Commit 1cdf618f authored Aug 21, 2018 by Arnaldo Carvalho de Melo

perf trace: Print the syscall name for augmented_syscalls

Since we copy all the payload for raw_syscalls:sys_enter plus add
expanded pointers, we can use the syscall id to get its name, etc:

  # grep 'field:.* id' /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/format
	field:long id;	offset:8;	size:8;	signed:1;
  #

Before:

  # perf trace -e tools/perf/examples/bpf/augmented_syscalls.c,openat cat /etc/passwd > /dev/null
     0.000 (         ): __augmented_syscalls__:dfd: CWD, filename: 0xec9f9da8, flags: CLOEXEC
     0.006 ( 0.006 ms): cat/2395 openat(dfd: CWD, filename: 0xec9f9da8, flags: CLOEXEC) = 3
     0.041 (         ): __augmented_syscalls__:dfd: CWD, filename: 0xecc01ce0, flags: CLOEXEC
     0.042 ( 0.007 ms): cat/2395 openat(dfd: CWD, filename: 0xecc01ce0, flags: CLOEXEC) = 3
     0.376 (         ): __augmented_syscalls__:dfd: CWD, filename: 0xac0a806b
     0.379 ( 0.006 ms): cat/2395 openat(dfd: CWD, filename: 0xac0a806b) = 3
  #

After:

  # perf trace -e tools/perf/examples/bpf/augmented_syscalls.c,openat cat /etc/passwd > /dev/null
     0.000 (         ): openat(dfd: CWD, filename: 0x31b6dda8, flags: CLOEXEC)
     0.009 ( 0.009 ms): cat/3619 openat(dfd: CWD, filename: 0x31b6dda8, flags: CLOEXEC) = 3
     0.051 (         ): openat(dfd: CWD, filename: 0x31d75ce0, flags: CLOEXEC)
     0.054 ( 0.010 ms): cat/3619 openat(dfd: CWD, filename: 0x31d75ce0, flags: CLOEXEC) = 3
     0.539 (         ): openat(dfd: CWD, filename: 0xca71506b)
     0.543 ( 0.115 ms): cat/3619 openat(dfd: CWD, filename: 0xca71506b) = 3
  #

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-epz6y9i0eavmerc5ha98t7gn@git.kernel.org


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

parent 6ccc18a9

tools/perf/builtin-trace.c

+25 −4

Original line number	Diff line number	Diff line
		@@ -2055,12 +2055,32 @@ static int trace__event_handler(struct trace trace, struct perf_evsel evsel,
		if (trace->trace_syscalls)
		fprintf(trace->output, "( ): ");

		if (evsel == trace->syscalls.events.augmented) {
		int id = perf_evsel__sc_tp_uint(evsel, id, sample);
		struct syscall *sc = trace__syscall_info(trace, evsel, id);

		if (sc) {
		struct thread *thread = machine__findnew_thread(trace->host, sample->pid, sample->tid);

		if (thread) {
		fprintf(trace->output, "%s(", sc->name);
		trace__fprintf_sys_enter(trace, evsel, sample);
		fputc(')', trace->output);
		thread__put(thread);
		goto newline;
		}
		}

		/*
		* XXX: Not having the associated syscall info or not finding/adding
		* the thread should never happen, but if it does...
		* fall thru and print it as a bpf_output event.
		*/
		}

		fprintf(trace->output, "%s:", evsel->name);

		if (perf_evsel__is_bpf_output(evsel)) {
		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) \|\|
		@@ -2071,6 +2091,7 @@ static int trace__event_handler(struct trace trace, struct perf_evsel evsel,
		}
		}

		newline:
		fprintf(trace->output, "\n");

		if (callchain_ret > 0)

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