@@ -65,6 +65,23 @@ static inline struct cgroup_fs_context *
return container_of(kfc, struct cgroup_fs_context, kfc);
}
+struct cgroup_pidlist;
+
+struct cgroup_file_ctx {
+ struct {
+ void *trigger;
+ } psi;
+
+ struct {
+ bool started;
+ struct css_task_iter iter;
+ } procs;
+
+ struct {
+ struct cgroup_pidlist *pidlist;
+ } procs1;
+};
+
/*
* A cgroup can be associated with multiple css_sets as different tasks may
* belong to different cgroups on different hierarchies. In the other
@@ -398,6 +398,7 @@ static void *cgroup_pidlist_start(struct
* next pid to display, if any
*/
struct kernfs_open_file *of = s->private;
+ struct cgroup_file_ctx *ctx = of->priv;
struct cgroup *cgrp = seq_css(s)->cgroup;
struct cgroup_pidlist *l;
enum cgroup_filetype type = seq_cft(s)->private;
@@ -407,25 +408,24 @@ static void *cgroup_pidlist_start(struct
mutex_lock(&cgrp->pidlist_mutex);
/*
- * !NULL @of->priv indicates that this isn't the first start()
- * after open. If the matching pidlist is around, we can use that.
- * Look for it. Note that @of->priv can't be used directly. It
- * could already have been destroyed.
+ * !NULL @ctx->procs1.pidlist indicates that this isn't the first
+ * start() after open. If the matching pidlist is around, we can use
+ * that. Look for it. Note that @ctx->procs1.pidlist can't be used
+ * directly. It could already have been destroyed.
*/
- if (of->priv)
- of->priv = cgroup_pidlist_find(cgrp, type);
+ if (ctx->procs1.pidlist)
+ ctx->procs1.pidlist = cgroup_pidlist_find(cgrp, type);
/*
* Either this is the first start() after open or the matching
* pidlist has been destroyed inbetween. Create a new one.
*/
- if (!of->priv) {
- ret = pidlist_array_load(cgrp, type,
- (struct cgroup_pidlist **)&of->priv);
+ if (!ctx->procs1.pidlist) {
+ ret = pidlist_array_load(cgrp, type, &ctx->procs1.pidlist);
if (ret)
return ERR_PTR(ret);
}
- l = of->priv;
+ l = ctx->procs1.pidlist;
if (pid) {
int end = l->length;
@@ -453,7 +453,8 @@ static void *cgroup_pidlist_start(struct
static void cgroup_pidlist_stop(struct seq_file *s, void *v)
{
struct kernfs_open_file *of = s->private;
- struct cgroup_pidlist *l = of->priv;
+ struct cgroup_file_ctx *ctx = of->priv;
+ struct cgroup_pidlist *l = ctx->procs1.pidlist;
if (l)
mod_delayed_work(cgroup_pidlist_destroy_wq, &l->destroy_dwork,
@@ -464,7 +465,8 @@ static void cgroup_pidlist_stop(struct s
static void *cgroup_pidlist_next(struct seq_file *s, void *v, loff_t *pos)
{
struct kernfs_open_file *of = s->private;
- struct cgroup_pidlist *l = of->priv;
+ struct cgroup_file_ctx *ctx = of->priv;
+ struct cgroup_pidlist *l = ctx->procs1.pidlist;
pid_t *p = v;
pid_t *end = l->list + l->length;
/*
@@ -3648,6 +3648,7 @@ static int cgroup_cpu_pressure_show(stru
static ssize_t cgroup_pressure_write(struct kernfs_open_file *of, char *buf,
size_t nbytes, enum psi_res res)
{
+ struct cgroup_file_ctx *ctx = of->priv;
struct psi_trigger *new;
struct cgroup *cgrp;
struct psi_group *psi;
@@ -3660,7 +3661,7 @@ static ssize_t cgroup_pressure_write(str
