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Diffstat (limited to 'mm/memcontrol.c')
-rw-r--r--mm/memcontrol.c188
1 files changed, 98 insertions, 90 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index a9559b91603c..a2c7bcb0e6eb 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -526,18 +526,14 @@ static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg)
static inline unsigned short mem_cgroup_id(struct mem_cgroup *memcg)
{
- /*
- * The ID of the root cgroup is 0, but memcg treat 0 as an
- * invalid ID, so we return (cgroup_id + 1).
- */
- return memcg->css.cgroup->id + 1;
+ return memcg->css.id;
}
static inline struct mem_cgroup *mem_cgroup_from_id(unsigned short id)
{
struct cgroup_subsys_state *css;
- css = css_from_id(id - 1, &memory_cgrp_subsys);
+ css = css_from_id(id, &memory_cgrp_subsys);
return mem_cgroup_from_css(css);
}
@@ -570,7 +566,8 @@ void sock_update_memcg(struct sock *sk)
memcg = mem_cgroup_from_task(current);
cg_proto = sk->sk_prot->proto_cgroup(memcg);
if (!mem_cgroup_is_root(memcg) &&
- memcg_proto_active(cg_proto) && css_tryget(&memcg->css)) {
+ memcg_proto_active(cg_proto) &&
+ css_tryget_online(&memcg->css)) {
sk->sk_cgrp = cg_proto;
}
rcu_read_unlock();
@@ -831,7 +828,7 @@ retry:
*/
__mem_cgroup_remove_exceeded(mz, mctz);
if (!res_counter_soft_limit_excess(&mz->memcg->res) ||
- !css_tryget(&mz->memcg->css))
+ !css_tryget_online(&mz->memcg->css))
goto retry;
done:
return mz;
@@ -1073,7 +1070,7 @@ static struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm)
if (unlikely(!memcg))
memcg = root_mem_cgroup;
}
- } while (!css_tryget(&memcg->css));
+ } while (!css_tryget_online(&memcg->css));
rcu_read_unlock();
return memcg;
}
@@ -1110,7 +1107,8 @@ skip_node:
*/
if (next_css) {
if ((next_css == &root->css) ||
- ((next_css->flags & CSS_ONLINE) && css_tryget(next_css)))
+ ((next_css->flags & CSS_ONLINE) &&
+ css_tryget_online(next_css)))
return mem_cgroup_from_css(next_css);
prev_css = next_css;
@@ -1156,7 +1154,7 @@ mem_cgroup_iter_load(struct mem_cgroup_reclaim_iter *iter,
* would be returned all the time.
*/
if (position && position != root &&
- !css_tryget(&position->css))
+ !css_tryget_online(&position->css))
position = NULL;
}
return position;
@@ -1533,7 +1531,7 @@ static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg)
int mem_cgroup_swappiness(struct mem_cgroup *memcg)
{
/* root ? */
- if (mem_cgroup_disabled() || !css_parent(&memcg->css))
+ if (mem_cgroup_disabled() || !memcg->css.parent)
return vm_swappiness;
return memcg->swappiness;
@@ -2769,9 +2767,9 @@ static void __mem_cgroup_cancel_local_charge(struct mem_cgroup *memcg,
/*
* A helper function to get mem_cgroup from ID. must be called under
- * rcu_read_lock(). The caller is responsible for calling css_tryget if
- * the mem_cgroup is used for charging. (dropping refcnt from swap can be
- * called against removed memcg.)
+ * rcu_read_lock(). The caller is responsible for calling
+ * css_tryget_online() if the mem_cgroup is used for charging. (dropping
+ * refcnt from swap can be called against removed memcg.)
*/
static struct mem_cgroup *mem_cgroup_lookup(unsigned short id)
{
@@ -2794,14 +2792,14 @@ struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page)
lock_page_cgroup(pc);
if (PageCgroupUsed(pc)) {
memcg = pc->mem_cgroup;
- if (memcg && !css_tryget(&memcg->css))
+ if (memcg && !css_tryget_online(&memcg->css))
memcg = NULL;
} else if (PageSwapCache(page)) {
ent.val = page_private(page);
id = lookup_swap_cgroup_id(ent);
rcu_read_lock();
memcg = mem_cgroup_lookup(id);
- if (memcg && !css_tryget(&memcg->css))
+ if (memcg && !css_tryget_online(&memcg->css))
memcg = NULL;
rcu_read_unlock();
}
@@ -3365,7 +3363,7 @@ struct kmem_cache *__memcg_kmem_get_cache(struct kmem_cache *cachep,
}
/* The corresponding put will be done in the workqueue. */
- if (!css_tryget(&memcg->css))
+ if (!css_tryget_online(&memcg->css))
goto out;
rcu_read_unlock();
@@ -4125,8 +4123,8 @@ void mem_cgroup_uncharge_swap(swp_entry_t ent)
memcg = mem_cgroup_lookup(id);
if (memcg) {
/*
- * We uncharge this because swap is freed.
