* RE: [PATCH v2] vmscan: add a vmscan event for reclaim_pages
[not found] <CGME20241011124931epcas1p176b2ce6a566f7557468dff1e12677a11@epcms1p6>
@ 2024-10-16 13:24 ` 김재원
2024-10-17 9:20 ` Vlastimil Babka
0 siblings, 1 reply; 5+ messages in thread
From: 김재원 @ 2024-10-16 13:24 UTC (permalink / raw)
To: Vlastimil Babka, 김재원,
sj, minchan, kaleshsingh, akpm
Cc: linux-mm, linux-kernel, jaewon31.kim
>On 10/11/24 14:49, Jaewon Kim wrote:
>> The reclaim_folio_list uses a dummy reclaim_stat and is not being
>> used. To know the memory stat, add a new trace event. This is useful how
>> how many pages are not reclaimed or why.
>>
>> This is an example.
>> mm_vmscan_reclaim_pages: nid=0 nr_scanned=112 nr_reclaimed=112 nr_dirty=0 nr_writeback=0 nr_congested=0 nr_immediate=0 nr_activate_anon=0 nr_activate_file=0 nr_ref_keep=0 nr_unmap_fail=0
>>
>> Currenlty reclaim_folio_list is only called by reclaim_pages, and
>> reclaim_pages is used by damon and madvise. In the latest Android,
>> reclaim_pages is also used by shmem to reclaim all pages in a
>> address_space.
>>
>> Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com>
>> ---
>> v2: remove reclaim_stat_add function and call the trace on each node
>> v1: introduce a new trace event
>> ---
>> include/trace/events/vmscan.h | 45 +++++++++++++++++++++++++++++++++++
>> mm/vmscan.c | 16 +++++++++----
>> 2 files changed, 56 insertions(+), 5 deletions(-)
>>
>> diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
>> index 1a488c30afa5..490958fa10de 100644
>> --- a/include/trace/events/vmscan.h
>> +++ b/include/trace/events/vmscan.h
>> @@ -346,6 +346,51 @@ TRACE_EVENT(mm_vmscan_write_folio,
>> show_reclaim_flags(__entry->reclaim_flags))
>> );
>>
>> +TRACE_EVENT(mm_vmscan_reclaim_pages,
>> +
>> + TP_PROTO(int nid,
>> + unsigned long nr_scanned, unsigned long nr_reclaimed,
>> + struct reclaim_stat *stat),
>> +
>> + TP_ARGS(nid, nr_scanned, nr_reclaimed, stat),
>> +
>> + TP_STRUCT__entry(
>> + __field(int, nid)
>> + __field(unsigned long, nr_scanned)
>> + __field(unsigned long, nr_reclaimed)
>> + __field(unsigned long, nr_dirty)
>> + __field(unsigned long, nr_writeback)
>> + __field(unsigned long, nr_congested)
>> + __field(unsigned long, nr_immediate)
>> + __field(unsigned int, nr_activate0)
>> + __field(unsigned int, nr_activate1)
>> + __field(unsigned long, nr_ref_keep)
>> + __field(unsigned long, nr_unmap_fail)
>> + ),
>> +
>> + TP_fast_assign(
>> + __entry->nid = nid;
>> + __entry->nr_scanned = nr_scanned;
>> + __entry->nr_reclaimed = nr_reclaimed;
>> + __entry->nr_dirty = stat->nr_dirty;
>> + __entry->nr_writeback = stat->nr_writeback;
>> + __entry->nr_congested = stat->nr_congested;
>> + __entry->nr_immediate = stat->nr_immediate;
>> + __entry->nr_activate0 = stat->nr_activate[0];
>> + __entry->nr_activate1 = stat->nr_activate[1];
>> + __entry->nr_ref_keep = stat->nr_ref_keep;
>> + __entry->nr_unmap_fail = stat->nr_unmap_fail;
>> + ),
>> +
>> + TP_printk("nid=%d nr_scanned=%ld nr_reclaimed=%ld nr_dirty=%ld nr_writeback=%ld nr_congested=%ld nr_immediate=%ld nr_activate_anon=%d nr_activate_file=%d nr_ref_keep=%ld nr_unmap_fail=%ld",
>> + __entry->nid,
>> + __entry->nr_scanned, __entry->nr_reclaimed,
>> + __entry->nr_dirty, __entry->nr_writeback,
>> + __entry->nr_congested, __entry->nr_immediate,
>> + __entry->nr_activate0, __entry->nr_activate1,
