struct mem_cgroup *root_mem_cgroup __read_mostly;
-#define MEM_CGROUP_RECLAIM_RETRIES 5
-
/* Socket memory accounting disabled? */
static bool cgroup_memory_nosocket;
.gfp_mask = gfp_mask,
.order = order,
};
- bool ret;
+ bool ret = true;
if (mutex_lock_killable(&oom_lock))
return true;
+
+ if (mem_cgroup_margin(memcg) >= (1 << order))
+ goto unlock;
+
/*
* A few threads which were not waiting at mutex_lock_killable() can
* fail to bail out. Therefore, check again after holding oom_lock.
*/
ret = should_force_charge() || out_of_memory(&oc);
+
+unlock:
mutex_unlock(&oom_lock);
return ret;
}
return 0;
}
-static void reclaim_high(struct mem_cgroup *memcg,
- unsigned int nr_pages,
- gfp_t gfp_mask)
+static unsigned long reclaim_high(struct mem_cgroup *memcg,
+ unsigned int nr_pages,
+ gfp_t gfp_mask)
{
+ unsigned long nr_reclaimed = 0;
+
do {
+ unsigned long pflags;
+
if (page_counter_read(&memcg->memory) <=
READ_ONCE(memcg->memory.high))
continue;
+
memcg_memory_event(memcg, MEMCG_HIGH);
- try_to_free_mem_cgroup_pages(memcg, nr_pages, gfp_mask, true);
+
+ psi_memstall_enter(&pflags);
+ nr_reclaimed += try_to_free_mem_cgroup_pages(memcg, nr_pages,
+ gfp_mask, true);
+ psi_memstall_leave(&pflags);
} while ((memcg = parent_mem_cgroup(memcg)) &&
!mem_cgroup_is_root(memcg));
+
+ return nr_reclaimed;
}
static void high_work_func(struct work_struct *work)
{
unsigned long penalty_jiffies;
unsigned long pflags;
+ unsigned long nr_reclaimed;
unsigned int nr_pages = current->memcg_nr_pages_over_high;
+ int nr_retries = MAX_RECLAIM_RETRIES;
struct mem_cgroup *memcg;
+ bool in_retry = false;
if (likely(!nr_pages))
return;
memcg = get_mem_cgroup_from_mm(current->mm);
- reclaim_high(memcg, nr_pages, GFP_KERNEL);
current->memcg_nr_pages_over_high = 0;
+retry_reclaim:
+ /*
+ * The allocating task should reclaim at least the batch size, but for
+ * subsequent retries we only want to do what's necessary to prevent oom
+ * or breaching resource isolation.
+ *
+ * This is distinct from memory.max or page allocator behaviour because
+ * memory.high is currently batched, whereas memory.max and the page
+ * allocator run every time an allocation is made.
+ */
+ nr_reclaimed = reclaim_high(memcg,
+ in_retry ? SWAP_CLUSTER_MAX : nr_pages,
+ GFP_KERNEL);
+
/*
* memory.high is breached and reclaim is unable to keep up. Throttle
* allocators proactively to slow down excessive growth.
if (penalty_jiffies <= HZ / 100)
goto out;
+ /*
+ * If reclaim is making forward progress but we're still over
+ * memory.high, we want to encourage that rather than doing allocator
+ * throttling.