- * This memcg can be obsolete one. We avoid calling css_tryget
+ * We uncharge this because swap is freed. This memcg can
+ * be obsolete one. We avoid calling css_tryget_online().
*/
if (!mem_cgroup_is_root(memcg))
res_counter_uncharge(&memcg->memsw, PAGE_SIZE);
@@ -4711,18 +4709,28 @@ static void mem_cgroup_reparent_charges(struct mem_cgroup *memcg)
} while (usage > 0);
}
+/*
+ * Test whether @memcg has children, dead or alive. Note that this
+ * function doesn't care whether @memcg has use_hierarchy enabled and
+ * returns %true if there are child csses according to the cgroup
+ * hierarchy. Testing use_hierarchy is the caller's responsiblity.
+ */
static inline bool memcg_has_children(struct mem_cgroup *memcg)
{
- lockdep_assert_held(&memcg_create_mutex);
+ bool ret;
+
/*
- * The lock does not prevent addition or deletion to the list
- * of children, but it prevents a new child from being
- * initialized based on this parent in css_online(), so it's
- * enough to decide whether hierarchically inherited
- * attributes can still be changed or not.
+ * The lock does not prevent addition or deletion of children, but
+ * it prevents a new child from being initialized based on this
+ * parent in css_online(), so it's enough to decide whether
+ * hierarchically inherited attributes can still be changed or not.
*/
- return memcg->use_hierarchy &&
- !list_empty(&memcg->css.cgroup->children);
+ lockdep_assert_held(&memcg_create_mutex);
+
+ rcu_read_lock();
+ ret = css_next_child(NULL, &memcg->css);
+ rcu_read_unlock();
+ return ret;
}
/*
@@ -4734,11 +4742,6 @@ static inline bool memcg_has_children(struct mem_cgroup *memcg)
static int mem_cgroup_force_empty(struct mem_cgroup *memcg)
{
int nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
- struct cgroup *cgrp = memcg->css.cgroup;
-
- /* returns EBUSY if there is a task or if we come here twice. */
- if (cgroup_has_tasks(cgrp) || !list_empty(&cgrp->children))
- return -EBUSY;
/* we call try-to-free pages for make this cgroup empty */
lru_add_drain_all();
@@ -4758,20 +4761,19 @@ static int mem_cgroup_force_empty(struct mem_cgroup *memcg)
}
}
- lru_add_drain();
- mem_cgroup_reparent_charges(memcg);
return 0;
}
-static int mem_cgroup_force_empty_write(struct cgroup_subsys_state *css,
- unsigned int event)
+static ssize_t mem_cgroup_force_empty_write(struct kernfs_open_file *of,
+ char *buf, size_t nbytes,
+ loff_t off)
{
- struct mem_cgroup *memcg = mem_cgroup_from_css(css);
+ struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
if (mem_cgroup_is_root(memcg))
return -EINVAL;
- return mem_cgroup_force_empty(memcg);
+ return mem_cgroup_force_empty(memcg) ?: nbytes;
}
static u64 mem_cgroup_hierarchy_read(struct cgroup_subsys_state *css,
@@ -4785,7 +4787,7 @@ static int mem_cgroup_hierarchy_write(struct cgroup_subsys_state *css,
{
int retval = 0;
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
- struct mem_cgroup *parent_memcg = mem_cgroup_from_css(css_parent(&memcg->css));
+ struct mem_cgroup *parent_memcg = mem_cgroup_from_css(memcg->css.parent);
mutex_lock(&memcg_create_mutex);
@@ -4802,7 +4804,7 @@ static int mem_cgroup_hierarchy_write(struct cgroup_subsys_state *css,
*/
if ((!parent_memcg || !parent_memcg->use_hierarchy) &&
(val == 1 || val == 0)) {
- if (list_empty(&memcg->css.cgroup->children))
+ if (!memcg_has_children(memcg))
memcg->use_hierarchy = val;
else
retval = -EBUSY;
@@ -4919,7 +4921,8 @@ static int __memcg_activate_kmem(struct mem_cgroup *memcg,
* of course permitted.