>> + __entry->nr_ref_keep, __entry->nr_unmap_fail)
>> +);
>> +
>> TRACE_EVENT(mm_vmscan_lru_shrink_inactive,
>>
>> TP_PROTO(int nid,
>> diff --git a/mm/vmscan.c b/mm/vmscan.c
>> index 749cdc110c74..0c2c36bf4c5a 100644
>> --- a/mm/vmscan.c
>> +++ b/mm/vmscan.c
>> @@ -2126,9 +2126,10 @@ static void shrink_active_list(unsigned long nr_to_scan,
>> }
>>
>> static unsigned int reclaim_folio_list(struct list_head *folio_list,
>> + unsigned int nr_scanned,
>> struct pglist_data *pgdat)
>> {
>> - struct reclaim_stat dummy_stat;
>> + struct reclaim_stat stat;
>> unsigned int nr_reclaimed;
>> struct folio *folio;
>> struct scan_control sc = {
>> @@ -2139,12 +2140,13 @@ static unsigned int reclaim_folio_list(struct list_head *folio_list,
>> .no_demotion = 1,
>> };
>>
>> - nr_reclaimed = shrink_folio_list(folio_list, pgdat, &sc, &dummy_stat, true);
>> + nr_reclaimed = shrink_folio_list(folio_list, pgdat, &sc, &stat, true);
>> while (!list_empty(folio_list)) {
>> folio = lru_to_folio(folio_list);
>> list_del(&folio->lru);
>> folio_putback_lru(folio);
>> }
>> + trace_mm_vmscan_reclaim_pages(pgdat->node_id, nr_scanned, nr_reclaimed, &stat);
>
>Why is the new calculation of nr_scanned needed? Could you just take a delta
>of sc->nr_scanned, i.e. after - before calling shrink_folio_list() ?
Oh correct.
Except the case of (!folio_trylock(folio)), shrink_folio_list would count on sc->nr_scanned.
I don't understand why we do not count this lock case though.
Let me try to change as you suggested.
I think without 'after - before', we can just use sc->nr_scanned after shrink_folio_list.
Thank you
>
>>
>> return nr_reclaimed;
>> }
>> @@ -2152,6 +2154,7 @@ static unsigned int reclaim_folio_list(struct list_head *folio_list,
>> unsigned long reclaim_pages(struct list_head *folio_list)
>> {
>> int nid;
>> + unsigned int nr_scanned = 0;
>> unsigned int nr_reclaimed = 0;
>> LIST_HEAD(node_folio_list);
>> unsigned int noreclaim_flag;
>> @@ -2168,15 +2171,18 @@ unsigned long reclaim_pages(struct list_head *folio_list)
>> if (nid == folio_nid(folio)) {
>> folio_clear_active(folio);
>> list_move(&folio->lru, &node_folio_list);
>> + nr_scanned += folio_nr_pages(folio);
>> continue;
>> }
>>
>> - nr_reclaimed += reclaim_folio_list(&node_folio_list, NODE_DATA(nid));
>> + nr_reclaimed += reclaim_folio_list(&node_folio_list, nr_scanned,
>> + NODE_DATA(nid));
>> + nr_scanned = 0;
>> nid = folio_nid(lru_to_folio(folio_list));
>> } while (!list_empty(folio_list));
>>
>> - nr_reclaimed += reclaim_folio_list(&node_folio_list, NODE_DATA(nid));
>> -
>> + nr_reclaimed += reclaim_folio_list(&node_folio_list, nr_scanned,
>> + NODE_DATA(nid));
>> memalloc_noreclaim_restore(noreclaim_flag);
>>
>> return nr_reclaimed;
>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v2] vmscan: add a vmscan event for reclaim_pages
2024-10-16 13:24 ` [PATCH v2] vmscan: add a vmscan event for reclaim_pages 김재원
@ 2024-10-17 9:20 ` Vlastimil Babka
0 siblings, 0 replies; 5+ messages in thread
From: Vlastimil Babka @ 2024-10-17 9:20 UTC (permalink / raw)
To: jaewon31.kim, sj, minchan, kaleshsingh, akpm
Cc: linux-mm, linux-kernel, jaewon31.kim
On 10/16/24 15:24, 김재원 wrote:
>>On 10/11/24 14:49, Jaewon Kim wrote:
>>> The reclaim_folio_list uses a dummy reclaim_stat and is not being
>>> used. To know the memory stat, add a new trace event. This is useful how
>>> how many pages are not reclaimed or why.
