2024-04-15 03:11:59

by xu.xin16

[permalink] [raw]
Subject: [PATCH] mm: thp: makes the memcg THP deferred split shrinker aware of node_id

From: Ran Xiaokai <[email protected]>

Since commit 87eaceb3faa5 ("mm: thp: make deferred split shrinker
memcg aware"), the THP deferred split queue is per memcg but not
per mem_cgroup_per_node. This has two aspects of impact:

Impact1: for kswapd reclaim
=====================
kswapd
balance_pgdat
kswapd_shrink_node
shrink_node(pgdat, sc);
shrink_node_memcgs(pgdat, sc);
shrink_slab(sc->gfp_mask, pgdat->node_id, memcg...);
the parameter "pgdat->node_id" does not take effectct for
THP deferred_split_shrinker, as the deferred_split_queue of
specified memcg is not for a certain numa node but for all the nodes.
We want to makes the memcg THP deferred split shrinker aware of
node_id.

Impact2: thp-deferred_split shrinker debugfs interface
=========================================
for the "count" file:
<cgroup inode id> <objects on node 0> <objects on node 1>
the output is acctually the sum of all numa nodes.
for the "scan" file:
<cgroup inode id> <numa id> <number of objects to scan>
Also the "numa id" input does not take effect here.

This patch makes memcg deferred_split_queue per mem_cgroup_per_node
so try to conform to semantic logic.

Reviewed-by: Lu Zhongjun <[email protected]>
Signed-off-by: Ran Xiaokai <[email protected]>
Cc: xu xin <[email protected]>
Cc: Yang Yang <[email protected]>
---
include/linux/memcontrol.h | 7 +++----
mm/huge_memory.c | 6 +++---
mm/memcontrol.c | 11 +++++------
3 files changed, 11 insertions(+), 13 deletions(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 394fd0a887ae..7282861d5a5d 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -130,6 +130,9 @@ struct mem_cgroup_per_node {
bool on_tree;
struct mem_cgroup *memcg; /* Back pointer, we cannot */
/* use container_of */
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+ struct deferred_split deferred_split_queue;
+#endif
};

struct mem_cgroup_threshold {
@@ -327,10 +330,6 @@ struct mem_cgroup {
struct list_head event_list;
spinlock_t event_list_lock;

-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
- struct deferred_split deferred_split_queue;
-#endif
-
#ifdef CONFIG_LRU_GEN_WALKS_MMU
/* per-memcg mm_struct list */
struct lru_gen_mm_list mm_list;
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 9859aa4f7553..338d071070a6 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -774,7 +774,7 @@ struct deferred_split *get_deferred_split_queue(struct folio *folio)
struct pglist_data *pgdat = NODE_DATA(folio_nid(folio));

if (memcg)
- return &memcg->deferred_split_queue;
+ return &memcg->nodeinfo[pgdat->node_id]->deferred_split_queue;
else
return &pgdat->deferred_split_queue;
}
@@ -3305,7 +3305,7 @@ static unsigned long deferred_split_count(struct shrinker *shrink,

#ifdef CONFIG_MEMCG
if (sc->memcg)
- ds_queue = &sc->memcg->deferred_split_queue;
+ ds_queue = &sc->memcg->nodeinfo[sc->nid]->deferred_split_queue;
#endif
return READ_ONCE(ds_queue->split_queue_len);
}
@@ -3322,7 +3322,7 @@ static unsigned long deferred_split_scan(struct shrinker *shrink,

#ifdef CONFIG_MEMCG
if (sc->memcg)
- ds_queue = &sc->memcg->deferred_split_queue;
+ ds_queue = &sc->memcg->nodeinfo[sc->nid]->deferred_split_queue;
#endif

spin_lock_irqsave(&ds_queue->split_queue_lock, flags);
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index fabce2b50c69..cdf9f5fa3b8e 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -5445,7 +5445,11 @@ static int alloc_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node)
kfree(pn);
return 1;
}
-
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+ spin_lock_init(&pn->deferred_split_queue.split_queue_lock);
+ INIT_LIST_HEAD(&pn->deferred_split_queue.split_queue);
+ pn->deferred_split_queue.split_queue_len = 0;
+#endif
lruvec_init(&pn->lruvec);
pn->memcg = memcg;

