[PATCH 03/77] perf trace: Print the syscall name for augmented_syscalls

[Arnaldo Carvalho de Melo]

From: Arnaldo Carvalho de Melo <a...@redhat.com>

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.hun...@intel.com>
Cc: David Ahern <dsah...@gmail.com>
Cc: Jiri Olsa <jo...@kernel.org>
Cc: Namhyung Kim <namhy...@kernel.org>
Cc: Wang Nan <wangn...@huawei.com>
Link: https://lkml.kernel.org/n/tip-epz6y9i0eavmerc5ha98t...@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com>
---
 tools/perf/builtin-trace.c | 29 +++++++++++++++++++++++++----
 1 file changed, 25 insertions(+), 4 deletions(-)

diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 7deae6c8cb25..bcf882afd6d0 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -2055,13 +2055,33 @@ 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);
+               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)) {
@@ -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)
-- 
2.14.4