>>>
>>> This is an example.
>>> mm_vmscan_reclaim_pages: nid=0 nr_scanned=112 nr_reclaimed=112 nr_dirty=0 nr_writeback=0 nr_congested=0 nr_immediate=0 nr_activate_anon=0 nr_activate_file=0 nr_ref_keep=0 nr_unmap_fail=0
>>>
>>> Currenlty reclaim_folio_list is only called by reclaim_pages, and
>>> reclaim_pages is used by damon and madvise. In the latest Android,
>>> reclaim_pages is also used by shmem to reclaim all pages in a
>>> address_space.
>>>
>>> Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com>
>>> ---
>>> v2: remove reclaim_stat_add function and call the trace on each node
>>> v1: introduce a new trace event
>>> ---
>>> include/trace/events/vmscan.h | 45 +++++++++++++++++++++++++++++++++++
>>> mm/vmscan.c | 16 +++++++++----
>>> 2 files changed, 56 insertions(+), 5 deletions(-)
>>>
>>> diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
>>> index 1a488c30afa5..490958fa10de 100644
>>> --- a/include/trace/events/vmscan.h
>>> +++ b/include/trace/events/vmscan.h
>>> @@ -346,6 +346,51 @@ TRACE_EVENT(mm_vmscan_write_folio,
>>> show_reclaim_flags(__entry->reclaim_flags))
>>> );
>>>
>>> +TRACE_EVENT(mm_vmscan_reclaim_pages,
>>> +
>>> + TP_PROTO(int nid,
>>> + unsigned long nr_scanned, unsigned long nr_reclaimed,
>>> + struct reclaim_stat *stat),
>>> +
>>> + TP_ARGS(nid, nr_scanned, nr_reclaimed, stat),
>>> +
>>> + TP_STRUCT__entry(
>>> + __field(int, nid)
>>> + __field(unsigned long, nr_scanned)
>>> + __field(unsigned long, nr_reclaimed)
>>> + __field(unsigned long, nr_dirty)
>>> + __field(unsigned long, nr_writeback)
>>> + __field(unsigned long, nr_congested)
>>> + __field(unsigned long, nr_immediate)
>>> + __field(unsigned int, nr_activate0)
>>> + __field(unsigned int, nr_activate1)
>>> + __field(unsigned long, nr_ref_keep)
>>> + __field(unsigned long, nr_unmap_fail)
>>> + ),
>>> +
>>> + TP_fast_assign(
>>> + __entry->nid = nid;
>>> + __entry->nr_scanned = nr_scanned;
>>> + __entry->nr_reclaimed = nr_reclaimed;
>>> + __entry->nr_dirty = stat->nr_dirty;
>>> + __entry->nr_writeback = stat->nr_writeback;
>>> + __entry->nr_congested = stat->nr_congested;
>>> + __entry->nr_immediate = stat->nr_immediate;
>>> + __entry->nr_activate0 = stat->nr_activate[0];
>>> + __entry->nr_activate1 = stat->nr_activate[1];
>>> + __entry->nr_ref_keep = stat->nr_ref_keep;
>>> + __entry->nr_unmap_fail = stat->nr_unmap_fail;
>>> + ),
>>> +
>>> + TP_printk("nid=%d nr_scanned=%ld nr_reclaimed=%ld nr_dirty=%ld nr_writeback=%ld nr_congested=%ld nr_immediate=%ld nr_activate_anon=%d nr_activate_file=%d nr_ref_keep=%ld nr_unmap_fail=%ld",
>>> + __entry->nid,
>>> + __entry->nr_scanned, __entry->nr_reclaimed,
>>> + __entry->nr_dirty, __entry->nr_writeback,