@@ -5545,11 +5549,6 @@ static struct mem_cgroup *mem_cgroup_alloc(struct mem_cgroup *parent)
for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++)
memcg->cgwb_frn[i].done =
__WB_COMPLETION_INIT(&memcg_cgwb_frn_waitq);
-#endif
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
- spin_lock_init(&memcg->deferred_split_queue.split_queue_lock);
- INIT_LIST_HEAD(&memcg->deferred_split_queue.split_queue);
- memcg->deferred_split_queue.split_queue_len = 0;
#endif
lru_gen_init_memcg(memcg);
return memcg;
--
2.15.2


2024-04-15 03:29:59

by Barry Song

[permalink] [raw]
Subject: Re: [PATCH] mm: thp: makes the memcg THP deferred split shrinker aware of node_id

On Mon, Apr 15, 2024 at 3:11 PM <[email protected]> wrote:
>
> From: Ran Xiaokai <[email protected]>
>
> Since commit 87eaceb3faa5 ("mm: thp: make deferred split shrinker
> memcg aware"), the THP deferred split queue is per memcg but not
> per mem_cgroup_per_node. This has two aspects of impact:
>
> Impact1: for kswapd reclaim
> =====================
> kswapd
> balance_pgdat
> kswapd_shrink_node
> shrink_node(pgdat, sc);
> shrink_node_memcgs(pgdat, sc);
> shrink_slab(sc->gfp_mask, pgdat->node_id, memcg...);
> the parameter "pgdat->node_id" does not take effectct for
> THP deferred_split_shrinker, as the deferred_split_queue of
> specified memcg is not for a certain numa node but for all the nodes.
> We want to makes the memcg THP deferred split shrinker aware of
> node_id.
>
> Impact2: thp-deferred_split shrinker debugfs interface
> =========================================
> for the "count" file:
> <cgroup inode id> <objects on node 0> <objects on node 1>
> the output is acctually the sum of all numa nodes.
> for the "scan" file:
> <cgroup inode id> <numa id> <number of objects to scan>
> Also the "numa id" input does not take effect here.
>
> This patch makes memcg deferred_split_queue per mem_cgroup_per_node
> so try to conform to semantic logic.

This seems to be a correct fix to me, + Yang Shi, the original author of
commit 87eaceb3faa5.

>
> Reviewed-by: Lu Zhongjun <[email protected]>
> Signed-off-by: Ran Xiaokai <[email protected]>
> Cc: xu xin <[email protected]>
> Cc: Yang Yang <[email protected]>
> ---
> include/linux/memcontrol.h | 7 +++----
> mm/huge_memory.c | 6 +++---
> mm/memcontrol.c | 11 +++++------
> 3 files changed, 11 insertions(+), 13 deletions(-)
>
> diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
> index 394fd0a887ae..7282861d5a5d 100644
> --- a/include/linux/memcontrol.h
> +++ b/include/linux/memcontrol.h
> @@ -130,6 +130,9 @@ struct mem_cgroup_per_node {
> bool on_tree;
> struct mem_cgroup *memcg; /* Back pointer, we cannot */
> /* use container_of */
> +#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> + struct deferred_split deferred_split_queue;
> +#endif
> };
>
> struct mem_cgroup_threshold {
> @@ -327,10 +330,6 @@ struct mem_cgroup {
> struct list_head event_list;
> spinlock_t event_list_lock;
>
> -#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> - struct deferred_split deferred_split_queue;
> -#endif
> -
> #ifdef CONFIG_LRU_GEN_WALKS_MMU
> /* per-memcg mm_struct list */
> struct lru_gen_mm_list mm_list;
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index 9859aa4f7553..338d071070a6 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -774,7 +774,7 @@ struct deferred_split *get_deferred_split_queue(struct folio *folio)
> struct pglist_data *pgdat = NODE_DATA(folio_nid(folio));
>
> if (memcg)
> - return &memcg->deferred_split_queue;
> + return &memcg->nodeinfo[pgdat->node_id]->deferred_split_queue;
> else
> return &pgdat->deferred_split_queue;
> }
> @@ -3305,7 +3305,7 @@ static unsigned long deferred_split_count(struct shrinker *shrink,
>
> #ifdef CONFIG_MEMCG
> if (sc->memcg)
> - ds_queue = &sc->memcg->deferred_split_queue;
> + ds_queue = &sc->memcg->nodeinfo[sc->nid]->deferred_split_queue;
> #endif
> return READ_ONCE(ds_queue->split_queue_len);
> }
> @@ -3322,7 +3322,7 @@ static unsigned long deferred_split_scan(struct shrinker *shrink,
>
> #ifdef CONFIG_MEMCG
> if (sc->memcg)
> - ds_queue = &sc->memcg->deferred_split_queue;
> + ds_queue = &sc->memcg->nodeinfo[sc->nid]->deferred_split_queue;
> #endif
>
> spin_lock_irqsave(&ds_queue->split_queue_lock, flags);
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index fabce2b50c69..cdf9f5fa3b8e 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -5445,7 +5445,11 @@ static int alloc_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node)
> kfree(pn);
> return 1;
> }
> -
> +#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> + spin_lock_init(&pn->deferred_split_queue.split_queue_lock);
> + INIT_LIST_HEAD(&pn->deferred_split_queue.split_queue);
> + pn->deferred_split_queue.split_queue_len = 0;
> +#endif
> lruvec_init(&pn->lruvec);
> pn->memcg = memcg;
>
> @@ -5545,11 +5549,6 @@ static struct mem_cgroup *mem_cgroup_alloc(struct mem_cgroup *parent)
> for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++)
> memcg->cgwb_frn[i].done =
> __WB_COMPLETION_INIT(&memcg_cgwb_frn_waitq);
> -#endif
> -#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> - spin_lock_init(&memcg->deferred_split_queue.split_queue_lock);
> - INIT_LIST_HEAD(&memcg->deferred_split_queue.split_queue);
> - memcg->deferred_split_queue.split_queue_len = 0;
> #endif
> lru_gen_init_memcg(memcg);
> return memcg;
> --
> 2.15.2
>

