Commit cc045e39 authored by Li Zefan's avatar Li Zefan Committed by Tejun Heo
Browse files

cgroup: deal with dummp_top in cgroup_name() and cgroup_path() 



My kernel fails to boot, because blkcg calls cgroup_path() while
cgroupfs is not mounted.

Fix both cgroup_name() and cgroup_path().

Signed-off-by: default avatarLi Zefan <lizefan@huawei.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent 6534fd6c

include/linux/cgroup.h

+10 −2
Original line number Diff line number Diff line
@@ -487,13 +487,21 @@ struct cgroup_subsys_state *seq_css(struct seq_file *seq); 


static inline int cgroup_name(struct cgroup *cgrp, char *buf, size_t buflen)

{

	/* dummy_top doesn't have a kn associated */

	if (cgrp->kn)

		return kernfs_name(cgrp->kn, buf, buflen);

	else

		return strlcpy(buf, "/", buflen);

}



static inline char * __must_check cgroup_path(struct cgroup *cgrp, char *buf,

					      size_t buflen)

{

	/* dummy_top doesn't have a kn associated */

	if (cgrp->kn)

		return kernfs_path(cgrp->kn, buf, buflen);

	strlcpy(buf, "/", buflen);

	return (buflen <= 2) ? NULL : buf;

}



static inline void pr_cont_cgroup_name(struct cgroup *cgrp)