perf report: Fix kernel symbol resolution

kallsyms have just the symbol start, so we need to read two lines
to get the len.

[ Impact: fix incorrect kernel symbol display in perf report ]

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/Documentation/perf_counter/builtin-report.c b/Documentation/perf_counter/builtin-report.c
index 697f960495fc831d8ec3ab71f2dd455630c1e9bc..b19b893d4ff5da24adc99a12c4adbea5ed8c620b 100644 (file)
--- a/Documentation/perf_counter/builtin-report.c
+++ b/Documentation/perf_counter/builtin-report.c
@@ -360,9 +360,17 @@ 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 c, symbf[4096];
+               char symbf[4096];
 
                if (getline(&line, &n, file) < 0)
                        break;
@@ -371,12 +379,18 @@ static int load_kallsyms(void)
                        goto out_delete_dso;
 
                if (sscanf(line, "%llx %c %s", &start, &c, symbf) == 3) {
-                       struct symbol *sym = symbol__new(start, 0x1000000, symbf);
+                       if (start > previous_start) {
+                               struct symbol *sym = symbol__new(previous_start,
+                                                                start - previous_start,
+                                                                previous_symbf);
 
-                       if (sym == NULL)
-                               goto out_delete_dso;
+                               if (sym == NULL)
+                                       goto out_delete_dso;
 
-                       dso__insert_symbol(kernel_dso, sym);
+                               dso__insert_symbol(kernel_dso, sym);
+                               previous_start = start;
+                               strcpy(previous_symbf, symbf);
+                       }
                }
        }
 
@@ -385,6 +399,8 @@ static int load_kallsyms(void)
        fclose(file);
        return 0;
 
+out_delete_line:
+       free(line);
 out_delete_dso:
        dso__delete(kernel_dso);
        return -1;