>>> + __entry->nr_congested, __entry->nr_immediate,
>>> + __entry->nr_activate0, __entry->nr_activate1,
>>> + __entry->nr_ref_keep, __entry->nr_unmap_fail)
>>> +);
>>> +
>>> TRACE_EVENT(mm_vmscan_lru_shrink_inactive,
>>>
>>> TP_PROTO(int nid,
>>> diff --git a/mm/vmscan.c b/mm/vmscan.c
>>> index 749cdc110c74..0c2c36bf4c5a 100644
>>> --- a/mm/vmscan.c
>>> +++ b/mm/vmscan.c
>>> @@ -2126,9 +2126,10 @@ static void shrink_active_list(unsigned long nr_to_scan,
>>> }
>>>
>>> static unsigned int reclaim_folio_list(struct list_head *folio_list,
>>> + unsigned int nr_scanned,
>>> struct pglist_data *pgdat)
>>> {
>>> - struct reclaim_stat dummy_stat;
>>> + struct reclaim_stat stat;
>>> unsigned int nr_reclaimed;
>>> struct folio *folio;
>>> struct scan_control sc = {
>>> @@ -2139,12 +2140,13 @@ static unsigned int reclaim_folio_list(struct list_head *folio_list,
>>> .no_demotion = 1,
>>> };
>>>
>>> - nr_reclaimed = shrink_folio_list(folio_list, pgdat, &sc, &dummy_stat, true);
>>> + nr_reclaimed = shrink_folio_list(folio_list, pgdat, &sc, &stat, true);
>>> while (!list_empty(folio_list)) {
>>> folio = lru_to_folio(folio_list);
>>> list_del(&folio->lru);
>>> folio_putback_lru(folio);
>>> }
>>> + trace_mm_vmscan_reclaim_pages(pgdat->node_id, nr_scanned, nr_reclaimed, &stat);
>>
>>Why is the new calculation of nr_scanned needed? Could you just take a delta
>>of sc->nr_scanned, i.e. after - before calling shrink_folio_list() ?
>
> Oh correct.
>
> Except the case of (!folio_trylock(folio)), shrink_folio_list would count on sc->nr_scanned.
> I don't understand why we do not count this lock case though.
Guess it means we couldn't really scan it. Should be probably rare anyway.
^ permalink raw reply [flat|nested] 5+ messages in thread
* RE: [PATCH v2] vmscan: add a vmscan event for reclaim_pages
[not found] ` <CGME20241011124931epcas1p176b2ce6a566f7557468dff1e12677a11@epcms1p3>
@ 2024-10-16 13:22 ` Jaewon Kim
0 siblings, 0 replies; 5+ messages in thread
From: Jaewon Kim @ 2024-10-16 13:22 UTC (permalink / raw)
>On 10/11/24 14:49, Jaewon Kim wrote:
>> The reclaim_folio_list uses a dummy reclaim_stat and is not being
>> used. To know the memory stat, add a new trace event. This is useful how
>> how many pages are not reclaimed or why.
>>
>> This is an example.
>> mm_vmscan_reclaim_pages: nid=0 nr_scanned=112 nr_reclaimed=112 nr_dirty=0 nr_writeback=0 nr_congested=0 nr_immediate=0 nr_activate_anon=0 nr_activate_file=0 nr_ref_keep=0 nr_unmap_fail=0
>>
>> Currenlty reclaim_folio_list is only called by reclaim_pages, and
>> reclaim_pages is used by damon and madvise. In the latest Android,
>> reclaim_pages is also used by shmem to reclaim all pages in a
>> address_space.