Thanks
Barry

2024-04-15 18:32:19

by Yang Shi

[permalink] [raw]
Subject: Re: [PATCH] mm: thp: makes the memcg THP deferred split shrinker aware of node_id

On Sun, Apr 14, 2024 at 8:30 PM Barry Song <[email protected]> wrote:
>
> On Mon, Apr 15, 2024 at 3:11 PM <[email protected]> wrote:
> >
> > From: Ran Xiaokai <[email protected]>
> >
> > Since commit 87eaceb3faa5 ("mm: thp: make deferred split shrinker
> > memcg aware"), the THP deferred split queue is per memcg but not
> > per mem_cgroup_per_node. This has two aspects of impact:
> >
> > Impact1: for kswapd reclaim
> > =====================
> > kswapd
> > balance_pgdat
> > kswapd_shrink_node
> > shrink_node(pgdat, sc);
> > shrink_node_memcgs(pgdat, sc);
> > shrink_slab(sc->gfp_mask, pgdat->node_id, memcg...);
> > the parameter "pgdat->node_id" does not take effectct for
> > THP deferred_split_shrinker, as the deferred_split_queue of
> > specified memcg is not for a certain numa node but for all the nodes.
> > We want to makes the memcg THP deferred split shrinker aware of
> > node_id.
> >
> > Impact2: thp-deferred_split shrinker debugfs interface
> > =========================================
> > for the "count" file:
> > <cgroup inode id> <objects on node 0> <objects on node 1>
> > the output is acctually the sum of all numa nodes.
> > for the "scan" file:
> > <cgroup inode id> <numa id> <number of objects to scan>
> > Also the "numa id" input does not take effect here.
> >
> > This patch makes memcg deferred_split_queue per mem_cgroup_per_node
> > so try to conform to semantic logic.

I used to have a similar patch before,
https://lore.kernel.org/linux-mm/[email protected]/

But it was somehow lost in discussion.

I have no objection to this patch. However, I was thinking about using
list_lru for deferred split queue, but I didn't have time to look
deeper. Maybe we should try now?