cgroup_kn_unlock(of->kn);
/* Allow only one trigger per file descriptor */
- if (of->priv) {
+ if (ctx->psi.trigger) {
cgroup_put(cgrp);
return -EBUSY;
}
@@ -3672,7 +3673,7 @@ static ssize_t cgroup_pressure_write(str
return PTR_ERR(new);
}
- smp_store_release(&of->priv, new);
+ smp_store_release(&ctx->psi.trigger, new);
cgroup_put(cgrp);
return nbytes;
@@ -3702,12 +3703,15 @@ static ssize_t cgroup_cpu_pressure_write
static __poll_t cgroup_pressure_poll(struct kernfs_open_file *of,
poll_table *pt)
{
- return psi_trigger_poll(&of->priv, of->file, pt);
+ struct cgroup_file_ctx *ctx = of->priv;
+ return psi_trigger_poll(&ctx->psi.trigger, of->file, pt);
}
static void cgroup_pressure_release(struct kernfs_open_file *of)
{
- psi_trigger_destroy(of->priv);
+ struct cgroup_file_ctx *ctx = of->priv;
+
+ psi_trigger_destroy(ctx->psi.trigger);
}
#endif /* CONFIG_PSI */
@@ -3748,18 +3752,31 @@ static ssize_t cgroup_freeze_write(struc
static int cgroup_file_open(struct kernfs_open_file *of)
{
struct cftype *cft = of->kn->priv;
+ struct cgroup_file_ctx *ctx;
+ int ret;
- if (cft->open)
- return cft->open(of);
- return 0;
+ ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+ of->priv = ctx;
+
+ if (!cft->open)
+ return 0;
+
+ ret = cft->open(of);
+ if (ret)
+ kfree(ctx);
+ return ret;
}
static void cgroup_file_release(struct kernfs_open_file *of)
{
struct cftype *cft = of->kn->priv;
+ struct cgroup_file_ctx *ctx = of->priv;
if (cft->release)
cft->release(of);
+ kfree(ctx);
}
static ssize_t cgroup_file_write(struct kernfs_open_file *of, char *buf,
@@ -4687,21 +4704,21 @@ void css_task_iter_end(struct css_task_i
static void cgroup_procs_release(struct kernfs_open_file *of)
{
- if (of->priv) {
- css_task_iter_end(of->priv);
- kfree(of->priv);
- }
+ struct cgroup_file_ctx *ctx = of->priv;
+
+ if (ctx->procs.started)
+ css_task_iter_end(&ctx->procs.iter);
}
static void *cgroup_procs_next(struct seq_file *s, void *v, loff_t *pos)
{
struct kernfs_open_file *of = s->private;
- struct css_task_iter *it = of->priv;
+ struct cgroup_file_ctx *ctx = of->priv;
if (pos)
(*pos)++;
- return css_task_iter_next(it);
+ return css_task_iter_next(&ctx->procs.iter);
}
static void *__cgroup_procs_start(struct seq_file *s, loff_t *pos,
@@ -4709,21 +4726,18 @@ static void *__cgroup_procs_start(struct
{
struct kernfs_open_file *of = s->private;
struct cgroup *cgrp = seq_css(s)->cgroup;
- struct css_task_iter *it = of->priv;
+ struct cgroup_file_ctx *ctx = of->priv;
+ struct css_task_iter *it = &ctx->procs.iter;
/*
* When a seq_file is seeked, it's always traversed sequentially
* from position 0, so we can simply keep iterating on !0 *pos.
*/
- if (!it) {
+ if (!ctx->procs.started) {
if (WARN_ON_ONCE((*pos)))
return ERR_PTR(-EINVAL);
-
- it = kzalloc(sizeof(*it), GFP_KERNEL);
- if (!it)
- return ERR_PTR(-ENOMEM);
- of->priv = it;
css_task_iter_start(&cgrp->self, iter_flags, it);
+ ctx->procs.started = true;
} else if (!(*pos)) {
css_task_iter_end(it);
css_task_iter_start(&cgrp->self, iter_flags, it);