>>
>> Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com>
>> ---
>> v2: remove reclaim_stat_add function and call the trace on each node
>> v1: introduce a new trace event
>> ---
>> include/trace/events/vmscan.h | 45 +++++++++++++++++++++++++++++++++++
>> mm/vmscan.c | 16 +++++++++----
>> 2 files changed, 56 insertions(+), 5 deletions(-)
>>
>> diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
>> index 1a488c30afa5..490958fa10de 100644
>> --- a/include/trace/events/vmscan.h
>> +++ b/include/trace/events/vmscan.h
>> @@ -346,6 +346,51 @@ TRACE_EVENT(mm_vmscan_write_folio,
>> show_reclaim_flags(__entry->reclaim_flags))
>> );
>>
>> +TRACE_EVENT(mm_vmscan_reclaim_pages,
>> +
>> + TP_PROTO(int nid,
>> + unsigned long nr_scanned, unsigned long nr_reclaimed,
>> + struct reclaim_stat *stat),
>> +
>> + TP_ARGS(nid, nr_scanned, nr_reclaimed, stat),
>> +
>> + TP_STRUCT__entry(
>> + __field(int, nid)
>> + __field(unsigned long, nr_scanned)
>> + __field(unsigned long, nr_reclaimed)
>> + __field(unsigned long, nr_dirty)
>> + __field(unsigned long, nr_writeback)
>> + __field(unsigned long, nr_congested)
>> + __field(unsigned long, nr_immediate)
>> + __field(unsigned int, nr_activate0)
>> + __field(unsigned int, nr_activate1)
>> + __field(unsigned long, nr_ref_keep)
>> + __field(unsigned long, nr_unmap_fail)
>> + ),
>> +
>> + TP_fast_assign(
>> + __entry->nid = nid;
>> + __entry->nr_scanned = nr_scanned;
>> + __entry->nr_reclaimed = nr_reclaimed;
>> + __entry->nr_dirty = stat->nr_dirty;
>> + __entry->nr_writeback = stat->nr_writeback;
>> + __entry->nr_congested = stat->nr_congested;
>> + __entry->nr_immediate = stat->nr_immediate;
>> + __entry->nr_activate0 = stat->nr_activate[0];
>> + __entry->nr_activate1 = stat->nr_activate[1];
>> + __entry->nr_ref_keep = stat->nr_ref_keep;
>> + __entry->nr_unmap_fail = stat->nr_unmap_fail;
>> + ),
>> +
>> + TP_printk("nid=%d nr_scanned=%ld nr_reclaimed=%ld nr_dirty=%ld nr_writeback=%ld nr_congested=%ld nr_immediate=%ld nr_activate_anon=%d nr_activate_file=%d nr_ref_keep=%ld nr_unmap_fail=%ld",
>> + __entry->nid,
>> + __entry->nr_scanned, __entry->nr_reclaimed,
>> + __entry->nr_dirty, __entry->nr_writeback,
>> + __entry->nr_congested, __entry->nr_immediate,
>> + __entry->nr_activate0, __entry->nr_activate1,
>> + __entry->nr_ref_keep, __entry->nr_unmap_fail)
>> +);
>> +
>> TRACE_EVENT(mm_vmscan_lru_shrink_inactive,
>>
>> TP_PROTO(int nid,
>> diff --git a/mm/vmscan.c b/mm/vmscan.c
>> index 749cdc110c74..0c2c36bf4c5a 100644
>> --- a/mm/vmscan.c
>> +++ b/mm/vmscan.c
>> @@ -2126,9 +2126,10 @@ static void shrink_active_list(unsigned long nr_to_scan,
>> }
>>
>> static unsigned int reclaim_folio_list(struct list_head *folio_list,
>> + unsigned int nr_scanned,
>> struct pglist_data *pgdat)
>> {
>> - struct reclaim_stat dummy_stat;
>> + struct reclaim_stat stat;
>> unsigned int nr_reclaimed;
>> struct folio *folio;
>> struct scan_control sc = {
>> @@ -2139,12 +2140,13 @@ static unsigned int reclaim_folio_list(struct list_head *folio_list,
>> .no_demotion = 1,
>> };
>>
>> - nr_reclaimed = shrink_folio_list(folio_list, pgdat, &sc, &dummy_stat, true);
>> + nr_reclaimed = shrink_folio_list(folio_list, pgdat, &sc, &stat, true);
>> while (!list_empty(folio_list)) {
>> folio = lru_to_folio(folio_list);
>> list_del(&folio->lru);
>> folio_putback_lru(folio);
>> }
>> + trace_mm_vmscan_reclaim_pages(pgdat->node_id, nr_scanned, nr_reclaimed, &stat);
>
>Why is the new calculation of nr_scanned needed? Could you just take a delta
>of sc->nr_scanned, i.e. after - before calling shrink_folio_list() ?
