diff options
Diffstat (limited to 'mm/memcontrol.c')
| -rw-r--r-- | mm/memcontrol.c | 32 |
1 files changed, 20 insertions, 12 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 5381afb23d58..19622328e4b5 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2772,8 +2772,10 @@ static void memcg_schedule_kmem_cache_create(struct mem_cgroup *memcg, return; cw = kmalloc(sizeof(*cw), GFP_NOWAIT | __GFP_NOWARN); - if (!cw) + if (!cw) { + css_put(&memcg->css); return; + } cw->memcg = memcg; cw->cachep = cachep; @@ -3186,7 +3188,7 @@ unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order, * 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. + * hierarchy. Testing use_hierarchy is the caller's responsibility. */ static inline bool memcg_has_children(struct mem_cgroup *memcg) { @@ -4838,7 +4840,7 @@ static struct cftype mem_cgroup_legacy_files[] = { * limited to 16 bit (MEM_CGROUP_ID_MAX), limiting the total number of * memory-controlled cgroups to 64k. * - * However, there usually are many references to the oflline CSS after + * However, there usually are many references to the offline CSS after * the cgroup has been destroyed, such as page cache or reclaimable * slab objects, that don't need to hang on to the ID. We want to keep * those dead CSS from occupying IDs, or we might quickly exhaust the @@ -5614,9 +5616,9 @@ static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm) { unsigned long precharge; - down_read(&mm->mmap_sem); + mmap_read_lock(mm); walk_page_range(mm, 0, mm->highest_vm_end, &precharge_walk_ops, NULL); - up_read(&mm->mmap_sem); + mmap_read_unlock(mm); precharge = mc.precharge; mc.precharge = 0; @@ -5899,9 +5901,9 @@ static void mem_cgroup_move_charge(void) atomic_inc(&mc.from->moving_account); synchronize_rcu(); retry: - if (unlikely(!down_read_trylock(&mc.mm->mmap_sem))) { + if (unlikely(!mmap_read_trylock(mc.mm))) { /* - * Someone who are holding the mmap_sem might be waiting in + * Someone who are holding the mmap_lock might be waiting in * waitq. So we cancel all extra charges, wake up all waiters, * and retry. Because we cancel precharges, we might not be able * to move enough charges, but moving charge is a best-effort @@ -5918,7 +5920,7 @@ retry: walk_page_range(mc.mm, 0, mc.mm->highest_vm_end, &charge_walk_ops, NULL); - up_read(&mc.mm->mmap_sem); + mmap_read_unlock(mc.mm); atomic_dec(&mc.from->moving_account); } @@ -6360,11 +6362,16 @@ static unsigned long effective_protection(unsigned long usage, * We're using unprotected memory for the weight so that if * some cgroups DO claim explicit protection, we don't protect * the same bytes twice. + * + * Check both usage and parent_usage against the respective + * protected values. One should imply the other, but they + * aren't read atomically - make sure the division is sane. */ if (!(cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_RECURSIVE_PROT)) return ep; - - if (parent_effective > siblings_protected && usage > protected) { + if (parent_effective > siblings_protected && + parent_usage > siblings_protected && + usage > protected) { unsigned long unclaimed; unclaimed = parent_effective - siblings_protected; @@ -6416,7 +6423,7 @@ enum mem_cgroup_protection mem_cgroup_protected(struct mem_cgroup *root, if (parent == root) { memcg->memory.emin = READ_ONCE(memcg->memory.min); - memcg->memory.elow = memcg->memory.low; + memcg->memory.elow = READ_ONCE(memcg->memory.low); goto out; } @@ -6428,7 +6435,8 @@ enum mem_cgroup_protection mem_cgroup_protected(struct mem_cgroup *root, atomic_long_read(&parent->memory.children_min_usage))); WRITE_ONCE(memcg->memory.elow, effective_protection(usage, parent_usage, - memcg->memory.low, READ_ONCE(parent->memory.elow), + READ_ONCE(memcg->memory.low), + READ_ONCE(parent->memory.elow), atomic_long_read(&parent->memory.children_low_usage))); out: |