perf_counter: tool: handle 0-length data files

Avoid perf-report barfing on 0-length data files.

[ Impact: fix perf-report SIGBUS ]

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
LKML-Reference: <20090501102533.196245693@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/Documentation/perf_counter/perf-report.cc b/Documentation/perf_counter/perf-report.cc
index 933a075..911d7f3 100644 (file)
--- a/Documentation/perf_counter/perf-report.cc
+++ b/Documentation/perf_counter/perf-report.cc
@@ -402,6 +402,11 @@ int main(int argc, char *argv[])
                exit(-1);
        }
 
+       if (!stat.st_size) {
+               fprintf(stderr, "zero-sized file, nothing to do!\n");
+               exit(0);
+       }
+
        load_kallsyms();
 
 remap: