diff options
Diffstat (limited to 'mm/memcontrol.c')
| -rw-r--r-- | mm/memcontrol.c | 1328 |
1 files changed, 748 insertions, 580 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 7b3503d12aaf..be810c1fbfc3 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -29,6 +29,7 @@ #include <linux/page_counter.h> #include <linux/memcontrol.h> #include <linux/cgroup.h> +#include <linux/cpuset.h> #include <linux/sched/mm.h> #include <linux/shmem_fs.h> #include <linux/hugetlb.h> @@ -50,7 +51,6 @@ #include <linux/spinlock.h> #include <linux/fs.h> #include <linux/seq_file.h> -#include <linux/parser.h> #include <linux/vmpressure.h> #include <linux/memremap.h> #include <linux/mm_inline.h> @@ -81,6 +81,7 @@ struct cgroup_subsys memory_cgrp_subsys __read_mostly; EXPORT_SYMBOL(memory_cgrp_subsys); struct mem_cgroup *root_mem_cgroup __read_mostly; +EXPORT_SYMBOL(root_mem_cgroup); /* Active memory cgroup to use from an interrupt context */ DEFINE_PER_CPU(struct mem_cgroup *, int_active_memcg); @@ -95,6 +96,9 @@ static bool cgroup_memory_nokmem __ro_after_init; /* BPF memory accounting disabled? */ static bool cgroup_memory_nobpf __ro_after_init; +static struct kmem_cache *memcg_cachep; +static struct kmem_cache *memcg_pn_cachep; + #ifdef CONFIG_CGROUP_WRITEBACK static DECLARE_WAIT_QUEUE_HEAD(memcg_cgwb_frn_waitq); #endif @@ -129,8 +133,7 @@ bool mem_cgroup_kmem_disabled(void) return cgroup_memory_nokmem; } -static void obj_cgroup_uncharge_pages(struct obj_cgroup *objcg, - unsigned int nr_pages); +static void memcg_uncharge(struct mem_cgroup *memcg, unsigned int nr_pages); static void obj_cgroup_release(struct percpu_ref *ref) { @@ -163,8 +166,16 @@ static void obj_cgroup_release(struct percpu_ref *ref) WARN_ON_ONCE(nr_bytes & (PAGE_SIZE - 1)); nr_pages = nr_bytes >> PAGE_SHIFT; - if (nr_pages) - obj_cgroup_uncharge_pages(objcg, nr_pages); + if (nr_pages) { + struct mem_cgroup *memcg; + + memcg = get_mem_cgroup_from_objcg(objcg); + mod_memcg_state(memcg, MEMCG_KMEM, -nr_pages); + memcg1_account_kmem(memcg, -nr_pages); + if (!mem_cgroup_is_root(memcg)) + memcg_uncharge(memcg, nr_pages); + mem_cgroup_put(memcg); + } spin_lock_irqsave(&objcg_lock, flags); list_del(&objcg->list); @@ -277,6 +288,7 @@ ino_t page_cgroup_ino(struct page *page) rcu_read_unlock(); return ino; } +EXPORT_SYMBOL_GPL(page_cgroup_ino); /* Subset of node_stat_item for memcg stats */ static const unsigned int memcg_node_stat_items[] = { @@ -315,6 +327,7 @@ static const unsigned int memcg_node_stat_items[] = { PGDEMOTE_KSWAPD, PGDEMOTE_DIRECT, PGDEMOTE_KHUGEPAGED, + PGDEMOTE_PROACTIVE, #ifdef CONFIG_HUGETLB_PAGE NR_HUGETLB, #endif @@ -431,9 +444,11 @@ static const unsigned int memcg_vm_event_stat[] = { PGSCAN_KSWAPD, PGSCAN_DIRECT, PGSCAN_KHUGEPAGED, + PGSCAN_PROACTIVE, PGSTEAL_KSWAPD, PGSTEAL_DIRECT, PGSTEAL_KHUGEPAGED, + PGSTEAL_PROACTIVE, PGFAULT, PGMAJFAULT, PGREFILL, @@ -489,8 +504,8 @@ struct memcg_vmstats_percpu { unsigned int stats_updates; /* Cached pointers for fast iteration in memcg_rstat_updated() */ - struct memcg_vmstats_percpu *parent; - struct memcg_vmstats *vmstats; + struct memcg_vmstats_percpu __percpu *parent_pcpu; + struct memcg_vmstats *vmstats; /* The above should fit a single cacheline for memcg_rstat_updated() */ @@ -517,7 +532,7 @@ struct memcg_vmstats { unsigned long events_pending[NR_MEMCG_EVENTS]; /* Stats updates since the last flush */ - atomic64_t stats_updates; + atomic_t stats_updates; }; /* @@ -541,60 +556,41 @@ static u64 flush_last_time; #define FLUSH_TIME (2UL*HZ) -/* - * Accessors to ensure that preemption is disabled on PREEMPT_RT because it can - * not rely on this as part of an acquired spinlock_t lock. These functions are - * never used in hardirq context on PREEMPT_RT and therefore disabling preemtion - * is sufficient. - */ -static void memcg_stats_lock(void) -{ - preempt_disable_nested(); - VM_WARN_ON_IRQS_ENABLED(); -} - -static void __memcg_stats_lock(void) -{ - preempt_disable_nested(); -} - -static void memcg_stats_unlock(void) -{ - preempt_enable_nested(); -} - - static bool memcg_vmstats_needs_flush(struct memcg_vmstats *vmstats) { - return atomic64_read(&vmstats->stats_updates) > + return atomic_read(&vmstats->stats_updates) > MEMCG_CHARGE_BATCH * num_online_cpus(); } -static inline void memcg_rstat_updated(struct mem_cgroup *memcg, int val) +static inline void memcg_rstat_updated(struct mem_cgroup *memcg, int val, + int cpu) { + struct memcg_vmstats_percpu __percpu *statc_pcpu; struct memcg_vmstats_percpu *statc; - int cpu = smp_processor_id(); unsigned int stats_updates; if (!val) return; - cgroup_rstat_updated(memcg->css.cgroup, cpu); - statc = this_cpu_ptr(memcg->vmstats_percpu); - for (; statc; statc = statc->parent) { - stats_updates = READ_ONCE(statc->stats_updates) + abs(val); - WRITE_ONCE(statc->stats_updates, stats_updates); + css_rstat_updated(&memcg->css, cpu); + statc_pcpu = memcg->vmstats_percpu; + for (; statc_pcpu; statc_pcpu = statc->parent_pcpu) { + statc = this_cpu_ptr(statc_pcpu); + /* + * If @memcg is already flushable then all its ancestors are + * flushable as well and also there is no need to increase + * stats_updates. + */ + if (memcg_vmstats_needs_flush(statc->vmstats)) + break; + + stats_updates = this_cpu_add_return(statc_pcpu->stats_updates, + abs(val)); if (stats_updates < MEMCG_CHARGE_BATCH) continue; - /* - * If @memcg is already flush-able, increasing stats_updates is - * redundant. Avoid the overhead of the atomic update. - */ - if (!memcg_vmstats_needs_flush(statc->vmstats)) - atomic64_add(stats_updates, - &statc->vmstats->stats_updates); - WRITE_ONCE(statc->stats_updates, 0); + stats_updates = this_cpu_xchg(statc_pcpu->stats_updates, 0); + atomic_add(stats_updates, &statc->vmstats->stats_updates); } } @@ -602,7 +598,7 @@ static void __mem_cgroup_flush_stats(struct mem_cgroup *memcg, bool force) { bool needs_flush = memcg_vmstats_needs_flush(memcg->vmstats); - trace_memcg_flush_stats(memcg, atomic64_read(&memcg->vmstats->stats_updates), + trace_memcg_flush_stats(memcg, atomic_read(&memcg->vmstats->stats_updates), force, needs_flush); if (!force && !needs_flush) @@ -611,7 +607,7 @@ static void __mem_cgroup_flush_stats(struct mem_cgroup *memcg, bool force) if (mem_cgroup_is_root(memcg)) WRITE_ONCE(flush_last_time, jiffies_64); - cgroup_rstat_flush(memcg->css.cgroup); + css_rstat_flush(&memcg->css); } /* @@ -684,15 +680,16 @@ static int memcg_state_val_in_pages(int idx, int val) } /** - * __mod_memcg_state - update cgroup memory statistics + * mod_memcg_state - update cgroup memory statistics * @memcg: the memory cgroup * @idx: the stat item - can be enum memcg_stat_item or enum node_stat_item * @val: delta to add to the counter, can be negative */ -void __mod_memcg_state(struct mem_cgroup *memcg, enum memcg_stat_item idx, +void mod_memcg_state(struct mem_cgroup *memcg, enum memcg_stat_item idx, int val) { int i = memcg_stats_index(idx); + int cpu; if (mem_cgroup_disabled()) return; @@ -700,12 +697,17 @@ void __mod_memcg_state(struct mem_cgroup *memcg, enum memcg_stat_item idx, if (WARN_ONCE(BAD_STAT_IDX(i), "%s: missing stat item %d\n", __func__, idx)) return; - __this_cpu_add(memcg->vmstats_percpu->state[i], val); + cpu = get_cpu(); + + this_cpu_add(memcg->vmstats_percpu->state[i], val); val = memcg_state_val_in_pages(idx, val); - memcg_rstat_updated(memcg, val); + memcg_rstat_updated(memcg, val, cpu); trace_mod_memcg_state(memcg, idx, val); + + put_cpu(); } +#ifdef CONFIG_MEMCG_V1 /* idx can be of type enum memcg_stat_item or node_stat_item. */ unsigned long memcg_page_state_local(struct mem_cgroup *memcg, int idx) { @@ -722,14 +724,16 @@ unsigned long memcg_page_state_local(struct mem_cgroup *memcg, int idx) #endif return x; } +#endif -static void __mod_memcg_lruvec_state(struct lruvec *lruvec, +static void mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, int val) { struct mem_cgroup_per_node *pn; struct mem_cgroup *memcg; int i = memcg_stats_index(idx); + int cpu; if (WARN_ONCE(BAD_STAT_IDX(i), "%s: missing stat item %d\n", __func__, idx)) return; @@ -737,39 +741,23 @@ static void __mod_memcg_lruvec_state(struct lruvec *lruvec, pn = container_of(lruvec, struct mem_cgroup_per_node, lruvec); memcg = pn->memcg; - /* - * The caller from rmap relies on disabled preemption because they never - * update their counter from in-interrupt context. For these two - * counters we check that the update is never performed from an - * interrupt context while other caller need to have disabled interrupt. - */ - __memcg_stats_lock(); - if (IS_ENABLED(CONFIG_DEBUG_VM)) { - switch (idx) { - case NR_ANON_MAPPED: - case NR_FILE_MAPPED: - case NR_ANON_THPS: - WARN_ON_ONCE(!in_task()); - break; - default: - VM_WARN_ON_IRQS_ENABLED(); - } - } + cpu = get_cpu(); /* Update memcg */ - __this_cpu_add(memcg->vmstats_percpu->state[i], val); + this_cpu_add(memcg->vmstats_percpu->state[i], val); /* Update lruvec */ - __this_cpu_add(pn->lruvec_stats_percpu->state[i], val); + this_cpu_add(pn->lruvec_stats_percpu->state[i], val); val = memcg_state_val_in_pages(idx, val); - memcg_rstat_updated(memcg, val); + memcg_rstat_updated(memcg, val, cpu); trace_mod_memcg_lruvec_state(memcg, idx, val); - memcg_stats_unlock(); + + put_cpu(); } /** - * __mod_lruvec_state - update lruvec memory statistics + * mod_lruvec_state - update lruvec memory statistics * @lruvec: the lruvec * @idx: the stat item * @val: delta to add to the counter, can be negative @@ -778,18 +766,18 @@ static void __mod_memcg_lruvec_state(struct lruvec *lruvec, * function updates the all three counters that are affected by a * change of state at this level: per-node, per-cgroup, per-lruvec. */ -void __mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, +void mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, int val) { /* Update node */ - __mod_node_page_state(lruvec_pgdat(lruvec), idx, val); + mod_node_page_state(lruvec_pgdat(lruvec), idx, val); /* Update memcg and lruvec */ if (!mem_cgroup_disabled()) - __mod_memcg_lruvec_state(lruvec, idx, val); + mod_memcg_lruvec_state(lruvec, idx, val); } -void __lruvec_stat_mod_folio(struct folio *folio, enum node_stat_item idx, +void lruvec_stat_mod_folio(struct folio *folio, enum node_stat_item idx, int val) { struct mem_cgroup *memcg; @@ -801,17 +789,17 @@ void __lruvec_stat_mod_folio(struct folio *folio, enum node_stat_item idx, /* Untracked pages have no memcg, no lruvec. Update only the node */ if (!memcg) { rcu_read_unlock(); - __mod_node_page_state(pgdat, idx, val); + mod_node_page_state(pgdat, idx, val); return; } lruvec = mem_cgroup_lruvec(memcg, pgdat); - __mod_lruvec_state(lruvec, idx, val); + mod_lruvec_state(lruvec, idx, val); rcu_read_unlock(); } -EXPORT_SYMBOL(__lruvec_stat_mod_folio); +EXPORT_SYMBOL(lruvec_stat_mod_folio); -void __mod_lruvec_kmem_state(void *p, enum node_stat_item idx, int val) +void mod_lruvec_kmem_state(void *p, enum node_stat_item idx, int val) { pg_data_t *pgdat = page_pgdat(virt_to_page(p)); struct mem_cgroup *memcg; @@ -827,24 +815,25 @@ void __mod_lruvec_kmem_state(void *p, enum node_stat_item idx, int val) * vmstats to keep it correct for the root memcg. */ if (!memcg) { - __mod_node_page_state(pgdat, idx, val); + mod_node_page_state(pgdat, idx, val); } else { lruvec = mem_cgroup_lruvec(memcg, pgdat); - __mod_lruvec_state(lruvec, idx, val); + mod_lruvec_state(lruvec, idx, val); } rcu_read_unlock(); } /** - * __count_memcg_events - account VM events in a cgroup + * count_memcg_events - account VM events in a cgroup * @memcg: the memory cgroup * @idx: the event item * @count: the number of events that occurred */ -void __count_memcg_events(struct mem_cgroup *memcg, enum vm_event_item idx, +void count_memcg_events(struct mem_cgroup *memcg, enum vm_event_item idx, unsigned long count) { int i = memcg_events_index(idx); + int cpu; if (mem_cgroup_disabled()) return; @@ -852,11 +841,13 @@ void __count_memcg_events(struct mem_cgroup *memcg, enum vm_event_item idx, if (WARN_ONCE(BAD_STAT_IDX(i), "%s: missing stat item %d\n", __func__, idx)) return; - memcg_stats_lock(); - __this_cpu_add(memcg->vmstats_percpu->events[i], count); - memcg_rstat_updated(memcg, count); + cpu = get_cpu(); + + this_cpu_add(memcg->vmstats_percpu->events[i], count); + memcg_rstat_updated(memcg, count, cpu); trace_count_memcg_events(memcg, idx, count); - memcg_stats_unlock(); + + put_cpu(); } unsigned long memcg_events(struct mem_cgroup *memcg, int event) @@ -869,6 +860,7 @@ unsigned long memcg_events(struct mem_cgroup *memcg, int event) return READ_ONCE(memcg->vmstats->events[i]); } +#ifdef CONFIG_MEMCG_V1 unsigned long memcg_events_local(struct mem_cgroup *memcg, int event) { int i = memcg_events_index(event); @@ -878,6 +870,7 @@ unsigned long memcg_events_local(struct mem_cgroup *memcg, int event) return READ_ONCE(memcg->vmstats->events_local[i]); } +#endif struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p) { @@ -1169,8 +1162,11 @@ void mem_cgroup_scan_tasks(struct mem_cgroup *memcg, struct task_struct *task; css_task_iter_start(&iter->css, CSS_TASK_ITER_PROCS, &it); - while (!ret && (task = css_task_iter_next(&it))) + while (!ret && (task = css_task_iter_next(&it))) { ret = fn(task, arg); + /* Avoid potential softlockup warning */ + cond_resched(); + } css_task_iter_end(&it); if (ret) { mem_cgroup_iter_break(memcg, iter); @@ -1385,6 +1381,7 @@ static const struct memory_stat memory_stats[] = { { "pgdemote_kswapd", PGDEMOTE_KSWAPD }, { "pgdemote_direct", PGDEMOTE_DIRECT }, { "pgdemote_khugepaged", PGDEMOTE_KHUGEPAGED }, + { "pgdemote_proactive", PGDEMOTE_PROACTIVE }, #ifdef CONFIG_NUMA_BALANCING { "pgpromote_success", PGPROMOTE_SUCCESS }, #endif @@ -1427,6 +1424,7 @@ static int memcg_page_state_output_unit(int item) case PGDEMOTE_KSWAPD: case PGDEMOTE_DIRECT: case PGDEMOTE_KHUGEPAGED: + case PGDEMOTE_PROACTIVE: #ifdef CONFIG_NUMA_BALANCING case PGPROMOTE_SUCCESS: #endif @@ -1442,11 +1440,25 @@ unsigned long memcg_page_state_output(struct mem_cgroup *memcg, int item) memcg_page_state_output_unit(item); } +#ifdef CONFIG_MEMCG_V1 unsigned long memcg_page_state_local_output(struct mem_cgroup *memcg, int item) { return memcg_page_state_local(memcg, item) * memcg_page_state_output_unit(item); } +#endif + +#ifdef CONFIG_HUGETLB_PAGE +static bool memcg_accounts_hugetlb(void) +{ + return cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING; +} +#else /* CONFIG_HUGETLB_PAGE */ +static bool memcg_accounts_hugetlb(void) +{ + return false; +} +#endif /* CONFIG_HUGETLB_PAGE */ static void memcg_stat_format(struct mem_cgroup *memcg, struct seq_buf *s) { @@ -1469,7 +1481,7 @@ static void memcg_stat_format(struct mem_cgroup *memcg, struct seq_buf *s) #ifdef CONFIG_HUGETLB_PAGE if (unlikely(memory_stats[i].idx == NR_HUGETLB) && - !(cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING)) + !memcg_accounts_hugetlb()) continue; #endif size = memcg_page_state_output(memcg, memory_stats[i].idx); @@ -1486,10 +1498,12 @@ static void memcg_stat_format(struct mem_cgroup *memcg, struct seq_buf *s) seq_buf_printf(s, "pgscan %lu\n", memcg_events(memcg, PGSCAN_KSWAPD) + memcg_events(memcg, PGSCAN_DIRECT) + + memcg_events(memcg, PGSCAN_PROACTIVE) + memcg_events(memcg, PGSCAN_KHUGEPAGED)); seq_buf_printf(s, "pgsteal %lu\n", memcg_events(memcg, PGSTEAL_KSWAPD) + memcg_events(memcg, PGSTEAL_DIRECT) + + memcg_events(memcg, PGSTEAL_PROACTIVE) + memcg_events(memcg, PGSTEAL_KHUGEPAGED)); for (i = 0; i < ARRAY_SIZE(memcg_vm_event_stat); i++) { @@ -1549,16 +1563,23 @@ void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg) /* Use static buffer, for the caller is holding oom_lock. */ static char buf[SEQ_BUF_SIZE]; struct seq_buf s; + unsigned long memory_failcnt; lockdep_assert_held(&oom_lock); + if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) + memory_failcnt = atomic_long_read(&memcg->memory_events[MEMCG_MAX]); + else + memory_failcnt = memcg->memory.failcnt; + pr_info("memory: usage %llukB, limit %llukB, failcnt %lu\n", K((u64)page_counter_read(&memcg->memory)), - K((u64)READ_ONCE(memcg->memory.max)), memcg->memory.failcnt); + K((u64)READ_ONCE(memcg->memory.max)), memory_failcnt); if (cgroup_subsys_on_dfl(memory_cgrp_subsys)) pr_info("swap: usage %llukB, limit %llukB, failcnt %lu\n", K((u64)page_counter_read(&memcg->swap)), - K((u64)READ_ONCE(memcg->swap.max)), memcg->swap.failcnt); + K((u64)READ_ONCE(memcg->swap.max)), + atomic_long_read(&memcg->memory_events[MEMCG_SWAP_MAX])); #ifdef CONFIG_MEMCG_V1 else { pr_info("memory+swap: usage %llukB, limit %llukB, failcnt %lu\n", @@ -1605,6 +1626,37 @@ unsigned long mem_cgroup_size(struct mem_cgroup *memcg) return page_counter_read(&memcg->memory); } +void __memcg_memory_event(struct mem_cgroup *memcg, + enum memcg_memory_event event, bool allow_spinning) +{ + bool swap_event = event == MEMCG_SWAP_HIGH || event == MEMCG_SWAP_MAX || + event == MEMCG_SWAP_FAIL; + + /* For now only MEMCG_MAX can happen with !allow_spinning context. */ + VM_WARN_ON_ONCE(!allow_spinning && event != MEMCG_MAX); + + atomic_long_inc(&memcg->memory_events_local[event]); + if (!swap_event && allow_spinning) + cgroup_file_notify(&memcg->events_local_file); + + do { + atomic_long_inc(&memcg->memory_events[event]); + if (allow_spinning) { + if (swap_event) + cgroup_file_notify(&memcg->swap_events_file); + else + cgroup_file_notify(&memcg->events_file); + } + + if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) + break; + if (cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_LOCAL_EVENTS) + break; + } while ((memcg = parent_mem_cgroup(memcg)) && + !mem_cgroup_is_root(memcg)); +} +EXPORT_SYMBOL_GPL(__memcg_memory_event); + static bool mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask, int order) { @@ -1627,7 +1679,7 @@ static bool mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask, * A few threads which were not