perf script: Pad DSO name for --call-trace

Pad the DSO name in --call-trace so we don't have the indent screwed by
different DSO name lengths, as now for kernel there's also BPF code
displayed.

  # perf-with-kcore record pt -e intel_pt//ku -- sleep 1
  # perf-core/perf-with-kcore script pt --call-trace

Before:

   sleep 3660 [16] 57036.806464404: ([kernel.kallsyms])                      kretprobe_perf_func
   sleep 3660 [16] 57036.806464404: ([kernel.kallsyms])                          trace_call_bpf
   sleep 3660 [16] 57036.806464404: ([kernel.kallsyms])                              __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806464404: ([kernel.kallsyms])                                  __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806464725: (bpf_prog_da4fe6b3d2c29b25_trace_return)                                         bpf_get_current_pid_tgid
   sleep 3660 [16] 57036.806464725: (bpf_prog_da4fe6b3d2c29b25_trace_return)                                         bpf_ktime_get_ns
   sleep 3660 [16] 57036.806464725: ([kernel.kallsyms])                                          __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806464725: ([kernel.kallsyms])                                              __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806465045: (bpf_prog_da4fe6b3d2c29b25_trace_return)                                         __htab_map_lookup_elem
   sleep 3660 [16] 57036.806465366: ([kernel.kallsyms])                                          memcmp
   sleep 3660 [16] 57036.806465687: (bpf_prog_da4fe6b3d2c29b25_trace_return)                                         bpf_probe_read
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms])                                          probe_kernel_read
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms])                                              __check_object_size
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms])                                                  check_stack_object
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms])                                              copy_user_enhanced_fast_string
   sleep 3660 [16] 57036.806465687: (bpf_prog_da4fe6b3d2c29b25_trace_return)                                         bpf_probe_read
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms])                                          probe_kernel_read
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms])                                              __check_object_size
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms])                                                  check_stack_object
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms])                                              copy_user_enhanced_fast_string
   sleep 3660 [16] 57036.806466008: (bpf_prog_da4fe6b3d2c29b25_trace_return)                                         bpf_get_current_uid_gid
   sleep 3660 [16] 57036.806466008: ([kernel.kallsyms])                                          from_kgid
   sleep 3660 [16] 57036.806466008: ([kernel.kallsyms])                                          from_kuid
   sleep 3660 [16] 57036.806466008: (bpf_prog_da4fe6b3d2c29b25_trace_return)                                         bpf_perf_event_output
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms])                                          perf_event_output
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms])                                              perf_prepare_sample
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms])                                                  perf_misc_flags
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms])                                                      __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms])                                                          __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806466328: ([kvm])                                                      kvm_is_in_guest
   sleep 3660 [16] 57036.806466649: ([kernel.kallsyms])                                                  __perf_event_header__init_id.isra.0
   sleep 3660 [16] 57036.806466649: ([kernel.kallsyms])                                              perf_output_begin

After:

   sleep 3660 [16] 57036.806464404: ([kernel.kallsyms]                      )     kretprobe_perf_func
   sleep 3660 [16] 57036.806464404: ([kernel.kallsyms]                      )         trace_call_bpf
   sleep 3660 [16] 57036.806464404: ([kernel.kallsyms]                      )             __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806464404: ([kernel.kallsyms]                      )                 __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806464725: (bpf_prog_da4fe6b3d2c29b25_trace_return )                     bpf_get_current_pid_tgid
   sleep 3660 [16] 57036.806464725: (bpf_prog_da4fe6b3d2c29b25_trace_return )                     bpf_ktime_get_ns
   sleep 3660 [16] 57036.806464725: ([kernel.kallsyms]                      )                         __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806464725: ([kernel.kallsyms]                      )                             __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806465045: (bpf_prog_da4fe6b3d2c29b25_trace_return )                     __htab_map_lookup_elem
   sleep 3660 [16] 57036.806465366: ([kernel.kallsyms]                      )                         memcmp
   sleep 3660 [16] 57036.806465687: (bpf_prog_da4fe6b3d2c29b25_trace_return )                     bpf_probe_read
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms]                      )                         probe_kernel_read
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms]                      )                             __check_object_size
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms]                      )                                 check_stack_object
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms]                      )                             copy_user_enhanced_fast_string
   sleep 3660 [16] 57036.806465687: (bpf_prog_da4fe6b3d2c29b25_trace_return )                     bpf_probe_read
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms]                      )                         probe_kernel_read
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms]                      )                             __check_object_size
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms]                      )                                 check_stack_object
   sleep 3660 [16] 57036.806465687: ([kernel.kallsyms]                      )                             copy_user_enhanced_fast_string
   sleep 3660 [16] 57036.806466008: (bpf_prog_da4fe6b3d2c29b25_trace_return )                     bpf_get_current_uid_gid
   sleep 3660 [16] 57036.806466008: ([kernel.kallsyms]                      )                         from_kgid
   sleep 3660 [16] 57036.806466008: ([kernel.kallsyms]                      )                         from_kuid
   sleep 3660 [16] 57036.806466008: (bpf_prog_da4fe6b3d2c29b25_trace_return )                     bpf_perf_event_output
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms]                      )                         perf_event_output
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms]                      )                             perf_prepare_sample
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms]                      )                                 perf_misc_flags
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms]                      )                                     __x86_indirect_thunk_rax
   sleep 3660 [16] 57036.806466328: ([kernel.kallsyms]                      )                                         __x86_indirect_thunk_rax

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190508132010.14512-8-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/include/linux/kernel.h

@@ -102,6 +102,7 @@
 
 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args);
 int scnprintf(char * buf, size_t size, const char * fmt, ...);
+int scnprintf_pad(char * buf, size_t size, const char * fmt, ...);
 
 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
 

tools/lib/vsprintf.c

@@ -23,3 +23,22 @@ int scnprintf(char * buf, size_t size, const char * fmt, ...)
 
        return (i >= ssize) ? (ssize - 1) : i;
 }
+
+int scnprintf_pad(char * buf, size_t size, const char * fmt, ...)
+{
+	ssize_t ssize = size;
+	va_list args;
+	int i;
+
+	va_start(args, fmt);
+	i = vscnprintf(buf, size, fmt, args);
+	va_end(args);
+
+	if (i < (int) size) {
+		for (; i < (int) size; i++)
+			buf[i] = ' ';
+		buf[i] = 0x0;
+	}
+
+	return (i >= ssize) ? (ssize - 1) : i;
+}

tools/perf/builtin-script.c

@@ -3297,6 +3297,7 @@ static int parse_call_trace(const struct option *opt __maybe_unused,
 	parse_output_fields(NULL, "-ip,-addr,-event,-period,+callindent", 0);
 	itrace_parse_synth_opts(opt, "cewp", 0);
 	symbol_conf.nanosecs = true;
+	symbol_conf.pad_output_len_dso = 50;
 	return 0;
 }
 

tools/perf/util/map.c

@@ -405,6 +405,7 @@ size_t map__fprintf(struct map *map, FILE *fp)
 
 size_t map__fprintf_dsoname(struct map *map, FILE *fp)
 {
+	char buf[symbol_conf.pad_output_len_dso + 1];
 	const char *dsoname = "[unknown]";
 
 	if (map && map->dso) {
@@ -414,6 +415,11 @@ size_t map__fprintf_dsoname(struct map *map, FILE *fp)
 			dsoname = map->dso->name;
 	}
 
+	if (symbol_conf.pad_output_len_dso) {
+		scnprintf_pad(buf, symbol_conf.pad_output_len_dso, "%s", dsoname);
+		dsoname = buf;
+	}
+
 	return fprintf(fp, "%s", dsoname);
 }
 

tools/perf/util/symbol_conf.h

@@ -69,6 +69,7 @@ struct symbol_conf {
 			*tid_list;
 	const char	*symfs;
 	int		res_sample;
+	int		pad_output_len_dso;
 };
 
 extern struct symbol_conf symbol_conf;