Oh correct.
Except the case of (!folio_trylock(folio)), shrink_folio_list would count at sc->nr_scanned.
I don't understand why we do not count this lock case though.
Let me try to change as you suggested.
I think without 'after - before', we can just use sc->nr_scanned after shrink_folio_list.
Thank you
>
>>
>> return nr_reclaimed;
>> }
>> @@ -2152,6 +2154,7 @@ static unsigned int reclaim_folio_list(struct list_head *folio_list,
>> unsigned long reclaim_pages(struct list_head *folio_list)
>> {
>> int nid;
>> + unsigned int nr_scanned = 0;
>> unsigned int nr_reclaimed = 0;
>> LIST_HEAD(node_folio_list);
>> unsigned int noreclaim_flag;
>> @@ -2168,15 +2171,18 @@ unsigned long reclaim_pages(struct list_head *folio_list)
>> if (nid == folio_nid(folio)) {
>> folio_clear_active(folio);
>> list_move(&folio->lru, &node_folio_list);
>> + nr_scanned += folio_nr_pages(folio);
>> continue;
>> }
>>
>> - nr_reclaimed += reclaim_folio_list(&node_folio_list, NODE_DATA(nid));
>> + nr_reclaimed += reclaim_folio_list(&node_folio_list, nr_scanned,
>> + NODE_DATA(nid));
>> + nr_scanned = 0;
>> nid = folio_nid(lru_to_folio(folio_list));
>> } while (!list_empty(folio_list));
>>
>> - nr_reclaimed += reclaim_folio_list(&node_folio_list, NODE_DATA(nid));
>> -
>> + nr_reclaimed += reclaim_folio_list(&node_folio_list, nr_scanned,
>> + NODE_DATA(nid));
>> memalloc_noreclaim_restore(noreclaim_flag);
>>
>> return nr_reclaimed;
>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v2] vmscan: add a vmscan event for reclaim_pages
2024-10-11 12:49 ` Jaewon Kim
@ 2024-10-16 13:03 ` Vlastimil Babka
[not found] ` <CGME20241011124931epcas1p176b2ce6a566f7557468dff1e12677a11@epcms1p3>
1 sibling, 0 replies; 5+ messages in thread
From: Vlastimil Babka @ 2024-10-16 13:03 UTC (permalink / raw)
To: Jaewon Kim, sj, minchan, kaleshsingh, akpm
Cc: linux-mm, linux-kernel, jaewon31.kim
On 10/11/24 14:49, Jaewon Kim wrote:
> The reclaim_folio_list uses a dummy reclaim_stat and is not being
> used. To know the memory stat, add a new trace event. This is useful how
> how many pages are not reclaimed or why.
>
> This is an example.
> mm_vmscan_reclaim_pages: nid=0 nr_scanned=112 nr_reclaimed=112 nr_dirty=0 nr_writeback=0 nr_congested=0 nr_immediate=0 nr_activate_anon=0 nr_activate_file=0 nr_ref_keep=0 nr_unmap_fail=0
>
> Currenlty reclaim_folio_list is only called by reclaim_pages, and
> reclaim_pages is used by damon and madvise. In the latest Android,
> reclaim_pages is also used by shmem to reclaim all pages in a
> address_space.
