sched: switch sched_features to seqfile
Impact: cleanup
So handling of sched_features read is simplified.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/sched.c b/kernel/sched.c
index 7dd6c86..5419df9 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -703,45 +703,18 @@
#undef SCHED_FEAT
-static int sched_feat_open(struct inode *inode, struct file *filp)
+static int sched_feat_show(struct seq_file *m, void *v)
{
- filp->private_data = inode->i_private;
- return 0;
-}
-
-static ssize_t
-sched_feat_read(struct file *filp, char __user *ubuf,
- size_t cnt, loff_t *ppos)
-{
- char *buf;
- int r = 0;
- int len = 0;
int i;
for (i = 0; sched_feat_names[i]; i++) {
- len += strlen(sched_feat_names[i]);
- len += 4;
+ if (!(sysctl_sched_features & (1UL << i)))
+ seq_puts(m, "NO_");
+ seq_printf(m, "%s ", sched_feat_names[i]);
}
+ seq_puts(m, "\n");
- buf = kmalloc(len + 2, GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
-
- for (i = 0; sched_feat_names[i]; i++) {
- if (sysctl_sched_features & (1UL << i))
- r += sprintf(buf + r, "%s ", sched_feat_names[i]);
- else
- r += sprintf(buf + r, "NO_%s ", sched_feat_names[i]);
- }
-
- r += sprintf(buf + r, "\n");
- WARN_ON(r >= len + 2);
-
- r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
-
- kfree(buf);
-
- return r;
+ return 0;
}
static ssize_t
@@ -786,10 +759,17 @@
return cnt;
}
+static int sched_feat_open(struct inode *inode, struct file *filp)
+{
+ return single_open(filp, sched_feat_show, NULL);
+}
+
static struct file_operations sched_feat_fops = {
- .open = sched_feat_open,
- .read = sched_feat_read,
- .write = sched_feat_write,
+ .open = sched_feat_open,
+ .write = sched_feat_write,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
};
static __init int sched_init_debug(void)