perf tools: Do a few more directory handling optimizations

A few more optimizations for perf when dealing with directories.

Some of them significantly cut down the work which has to be
done. d_type should always be set; otherwise fix the kernel
code. And there are functions available to parse fstab-like
files, so use them.

Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: a.p.zijlstra@chello.nl
Cc: acme@redhat.com
Cc: eranian@google.com
Cc: fweisbec@gmail.com
Cc: lizf@cn.fujitsu.com
Cc: paulus@samba.org
Cc: xiaoguangrong@cn.fujitsu.com
LKML-Reference: <200912192140.nBJLeSfA028905@hs20-bc2-1.build.redhat.com>
[ v2: two small stylistic fixlets ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 6 insertions, 11 deletions

diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c
index 4c06828fe39d..05dc5a735039 100644
--- a/tools/perf/builtin-kmem.c
+++ b/tools/perf/builtin-kmem.c
@@ -92,23 +92,18 @@ static void setup_cpunode_map(void)
         if (!dir1)
                 return;
 
-        while (true) {
-                dent1 = readdir(dir1);
-                if (!dent1)
-                        break;
-
-                if (sscanf(dent1->d_name, "node%u", &mem) < 1)
+        while ((dent1 = readdir(dir1)) != NULL) {
+                if (dent1->d_type != DT_DIR ||
+                    sscanf(dent1->d_name, "node%u", &mem) < 1)
                         continue;
 
                 snprintf(buf, PATH_MAX, "%s/%s", PATH_SYS_NODE, dent1->d_name);
                 dir2 = opendir(buf);
                 if (!dir2)
                         continue;
-                while (true) {
-                        dent2 = readdir(dir2);
-                        if (!dent2)
-                                break;
-                        if (sscanf(dent2->d_name, "cpu%u", &cpu) < 1)
+                while ((dent2 = readdir(dir2)) != NULL) {
+                        if (dent2->d_type != DT_LNK ||
+                            sscanf(dent2->d_name, "cpu%u", &cpu) < 1)
                                 continue;
                         cpunode_map[cpu] = mem;
                 }