On Tue, Jun 30, 2020 at 09:15:39AM -0700, Shakeel Butt wrote: > Currently the kernel stack is being accounted per-zone. There is no need > to do that. In addition due to being per-zone, memcg has to keep a > separate MEMCG_KERNEL_STACK_KB. Make the stat per-node and deprecate > MEMCG_KERNEL_STACK_KB as memcg_stat_item is an extension of > node_stat_item. In addition localize the kernel stack stats updates to > account_kernel_stack(). > > Signed-off-by: Shakeel Butt <shakeelb@xxxxxxxxxx> > --- > Changes since v1: > - Use lruvec based stat update functions based on Roman's suggestion. Reviewed-by: Roman Gushchin <guro@xxxxxx> I really like it, it makes this complicated code way simpler. Thanks, Shakeel! > > drivers/base/node.c | 4 +-- > fs/proc/meminfo.c | 4 +-- > include/linux/memcontrol.h | 21 ++++++++++++++-- > include/linux/mmzone.h | 8 +++--- > kernel/fork.c | 51 +++++++++++--------------------------- > kernel/scs.c | 2 +- > mm/memcontrol.c | 2 +- > mm/page_alloc.c | 16 ++++++------ > mm/vmstat.c | 8 +++--- > 9 files changed, 55 insertions(+), 61 deletions(-) > > diff --git a/drivers/base/node.c b/drivers/base/node.c > index 0cf13e31603c..508b80f6329b 100644 > --- a/drivers/base/node.c > +++ b/drivers/base/node.c > @@ -440,9 +440,9 @@ static ssize_t node_read_meminfo(struct device *dev, > nid, K(node_page_state(pgdat, NR_FILE_MAPPED)), > nid, K(node_page_state(pgdat, NR_ANON_MAPPED)), > nid, K(i.sharedram), > - nid, sum_zone_node_page_state(nid, NR_KERNEL_STACK_KB), > + nid, node_page_state(pgdat, NR_KERNEL_STACK_KB), > #ifdef CONFIG_SHADOW_CALL_STACK > - nid, sum_zone_node_page_state(nid, NR_KERNEL_SCS_KB), > + nid, node_page_state(pgdat, NR_KERNEL_SCS_KB), > #endif > nid, K(sum_zone_node_page_state(nid, NR_PAGETABLE)), > nid, 0UL, > diff --git a/fs/proc/meminfo.c b/fs/proc/meminfo.c > index f262bff3ca31..887a5532e449 100644 > --- a/fs/proc/meminfo.c > +++ b/fs/proc/meminfo.c > @@ -101,10 +101,10 @@ static int meminfo_proc_show(struct seq_file *m, void *v) > show_val_kb(m, "SReclaimable: ", sreclaimable); > show_val_kb(m, "SUnreclaim: ", sunreclaim); > seq_printf(m, "KernelStack: %8lu kB\n", > - global_zone_page_state(NR_KERNEL_STACK_KB)); > + global_node_page_state(NR_KERNEL_STACK_KB)); > #ifdef CONFIG_SHADOW_CALL_STACK > seq_printf(m, "ShadowCallStack:%8lu kB\n", > - global_zone_page_state(NR_KERNEL_SCS_KB)); > + global_node_page_state(NR_KERNEL_SCS_KB)); > #endif > show_val_kb(m, "PageTables: ", > global_zone_page_state(NR_PAGETABLE)); > diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h > index ba1e42715ecf..b8f52a3fed90 100644 > --- a/include/linux/memcontrol.h > +++ b/include/linux/memcontrol.h > @@ -33,8 +33,6 @@ enum memcg_stat_item { > MEMCG_SWAP = NR_VM_NODE_STAT_ITEMS, > MEMCG_SOCK, > MEMCG_PERCPU_B, > - /* XXX: why are these zone and not node counters? */ > - MEMCG_KERNEL_STACK_KB, > MEMCG_NR_STAT, > }; > > @@ -737,8 +735,19 @@ void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, > void __mod_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx, > int val); > void __mod_lruvec_slab_state(void *p, enum node_stat_item idx, int val); > + > void mod_memcg_obj_state(void *p, int idx, int val); > > +static inline void mod_lruvec_slab_state(void *p, enum node_stat_item idx, > + int val) > +{ > + unsigned long flags; > + > + local_irq_save(flags); > + __mod_lruvec_slab_state(p, idx, val); > + local_irq_restore(flags); > +} > + > static inline void mod_memcg_lruvec_state(struct lruvec *lruvec, > enum node_stat_item idx, int val) > { > @@ -1159,6 +1168,14 @@ static inline void __mod_lruvec_slab_state(void *p, enum node_stat_item