waiting at mutex_lock_killable() can * fail to bail out. Therefore, check again after holding oom_lock. */ - ret = task_is_dying() || out_of_memory(&oc); + ret = out_of_memory(&oc); unlock: mutex_unlock(&oom_lock); @@ -1721,28 +1773,45 @@ void mem_cgroup_print_oom_group(struct mem_cgroup *memcg) pr_cont(" are going to be killed due to memory.oom.group set\n"); } +/* + * The value of NR_MEMCG_STOCK is selected to keep the cached memcgs and their + * nr_pages in a single cacheline. This may change in future. + */ +#define NR_MEMCG_STOCK 7 +#define FLUSHING_CACHED_CHARGE 0 struct memcg_stock_pcp { - local_lock_t stock_lock; - struct mem_cgroup *cached; /* this never be root cgroup */ - unsigned int nr_pages; + local_trylock_t lock; + uint8_t nr_pages[NR_MEMCG_STOCK]; + struct mem_cgroup *cached[NR_MEMCG_STOCK]; + + struct work_struct work; + unsigned long flags; +}; +static DEFINE_PER_CPU_ALIGNED(struct memcg_stock_pcp, memcg_stock) = { + .lock = INIT_LOCAL_TRYLOCK(lock), +}; + +struct obj_stock_pcp { + local_trylock_t lock; + unsigned int nr_bytes; struct obj_cgroup *cached_objcg; struct pglist_data *cached_pgdat; - unsigned int nr_bytes; int nr_slab_reclaimable_b; int nr_slab_unreclaimable_b; struct work_struct work; unsigned long flags; -#define FLUSHING_CACHED_CHARGE 0 }; -static DEFINE_PER_CPU(struct memcg_stock_pcp, memcg_stock) = { - .stock_lock = INIT_LOCAL_LOCK(stock_lock), + +static DEFINE_PER_CPU_ALIGNED(struct obj_stock_pcp, obj_stock) = { + .lock = INIT_LOCAL_TRYLOCK(lock), }; + static DEFINE_MUTEX(percpu_charge_mutex); -static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock); -static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, +static void drain_obj_stock(struct obj_stock_pcp *stock); +static bool obj_stock_flush_required(struct obj_stock_pcp *stock, struct mem_cgroup *root_memcg); /** @@ -1750,110 +1819,188 @@ static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, * @memcg: memcg to consume from. * @nr_pages: how many pages to charge. * - * The charges will only happen if @memcg matches the current cpu's memcg - * stock, and at least @nr_pages are available in that stock. Failure to - * service an allocation will refill the stock. + * Consume the cached charge if enough nr_pages are present otherwise return + * failure. Also return failure for charge request larger than + * MEMCG_CHARGE_BATCH or if the local lock is already taken. * * returns true if successful, false otherwise. */ static bool consume_stock(struct mem_cgroup *memcg, unsigned int nr_pages) { struct memcg_stock_pcp *stock; - unsigned int stock_pages; - unsigned long flags; + uint8_t stock_pages; bool ret = false; + int i; - if (nr_pages > MEMCG_CHARGE_BATCH) + if (nr_pages > MEMCG_CHARGE_BATCH || + !local_trylock(&memcg_stock.lock)) return ret; - local_lock_irqsave(&memcg_stock.stock_lock, flags); - stock = this_cpu_ptr(&memcg_stock); - stock_pages = READ_ONCE(stock->nr_pages); - if (memcg == READ_ONCE(stock->cached) && stock_pages >= nr_pages) { - WRITE_ONCE(stock->nr_pages, stock_pages - nr_pages); - ret = true; + + for (i = 0; i < NR_MEMCG_STOCK; ++i) { + if (memcg != READ_ONCE(stock->cached[i])) + continue; + + stock_pages = READ_ONCE(stock->nr_pages[i]); + if (stock_pages >= nr_pages) { + WRITE_ONCE(stock->nr_pages[i], stock_pages - nr_pages); + ret = true; + } + break; } - local_unlock_irqrestore(&memcg_stock.stock_lock, flags); + local_unlock(&memcg_stock.lock); return ret; } +static void memcg_uncharge(struct mem_cgroup *memcg, unsigned int nr_pages) +{ + page_counter_uncharge(&memcg->memory, nr_pages); + if (do_memsw_account()) + page_counter_uncharge(&memcg->memsw, nr_pages); +} + /* * Returns stocks cached in percpu and reset cached information. */ -static void drain_stock(struct memcg_stock_pcp *stock) +static void drain_stock(struct memcg_stock_pcp *stock, int i) { - unsigned int stock_pages = READ_ONCE(stock->nr_pages); - struct mem_cgroup *old = READ_ONCE(stock->cached); + struct mem_cgroup *old = READ_ONCE(stock->cached[i]); + uint8_t stock_pages; if (!old) return; + stock_pages = READ_ONCE(stock->nr_pages[i]); if (stock_pages) { - page_counter_uncharge(&old->memory, stock_pages); - if (do_memsw_account()) - page_counter_uncharge(&old->memsw, stock_pages); - - WRITE_ONCE(stock->nr_pages, 0); + memcg_uncharge(old, stock_pages); + WRITE_ONCE(stock->nr_pages[i], 0); } css_put(&old->css); - WRITE_ONCE(stock->cached, NULL); + WRITE_ONCE(stock->cached[i], NULL); } -static void drain_local_stock(struct work_struct *dummy) +static void drain_stock_fully(struct memcg_stock_pcp *stock) +{ + int i; + + for (i = 0; i < NR_MEMCG_STOCK; ++i) + drain_stock(stock, i); +} + +static void drain_local_memcg_stock(struct work_struct *dummy) { struct memcg_stock_pcp *stock; - struct obj_cgroup *old = NULL; - unsigned long flags; - /* - * The only protection from cpu hotplug (memcg_hotplug_cpu_dead) vs. - * drain_stock races is that we always operate on local CPU stock - * here with IRQ disabled - */ - local_lock_irqsave(&memcg_stock.stock_lock, flags); + if (WARN_ONCE(!in_task(), "drain in non-task context")) + return; + + local_lock(&memcg_stock.lock); stock = this_cpu_ptr(&memcg_stock); - old = drain_obj_stock(stock); - drain_stock(stock); + drain_stock_fully(stock); clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags); - local_unlock_irqrestore(&memcg_stock.stock_lock, flags); - obj_cgroup_put(old); + local_unlock(&memcg_stock.lock); } -/* - * Cache charges(val) to local per_cpu area. - * This will be consumed by consume_stock() function, later. - */ -static void __refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) +static void drain_local_obj_stock(struct work_struct *dummy) +{ + struct obj_stock_pcp *stock; + + if (WARN_ONCE(!in_task(), "drain in non-task context")) + return; + + local_lock(&obj_stock.lock); + + stock = this_cpu_ptr(&obj_stock); + drain_obj_stock(stock); + clear_bit(FLUSHING_CACHED_CHARGE, &stock->flags); + + local_unlock(&obj_stock.lock); +} + +static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) { struct memcg_stock_pcp *stock; - unsigned int stock_pages; + struct mem_cgroup *cached; + uint8_t stock_pages; + bool success = false; + int empty_slot = -1; + int i; + + /* + * For now limit MEMCG_CHARGE_BATCH to 127 and less. In future if we + * decide to increase it more than 127 then we will need more careful + * handling of nr_pages[] in struct memcg_stock_pcp. + */ + BUILD_BUG_ON(MEMCG_CHARGE_BATCH > S8_MAX); + + VM_WARN_ON_ONCE(mem_cgroup_is_root(memcg)); + + if (nr_pages > MEMCG_CHARGE_BATCH || + !local_trylock(&memcg_stock.lock)) { + /* + * In case of larger than batch refill or unlikely failure to + * lock the percpu memcg_stock.lock, uncharge memcg directly. + */ + memcg_uncharge(memcg, nr_pages); + return; + } stock = this_cpu_ptr(&memcg_stock); - if (READ_ONCE(stock->cached) != memcg) { /* reset if necessary */ - drain_stock(stock); + for (i = 0; i < NR_MEMCG_STOCK; ++i) { + cached = READ_ONCE(stock->cached[i]); + if (!cached && empty_slot == -1) + empty_slot = i; + if (memcg == READ_ONCE(stock->cached[i])) { + stock_pages = READ_ONCE(stock->nr_pages[i]) + nr_pages; + WRITE_ONCE(stock->nr_pages[i], stock_pages); + if (stock_pages > MEMCG_CHARGE_BATCH) + drain_stock(stock, i); + success = true; + break; + } + } + + if (!success) { + i = empty_slot; + if (i == -1) { + i = get_random_u32_below(NR_MEMCG_STOCK); + drain_stock(stock, i); + } css_get(&memcg->css); - WRITE_ONCE(stock->cached, memcg); + WRITE_ONCE(stock->cached[i], memcg); + WRITE_ONCE(stock->nr_pages[i], nr_pages); } - stock_pages = READ_ONCE(stock->nr_pages) + nr_pages; - WRITE_ONCE(stock->nr_pages, stock_pages); - if (stock_pages > MEMCG_CHARGE_BATCH) - drain_stock(stock); + local_unlock(&memcg_stock.lock); } -static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) +static bool is_memcg_drain_needed(struct memcg_stock_pcp *stock, + struct mem_cgroup *root_memcg) { - unsigned long flags; + struct mem_cgroup *memcg; + bool flush = false; + int i; + + rcu_read_lock(); + for (i = 0; i < NR_MEMCG_STOCK; ++i) { + memcg = READ_ONCE(stock->cached[i]); + if (!memcg) + continue; - local_lock_irqsave(&memcg_stock.stock_lock, flags); - __refill_stock(memcg, nr_pages); - local_unlock_irqrestore(&memcg_stock.stock_lock, flags); + if (READ_ONCE(stock->nr_pages[i]) && + mem_cgroup_is_descendant(memcg, root_memcg)) { + flush = true; + break; + } + } + rcu_read_unlock(); + return flush; } /* @@ -1876,25 +2023,27 @@ void drain_all_stock(struct mem_cgroup *root_memcg) migrate_disable(); curcpu = smp_processor_id(); for_each_online_cpu(cpu) { - struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); - struct mem_cgroup *memcg; - bool flush = false; + struct memcg_stock_pcp *memcg_st = &per_cpu(memcg_stock, cpu); + struct obj_stock_pcp *obj_st = &per_cpu(obj_stock, cpu); - rcu_read_lock(); - memcg = READ_ONCE(stock->cached); - if (memcg && READ_ONCE(stock->nr_pages) && - mem_cgroup_is_descendant(memcg, root_memcg)) - flush = true; - else if (obj_stock_flush_required(stock, root_memcg)) - flush = true; - rcu_read_unlock(); + if (!test_bit(FLUSHING_CACHED_CHARGE, &memcg_st->flags) && + is_memcg_drain_needed(memcg_st, root_memcg) && + !test_and_set_bit(FLUSHING_CACHED_CHARGE, + &memcg_st->flags)) { + if (cpu == curcpu) + drain_local_memcg_stock(&memcg_st->work); + else if (!cpu_is_isolated(cpu)) + schedule_work_on(cpu, &memcg_st->work); + } - if (flush && - !test_and_set_bit(FLUSHING_CACHED_CHARGE, &stock->flags)) { + if (!test_bit(FLUSHING_CACHED_CHARGE, &obj_st->flags) && + obj_stock_flush_required(obj_st, root_memcg) && + !test_and_set_bit(FLUSHING_CACHED_CHARGE, + &obj_st->flags)) { if (cpu == curcpu) - drain_local_stock(&stock->work); + drain_local_obj_stock(&obj_st->work); else if (!cpu_is_isolated(cpu)) - schedule_work_on(cpu, &stock->work); + schedule_work_on(cpu, &obj_st->work); } } migrate_enable(); @@ -1903,10 +2052,9 @@ void drain_all_stock(struct mem_cgroup *root_memcg) static int memcg_hotplug_cpu_dead(unsigned int cpu) { - struct memcg_stock_pcp *stock; - - stock = &per_cpu(memcg_stock, cpu); - drain_stock(stock); + /* no need for the local lock */ + drain_obj_stock(&per_cpu(obj_stock, cpu)); + drain_stock_fully(&per_cpu(memcg_stock, cpu)); return 0; } @@ -2088,7 +2236,7 @@ static unsigned long calculate_high_delay(struct mem_cgroup *memcg, * try_charge() (context permitting), as well as from the userland * return path where reclaim is always able to block. */ -void mem_cgroup_handle_over_high(gfp_t gfp_mask) +void __mem_cgroup_handle_over_high(gfp_t gfp_mask) { unsigned long penalty_jiffies; unsigned long pflags; @@ -2098,9 +2246,6 @@ void mem_cgroup_handle_over_high(gfp_t gfp_mask) struct mem_cgroup *memcg; bool in_retry = false; - if (likely(!nr_pages)) - return; - memcg = get_mem_cgroup_from_mm(current->mm); current->memcg_nr_pages_over_high = 0; @@ -2181,8 +2326,8 @@ out: css_put(&memcg->css); } -int try_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp_mask, - unsigned int nr_pages) +static int try_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp_mask, + unsigned int nr_pages) { unsigned int batch = max(MEMCG_CHARGE_BATCH, nr_pages); int nr_retries = MAX_RECLAIM_RETRIES; @@ -2194,11 +2339,16 @@ int try_charge_memcg(struct mem_cgroup *memcg, gfp_t gfp_mask, bool drained = false; bool raised_max_event = false; unsigned long pflags; + bool allow_spinning = gfpflags_allow_spinning(gfp_mask); retry: if (consume_stock(memcg, nr_pages)) return 0; + if (!allow_spinning) + /* Avoid the refill and flush of the older stock */ + batch = nr_pages; + if (!do_memsw_account() || page_counter_try_charge(&memcg->memsw, batch, &counter)) { if (page_counter_try_charge(&memcg->memory, batch, &counter)) @@ -2231,7 +2381,7 @@ retry: if (!gfpflags_allow_blocking(gfp_mask)) goto nomem; - memcg_memory_event(mem_over_limit, MEMCG_MAX); + __memcg_memory_event(mem_over_limit, MEMCG_MAX, allow_spinning); raised_max_event = true; psi_memstall_enter(&pflags); @@ -2298,7 +2448,7 @@ force: * a MEMCG_MAX event. */ if (!raised_max_event) - memcg_memory_event(mem_over_limit, MEMCG_MAX); + __memcg_memory_event(mem_over_limit, MEMCG_MAX, allow_spinning); /* * The allocation either can't fail or will lead to more memory @@ -2367,23 +2517,17 @@ done_restock: if (current->memcg_nr_pages_over_high > MEMCG_CHARGE_BATCH && !(current->flags & PF_MEMALLOC) && gfpflags_allow_blocking(gfp_mask)) - mem_cgroup_handle_over_high(gfp_mask); + __mem_cgroup_handle_over_high(gfp_mask); return 0; } -/** - * mem_cgroup_cancel_charge() - cancel an uncommitted try_charge() call. - * @memcg: memcg previously charged. - * @nr_pages: number of pages previously charged. - */ -void mem_cgroup_cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages) +static inline int try_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, + unsigned int nr_pages) { if (mem_cgroup_is_root(memcg)) - return; + return 0; - page_counter_uncharge(&memcg->memory, nr_pages); - if (do_memsw_account()) - page_counter_uncharge(&memcg->memsw, nr_pages); + return try_charge_memcg(memcg, gfp_mask, nr_pages); } static void commit_charge(struct folio *folio, struct mem_cgroup *memcg) @@ -2399,65 +2543,71 @@ static void commit_charge(struct folio *folio, struct mem_cgroup *memcg) folio->memcg_data = (unsigned long)memcg; } -/** - * mem_cgroup_commit_charge - commit a previously successful try_charge(). - * @folio: folio to commit the charge to. - * @memcg: memcg previously charged. - */ -void mem_cgroup_commit_charge(struct folio *folio, struct mem_cgroup *memcg) +#ifdef CONFIG_MEMCG_NMI_SAFETY_REQUIRES_ATOMIC +static inline void account_slab_nmi_safe(struct mem_cgroup *memcg, + struct pglist_data *pgdat, + enum node_stat_item idx, int nr) { - css_get(&memcg->css); - commit_charge(folio, memcg); - memcg1_commit_charge(folio, memcg); + struct lruvec *lruvec; + + if (likely(!in_nmi())) { + lruvec = mem_cgroup_lruvec(memcg, pgdat); + mod_memcg_lruvec_state(lruvec, idx, nr); + } else { + struct mem_cgroup_per_node *pn = memcg->nodeinfo[pgdat->node_id]; + + /* preemption is disabled in_nmi(). */ + css_rstat_updated(&memcg->css, smp_processor_id()); + if (idx == NR_SLAB_RECLAIMABLE_B) + atomic_add(nr, &pn->slab_reclaimable); + else + atomic_add(nr, &pn->slab_unreclaimable); + } } +#else +static inline void account_slab_nmi_safe(struct mem_cgroup *memcg, + struct pglist_data *pgdat, + enum node_stat_item idx, int nr) +{ + struct lruvec *lruvec; + + lruvec = mem_cgroup_lruvec(memcg, pgdat); + mod_memcg_lruvec_state(lruvec, idx, nr); +} +#endif -static inline void __mod_objcg_mlstate(struct obj_cgroup *objcg, +static inline void mod_objcg_mlstate(struct obj_cgroup *objcg, struct pglist_data *pgdat, enum node_stat_item idx, int nr) { struct mem_cgroup *memcg; - struct lruvec *lruvec; rcu_read_lock(); memcg = obj_cgroup_memcg(objcg); - lruvec = mem_cgroup_lruvec(memcg, pgdat); - __mod_memcg_lruvec_state(lruvec, idx, nr); + account_slab_nmi_safe(memcg, pgdat, idx, nr); rcu_read_unlock(); } static __always_inline -struct mem_cgroup *mem_cgroup_from_obj_folio(struct folio *folio, void *p) +struct mem_cgroup *mem_cgroup_from_obj_slab(struct slab *slab, void *p) { /* * Slab objects are accounted individually, not per-page. * Memcg membership data for each individual object is saved in * slab->obj_exts. */ - if (folio_test_slab(folio)) { - struct slabobj_ext *obj_exts; - struct slab *slab; - unsigned int off; - - slab = folio_slab(folio); - obj_exts = slab_obj_exts(slab); - if (!obj_exts) - return NULL; - - off = obj_to_index(slab->slab_cache, slab, p); - if (obj_exts[off].objcg) - return obj_cgroup_memcg(obj_exts[off].objcg); + struct slabobj_ext *obj_exts; + unsigned int off; + obj_exts = slab_obj_exts(slab); + if (!obj_exts) return NULL; - } - /* - * folio_memcg_check() is used here, because in theory we can encounter - * a folio where the slab flag has been cleared already, but - * slab->obj_exts has not been freed yet - * folio_memcg_check() will guarantee that a proper memory - * cgroup pointer or NULL will be returned. - */ - return folio_memcg_check(folio); + off = obj_to_index(slab->slab_cache, slab, p); + if (obj_exts[off].objcg) + return obj_cgroup_memcg(obj_exts[off].objcg); + + return NULL; } /* @@ -2471,10 +2621,15 @@ struct mem_cgroup *mem_cgroup_from_obj_folio(struct folio *folio, void *p) */ struct mem_cgroup *mem_cgroup_from_slab_obj(void *p) { + struct slab *slab; + if (mem_cgroup_disabled()) return NULL; - return mem_cgroup_from_obj_folio(virt_to_folio(p), p); + slab = virt_to_slab(p); + if (slab) + return mem_cgroup_from_obj_slab(slab, p); + return folio_memcg_check(virt_to_folio(p)); } static struct obj_cgroup *__get_obj_cgroup_from_memcg(struct mem_cgroup *memcg) @@ -2546,6 +2701,9 @@ __always_inline struct obj_cgroup *current_obj_cgroup(void) struct mem_cgroup *memcg; struct obj_cgroup *objcg; + if (IS_ENABLED(CONFIG_MEMCG_NMI_UNSAFE) && in_nmi()) + return NULL; + if (in_task()) { memcg = current->active_memcg; if (unlikely(memcg)) @@ -2608,6 +2766,24 @@ struct obj_cgroup *get_obj_cgroup_from_folio(struct folio *folio) return objcg; } +#ifdef CONFIG_MEMCG_NMI_SAFETY_REQUIRES_ATOMIC +static inline void account_kmem_nmi_safe(struct mem_cgroup *memcg, int val) +{ + if (likely(!in_nmi())) { + mod_memcg_state(memcg, MEMCG_KMEM, val); + } else { + /* preemption is disabled in_nmi(). */ + css_rstat_updated(&memcg->css, smp_processor_id()); + atomic_add(val, &memcg->kmem_stat); + } +} +#else +static inline void account_kmem_nmi_safe(struct mem_cgroup *memcg, int val) +{ + mod_memcg_state(memcg, MEMCG_KMEM, val); +} +#endif + /* * obj_cgroup_uncharge_pages: uncharge a number of kernel pages from a objcg * @objcg: object cgroup to uncharge @@ -2620,9 +2796,10 @@ static void obj_cgroup_uncharge_pages(struct obj_cgroup *objcg, memcg = get_mem_cgroup_from_objcg(objcg); - mod_memcg_state(memcg, MEMCG_KMEM, -nr_pages); + account_kmem_nmi_safe(memcg, -nr_pages); memcg1_account_kmem(memcg, -nr_pages); - refill_stock(memcg, nr_pages); + if (!mem_cgroup_is_root(memcg)) + refill_stock(memcg, nr_pages); css_put(&memcg->css); } @@ -2647,7 +2824,7 @@ static int obj_cgroup_charge_pages(struct obj_cgroup *objcg, gfp_t gfp, if (ret) goto out; - mod_memcg_state(memcg, MEMCG_KMEM, nr_pages); + account_kmem_nmi_safe(memcg, nr_pages); memcg1_account_kmem(memcg, nr_pages); out: css_put(&memcg->css); @@ -2655,6 +2832,23 @@ out: return ret; } +static struct obj_cgroup *page_objcg(const struct page *page) +{ + unsigned long memcg_data = page->memcg_data; + + if (mem_cgroup_disabled() || !memcg_data) + return NULL; + + VM_BUG_ON_PAGE((memcg_data & OBJEXTS_FLAGS_MASK) != MEMCG_DATA_KMEM, + page); + return (struct obj_cgroup *)(memcg_data - MEMCG_DATA_KMEM); +} + +static void page_set_objcg(struct page *page, const struct obj_cgroup *objcg) +{ + page->memcg_data = (unsigned long)objcg | MEMCG_DATA_KMEM; +} + /** * __memcg_kmem_charge_page: charge a kmem page to the current memory cgroup * @page: page to charge @@ -2673,8 +2867,7 @@ int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order) ret = obj_cgroup_charge_pages(objcg, gfp, 1 << order); if (!ret) { obj_cgroup_get(objcg); - page->memcg_data = (unsigned long)objcg | - MEMCG_DATA_KMEM; + page_set_objcg(page, objcg); return 0; } } @@ -2688,53 +2881,38 @@ int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order) */ void __memcg_kmem_uncharge_page(struct page *page, int order) { - struct folio *folio = page_folio(page); - struct obj_cgroup *objcg; + struct obj_cgroup *objcg = page_objcg(page); unsigned int nr_pages = 1 << order; - if (!folio_memcg_kmem(folio)) + if (!objcg) return; - objcg = __folio_objcg(folio); obj_cgroup_uncharge_pages(objcg, nr_pages); - folio->memcg_data = 0; + page->memcg_data = 0; obj_cgroup_put(objcg); } -static void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat, - enum node_stat_item idx, int nr) +static void __account_obj_stock(struct obj_cgroup *objcg, + struct obj_stock_pcp *stock, int nr, + struct pglist_data *pgdat, enum node_stat_item idx) { - struct memcg_stock_pcp *stock; - struct obj_cgroup *old = NULL; - unsigned long flags; int *bytes; - local_lock_irqsave(&memcg_stock.stock_lock, flags); - stock = this_cpu_ptr(&memcg_stock); - /* * Save vmstat data in stock and skip vmstat array update unless - * accumulating over a page of vmstat data or when pgdat or idx - * changes. + * accumulating over a page of vmstat data or when pgdat changes. */ - if (READ_ONCE(stock->cached_objcg) != objcg) { - old = drain_obj_stock(stock); - obj_cgroup_get(objcg); - stock->nr_bytes = atomic_read(&objcg->nr_charged_bytes) - ? atomic_xchg(&objcg->nr_charged_bytes, 0) : 0; - WRITE_ONCE(stock->cached_objcg, objcg); - stock->cached_pgdat = pgdat; - } else if (stock->cached_pgdat != pgdat) { + if (stock->cached_pgdat != pgdat) { /* Flush the existing cached vmstat data */ struct pglist_data *oldpg = stock->cached_pgdat; if (stock->nr_slab_reclaimable_b) { - __mod_objcg_mlstate(objcg, oldpg, NR_SLAB_RECLAIMABLE_B, + mod_objcg_mlstate(objcg, oldpg, NR_SLAB_RECLAIMABLE_B, stock->nr_slab_reclaimable_b); stock->nr_slab_reclaimable_b = 0; } if (stock->nr_slab_unreclaimable_b) { - __mod_objcg_mlstate(objcg, oldpg, NR_SLAB_UNRECLAIMABLE_B, + mod_objcg_mlstate(objcg, oldpg, NR_SLAB_UNRECLAIMABLE_B, stock->nr_slab_unreclaimable_b); stock->nr_slab_unreclaimable_b = 0; } @@ -2760,37 +2938,38 @@ static void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat, } } if (nr) - __mod_objcg_mlstate(objcg, pgdat, idx, nr); - - local_unlock_irqrestore(&memcg_stock.stock_lock, flags); - obj_cgroup_put(old); + mod_objcg_mlstate(objcg, pgdat, idx, nr); } -static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes) +static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes, + struct pglist_data *pgdat, enum node_stat_item idx) { - struct memcg_stock_pcp *stock; - unsigned long flags; + struct obj_stock_pcp *stock; bool ret = false; - local_lock_irqsave(&memcg_stock.stock_lock, flags); + if (!local_trylock(&obj_stock.lock)) + return ret; - stock = this_cpu_ptr(&memcg_stock); + stock = this_cpu_ptr(&obj_stock); if (objcg == READ_ONCE(stock->cached_objcg) && stock->nr_bytes >= nr_bytes) { stock->nr_bytes -= nr_bytes; ret = true; + + if (pgdat) + __account_obj_stock(objcg, stock, nr_bytes, pgdat, idx); } - local_unlock_irqrestore(&memcg_stock.stock_lock, flags); + local_unlock(&obj_stock.lock); return ret; } -static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock) +static void drain_obj_stock(struct obj_stock_pcp *stock) { struct obj_cgroup *old = READ_ONCE(stock->cached_objcg); if (!old) - return NULL; + return; if (stock->nr_bytes) { unsigned int nr_pages = stock->nr_bytes >> PAGE_SHIFT; @@ -2803,7 +2982,8 @@ static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock) mod_memcg_state(memcg, MEMCG_KMEM, -nr_pages); memcg1_account_kmem(memcg, -nr_pages); - __refill_stock(memcg, nr_pages); + if (!mem_cgroup_is_root(memcg)) + memcg_uncharge(memcg, nr_pages); css_put(&memcg->css); } @@ -2827,13 +3007,13 @@ static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock) */ if (stock->nr_slab_reclaimable_b || stock->nr_slab_unreclaimable_b) { if (stock->nr_slab_reclaimable_b) { - __mod_objcg_mlstate(old, stock->cached_pgdat, + mod_objcg_mlstate(old, stock->cached_pgdat, NR_SLAB_RECLAIMABLE_B, stock->nr_slab_reclaimable_b); stock->nr_slab_reclaimable_b = 0; } if (stock->nr_slab_unreclaimable_b) { - __mod_objcg_mlstate(old, stock->cached_pgdat, + mod_objcg_mlstate(old, stock->cached_pgdat, NR_SLAB_UNRECLAIMABLE_B, stock->nr_slab_unreclaimable_b); stock->nr_slab_unreclaimable_b = 0; @@ -2842,67 +3022,76 @@ static struct obj_cgroup *drain_obj_stock(struct memcg_stock_pcp *stock) } WRITE_ONCE(stock->cached_objcg, NULL); - /* - * The `old' objects needs to be released by the caller via - * obj_cgroup_put() outside of memcg_stock_pcp::stock_lock. - */ - return old; + obj_cgroup_put(old); } -static bool obj_stock_flush_required(struct memcg_stock_pcp *stock, +static bool obj_stock_flush_required(struct obj_stock_pcp *stock, struct mem_cgroup *root_memcg) { struct obj_cgroup *objcg = READ_ONCE(stock->cached_objcg); struct mem_cgroup *memcg; + bool flush = false; + rcu_read_lock(); if (objcg) { memcg = obj_cgroup_memcg(objcg); if (memcg && mem_cgroup_is_descendant(memcg, root_memcg)) - return true; + flush = true; } + rcu_read_unlock(); - return false; + return flush; } static void refill_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes, - bool allow_uncharge) + bool allow_uncharge, int nr_acct, struct pglist_data *pgdat, + enum node_stat_item idx) { - struct memcg_stock_pcp *stock; - struct obj_cgroup *old = NULL; - unsigned long flags; + struct obj_stock_pcp *stock; unsigned int nr_pages = 0; - local_lock_irqsave(&memcg_stock.stock_lock, flags); + if (!local_trylock(&obj_stock.lock)) { + if (pgdat) + mod_objcg_mlstate(objcg, pgdat, idx, nr_bytes); + nr_pages = nr_bytes >> PAGE_SHIFT; + nr_bytes = nr_bytes & (PAGE_SIZE - 1); + atomic_add(nr_bytes, &objcg->nr_charged_bytes); + goto out; + } - stock = this_cpu_ptr(&memcg_stock); + stock = this_cpu_ptr(&obj_stock); if (READ_ONCE(stock->cached_objcg) != objcg) { /* reset if necessary */ - old = drain_obj_stock(stock); + drain_obj_stock(stock); obj_cgroup_get(objcg); - WRITE_ONCE(stock->cached_objcg, objcg); stock->nr_bytes = atomic_read(&objcg->nr_charged_bytes) ? atomic_xchg(&objcg->nr_charged_bytes, 0) : 0; + WRITE_ONCE(stock->cached_objcg, objcg); + allow_uncharge = true; /* Allow uncharge when objcg changes */ } stock->nr_bytes += nr_bytes; + if (pgdat) + __account_obj_stock(objcg, stock, nr_acct, pgdat, idx); + if (allow_uncharge && (stock->nr_bytes > PAGE_SIZE)) { nr_pages = stock->nr_bytes >> PAGE_SHIFT; stock->nr_bytes &= (PAGE_SIZE - 1); } - local_unlock_irqrestore(&memcg_stock.stock_lock, flags); - obj_cgroup_put(old); - + local_unlock(&obj_stock.lock); +out: if (nr_pages) obj_cgroup_uncharge_pages(objcg, nr_pages); } -int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size) +static int obj_cgroup_charge_account(struct obj_cgroup *objcg, gfp_t gfp, size_t size, + struct pglist_data *pgdat, enum node_stat_item idx) { unsigned int nr_pages, nr_bytes; int ret; - if (consume_obj_stock(objcg, size)) + if (likely(consume_obj_stock(objcg, size, pgdat, idx))) return 0; /* @@ -2935,15 +3124,21 @@ int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size) nr_pages += 1; ret = obj_cgroup_charge_pages(objcg, gfp, nr_pages); - if (!ret && nr_bytes) - refill_obj_stock(objcg, PAGE_SIZE - nr_bytes, false); + if (!ret && (nr_bytes || pgdat)) + refill_obj_stock(objcg, nr_bytes ? PAGE_SIZE - nr_bytes : 0, + false, size, pgdat, idx); return ret; } +int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size) +{ + return obj_cgroup_charge_account(objcg, gfp, size, NULL, 0); +} + void obj_cgroup_uncharge(struct obj_cgroup *objcg, size_t size) { - refill_obj_stock(objcg, size, true); + refill_obj_stock(objcg, size, true, 0, NULL, 0); } static inline size_t obj_full_size(struct kmem_cache *s) @@ -2995,23 +3190,32 @@ bool __memcg_slab_post_alloc_hook(struct kmem_cache *s, struct list_lru *lru, return false; } - if (obj_cgroup_charge(objcg, flags, size * obj_full_size(s))) - return false; - for (i = 0; i < size; i++) { slab = virt_to_slab(p[i]); if (!slab_obj_exts(slab) && alloc_slab_obj_exts(slab, s, flags, false)) { - obj_cgroup_uncharge(objcg, obj_full_size(s)); continue; } + /* + * if we fail and size is 1, memcg_alloc_abort_single() will + * just free the object, which is ok as we have not assigned + * objcg to its obj_ext yet + * + * for larger sizes, kmem_cache_free_bulk() will uncharge + * any objects that were already charged and obj_ext assigned + * + * TODO: we could batch this until slab_pgdat(slab) changes + * between iterations, with a more complicated undo + */ + if (obj_cgroup_charge_account(objcg, flags, obj_full_size(s), + slab_pgdat(slab), cache_vmstat_idx(s))) + return false; + off = obj_to_index(s, slab, p[i]); obj_cgroup_get(objcg); slab_obj_exts(slab)[off].objcg = objcg; - mod_objcg_state(objcg, slab_pgdat(slab), - cache_vmstat_idx(s), obj_full_size(s)); } return true; @@ -3020,6 +3224,8 @@ bool __memcg_slab_post_alloc_hook(struct kmem_cache *s, struct list_lru *lru, void __memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, void **p, int objects, struct slabobj_ext *obj_exts) { + size_t obj_size = obj_full_size(s); + for (int i = 0; i < objects; i++) { struct obj_cgroup *objcg; unsigned int off; @@ -3030,33 +3236,40 @@ void __memcg_slab_free_hook(struct kmem_cache *s, struct slab *slab, continue; obj_exts[off].objcg = NULL; - obj_cgroup_uncharge(objcg, obj_full_size(s)); - mod_objcg_state(objcg, slab_pgdat(slab), cache_vmstat_idx(s), - -obj_full_size(s)); + refill_obj_stock(objcg, obj_size, true, -obj_size, + slab_pgdat(slab), cache_vmstat_idx(s)); obj_cgroup_put(objcg); } } /* - * Because folio_memcg(head) is not set on tails, set it now. + * The objcg is only set on the first page, so transfer it to all the + * other pages. */ -void split_page_memcg(struct page *head, int old_order, int new_order) +void split_page_memcg(struct page *page, unsigned order) { - struct folio *folio = page_folio(head); - int i; - unsigned int old_nr = 1 << old_order; - unsigned int new_nr = 1 << new_order; + struct obj_cgroup *objcg = page_objcg(page); + unsigned int i, nr = 1 << order; - if (mem_cgroup_disabled() || !folio_memcg_charged(folio)) + if (!objcg) return; - for (i = new_nr; i < old_nr; i += new_nr) - folio_page(folio, i)->memcg_data = folio->memcg_data; + for (i = 1; i < nr; i++) + page_set_objcg(&page[i], objcg); - if (folio_memcg_kmem(folio)) - obj_cgroup_get_many(__folio_objcg(folio), old_nr / new_nr - 1); - else - css_get_many(&folio_memcg(folio)->css, old_nr / new_nr - 1); + obj_cgroup_get_many(objcg, nr - 1); +} + +void folio_split_memcg_refs(struct folio *folio, unsigned old_order, + unsigned new_order) +{ + unsigned new_refs; + + if (mem_cgroup_disabled() || !folio_memcg_charged(folio)) + return; + + new_refs = (1 << (old_order - new_order)) - 1; + css_get_many(&__folio_memcg(folio)->css, new_refs); } unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap) @@ -3384,7 +3597,7 @@ void __maybe_unused mem_cgroup_id_get_many(struct mem_cgroup *memcg, refcount_add(n, &memcg->id.ref); } -void mem_cgroup_id_put_many(struct mem_cgroup *memcg, unsigned int n) +static void mem_cgroup_id_put_many(struct mem_cgroup *memcg, unsigned int n) { if (refcount_sub_and_test(n, &memcg->id.ref)) { mem_cgroup_id_remove(memcg); @@ -3399,6 +3612,24 @@ static inline void mem_cgroup_id_put(struct mem_cgroup *memcg) mem_cgroup_id_put_many(memcg, 1); } +struct mem_cgroup *mem_cgroup_id_get_online(struct mem_cgroup *memcg) +{ + while (!refcount_inc_not_zero(&memcg->id.ref)) { + /* + * The root cgroup cannot be destroyed, so it's refcount must + * always be >= 1. + */ + if (WARN_ON_ONCE(mem_cgroup_is_root(memcg))) { + VM_BUG_ON(1); + break; + } + memcg = parent_mem_cgroup(memcg); + if (!memcg) + memcg = root_mem_cgroup; + } + return memcg; +} + /** * mem_cgroup_from_id - look up a memcg from a memcg id * @id: the memcg id to look up @@ -3434,11 +3665,22 @@ struct mem_cgroup *mem_cgroup_get_from_ino(unsigned long ino) } #endif +static void free_mem_cgroup_per_node_info(struct mem_cgroup_per_node *pn) +{ + if (!pn) + return; + + free_percpu(pn->lruvec_stats_percpu); + kfree(pn->lruvec_stats); + kfree(pn); +} + static bool alloc_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node) { struct mem_cgroup_per_node *pn; - pn = kzalloc_node(sizeof(*pn), GFP_KERNEL, node); + pn = kmem_cache_alloc_node(memcg_pn_cachep, GFP_KERNEL | __GFP_ZERO, + node); if (!pn) return false; @@ -3458,23 +3700,10 @@ static bool alloc_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node) memcg->nodeinfo[node] = pn; return true; fail: - kfree(pn->lruvec_stats); - kfree(pn); + free_mem_cgroup_per_node_info(pn); return false; } -static void free_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node) -{ - struct mem_cgroup_per_node *pn = memcg->nodeinfo[node]; - - if (!pn) - return; - - free_percpu(pn->lruvec_stats_percpu); - kfree(pn->lruvec_stats); - kfree(pn); -} - static void __mem_cgroup_free(struct mem_cgroup *memcg) { int node; @@ -3482,7 +3711,7 @@ static void __mem_cgroup_free(struct mem_cgroup *memcg) obj_cgroup_put(memcg->orig_objcg); for_each_node(node) - free_mem_cgroup_per_node_info(memcg, node); + free_mem_cgroup_per_node_info(memcg->nodeinfo[node]); memcg1_free_events(memcg); kfree(memcg->vmstats); free_percpu(memcg->vmstats_percpu); @@ -3498,13 +3727,14 @@ static void mem_cgroup_free(struct mem_cgroup *memcg) static struct mem_cgroup *mem_cgroup_alloc(struct mem_cgroup *parent) { - struct memcg_vmstats_percpu *statc, *pstatc; + struct memcg_vmstats_percpu *statc; + struct memcg_vmstats_percpu __percpu *pstatc_pcpu; struct mem_cgroup *memcg; int node, cpu; int __maybe_unused i; long error; - memcg = kzalloc(struct_size(memcg, nodeinfo, nr_node_ids), GFP_KERNEL); + memcg = kmem_cache_zalloc(memcg_cachep, GFP_KERNEL); if (!memcg) return ERR_PTR(-ENOMEM); @@ -3529,9 +3759,9 @@ static struct mem_cgroup *mem_cgroup_alloc(struct mem_cgroup *parent) for_each_possible_cpu(cpu) { if (parent) - pstatc = per_cpu_ptr(parent->vmstats_percpu, cpu); + pstatc_pcpu = parent->vmstats_percpu; statc = per_cpu_ptr(memcg->vmstats_percpu, cpu); - statc->parent = parent ? pstatc : NULL; + statc->parent_pcpu = parent ? pstatc_pcpu : NULL; statc->vmstats = memcg->vmstats; } @@ -3547,7 +3777,10 @@ static struct mem_cgroup *mem_cgroup_alloc(struct mem_cgroup *parent) INIT_LIST_HEAD(&memcg->memory_peaks); INIT_LIST_HEAD(&memcg->swap_peaks); spin_lock_init(&memcg->peaks_lock); - memcg->socket_pressure = jiffies; + memcg->socket_pressure = get_jiffies_64(); +#if BITS_PER_LONG < 64 + seqlock_init(&memcg->socket_pressure_seqlock); +#endif memcg1_memcg_init(memcg); memcg->kmemcg_id = -1; INIT_LIST_HEAD(&memcg->objcg_list); @@ -3575,6 +3808,7 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) { struct mem_cgroup *parent = mem_cgroup_from_css(parent_css); struct mem_cgroup *memcg, *old_memcg; + bool memcg_on_dfl = cgroup_subsys_on_dfl(memory_cgrp_subsys); old_memcg = set_active_memcg(parent); memcg = mem_cgroup_alloc(parent); @@ -3592,9 +3826,10 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) if (parent) { WRITE_ONCE(memcg->swappiness, mem_cgroup_swappiness(parent)); - page_counter_init(&memcg->memory, &parent->memory, true); + page_counter_init(&memcg->memory, &parent->memory, memcg_on_dfl); page_counter_init(&memcg->swap, &parent->swap, false); #ifdef CONFIG_MEMCG_V1 + memcg->memory.track_failcnt = !memcg_on_dfl; WRITE_ONCE(memcg->oom_kill_disable, READ_ONCE(parent->oom_kill_disable)); page_counter_init(&memcg->kmem, &parent->kmem, false); page_counter_init(&memcg->tcpmem, &parent->tcpmem, false); @@ -3612,7 +3847,7 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) return &memcg->css; } - if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket) + if (memcg_on_dfl && !cgroup_memory_nosocket) static_branch_inc(&memcg_sockets_enabled_key); if (!cgroup_memory_nobpf) @@ -3677,6 +3912,7 @@ static void mem_cgroup_css_offline(struct cgroup_subsys_state *css) zswap_memcg_offline_cleanup(memcg); memcg_offline_kmem(memcg); + reparent_deferred_split_queue(memcg); reparent_shrinker_deferred(memcg); wb_memcg_offline(memcg); lru_gen_offline_memcg(memcg); @@ -3803,6 +4039,53 @@ static void mem_cgroup_stat_aggregate(struct aggregate_control *ac) } } +#ifdef CONFIG_MEMCG_NMI_SAFETY_REQUIRES_ATOMIC +static void flush_nmi_stats(struct mem_cgroup *memcg, struct