[PATCH 4/4] perf annotate: Introduce source_code to collect actual code

[Taeung Song]

The output of perf-annotate has a problem.
It is so confusing that the output is mixed with
both source code and assembly code.
IMHO, we need readable annotate view based on source code,
not mixed view. (not depending on 'objdump -S')

And to do that, we can collect actual source code per function(sym)
using addr2line() and we can handle 'struct source_code'
that contains each line of code.

In near future, it would be used for new annotate view based on
actual source code per function(sym).

Cc: Namhyung Kim <namhy...@kernel.org>
Cc: Jiri Olsa <jo...@redhat.com>
Signed-off-by: Taeung Song <treeze.tae...@gmail.com>
---
 tools/perf/util/annotate.c | 117 +++++++++++++++++++++++++++++++++++++++++++++
 tools/perf/util/annotate.h |   7 +++
 2 files changed, 124 insertions(+)

diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
index acd500b..93abc1e 100644
--- a/tools/perf/util/annotate.c
+++ b/tools/perf/util/annotate.c
@@ -1590,6 +1590,116 @@ static void symbol__free_source_line(struct symbol 
*sym, int len)
        zfree(&notes->src->lines);
 }
 
+static int symbol__free_source_code(struct symbol *sym)
+{
+       struct annotation *notes = symbol__annotation(sym);
+       struct source_code *pos, *tmp;
+
+       if (&notes->src->code == NULL)
+               return -1;
+
+       list_for_each_entry_safe(pos, tmp, &notes->src->code, node) {
+               list_del(&pos->node);
+               zfree(&pos->code_line);
+               free(pos);
+       }
+       return 0;
+}
+
+static int parse_srcline(char *srcline, char **path, int *line_nr)
+{
+       char *sep;
+
+       if (!strcmp(srcline, SRCLINE_UNKNOWN))
+               return -1;
+
+       sep = strchr(srcline, ':');
+       if (sep) {
+               *sep = '\0';
+               *path = srcline;
+               *line_nr = strtoul(++sep, NULL, 0);
+       } else
+               return -1;
+
+       return 0;
+}
+
+static bool symbol__get_source_code(struct symbol *sym, struct map *map)
+{
+       FILE *file;
+       int first_linenr, start_linenr, end_linenr;
+       size_t len;
+       char *line = NULL, *path, *start_srcline, *end_srcline;
+       u64 start = map__rip_2objdump(map, sym->start);
+       u64 end = map__rip_2objdump(map, sym->end - 1);
+       bool bef_fullpath = srcline_full_filename;
+       bool ret = false;
+       struct annotation *notes = symbol__annotation(sym);
+
+       srcline_full_filename = true;
+       start_srcline = get_srcline(map->dso, start, NULL, false);
+       end_srcline = get_srcline(map->dso, end, NULL, false);
+       srcline_full_filename = bef_fullpath;
+
+       if (parse_srcline(start_srcline, &path, &start_linenr) < 0)
+               return false;
+       if (parse_srcline(end_srcline, &path, &end_linenr) < 0)
+               return false;
+
+       /* To read a function header for the sym */
+       if (start_linenr > 4)
+               first_linenr = start_linenr - 4;
+       else
+               first_linenr = 1;
+
+       if (access(path, R_OK) != 0)
+               return false;
+
+       file = fopen(path, "r");
+       if (!file)
+               return false;
+
+       INIT_LIST_HEAD(&notes->src->code);
+
+       while (!feof(file)) {
+               int nr;
+               char *c, *parsed_line;
+               struct source_code *code;
+
+               if (getline(&line, &len, file) < 0) {
+                       symbol__free_source_code(sym);
+                       break;
+               }
+
+               if (++nr < first_linenr)
+                       continue;
+
+               parsed_line = rtrim(line);
+               c = strchr(parsed_line, '\n');
+               if (c)
+                       *c = '\0';
+               code = zalloc(sizeof(*code));
+               if (!code) {
+                       symbol__free_source_code(sym);
+                       break;
+               }
+               code->nr = nr;
+               code->code_line = strdup(parsed_line);
+               list_add_tail(&code->node, &notes->src->code);
+
+               if (nr == end_linenr) {
+                       ret = true;
+                       break;
+               }
+       }
+
+       free(line);
+       fclose(file);
+       free_srcline(start_srcline);
+       free_srcline(end_srcline);
+       return ret;
+}
+
 /* Get the filename:line for the colored entries */
 static int symbol__get_source_line(struct symbol *sym, struct map *map,
                                   struct perf_evsel *evsel,
@@ -1862,6 +1972,7 @@ int symbol__tty_annotate(struct symbol *sym, struct map 
*map,
        struct dso *dso = map->dso;
        struct rb_root source_line = RB_ROOT;
        u64 len;
+       bool has_code = false;
 
        if (symbol__disassemble(sym, map, perf_evsel__env_arch(evsel), 0) < 0)
                return -1;
@@ -1874,11 +1985,17 @@ int symbol__tty_annotate(struct symbol *sym, struct map 
*map,
                print_summary(&source_line, dso->long_name);
        }
 
+       if (symbol_conf.annotate_src)
+               has_code = symbol__get_source_code(sym, map);
+
        symbol__annotate_printf(sym, map, evsel, full_paths,
                                min_pcnt, max_lines, 0);
        if (print_lines)
                symbol__free_source_line(sym, len);
 
+       if (has_code)
+               symbol__free_source_code(sym);
+
        disasm__purge(&symbol__annotation(sym)->src->source);
 
        return 0;
diff --git a/tools/perf/util/annotate.h b/tools/perf/util/annotate.h
index 09776b5..7231f46 100644
--- a/tools/perf/util/annotate.h
+++ b/tools/perf/util/annotate.h
@@ -95,6 +95,12 @@ struct cyc_hist {
        u16     reset;
 };
 
+struct source_code {
+       struct list_head node;
+       int nr;
+       char *code_line;
+};
+
 struct source_line_samples {
        double          percent;
        double          percent_sum;
@@ -123,6 +129,7 @@ struct source_line {
  */
 struct annotated_source {
        struct list_head   source;
+       struct list_head   code;
        struct source_line *lines;
        int                nr_histograms;
        size_t             sizeof_sym_hist;
-- 
2.7.4