*/
mutex_lock(&memcg_create_mutex);
- if (cgroup_has_tasks(memcg->css.cgroup) || memcg_has_children(memcg))
+ if (cgroup_has_tasks(memcg->css.cgroup) ||
+ (memcg->use_hierarchy && memcg_has_children(memcg)))
err = -EBUSY;
mutex_unlock(&memcg_create_mutex);
if (err)
@@ -5021,17 +5024,18 @@ static int memcg_update_kmem_limit(struct mem_cgroup *memcg,
* The user of this function is...
* RES_LIMIT.
*/
-static int mem_cgroup_write(struct cgroup_subsys_state *css, struct cftype *cft,
- char *buffer)
+static ssize_t mem_cgroup_write(struct kernfs_open_file *of,
+ char *buf, size_t nbytes, loff_t off)
{
- struct mem_cgroup *memcg = mem_cgroup_from_css(css);
+ struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
enum res_type type;
int name;
unsigned long long val;
int ret;
- type = MEMFILE_TYPE(cft->private);
- name = MEMFILE_ATTR(cft->private);
+ buf = strstrip(buf);
+ type = MEMFILE_TYPE(of_cft(of)->private);
+ name = MEMFILE_ATTR(of_cft(of)->private);
switch (name) {
case RES_LIMIT:
@@ -5040,7 +5044,7 @@ static int mem_cgroup_write(struct cgroup_subsys_state *css, struct cftype *cft,
break;
}
/* This function does all necessary parse...reuse it */
- ret = res_counter_memparse_write_strategy(buffer, &val);
+ ret = res_counter_memparse_write_strategy(buf, &val);
if (ret)
break;
if (type == _MEM)
@@ -5053,7 +5057,7 @@ static int mem_cgroup_write(struct cgroup_subsys_state *css, struct cftype *cft,
return -EINVAL;
break;
case RES_SOFT_LIMIT:
- ret = res_counter_memparse_write_strategy(buffer, &val);
+ ret = res_counter_memparse_write_strategy(buf, &val);
if (ret)
break;
/*
@@ -5070,7 +5074,7 @@ static int mem_cgroup_write(struct cgroup_subsys_state *css, struct cftype *cft,
ret = -EINVAL; /* should be BUG() ? */
break;
}
- return ret;
+ return ret ?: nbytes;
}
static void memcg_get_hierarchical_limit(struct mem_cgroup *memcg,
@@ -5083,8 +5087,8 @@ static void memcg_get_hierarchical_limit(struct mem_cgroup *memcg,
if (!memcg->use_hierarchy)
goto out;
- while (css_parent(&memcg->css)) {
- memcg = mem_cgroup_from_css(css_parent(&memcg->css));
+ while (memcg->css.parent) {
+ memcg = mem_cgroup_from_css(memcg->css.parent);
if (!memcg->use_hierarchy)
break;
tmp = res_counter_read_u64(&memcg->res, RES_LIMIT);
@@ -5097,14 +5101,15 @@ out:
*memsw_limit = min_memsw_limit;
}
-static int mem_cgroup_reset(struct cgroup_subsys_state *css, unsigned int event)
+static ssize_t mem_cgroup_reset(struct kernfs_open_file *of, char *buf,
+ size_t nbytes, loff_t off)
{
- struct mem_cgroup *memcg = mem_cgroup_from_css(css);
+ struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
int name;
enum res_type type;
- type = MEMFILE_TYPE(event);
- name = MEMFILE_ATTR(event);
+ type = MEMFILE_TYPE(of_cft(of)->private);
+ name = MEMFILE_ATTR(of_cft(of)->private);
switch (name) {
case RES_MAX_USAGE:
@@ -5129,7 +5134,7 @@ static int mem_cgroup_reset(struct cgroup_subsys_state *css, unsigned int event)
break;
}
- return 0;
+ return nbytes;
}
static u64 mem_cgroup_move_charge_read(struct cgroup_subsys_state *css,
@@ -5322,7 +5327,7 @@ static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css,
if (val > 100)
return -EINVAL;
- if (css_parent(css))
+ if (css->parent)
memcg->swappiness = val;
else
vm_swappiness = val;
@@ -5659,7 +5664,7 @@ static int mem_cgroup_oom_control_write(struct cgroup_subsys_state *css,
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
/* cannot set to root cgroup and only 0 and 1 are allowed */
- if (!css_parent(css) || !((val == 0) || (val == 1)))
+ if (!css->parent || !((val == 0) || (val == 1)))
return -EINVAL;
memcg->oom_kill_disable = val;
@@ -5705,10 +5710,10 @@ static void kmem_cgroup_css_offline(struct mem_cgroup *memcg)
* which is then paired with css_put during uncharge resp. here.
