perf kvm: Use strerror_r instead of strerror

Use strerror_r instead of strerror in error messages for thread-safety.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20140814022251.3545.83718.stgit@kbuild-fedora.novalocalSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-kvm.c

@@ -990,6 +990,7 @@ static int kvm_live_open_events(struct perf_kvm_stat *kvm)
 	int err, rc = -1;
 	struct perf_evsel *pos;
 	struct perf_evlist *evlist = kvm->evlist;
+	char sbuf[STRERR_BUFSIZE];
 
 	perf_evlist__config(evlist, &kvm->opts);
 
@@ -1026,12 +1027,14 @@ static int kvm_live_open_events(struct perf_kvm_stat *kvm)
 
 	err = perf_evlist__open(evlist);
 	if (err < 0) {
-		printf("Couldn't create the events: %s\n", strerror(errno));
+		printf("Couldn't create the events: %s\n",
+		       strerror_r(errno, sbuf, sizeof(sbuf)));
 		goto out;
 	}
 
 	if (perf_evlist__mmap(evlist, kvm->opts.mmap_pages, false) < 0) {
-		ui__error("Failed to mmap the events: %s\n", strerror(errno));
+		ui__error("Failed to mmap the events: %s\n",
+			  strerror_r(errno, sbuf, sizeof(sbuf)));
 		perf_evlist__close(evlist);
 		goto out;
 	}