forked from luck/tmp_suning_uos_patched
df820f8de4
Overlayfs is using clone_private_mount() to create internal mounts for underlying layers. These are used for operations requiring a path, such as dentry_open(). Since these private mounts are not in any namespace they are treated as short term, "detached" mounts and mntput() involves taking the global mount_lock, which can result in serious cacheline pingpong. Make these private mounts longterm instead, which trade the penalty on mntput() for a slightly longer shutdown time due to an added RCU grace period when putting these mounts. Introduce a new helper kern_unmount_many() that can take care of multiple longterm mounts with a single RCU grace period. Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> |
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copy_up.c | ||
dir.c | ||
export.c | ||
file.c | ||
inode.c | ||
Kconfig | ||
Makefile | ||
namei.c | ||
overlayfs.h | ||
ovl_entry.h | ||
readdir.c | ||
super.c | ||
util.c |