mem_cgroup *parent, + int cpu) +{ + int nid; + + if (atomic_read(&memcg->kmem_stat)) { + int kmem = atomic_xchg(&memcg->kmem_stat, 0); + int index = memcg_stats_index(MEMCG_KMEM); + + memcg->vmstats->state[index] += kmem; + if (parent) + parent->vmstats->state_pending[index] += kmem; + } + + for_each_node_state(nid, N_MEMORY) { + struct mem_cgroup_per_node *pn = memcg->nodeinfo[nid]; + struct lruvec_stats *lstats = pn->lruvec_stats; + struct lruvec_stats *plstats = NULL; + + if (parent) + plstats = parent->nodeinfo[nid]->lruvec_stats; + + if (atomic_read(&pn->slab_reclaimable)) { + int slab = atomic_xchg(&pn->slab_reclaimable, 0); + int index = memcg_stats_index(NR_SLAB_RECLAIMABLE_B); + + lstats->state[index] += slab; + if (plstats) + plstats->state_pending[index] += slab; + } + if (atomic_read(&pn->slab_unreclaimable)) { + int slab = atomic_xchg(&pn->slab_unreclaimable, 0); + int index = memcg_stats_index(NR_SLAB_UNRECLAIMABLE_B); + + lstats->state[index] += slab; + if (plstats) + plstats->state_pending[index] += slab; + } + } +} +#else +static void flush_nmi_stats(struct mem_cgroup *memcg, struct mem_cgroup *parent, + int cpu) +{} +#endif + static void mem_cgroup_css_rstat_flush(struct cgroup_subsys_state *css, int cpu) { struct mem_cgroup *memcg = mem_cgroup_from_css(css); @@ -3811,6 +4094,8 @@ static void mem_cgroup_css_rstat_flush(struct cgroup_subsys_state *css, int cpu) struct aggregate_control ac; int nid; + flush_nmi_stats(memcg, parent, cpu); + statc = per_cpu_ptr(memcg->vmstats_percpu, cpu); ac = (struct aggregate_control) { @@ -3860,8 +4145,8 @@ static void mem_cgroup_css_rstat_flush(struct cgroup_subsys_state *css, int cpu) } WRITE_ONCE(statc->stats_updates, 0); /* We are in a per-cpu loop here, only do the atomic write once */ - if (atomic64_read(&memcg->vmstats->stats_updates)) - atomic64_set(&memcg->vmstats->stats_updates, 0); + if (atomic_read(&memcg->vmstats->stats_updates)) + atomic_set(&memcg->vmstats->stats_updates, 0); } static void mem_cgroup_fork(struct task_struct *task) @@ -4014,7 +4299,7 @@ static ssize_t peak_write(struct kernfs_open_file *of, char *buf, size_t nbytes, WRITE_ONCE(peer_ctx->value, usage); /* initial write, register watcher */ - if (ofp->value == -1) + if (ofp->value == OFP_PEAK_UNSET) list_add(&ofp->list, watchers); WRITE_ONCE(ofp->value, usage); @@ -4102,6 +4387,9 @@ static ssize_t memory_high_write(struct kernfs_open_file *of, page_counter_set_high(&memcg->memory, high); + if (of->file->f_flags & O_NONBLOCK) + goto out; + for (;;) { unsigned long nr_pages = page_counter_read(&memcg->memory); unsigned long reclaimed; @@ -4124,7 +4412,7 @@ static ssize_t memory_high_write(struct kernfs_open_file *of, if (!reclaimed && !nr_retries--) break; } - +out: memcg_wb_domain_size_changed(memcg); return nbytes; } @@ -4151,6 +4439,9 @@ static ssize_t memory_max_write(struct kernfs_open_file *of, xchg(&memcg->memory.max, max); + if (of->file->f_flags & O_NONBLOCK) + goto out; + for (;;) { unsigned long nr_pages = page_counter_read(&memcg->memory); @@ -4176,8 +4467,9 @@ static ssize_t memory_max_write(struct kernfs_open_file *of, memcg_memory_event(memcg, MEMCG_OOM); if (!mem_cgroup_out_of_memory(memcg, GFP_KERNEL, 0)) break; + cond_resched(); } - +out: memcg_wb_domain_size_changed(memcg); return nbytes; } @@ -4196,6 +4488,8 @@ static void __memory_events_show(struct seq_file *m, atomic_long_t *events) atomic_long_read(&events[MEMCG_OOM_KILL])); seq_printf(m, "oom_group_kill %lu\n", atomic_long_read(&events[MEMCG_OOM_GROUP_KILL])); + seq_printf(m, "sock_throttled %lu\n", + atomic_long_read(&events[MEMCG_SOCK_THROTTLED])); } static int memory_events_show(struct seq_file *m, void *v) @@ -4298,78 +4592,15 @@ static ssize_t memory_oom_group_write(struct kernfs_open_file *of, return nbytes; } -enum { - MEMORY_RECLAIM_SWAPPINESS = 0, - MEMORY_RECLAIM_NULL, -}; - -static const match_table_t tokens = { - { MEMORY_RECLAIM_SWAPPINESS, "swappiness=%d"}, - { MEMORY_RECLAIM_NULL, NULL }, -}; - static ssize_t memory_reclaim(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) { struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); - unsigned int nr_retries = MAX_RECLAIM_RETRIES; - unsigned long nr_to_reclaim, nr_reclaimed = 0; - int swappiness = -1; - unsigned int reclaim_options; - char *old_buf, *start; - substring_t args[MAX_OPT_ARGS]; - - buf = strstrip(buf); - - old_buf = buf; - nr_to_reclaim = memparse(buf, &buf) / PAGE_SIZE; - if (buf == old_buf) - return -EINVAL; - - buf = strstrip(buf); - - while ((start = strsep(&buf, " ")) != NULL) { - if (!strlen(start)) - continue; - switch (match_token(start, tokens, args)) { - case MEMORY_RECLAIM_SWAPPINESS: - if (match_int(&args[0], &swappiness)) - return -EINVAL; - if (swappiness < MIN_SWAPPINESS || swappiness > MAX_SWAPPINESS) - return -EINVAL; - break; - default: - return -EINVAL; - } - } - - reclaim_options = MEMCG_RECLAIM_MAY_SWAP | MEMCG_RECLAIM_PROACTIVE; - while (nr_reclaimed < nr_to_reclaim) { - /* Will converge on zero, but reclaim enforces a minimum */ - unsigned long batch_size = (nr_to_reclaim - nr_reclaimed) / 4; - unsigned long reclaimed; - - if (signal_pending(current)) - return -EINTR; - - /* - * This is the final attempt, drain percpu lru caches in the - * hope of introducing more evictable pages for - * try_to_free_mem_cgroup_pages(). - */ - if (!nr_retries) - lru_add_drain_all(); - - reclaimed = try_to_free_mem_cgroup_pages(memcg, - batch_size, GFP_KERNEL, - reclaim_options, - swappiness == -1 ? NULL : &swappiness); - - if (!reclaimed && !nr_retries--) - return -EAGAIN; + int ret; - nr_reclaimed += reclaimed; - } + ret = user_proactive_reclaim(buf, memcg, NULL); + if (ret) + return ret; return nbytes; } @@ -4498,7 +4729,9 @@ static int charge_memcg(struct folio *folio, struct mem_cgroup *memcg, if (ret) goto out; - mem_cgroup_commit_charge(folio, memcg); + css_get(&memcg->css); + commit_charge(folio, memcg); + memcg1_commit_charge(folio, memcg); out: return ret; } @@ -4516,38 +4749,37 @@ int __mem_cgroup_charge(struct folio *folio, struct mm_struct *mm, gfp_t gfp) } /** - * mem_cgroup_hugetlb_try_charge - try to charge the memcg for a hugetlb folio - * @memcg: memcg to charge. - * @gfp: reclaim mode. - * @nr_pages: number of pages to charge. - * - * This function is called when allocating a huge page folio to determine if - * the memcg has the capacity for it. It does not commit the charge yet, - * as the hugetlb folio itself has not been obtained from the hugetlb pool. + * mem_cgroup_charge_hugetlb - charge the memcg for a hugetlb folio + * @folio: folio being charged + * @gfp: reclaim mode * - * Once we have obtained the hugetlb folio, we can call - * mem_cgroup_commit_charge() to commit the charge. If we fail to obtain the - * folio, we should instead call mem_cgroup_cancel_charge() to undo the effect - * of try_charge(). + * This function is called when allocating a huge page folio, after the page has + * already been obtained and charged to the appropriate hugetlb cgroup + * controller (if it is enabled). * - * Returns 0 on success. Otherwise, an error code is returned. + * Returns ENOMEM if the memcg is already full. + * Returns 0 if either the charge was successful, or if we skip the charging. */ -int mem_cgroup_hugetlb_try_charge(struct mem_cgroup *memcg, gfp_t gfp, - long nr_pages) +int mem_cgroup_charge_hugetlb(struct folio *folio, gfp_t gfp) { + struct mem_cgroup *memcg = get_mem_cgroup_from_current(); + int ret = 0; + /* - * If hugetlb memcg charging is not enabled, do not fail hugetlb allocation, - * but do not attempt to commit charge later (or cancel on error) either. + * Even memcg does not account for hugetlb, we still want to update + * system-level stats via lruvec_stat_mod_folio. Return 0, and skip + * charging the memcg. */ - if (mem_cgroup_disabled() || !memcg || - !cgroup_subsys_on_dfl(memory_cgrp_subsys) || - !(cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING)) - return -EOPNOTSUPP; + if (mem_cgroup_disabled() || !memcg_accounts_hugetlb() || + !memcg || !cgroup_subsys_on_dfl(memory_cgrp_subsys)) + goto out; - if (try_charge(memcg, gfp, nr_pages)) - return -ENOMEM; + if (charge_memcg(folio, memcg, gfp)) + ret = -ENOMEM; - return 0; +out: + mem_cgroup_put(memcg); + return ret; } /** @@ -4585,40 +4817,6 @@ int mem_cgroup_swapin_charge_folio(struct folio *folio, struct mm_struct *mm, return ret; } -/* - * mem_cgroup_swapin_uncharge_swap - uncharge swap slot - * @entry: the first swap entry for which the pages are charged - * @nr_pages: number of pages which will be uncharged - * - * Call this function after successfully adding the charged page to swapcache. - * - * Note: This function assumes the page for which swap slot is being uncharged - * is order 0 page. - */ -void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry, unsigned int nr_pages) -{ - /* - * Cgroup1's unified memory+swap counter has been charged with the - * new swapcache page, finish the transfer by uncharging the swap - * slot. The swap slot would also get uncharged when it dies, but - * it can stick around indefinitely and we'd count the page twice - * the entire time. - * - * Cgroup2 has separate resource counters for memory and swap, - * so this is a non-issue here. Memory and swap charge lifetimes - * correspond 1:1 to page and swap slot lifetimes: we charge the - * page to memory here, and uncharge swap when the slot is freed. - */ - if (!mem_cgroup_disabled() && do_memsw_account()) { - /* - * The swap entry might not get freed for a long time, - * let's not wait for it. The page already received a - * memory+swap charge, drop the swap entry duplicate. - */ - mem_cgroup_uncharge_swap(entry, nr_pages); - } -} - struct uncharge_gather { struct mem_cgroup *memcg; unsigned long nr_memory; @@ -4635,9 +4833,7 @@ static inline void uncharge_gather_clear(struct uncharge_gather *ug) static void uncharge_batch(const struct uncharge_gather *ug) { if (ug->nr_memory) { - page_counter_uncharge(&ug->memcg->memory, ug->nr_memory); - if (do_memsw_account()) - page_counter_uncharge(&ug->memcg->memsw, ug->nr_memory); + memcg_uncharge(ug->memcg, ug->nr_memory); if (ug->nr_kmem) { mod_memcg_state(ug->memcg, MEMCG_KMEM, -ug->nr_kmem); memcg1_account_kmem(ug->memcg, -ug->nr_kmem); @@ -4850,26 +5046,46 @@ out: void mem_cgroup_sk_free(struct sock *sk) { - if (sk->sk_memcg) - css_put(&sk->sk_memcg->css); + struct mem_cgroup *memcg = mem_cgroup_from_sk(sk); + + if (memcg) + css_put(&memcg->css); +} + +void mem_cgroup_sk_inherit(const struct sock *sk, struct sock *newsk) +{ + struct mem_cgroup *memcg; + + if (sk->sk_memcg == newsk->sk_memcg) + return; + + mem_cgroup_sk_free(newsk); + + memcg = mem_cgroup_from_sk(sk); + if (memcg) + css_get(&memcg->css); + + newsk->sk_memcg = sk->sk_memcg; } /** - * mem_cgroup_charge_skmem - charge socket memory - * @memcg: memcg to charge + * mem_cgroup_sk_charge - charge socket memory + * @sk: socket in memcg to charge * @nr_pages: number of pages to charge * @gfp_mask: reclaim mode * * Charges @nr_pages to @memcg. Returns %true if the charge fit within * @memcg's configured limit, %false if it doesn't. */ -bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages, - gfp_t gfp_mask) +bool mem_cgroup_sk_charge(const struct sock *sk, unsigned int nr_pages, + gfp_t gfp_mask) { + struct mem_cgroup *memcg = mem_cgroup_from_sk(sk); + if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) return memcg1_charge_skmem(memcg, nr_pages, gfp_mask); - if (try_charge(memcg, gfp_mask, nr_pages) == 0) { + if (try_charge_memcg(memcg, gfp_mask, nr_pages) == 0) { mod_memcg_state(memcg, MEMCG_SOCK, nr_pages); return true; } @@ -4878,12 +5094,14 @@ bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages, } /** - * mem_cgroup_uncharge_skmem - uncharge socket memory - * @memcg: memcg to uncharge + * mem_cgroup_sk_uncharge - uncharge socket memory + * @sk: socket in memcg to uncharge * @nr_pages: number of pages to uncharge */ -void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages) +void mem_cgroup_sk_uncharge(const struct sock *sk, unsigned int nr_pages) { + struct mem_cgroup *memcg = mem_cgroup_from_sk(sk); + if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { memcg1_uncharge_skmem(memcg, nr_pages); return; @@ -4913,15 +5131,16 @@ static int __init cgroup_memory(char *s) __setup("cgroup.memory=", cgroup_memory); /* - * subsys_initcall() for memory controller. + * Memory controller init before cgroup_init() initialize root_mem_cgroup. * * Some parts like memcg_hotplug_cpu_dead() have to be initialized from this * context because of lock dependencies (cgroup_lock -> cpu hotplug) but * basically everything that doesn't depend on a specific mem_cgroup structure * should be initialized from here. */ -static int __init mem_cgroup_init(void) +int __init mem_cgroup_init(void) { + unsigned int memcg_size; int cpu; /* @@ -4935,92 +5154,24 @@ static int __init mem_cgroup_init(void) cpuhp_setup_state_nocalls(CPUHP_MM_MEMCQ_DEAD, "mm/memctrl:dead", NULL, memcg_hotplug_cpu_dead); - for_each_possible_cpu(cpu) + for_each_possible_cpu(cpu) { INIT_WORK(&per_cpu_ptr(&memcg_stock, cpu)->work, - drain_local_stock); - - return 0; -} -subsys_initcall(mem_cgroup_init); - -#ifdef CONFIG_SWAP -static struct mem_cgroup *mem_cgroup_id_get_online(struct mem_cgroup *memcg) -{ - while (!refcount_inc_not_zero(&memcg->id.ref)) { - /* - * The root cgroup cannot be destroyed, so it's refcount must - * always be >= 1. - */ - if (WARN_ON_ONCE(mem_cgroup_is_root(memcg))) { - VM_BUG_ON(1); - break; - } - memcg = parent_mem_cgroup(memcg); - if (!memcg) - memcg = root_mem_cgroup; + drain_local_memcg_stock); + INIT_WORK(&per_cpu_ptr(&obj_stock, cpu)->work, + drain_local_obj_stock); } - return memcg; -} - -/** - * mem_cgroup_swapout - transfer a memsw charge to swap - * @folio: folio whose memsw charge to transfer - * @entry: swap entry to move the charge to - * - * Transfer the memsw charge of @folio to @entry. - */ -void mem_cgroup_swapout(struct folio *folio, swp_entry_t entry) -{ - struct mem_cgroup *memcg, *swap_memcg; - unsigned int nr_entries; - unsigned short oldid; - - VM_BUG_ON_FOLIO(folio_test_lru(folio), folio); - VM_BUG_ON_FOLIO(folio_ref_count(folio), folio); - - if (mem_cgroup_disabled()) - return; - - if (!do_memsw_account()) - return; - - memcg = folio_memcg(folio); - - VM_WARN_ON_ONCE_FOLIO(!memcg, folio); - if (!memcg) - return; - - /* - * In case the memcg owning these pages has been offlined and doesn't - * have an ID allocated to it anymore, charge the closest online - * ancestor for the swap instead and transfer the memory+swap charge. - */ - swap_memcg = mem_cgroup_id_get_online(memcg); - nr_entries = folio_nr_pages(folio); - /* Get references for the tail pages, too */ - if (nr_entries > 1) - mem_cgroup_id_get_many(swap_memcg, nr_entries - 1); - oldid = swap_cgroup_record(entry, mem_cgroup_id(swap_memcg), - nr_entries); - VM_BUG_ON_FOLIO(oldid, folio); - mod_memcg_state(swap_memcg, MEMCG_SWAP, nr_entries); - - folio_unqueue_deferred_split(folio); - folio->memcg_data = 0; - if (!mem_cgroup_is_root(memcg)) - page_counter_uncharge(&memcg->memory, nr_entries); + memcg_size = struct_size_t(struct mem_cgroup, nodeinfo, nr_node_ids); + memcg_cachep = kmem_cache_create("mem_cgroup", memcg_size, 0, + SLAB_PANIC | SLAB_HWCACHE_ALIGN, NULL); - if (memcg != swap_memcg) { - if (!mem_cgroup_is_root(swap_memcg)) - page_counter_charge(&swap_memcg->memsw, nr_entries); - page_counter_uncharge(&memcg->memsw, nr_entries); - } + memcg_pn_cachep = KMEM_CACHE(mem_cgroup_per_node, + SLAB_PANIC | SLAB_HWCACHE_ALIGN); - memcg1_swapout(folio, memcg); - css_put(&memcg->css); + return 0; } +#ifdef CONFIG_SWAP /** * __mem_cgroup_try_charge_swap - try charging swap space for a folio * @folio: folio being added to swap @@ -5035,7 +5186,6 @@ int __mem_cgroup_try_charge_swap(struct folio *folio, swp_entry_t entry) unsigned int nr_pages = folio_nr_pages(folio); struct page_counter *counter; struct mem_cgroup *memcg; - unsigned short oldid; if (do_memsw_account()) return 0; @@ -5064,10 +5214,10 @@ int __mem_cgroup_try_charge_swap(struct folio *folio, swp_entry_t entry) /* Get references for the tail pages, too */ if (nr_pages > 1) mem_cgroup_id_get_many(memcg, nr_pages - 1); - oldid = swap_cgroup_record(entry, mem_cgroup_id(memcg), nr_pages); - VM_BUG_ON_FOLIO(oldid, folio); mod_memcg_state(memcg, MEMCG_SWAP, nr_pages); + swap_cgroup_record(folio, mem_cgroup_id(memcg), entry); + return 0; } @@ -5081,7 +5231,7 @@ void __mem_cgroup_uncharge_swap(swp_entry_t entry, unsigned int nr_pages) struct mem_cgroup *memcg; unsigned short id; - id = swap_cgroup_record(entry, 0, nr_pages); + id = swap_cgroup_clear(entry, nr_pages); rcu_read_lock(); memcg = mem_cgroup_from_id(id); if (memcg) { @@ -5320,7 +5470,7 @@ bool obj_cgroup_may_zswap(struct obj_cgroup *objcg) * @size: size of compressed object * * This forces the charge after obj_cgroup_may_zswap() allowed - * compression and storage in zwap for this cgroup to go ahead. + * compression and storage in zswap for this cgroup to go ahead. */ void obj_cgroup_charge_zswap(struct obj_cgroup *objcg, size_t size) { @@ -5473,3 +5623,21 @@ static int __init mem_cgroup_swap_init(void) subsys_initcall(mem_cgroup_swap_init); #endif /* CONFIG_SWAP */ + +bool mem_cgroup_node_allowed(struct mem_cgroup *memcg, int nid) +{ + return memcg ? cpuset_node_allowed(memcg->css.cgroup, nid) : true; +} + +void mem_cgroup_show_protected_memory(struct mem_cgroup *memcg) +{ + if (mem_cgroup_disabled() || !cgroup_subsys_on_dfl(memory_cgrp_subsys)) + return; + + if (!memcg) + memcg = root_mem_cgroup; + + pr_warn("Memory cgroup min protection %lukB -- low protection %lukB", + K(atomic_long_read(&memcg->memory.children_min_usage)*PAGE_SIZE), + K(atomic_long_read(&memcg->memory.children_low_usage)*PAGE_SIZE)); +} |