idx, > __mod_node_page_state(page_pgdat(page), idx, val); > } > > +static inline void mod_lruvec_slab_state(void *p, enum node_stat_item idx, > + int val) > +{ > + struct page *page = virt_to_head_page(p); > + > + mod_node_page_state(page_pgdat(page), idx, val); > +} > + > static inline void mod_memcg_obj_state(void *p, int idx, int val) > { > } > diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h > index 8e859444927a..b79f73ce8b57 100644 > --- a/include/linux/mmzone.h > +++ b/include/linux/mmzone.h > @@ -153,10 +153,6 @@ enum zone_stat_item { > NR_ZONE_WRITE_PENDING, /* Count of dirty, writeback and unstable pages */ > NR_MLOCK, /* mlock()ed pages found and moved off LRU */ > NR_PAGETABLE, /* used for pagetables */ > - NR_KERNEL_STACK_KB, /* measured in KiB */ > -#if IS_ENABLED(CONFIG_SHADOW_CALL_STACK) > - NR_KERNEL_SCS_KB, /* measured in KiB */ > -#endif > /* Second 128 byte cacheline */ > NR_BOUNCE, > #if IS_ENABLED(CONFIG_ZSMALLOC) > @@ -201,6 +197,10 @@ enum node_stat_item { > NR_KERNEL_MISC_RECLAIMABLE, /* reclaimable non-slab kernel pages */ > NR_FOLL_PIN_ACQUIRED, /* via: pin_user_page(), gup flag: FOLL_PIN */ > NR_FOLL_PIN_RELEASED, /* pages returned via unpin_user_page() */ > + NR_KERNEL_STACK_KB, /* measured in KiB */ > +#if IS_ENABLED(CONFIG_SHADOW_CALL_STACK) > + NR_KERNEL_SCS_KB, /* measured in KiB */ > +#endif > NR_VM_NODE_STAT_ITEMS > }; > > diff --git a/kernel/fork.c b/kernel/fork.c > index 73fdfa9674b5..f00c7a4913e1 100644 > --- a/kernel/fork.c > +++ b/kernel/fork.c > @@ -276,13 +276,8 @@ static inline void free_thread_stack(struct task_struct *tsk) > if (vm) { > int i; > > - for (i = 0; i < THREAD_SIZE / PAGE_SIZE; i++) { > - mod_memcg_page_state(vm->pages[i], > - MEMCG_KERNEL_STACK_KB, > - -(int)(PAGE_SIZE / 1024)); > - > + for (i = 0; i < THREAD_SIZE / PAGE_SIZE; i++) > memcg_kmem_uncharge_page(vm->pages[i], 0); > - } > > for (i = 0; i < NR_CACHED_STACKS; i++) { > if (this_cpu_cmpxchg(cached_stacks[i], > @@ -382,31 +377,14 @@ static void account_kernel_stack(struct task_struct *tsk, int account) > void *stack = task_stack_page(tsk); > struct vm_struct *vm = task_stack_vm_area(tsk); > > - BUILD_BUG_ON(IS_ENABLED(CONFIG_VMAP_STACK) && PAGE_SIZE % 1024 != 0); > - > - if (vm) { > - int i; > - > - BUG_ON(vm->nr_pages != THREAD_SIZE / PAGE_SIZE); > > - for (i = 0; i < THREAD_SIZE / PAGE_SIZE; i++) { > - mod_zone_page_state(page_zone(vm->pages[i]), > - NR_KERNEL_STACK_KB, > - PAGE_SIZE / 1024 * account); > - } > - } else { > - /* > - * All stack pages are in the same zone and belong to the > - * same memcg. > - */ > - struct page *first_page = virt_to_page(stack); > - > - mod_zone_page_state(page_zone(first_page), NR_KERNEL_STACK_KB, > - THREAD_SIZE / 1024 * account); > - > - mod_memcg_obj_state(stack, MEMCG_KERNEL_STACK_KB, > - account * (THREAD_SIZE / 1024)); > - } > + /* All stack pages are in the same node. */ > + if (vm) > + mod_lruvec_page_state(vm->pages[0], NR_KERNEL_STACK_KB, > + account * (THREAD_SIZE / 1024)); > + else > + mod_lruvec_slab_state(stack, NR_KERNEL_STACK_KB, > + account * (THREAD_SIZE / 1024)); > } > > static int memcg_charge_kernel_stack(struct task_struct *tsk) > @@ -415,24 +393,23 @@ static int memcg_charge_kernel_stack(struct task_struct *tsk) > struct vm_struct *vm = task_stack_vm_area(tsk); > int ret; > > + BUILD_BUG_ON(IS_ENABLED(CONFIG_VMAP_STACK) && PAGE_SIZE % 1024 != 0); > + > if (vm) { > int i; > > + BUG_ON(vm->nr_pages != THREAD_SIZE / PAGE_SIZE); > + > for (i = 0; i < THREAD_SIZE / PAGE_SIZE; i++) { > /* > * If memcg_kmem_charge_page() fails, page->mem_cgroup > - * pointer is NULL, and both memcg_kmem_uncharge_page() > - * and