perf kvm: Move code to generate filename for perf-kvm to function.

The code in builtin-kvm.c to generate filename for perf-kvm is useful to
other command such as builtin-diff.

This patch move the related code form builtin-kvm.c to util/util.c and
wrap them in a function named get_filename_for_perf_kvm.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Link: http://lkml.kernel.org/r/5e09a5c47e8a495e888cbdc65a6fafb2c950f529.1386368672.git.yangds.fnst@cn.fujitsu.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

3 files changed, 17 insertions, 6 deletions

diff --git a/tools/perf/builtin-kvm.c b/tools/perf/builtin-kvm.c
index c2e5d56a291d..c6fa3cbd45a9 100644
--- a/tools/perf/builtin-kvm.c
+++ b/tools/perf/builtin-kvm.c
@@ -1713,12 +1713,7 @@ int cmd_kvm(int argc, const char **argv, const char *prefix __maybe_unused)
                 perf_guest = 1;
 
         if (!file_name) {
-                if (perf_host && !perf_guest)
-                        file_name = strdup("perf.data.host");
-                else if (!perf_host && perf_guest)
-                        file_name = strdup("perf.data.guest");
-                else
-                        file_name = strdup("perf.data.kvm");
+                file_name = get_filename_for_perf_kvm();
 
                 if (!file_name) {
                         pr_err("Failed to allocate memory for filename\n");
diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c
index bae8756a4eb1..4a57609c0b43 100644
--- a/tools/perf/util/util.c
+++ b/tools/perf/util/util.c
@@ -482,3 +482,17 @@ int filename__read_str(const char *filename, char **buf, size_t *sizep)
         close(fd);
         return err;
 }
+
+const char *get_filename_for_perf_kvm(void)
+{
+        const char *filename;
+
+        if (perf_host && !perf_guest)
+                filename = strdup("perf.data.host");
+        else if (!perf_host && perf_guest)
+                filename = strdup("perf.data.guest");
+        else
+                filename = strdup("perf.data.kvm");
+
+        return filename;
+}
diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index 659abf30e01b..0171213d1d4d 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -321,4 +321,6 @@ void free_srcline(char *srcline);
 
 int filename__read_int(const char *filename, int *value);
 int filename__read_str(const char *filename, char **buf, size_t *sizep);
+
+const char *get_filename_for_perf_kvm(void);
 #endif /* GIT_COMPAT_UTIL_H */