From: Ran Xiaokai <ran.xiaokai@xxxxxxxxxx>
All tmpfs and ramfs pages have PG_dirty bit set
once they are allocated and added to the pagecache。So pages
can not be freed from tmpfs or ramfs. So skip tmpfs and ramfs
when drop caches.
Signed-off-by: Ran Xiaokai <ran.xiaokai@xxxxxxxxxx>
---
fs/drop_caches.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/fs/drop_caches.c b/fs/drop_caches.c
index e619c31b6bd9..600c043c1eb7 100644
--- a/fs/drop_caches.c
+++ b/fs/drop_caches.c
@@ -10,6 +10,7 @@
#include <linux/writeback.h>
#include <linux/sysctl.h>
#include <linux/gfp.h>
+#include <linux/magic.h>
#include "internal.h"
/* A global variable is a bit ugly, but it keeps the code simple */
@@ -19,6 +20,9 @@ static void drop_pagecache_sb(struct super_block *sb, void *unused)
{
struct inode *inode, *toput_inode = NULL;
+ if (sb->s_magic == TMPFS_MAGIC || sb->s_magic == RAMFS_MAGIC)
+ return;
+
spin_lock(&sb->s_inode_list_lock);
list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
spin_lock(&inode->i_lock);
--
2.15.2
