[patch 081/163] mm: memcontrol: account kernel stack per node

Andrew Morton
2020-08-07T06:21:41Z

From: Shakeel Butt <shakeelb@google.com>
Subject: mm: memcontrol: account kernel stack per node

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().

Link: http://lkml.kernel.org/r/20200630161539.1759185-1-shakeelb@google.com
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

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(-)

--- a/drivers/base/node.c~mm-memcontrol-account-kernel-stack-per-node
+++ a/drivers/base/node.c
@@ -440,9 +440,9 @@ static ssize_t node_read_meminfo(struct
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,
--- a/fs/proc/meminfo.c~mm-memcontrol-account-kernel-stack-per-node
+++ a/fs/proc/meminfo.c
@@ -101,10 +101,10 @@ static int meminfo_proc_show(struct seq_
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));
--- a/include/linux/memcontrol.h~mm-memcontrol-account-kernel-stack-per-node
+++ a/include/linux/memcontrol.h
@@ -32,8 +32,6 @@ struct kmem_cache;
enum memcg_stat_item {
MEMCG_SWAP = NR_VM_NODE_STAT_ITEMS,
MEMCG_SOCK,
- /* XXX: why are these zone and not node counters? */
- MEMCG_KERNEL_STACK_KB,
MEMCG_NR_STAT,
};

@@ -729,8 +727,19 @@ void __mod_memcg_lruvec_state(struct lru
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)
{
@@ -1151,6 +1160,14 @@ static inline void __mod_lruvec_slab_sta
__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)
{
}
--- a/include/linux/mmzone.h~mm-memcontrol-account-kernel-stack-per-node
+++ a/include/linux/mmzone.h
@@ -155,10 +155,6 @@ 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)
@@ -203,6 +199,10 @@ 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
};

--- a/kernel/fork.c~mm-memcontrol-account-kernel-stack-per-node
+++ a/kernel/fork.c
@@ -276,13 +276,8 @@ static inline void free_thread_stack(str
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
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(str
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
--- a/kernel/scs.c~mm-memcontrol-account-kernel-stack-per-node
+++ a/kernel/scs.c
@@ -17,7 +17,7 @@ static void __scs_account(void *s, int a
{
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));
}

--- a/mm/memcontrol.c~mm-memcontrol-account-kernel-stack-per-node
+++ a/mm/memcontrol.c
@@ -1485,7 +1485,7 @@ static char *memory_stat_format(struct m
(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) +
--- a/mm/page_alloc.c~mm-memcontrol-account-kernel-stack-per-node
+++ a/mm/page_alloc.c
@@ -5396,6 +5396,10 @@ void show_free_areas(unsigned int filter
" 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,
@@ -5417,6 +5421,10 @@ void show_free_areas(unsigned int filter
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");
}
@@ -5448,10 +5456,6 @@ void show_free_areas(unsigned int filter
" 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"
@@ -5473,10 +5477,6 @@ void show_free_areas(unsigned int filter
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),
--- a/mm/vmstat.c~mm-memcontrol-account-kernel-stack-per-node
+++ a/mm/vmstat.c
@@ -1140,10 +1140,6 @@ 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",
@@ -1194,6 +1190,10 @@ 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",
_