cgroup: use kzalloc() instead of kmalloc()
There's no point in using kmalloc() instead of the clearing variant
for trivial stuff. We can live dangerously elsewhere. Use kzalloc()
instead and drop 0 inits.
While at it, do trivial code reorganization in cgroup_file_open().
This patch doesn't introduce any functional changes.
v2: I was caught in the very distant past where list_del() didn't
poison and the initial version converted list_del()s to
list_del_init()s too. Li and Kent took me out of the stasis
chamber.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kent Overstreet <koverstreet@google.com>
Acked-by: Li Zefan <lizefan@huawei.com>
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index ef97bd0..d86a847 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -597,7 +597,7 @@
INIT_LIST_HEAD(tmp_links);
for (i = 0; i < count; i++) {
- link = kmalloc(sizeof(*link), GFP_KERNEL);
+ link = kzalloc(sizeof(*link), GFP_KERNEL);
if (!link) {
free_cgrp_cset_links(tmp_links);
return -ENOMEM;
@@ -658,7 +658,7 @@
if (cset)
return cset;
- cset = kmalloc(sizeof(*cset), GFP_KERNEL);
+ cset = kzalloc(sizeof(*cset), GFP_KERNEL);
if (!cset)
return NULL;
@@ -2475,10 +2475,12 @@
cft = __d_cft(file->f_dentry);
if (cft->read_map || cft->read_seq_string) {
- struct cgroup_seqfile_state *state =
- kzalloc(sizeof(*state), GFP_USER);
+ struct cgroup_seqfile_state *state;
+
+ state = kzalloc(sizeof(*state), GFP_USER);
if (!state)
return -ENOMEM;
+
state->cft = cft;
state->cgroup = __d_cgrp(file->f_dentry->d_parent);
file->f_op = &cgroup_seqfile_operations;
@@ -3511,7 +3513,7 @@
}
}
/* entry not found; create a new one */
- l = kmalloc(sizeof(struct cgroup_pidlist), GFP_KERNEL);
+ l = kzalloc(sizeof(struct cgroup_pidlist), GFP_KERNEL);
if (!l) {
mutex_unlock(&cgrp->pidlist_mutex);
return l;
@@ -3520,8 +3522,6 @@
down_write(&l->mutex);
l->key.type = type;
l->key.ns = get_pid_ns(ns);
- l->use_count = 0; /* don't increment here */
- l->list = NULL;
l->owner = cgrp;
list_add(&l->links, &cgrp->pidlists);
mutex_unlock(&cgrp->pidlist_mutex);