+ */
+ if (nr_reclaimed || nr_retries--) {
+ in_retry = true;
+ goto retry_reclaim;
+ }
+
/*
* If we exit early, we're guaranteed to die (since
* schedule_timeout_killable sets TASK_KILLABLE). This means we don't
unsigned int nr_pages)
{
unsigned int batch = max(MEMCG_CHARGE_BATCH, nr_pages);
- int nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
+ int nr_retries = MAX_RECLAIM_RETRIES;
struct mem_cgroup *mem_over_limit;
struct page_counter *counter;
+ enum oom_status oom_status;
unsigned long nr_reclaimed;
bool may_swap = true;
bool drained = false;
- enum oom_status oom_status;
+ unsigned long pflags;
if (mem_cgroup_is_root(memcg))
return 0;
memcg_memory_event(mem_over_limit, MEMCG_MAX);
+ psi_memstall_enter(&pflags);
nr_reclaimed = try_to_free_mem_cgroup_pages(mem_over_limit, nr_pages,
gfp_mask, may_swap);
+ psi_memstall_leave(&pflags);
if (mem_cgroup_margin(mem_over_limit) >= nr_pages)
goto retry;
get_order(nr_pages * PAGE_SIZE));
switch (oom_status) {
case OOM_SUCCESS:
- nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
+ nr_retries = MAX_RECLAIM_RETRIES;
goto retry;
case OOM_FAILED:
goto force;
*/
static int mem_cgroup_force_empty(struct mem_cgroup *memcg)
{
- int nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
+ int nr_retries = MAX_RECLAIM_RETRIES;
/* we call try-to-free pages for make this cgroup empty */
lru_add_drain_all();
char *buf, size_t nbytes, loff_t off)
{
struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
- unsigned int nr_retries = MEM_CGROUP_RECLAIM_RETRIES;
+ unsigned int nr_retries = MAX_RECLAIM_RETRIES;
bool drained = false;
unsigned long high;
int err;
if (err)
return err;
- page_counter_set_high(&memcg->memory, high);
-
for (;;) {
unsigned long nr_pages = page_counter_read(&memcg->memory);
unsigned long reclaimed;
break;
}
+ page_counter_set_high(&memcg->memory, high);
+
+ memcg_wb_domain_size_changed(memcg);
+
return nbytes;
}
char *buf, size_t nbytes, loff_t off)
{
struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of));
- unsigned int nr_reclaims = MEM_CGROUP_RECLAIM_RETRIES;
+ unsigned int nr_reclaims = MAX_RECLAIM_RETRIES;
bool drained = false;
unsigned long max;
int err;
*
* WARNING: This function is not stateless! It can only be used as part
* of a top-down tree iteration, not for isolated queries.
- *
- * Returns one of the following:
- * MEMCG_PROT_NONE: cgroup memory is not protected
- * MEMCG_PROT_LOW: cgroup memory is protected as long there is
- * an unprotected supply of reclaimable memory from other cgroups.
- * MEMCG_PROT_MIN: cgroup memory is protected
*/
-enum mem_cgroup_protection mem_cgroup_protected(struct mem_cgroup *root,
- struct mem_cgroup *memcg)
+void mem_cgroup_calculate_protection(struct mem_cgroup *root,
+ struct mem_cgroup *memcg)
{
unsigned long usage, parent_usage;
struct mem_cgroup *parent;
if (mem_cgroup_disabled())
- return MEMCG_PROT_NONE;
+ return;
if (!root)
root = root_mem_cgroup;
+
+ /*
+ * Effective values of the reclaim targets are ignored so they
+ * can be stale. Have a look at mem_cgroup_protection for more
+ * details.
+ * TODO: calculation should be more robust so that we do not need
+ * that special casing.
+ */
if (memcg == root)
- return MEMCG_PROT_NONE;
+ return;
usage = page_counter_read(&memcg->memory);
if (!usage)
- return MEMCG_PROT_NONE;
+ return;
parent = parent_mem_cgroup(memcg);
/* No parent means a non-hierarchical mode on v1 memcg */
if (!parent)
- return MEMCG_PROT_NONE;
+ return;
if (parent == root) {
memcg->memory.emin = READ_ONCE(memcg->memory.min);
memcg->memory.elow = READ_ONCE(memcg->memory.low);
- goto out;
+ return;
}
parent_usage = page_counter_read(&parent->memory);
READ_ONCE(memcg->memory.low),
READ_ONCE(parent->memory.elow),
atomic_long_read(&parent->memory.children_low_usage)));
-
-out:
- if (usage <= memcg->memory.emin)
- return MEMCG_PROT_MIN;
- else if (usage <= memcg->memory.elow)
- return MEMCG_PROT_LOW;
- else
- return MEMCG_PROT_NONE;
}
/**
projects / linux-2.6-microblaze.git / blobdiff