*
* Although this might sound strange as this path is called from
- * css_offline() when the referencemight have dropped down to 0
- * and shouldn't be incremented anymore (css_tryget would fail)
- * we do not have other options because of the kmem allocations
- * lifetime.
+ * css_offline() when the referencemight have dropped down to 0 and
+ * shouldn't be incremented anymore (css_tryget_online() would
+ * fail) we do not have other options because of the kmem
+ * allocations lifetime.
*/
css_get(&memcg->css);
@@ -5827,9 +5832,10 @@ static void memcg_event_ptable_queue_proc(struct file *file,
* Input must be in format '<event_fd> <control_fd> <args>'.
* Interpretation of args is defined by control file implementation.
*/
-static int memcg_write_event_control(struct cgroup_subsys_state *css,
- struct cftype *cft, char *buffer)
+static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
+ char *buf, size_t nbytes, loff_t off)
{
+ struct cgroup_subsys_state *css = of_css(of);
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
struct mem_cgroup_event *event;
struct cgroup_subsys_state *cfile_css;
@@ -5840,15 +5846,17 @@ static int memcg_write_event_control(struct cgroup_subsys_state *css,
char *endp;
int ret;
- efd = simple_strtoul(buffer, &endp, 10);
+ buf = strstrip(buf);
+
+ efd = simple_strtoul(buf, &endp, 10);
if (*endp != ' ')
return -EINVAL;
- buffer = endp + 1;
+ buf = endp + 1;
- cfd = simple_strtoul(buffer, &endp, 10);
+ cfd = simple_strtoul(buf, &endp, 10);
if ((*endp != ' ') && (*endp != '\0'))
return -EINVAL;
- buffer = endp + 1;
+ buf = endp + 1;
event = kzalloc(sizeof(*event), GFP_KERNEL);
if (!event)
@@ -5916,8 +5924,8 @@ static int memcg_write_event_control(struct cgroup_subsys_state *css,
* automatically removed on cgroup destruction but the removal is
* asynchronous, so take an extra ref on @css.
*/
- cfile_css = css_tryget_from_dir(cfile.file->f_dentry->d_parent,
- &memory_cgrp_subsys);
+ cfile_css = css_tryget_online_from_dir(cfile.file->f_dentry->d_parent,
+ &memory_cgrp_subsys);
ret = -EINVAL;
if (IS_ERR(cfile_css))
goto out_put_cfile;
@@ -5926,7 +5934,7 @@ static int memcg_write_event_control(struct cgroup_subsys_state *css,
goto out_put_cfile;
}
- ret = event->register_event(memcg, event->eventfd, buffer);
+ ret = event->register_event(memcg, event->eventfd, buf);
if (ret)
goto out_put_css;
@@ -5939,7 +5947,7 @@ static int memcg_write_event_control(struct cgroup_subsys_state *css,
fdput(cfile);
fdput(efile);
- return 0;
+ return nbytes;
out_put_css:
css_put(css);
@@ -5964,25 +5972,25 @@ static struct cftype mem_cgroup_files[] = {
{
.name = "max_usage_in_bytes",
.private = MEMFILE_PRIVATE(_MEM, RES_MAX_USAGE),
- .trigger = mem_cgroup_reset,
+ .write = mem_cgroup_reset,
.read_u64 = mem_cgroup_read_u64,
},
{
.name = "limit_in_bytes",
.private = MEMFILE_PRIVATE(_MEM, RES_LIMIT),
- .write_string = mem_cgroup_write,
+ .write = mem_cgroup_write,
.read_u64 = mem_cgroup_read_u64,
},
{
.name = "soft_limit_in_bytes",
.private = MEMFILE_PRIVATE(_MEM, RES_SOFT_LIMIT),
- .write_string = mem_cgroup_write,
+ .write = mem_cgroup_write,
.read_u64 = mem_cgroup_read_u64,
},
{
.name = "failcnt",
.private = MEMFILE_PRIVATE(_MEM, RES_FAILCNT),