mod_memcg_page_state() in free_thread_stack() > - * will ignore this page. So it's safe. > + * pointer is NULL, and memcg_kmem_uncharge_page() in > + * free_thread_stack() will ignore this page. > */ > ret = memcg_kmem_charge_page(vm->pages[i], GFP_KERNEL, > 0); > if (ret) > return ret; > - > - mod_memcg_page_state(vm->pages[i], > - MEMCG_KERNEL_STACK_KB, > - PAGE_SIZE / 1024); > } > } > #endif > diff --git a/kernel/scs.c b/kernel/scs.c > index 5d4d9bbdec36..4ff4a7ba0094 100644 > --- a/kernel/scs.c > +++ b/kernel/scs.c > @@ -17,7 +17,7 @@ static void __scs_account(void *s, int account) > { > struct page *scs_page = virt_to_page(s); > > - mod_zone_page_state(page_zone(scs_page), NR_KERNEL_SCS_KB, > + mod_node_page_state(page_pgdat(scs_page), NR_KERNEL_SCS_KB, > account * (SCS_SIZE / SZ_1K)); > } > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index b1a644224383..06de63901f81 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -1485,7 +1485,7 @@ static char *memory_stat_format(struct mem_cgroup *memcg) > (u64)memcg_page_state(memcg, NR_FILE_PAGES) * > PAGE_SIZE); > seq_buf_printf(&s, "kernel_stack %llu\n", > - (u64)memcg_page_state(memcg, MEMCG_KERNEL_STACK_KB) * > + (u64)memcg_page_state(memcg, NR_KERNEL_STACK_KB) * > 1024); > seq_buf_printf(&s, "slab %llu\n", > (u64)(memcg_page_state(memcg, NR_SLAB_RECLAIMABLE_B) + > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 174c849ba9f2..0568b126f719 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -5402,6 +5402,10 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask) > " anon_thp: %lukB" > #endif > " writeback_tmp:%lukB" > + " kernel_stack:%lukB" > +#ifdef CONFIG_SHADOW_CALL_STACK > + " shadow_call_stack:%lukB" > +#endif > " all_unreclaimable? %s" > "\n", > pgdat->node_id, > @@ -5423,6 +5427,10 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask) > K(node_page_state(pgdat, NR_ANON_THPS) * HPAGE_PMD_NR), > #endif > K(node_page_state(pgdat, NR_WRITEBACK_TEMP)), > + node_page_state(pgdat, NR_KERNEL_STACK_KB), > +#ifdef CONFIG_SHADOW_CALL_STACK > + node_page_state(pgdat, NR_KERNEL_SCS_KB), > +#endif > pgdat->kswapd_failures >= MAX_RECLAIM_RETRIES ? > "yes" : "no"); > } > @@ -5454,10 +5462,6 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask) > " present:%lukB" > " managed:%lukB" > " mlocked:%lukB" > - " kernel_stack:%lukB" > -#ifdef CONFIG_SHADOW_CALL_STACK > - " shadow_call_stack:%lukB" > -#endif > " pagetables:%lukB" > " bounce:%lukB" > " free_pcp:%lukB" > @@ -5479,10 +5483,6 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask) > K(zone->present_pages), > K(zone_managed_pages(zone)), > K(zone_page_state(zone, NR_MLOCK)), > - zone_page_state(zone, NR_KERNEL_STACK_KB), > -#ifdef CONFIG_SHADOW_CALL_STACK > - zone_page_state(zone, NR_KERNEL_SCS_KB), > -#endif > K(zone_page_state(zone, NR_PAGETABLE)), > K(zone_page_state(zone, NR_BOUNCE)), > K(free_pcp), > diff --git a/mm/vmstat.c b/mm/vmstat.c > index 2c5a96694490..96bf8bfffd1d 100644 > --- a/mm/vmstat.c > +++ b/mm/vmstat.c > @@ -1158,10 +1158,6 @@ const char * const vmstat_text[] = { > "nr_zone_write_pending", > "nr_mlock", > "nr_page_table_pages", > - "nr_kernel_stack", > -#if IS_ENABLED(CONFIG_SHADOW_CALL_STACK) > - "nr_shadow_call_stack", > -#endif > "nr_bounce", > #if IS_ENABLED(CONFIG_ZSMALLOC) > "nr_zspages", > @@ -1212,6 +1208,10 @@ const char * const vmstat_text[] = { > "nr_kernel_misc_reclaimable", > "nr_foll_pin_acquired", > "nr_foll_pin_released", > + "nr_kernel_stack", > +#if IS_ENABLED(CONFIG_SHADOW_CALL_STACK) > + "nr_shadow_call_stack", > +#endif > > /* enum writeback_stat_item counters */ > "nr_dirty_threshold", > -- > 2.27.0.212.ge8ba1cc988-goog >