From b7f71899fbdba1cac6773a62ed4ea841b7eda6b0 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Mon, 10 Jun 2019 03:35:41 -0600 Subject: [PATCH] cgroup/bfq: revert bfq.weight symlink change There's some discussion on how to do this the best, and Tejun prefers that BFQ just create the file itself instead of having cgroups support a symlink feature. Hence revert commit 54b7b868e826 and 19e9da9e86c4 for 5.2, and this can be done properly for 5.3. Signed-off-by: Jens Axboe (cherry picked from commit cf8929885de318c0bf73438c9e5dde59d6536f7c) Signed-off-by: Li Yang --- include/linux/cgroup-defs.h | 3 --- kernel/cgroup/cgroup.c | 33 ++++----------------------------- 2 files changed, 4 insertions(+), 32 deletions(-) --- a/include/linux/cgroup-defs.h +++ b/include/linux/cgroup-defs.h @@ -106,8 +106,6 @@ enum { CFTYPE_WORLD_WRITABLE = (1 << 4), /* (DON'T USE FOR NEW FILES) S_IWUGO */ CFTYPE_DEBUG = (1 << 5), /* create when cgroup_debug */ - CFTYPE_SYMLINKED = (1 << 6), /* pointed to by symlink too */ - /* internal flags, do not use outside cgroup core proper */ __CFTYPE_ONLY_ON_DFL = (1 << 16), /* only on default hierarchy */ __CFTYPE_NOT_ON_DFL = (1 << 17), /* not on default hierarchy */ @@ -546,7 +544,6 @@ struct cftype { * end of cftype array. */ char name[MAX_CFTYPE_NAME]; - char link_name[MAX_CFTYPE_NAME]; unsigned long private; /* --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -1465,8 +1465,8 @@ struct cgroup *task_cgroup_from_root(str static struct kernfs_syscall_ops cgroup_kf_syscall_ops; -static char *cgroup_fill_name(struct cgroup *cgrp, const struct cftype *cft, - char *buf, bool write_link_name) +static char *cgroup_file_name(struct cgroup *cgrp, const struct cftype *cft, + char *buf) { struct cgroup_subsys *ss = cft->ss; @@ -1476,26 +1476,13 @@ static char *cgroup_fill_name(struct cgr snprintf(buf, CGROUP_FILE_NAME_MAX, "%s%s.%s", dbg, cgroup_on_dfl(cgrp) ? ss->name : ss->legacy_name, - write_link_name ? cft->link_name : cft->name); + cft->name); } else { - strscpy(buf, write_link_name ? cft->link_name : cft->name, - CGROUP_FILE_NAME_MAX); + strscpy(buf, cft->name, CGROUP_FILE_NAME_MAX); } return buf; } -static char *cgroup_file_name(struct cgroup *cgrp, const struct cftype *cft, - char *buf) -{ - return cgroup_fill_name(cgrp, cft, buf, false); -} - -static char *cgroup_link_name(struct cgroup *cgrp, const struct cftype *cft, - char *buf) -{ - return cgroup_fill_name(cgrp, cft, buf, true); -} - /** * cgroup_file_mode - deduce file mode of a control file * @cft: the control file in question @@ -1654,9 +1641,6 @@ static void cgroup_rm_file(struct cgroup } kernfs_remove_by_name(cgrp->kn, cgroup_file_name(cgrp, cft, name)); - if (cft->flags & CFTYPE_SYMLINKED) - kernfs_remove_by_name(cgrp->kn, - cgroup_link_name(cgrp, cft, name)); } /** @@ -3917,7 +3901,6 @@ static int cgroup_add_file(struct cgroup { char name[CGROUP_FILE_NAME_MAX]; struct kernfs_node *kn; - struct kernfs_node *kn_link; struct lock_class_key *key = NULL; int ret; @@ -3948,14 +3931,6 @@ static int cgroup_add_file(struct cgroup spin_unlock_irq(&cgroup_file_kn_lock); } - if (cft->flags & CFTYPE_SYMLINKED) { - kn_link = kernfs_create_link(cgrp->kn, - cgroup_link_name(cgrp, cft, name), - kn); - if (IS_ERR(kn_link)) - return PTR_ERR(kn_link); - } - return 0; }