[PATCH 2/3] mm: vmstat: Convert to use DEFINE_SEQ_ATTRIBUTE macro

[Kefeng Wang]

Use DEFINE_SEQ_ATTRIBUTE macro to simplify the code.

Signed-off-by: Kefeng Wang <wangkefeng.w...@huawei.com>
---
 mm/vmstat.c | 32 ++++++--------------------------
 1 file changed, 6 insertions(+), 26 deletions(-)

diff --git a/mm/vmstat.c b/mm/vmstat.c
index 7f2e87cb7049..35219271796f 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -2055,24 +2055,14 @@ static int unusable_show(struct seq_file *m, void *arg)
        return 0;
 }
 
-static const struct seq_operations unusable_op = {
+static const struct seq_operations unusable_sops = {
        .start  = frag_start,
        .next   = frag_next,
        .stop   = frag_stop,
        .show   = unusable_show,
 };
 
-static int unusable_open(struct inode *inode, struct file *file)
-{
-       return seq_open(file, &unusable_op);
-}
-
-static const struct file_operations unusable_file_ops = {
-       .open           = unusable_open,
-       .read           = seq_read,
-       .llseek         = seq_lseek,
-       .release        = seq_release,
-};
+DEFINE_SEQ_ATTRIBUTE(unusable);
 
 static void extfrag_show_print(struct seq_file *m,
                                        pg_data_t *pgdat, struct zone *zone)
@@ -2107,24 +2097,14 @@ static int extfrag_show(struct seq_file *m, void *arg)
        return 0;
 }
 
-static const struct seq_operations extfrag_op = {
+static const struct seq_operations extfrag_sops = {
        .start  = frag_start,
        .next   = frag_next,
        .stop   = frag_stop,
        .show   = extfrag_show,
 };
 
-static int extfrag_open(struct inode *inode, struct file *file)
-{
-       return seq_open(file, &extfrag_op);
-}
-
-static const struct file_operations extfrag_file_ops = {
-       .open           = extfrag_open,
-       .read           = seq_read,
-       .llseek         = seq_lseek,
-       .release        = seq_release,
-};
+DEFINE_SEQ_ATTRIBUTE(extfrag);
 
 static int __init extfrag_debug_init(void)
 {
@@ -2133,10 +2113,10 @@ static int __init extfrag_debug_init(void)
        extfrag_debug_root = debugfs_create_dir("extfrag", NULL);
 
        debugfs_create_file("unusable_index", 0444, extfrag_debug_root, NULL,
-                           &unusable_file_ops);
+                           &unusable_fops);
 
        debugfs_create_file("extfrag_index", 0444, extfrag_debug_root, NULL,
-                           &extfrag_file_ops);
+                           &extfrag_fops);
 
        return 0;
 }
-- 
2.26.2