perf tools: Make CPUINFO_PROC an array to support different kernel versions

After kernel 3.7 (commit b4b8f770eb10a1bccaf8aa0ec1956e2dd7ed1e0a),
/proc/cpuinfo replaces 'Processor' to 'model name'.

This patch makes CPUINFO_PROC to an array and provides two choices for
ARM, makes it compatible for different kernel version.

v1 -> v2: minor changes as suggested by Namhyung Kim:

 - Doesn't pass @h and @evlist to __write_cpudesc;
 - Coding style fix.

v2 -> v3:
  - Rebase:
    git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git perf/core

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1414115126-7479-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index ce0de00..26f5b2f 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -579,16 +579,12 @@
 	return do_write_string(fd, perf_version_string);
 }
 
-static int write_cpudesc(int fd, struct perf_header *h __maybe_unused,
-		       struct perf_evlist *evlist __maybe_unused)
+static int __write_cpudesc(int fd, const char *cpuinfo_proc)
 {
-#ifndef CPUINFO_PROC
-#define CPUINFO_PROC NULL
-#endif
 	FILE *file;
 	char *buf = NULL;
 	char *s, *p;
-	const char *search = CPUINFO_PROC;
+	const char *search = cpuinfo_proc;
 	size_t len = 0;
 	int ret = -1;
 
@@ -638,6 +634,25 @@
 	return ret;
 }
 
+static int write_cpudesc(int fd, struct perf_header *h __maybe_unused,
+		       struct perf_evlist *evlist __maybe_unused)
+{
+#ifndef CPUINFO_PROC
+#define CPUINFO_PROC {"model name", }
+#endif
+	const char *cpuinfo_procs[] = CPUINFO_PROC;
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(cpuinfo_procs); i++) {
+		int ret;
+		ret = __write_cpudesc(fd, cpuinfo_procs[i]);
+		if (ret >= 0)
+			return ret;
+	}
+	return -1;
+}
+
+
 static int write_nrcpus(int fd, struct perf_header *h __maybe_unused,
 			struct perf_evlist *evlist __maybe_unused)
 {