- .trigger = mem_cgroup_reset,
+ .write = mem_cgroup_reset,
.read_u64 = mem_cgroup_read_u64,
},
{
@@ -5991,7 +5999,7 @@ static struct cftype mem_cgroup_files[] = {
},
{
.name = "force_empty",
- .trigger = mem_cgroup_force_empty_write,
+ .write = mem_cgroup_force_empty_write,
},
{
.name = "use_hierarchy",
@@ -6001,7 +6009,7 @@ static struct cftype mem_cgroup_files[] = {
},
{
.name = "cgroup.event_control", /* XXX: for compat */
- .write_string = memcg_write_event_control,
+ .write = memcg_write_event_control,
.flags = CFTYPE_NO_PREFIX,
.mode = S_IWUGO,
},
@@ -6034,7 +6042,7 @@ static struct cftype mem_cgroup_files[] = {
{
.name = "kmem.limit_in_bytes",
.private = MEMFILE_PRIVATE(_KMEM, RES_LIMIT),
- .write_string = mem_cgroup_write,
+ .write = mem_cgroup_write,
.read_u64 = mem_cgroup_read_u64,
},
{
@@ -6045,13 +6053,13 @@ static struct cftype mem_cgroup_files[] = {
{
.name = "kmem.failcnt",
.private = MEMFILE_PRIVATE(_KMEM, RES_FAILCNT),
- .trigger = mem_cgroup_reset,
+ .write = mem_cgroup_reset,
.read_u64 = mem_cgroup_read_u64,
},
{
.name = "kmem.max_usage_in_bytes",
.private = MEMFILE_PRIVATE(_KMEM, RES_MAX_USAGE),
- .trigger = mem_cgroup_reset,
+ .write = mem_cgroup_reset,
.read_u64 = mem_cgroup_read_u64,
},
#ifdef CONFIG_SLABINFO
@@ -6074,19 +6082,19 @@ static struct cftype memsw_cgroup_files[] = {
{
.name = "memsw.max_usage_in_bytes",
.private = MEMFILE_PRIVATE(_MEMSWAP, RES_MAX_USAGE),
- .trigger = mem_cgroup_reset,
+ .write = mem_cgroup_reset,
.read_u64 = mem_cgroup_read_u64,
},
{
.name = "memsw.limit_in_bytes",
.private = MEMFILE_PRIVATE(_MEMSWAP, RES_LIMIT),
- .write_string = mem_cgroup_write,
+ .write = mem_cgroup_write,
.read_u64 = mem_cgroup_read_u64,
},
{
.name = "memsw.failcnt",
.private = MEMFILE_PRIVATE(_MEMSWAP, RES_FAILCNT),
- .trigger = mem_cgroup_reset,
+ .write = mem_cgroup_reset,
.read_u64 = mem_cgroup_read_u64,
},
{ }, /* terminate */
@@ -6264,9 +6272,9 @@ static int
mem_cgroup_css_online(struct cgroup_subsys_state *css)
{
struct mem_cgroup *memcg = mem_cgroup_from_css(css);
- struct mem_cgroup *parent = mem_cgroup_from_css(css_parent(css));
+ struct mem_cgroup *parent = mem_cgroup_from_css(css->parent);
- if (css->cgroup->id > MEM_CGROUP_ID_MAX)
+ if (css->id > MEM_CGROUP_ID_MAX)
return -ENOSPC;
if (!parent)
@@ -6361,7 +6369,7 @@ static void mem_cgroup_css_free(struct cgroup_subsys_state *css)
/*
* XXX: css_offline() would be where we should reparent all
* memory to prepare the cgroup for destruction. However,
- * memcg does not do css_tryget() and res_counter charging
+ * memcg does not do css_tryget_online() and res_counter charging
* under the same RCU lock region, which means that charging
* could race with offlining. Offlining only happens to
* cgroups with no tasks in them but charges can show up
@@ -6375,9 +6383,9 @@ static void mem_cgroup_css_free(struct cgroup_subsys_state *css)
* lookup_swap_cgroup_id()
* rcu_read_lock()
* mem_cgroup_lookup()
- * css_tryget()
+ * css_tryget_online()
* rcu_read_unlock()
- * disable css_tryget()
+ * disable css_tryget_online()
* call_rcu()
* offline_css()
* reparent_charges()
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-12-03 11:01:42 +0000