>
> This seems to be a correct fix to me, + Yang Shi, the original author of
> commit 87eaceb3faa5.
>
> >
> > Reviewed-by: Lu Zhongjun <[email protected]>
> > Signed-off-by: Ran Xiaokai <[email protected]>
> > Cc: xu xin <[email protected]>
> > Cc: Yang Yang <[email protected]>
> > ---
> > include/linux/memcontrol.h | 7 +++----
> > mm/huge_memory.c | 6 +++---
> > mm/memcontrol.c | 11 +++++------
> > 3 files changed, 11 insertions(+), 13 deletions(-)
> >
> > diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
> > index 394fd0a887ae..7282861d5a5d 100644
> > --- a/include/linux/memcontrol.h
> > +++ b/include/linux/memcontrol.h
> > @@ -130,6 +130,9 @@ struct mem_cgroup_per_node {
> > bool on_tree;
> > struct mem_cgroup *memcg; /* Back pointer, we cannot */
> > /* use container_of */
> > +#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> > + struct deferred_split deferred_split_queue;
> > +#endif
> > };
> >
> > struct mem_cgroup_threshold {
> > @@ -327,10 +330,6 @@ struct mem_cgroup {
> > struct list_head event_list;
> > spinlock_t event_list_lock;
> >
> > -#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> > - struct deferred_split deferred_split_queue;
> > -#endif
> > -
> > #ifdef CONFIG_LRU_GEN_WALKS_MMU
> > /* per-memcg mm_struct list */
> > struct lru_gen_mm_list mm_list;
> > diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> > index 9859aa4f7553..338d071070a6 100644
> > --- a/mm/huge_memory.c
> > +++ b/mm/huge_memory.c
> > @@ -774,7 +774,7 @@ struct deferred_split *get_deferred_split_queue(struct folio *folio)
> > struct pglist_data *pgdat = NODE_DATA(folio_nid(folio));
> >
> > if (memcg)
> > - return &memcg->deferred_split_queue;
> > + return &memcg->nodeinfo[pgdat->node_id]->deferred_split_queue;
> > else
> > return &pgdat->deferred_split_queue;
> > }
> > @@ -3305,7 +3305,7 @@ static unsigned long deferred_split_count(struct shrinker *shrink,
> >
> > #ifdef CONFIG_MEMCG
> > if (sc->memcg)
> > - ds_queue = &sc->memcg->deferred_split_queue;
> > + ds_queue = &sc->memcg->nodeinfo[sc->nid]->deferred_split_queue;
> > #endif
> > return READ_ONCE(ds_queue->split_queue_len);
> > }
> > @@ -3322,7 +3322,7 @@ static unsigned long deferred_split_scan(struct shrinker *shrink,
> >
> > #ifdef CONFIG_MEMCG
> > if (sc->memcg)
> > - ds_queue = &sc->memcg->deferred_split_queue;
> > + ds_queue = &sc->memcg->nodeinfo[sc->nid]->deferred_split_queue;
> > #endif
> >
> > spin_lock_irqsave(&ds_queue->split_queue_lock, flags);
> > diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> > index fabce2b50c69..cdf9f5fa3b8e 100644
> > --- a/mm/memcontrol.c
> > +++ b/mm/memcontrol.c
> > @@ -5445,7 +5445,11 @@ static int alloc_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node)
> > kfree(pn);
> > return 1;
> > }
> > -
> > +#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> > + spin_lock_init(&pn->deferred_split_queue.split_queue_lock);
> > + INIT_LIST_HEAD(&pn->deferred_split_queue.split_queue);
> > + pn->deferred_split_queue.split_queue_len = 0;
> > +#endif
> > lruvec_init(&pn->lruvec);
> > pn->memcg = memcg;
> >
> > @@ -5545,11 +5549,6 @@ static struct mem_cgroup *mem_cgroup_alloc(struct mem_cgroup *parent)
> > for (i = 0; i < MEMCG_CGWB_FRN_CNT; i++)
> > memcg->cgwb_frn[i].done =
> > __WB_COMPLETION_INIT(&memcg_cgwb_frn_waitq);
> > -#endif
> > -#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> > - spin_lock_init(&memcg->deferred_split_queue.split_queue_lock);
> > - INIT_LIST_HEAD(&memcg->deferred_split_queue.split_queue);
> > - memcg->deferred_split_queue.split_queue_len = 0;
> > #endif
> > lru_gen_init_memcg(memcg);
> > return memcg;
> > --
> > 2.15.2
> >
>
> Thanks
> Barry
>