[PATCH 1/1 tip] perf: Don't assume /proc/kallsyms is ordered

Arnaldo Carvalho de Melo
2009-05-26T15:22:20Z

Please fix the previous fix with this:

commit 64d254523be740b224533e0e4982cda7f25c0348
Author: Arnaldo Carvalho de Melo <acme@redhat.com>
Date: Tue May 26 12:08:10 2009 -0300

perf: Don't assume /proc/kallsyms is ordered

Since we _are_ ordering it by the symbol start, just traverse the
freshly built rbtree setting the prev->end members to curr->start - 1.

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

diff --git a/Documentation/perf_counter/builtin-report.c b/Documentation/perf_counter/builtin-report.c
index b19b893..5a385e8 100644
--- a/Documentation/perf_counter/builtin-report.c
+++ b/Documentation/perf_counter/builtin-report.c
@@ -360,17 +360,9 @@ static int load_kallsyms(void)
char *line = NULL;
size_t n;

- if (getline(&line, &n, file) < 0 || !line)
- goto out_delete_dso;
-
- unsigned long long previous_start;
- char c, previous_symbf[4096];
- if (sscanf(line, "%llx %c %s", &previous_start, &c, previous_symbf) != 3)
- goto out_delete_line;
-
while (!feof(file)) {
unsigned long long start;
- char symbf[4096];
+ char c, symbf[4096];

if (getline(&line, &n, file) < 0)
break;
@@ -379,21 +371,35 @@ static int load_kallsyms(void)
goto out_delete_dso;

if (sscanf(line, "%llx %c %s", &start, &c, symbf) == 3) {
- if (start > previous_start) {
- struct symbol *sym = symbol__new(previous_start,
- start - previous_start,
- previous_symbf);
+ /*
+ * Well fix up the end later, when we have all sorted.
+ */
+ struct symbol *sym = symbol__new(start, 0xdead, symbf);

- if (sym == NULL)
- goto out_delete_dso;
+ if (sym == NULL)
+ goto out_delete_dso;

- dso__insert_symbol(kernel_dso, sym);
- previous_start = start;
- strcpy(previous_symbf, symbf);
- }
+ dso__insert_symbol(kernel_dso, sym);
}
}

+ /*
+ * Now that we have all sorted out, just set the ->end of all
+ * symbols
+ */
+ struct rb_node *nd, *prevnd = rb_first(&kernel_dso->syms);
+
+ if (prevnd == NULL)
+ goto out_delete_line;
+
+ for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
+ struct symbol *prev = rb_entry(prevnd, struct symbol, rb_node),
+ *curr = rb_entry(nd, struct symbol, rb_node);
+
+ prev->end = curr->start - 1;
+ prevnd = nd;
+ }
+
dsos__add(kernel_dso);
free(line);
fclose(file);