>
> Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com>
> ---
> v2: remove reclaim_stat_add function and call the trace on each node
> v1: introduce a new trace event
> ---
> include/trace/events/vmscan.h | 45 +++++++++++++++++++++++++++++++++++
> mm/vmscan.c | 16 +++++++++----
> 2 files changed, 56 insertions(+), 5 deletions(-)
>
> diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
> index 1a488c30afa5..490958fa10de 100644
> --- a/include/trace/events/vmscan.h
> +++ b/include/trace/events/vmscan.h
> @@ -346,6 +346,51 @@ TRACE_EVENT(mm_vmscan_write_folio,
> show_reclaim_flags(__entry->reclaim_flags))
> );
>
> +TRACE_EVENT(mm_vmscan_reclaim_pages,
> +
> + TP_PROTO(int nid,
> + unsigned long nr_scanned, unsigned long nr_reclaimed,
> + struct reclaim_stat *stat),
> +
> + TP_ARGS(nid, nr_scanned, nr_reclaimed, stat),
> +
> + TP_STRUCT__entry(
> + __field(int, nid)
> + __field(unsigned long, nr_scanned)
> + __field(unsigned long, nr_reclaimed)
> + __field(unsigned long, nr_dirty)
> + __field(unsigned long, nr_writeback)
> + __field(unsigned long, nr_congested)
> + __field(unsigned long, nr_immediate)
> + __field(unsigned int, nr_activate0)
> + __field(unsigned int, nr_activate1)
> + __field(unsigned long, nr_ref_keep)
> + __field(unsigned long, nr_unmap_fail)
> + ),
> +
> + TP_fast_assign(
> + __entry->nid = nid;
> + __entry->nr_scanned = nr_scanned;
> + __entry->nr_reclaimed = nr_reclaimed;
> + __entry->nr_dirty = stat->nr_dirty;
> + __entry->nr_writeback = stat->nr_writeback;
> + __entry->nr_congested = stat->nr_congested;
> + __entry->nr_immediate = stat->nr_immediate;
> + __entry->nr_activate0 = stat->nr_activate[0];
> + __entry->nr_activate1 = stat->nr_activate[1];
> + __entry->nr_ref_keep = stat->nr_ref_keep;
> + __entry->nr_unmap_fail = stat->nr_unmap_fail;
> + ),
> +
> + TP_printk("nid=%d nr_scanned=%ld nr_reclaimed=%ld nr_dirty=%ld nr_writeback=%ld nr_congested=%ld nr_immediate=%ld nr_activate_anon=%d nr_activate_file=%d nr_ref_keep=%ld nr_unmap_fail=%ld",
> + __entry->nid,
> + __entry->nr_scanned, __entry->nr_reclaimed,
> + __entry->nr_dirty, __entry->nr_writeback,
> + __entry->nr_congested, __entry->nr_immediate,
> + __entry->nr_activate0, __entry->nr_activate1,
> + __entry->nr_ref_keep, __entry->nr_unmap_fail)
> +);
> +
> TRACE_EVENT(mm_vmscan_lru_shrink_inactive,
>
> TP_PROTO(int nid,
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index 749cdc110c74..0c2c36bf4c5a 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -2126,9 +2126,10 @@ static void shrink_active_list(unsigned long nr_to_scan,
> }
>
> static unsigned int reclaim_folio_list(struct list_head *folio_list,
> + unsigned int nr_scanned,
> struct pglist_data *pgdat)
> {
> - struct reclaim_stat dummy_stat;
> + struct reclaim_stat stat;
> unsigned int nr_reclaimed;
> struct folio *folio;
> struct scan_control sc = {
> @@ -2139,12 +2140,13 @@ static unsigned int reclaim_folio_list(struct list_head *folio_list,
> .no_demotion = 1,
> };
>
> - nr_reclaimed = shrink_folio_list(folio_list, pgdat, &sc, &dummy_stat, true);
> + nr_reclaimed = shrink_folio_list(folio_list, pgdat, &sc, &stat, true);
> while (!list_empty(folio_list)) {
> folio = lru_to_folio(folio_list);
> list_del(&folio->lru);
> folio_putback_lru(folio);
> }
> + trace_mm_vmscan_reclaim_pages(pgdat->node_id, nr_scanned, nr_reclaimed, &stat);
Why is the new calculation of nr_scanned needed? Could you just take a delta
of sc->nr_scanned, i.e. after - before calling shrink_folio_list() ?
>
> return nr_reclaimed;
> }
> @@ -2152,6 +2154,7 @@ static unsigned int reclaim_folio_list(struct list_head *folio_list,
> unsigned long reclaim_pages(struct list_head *folio_list)
> {
> int nid;
> + unsigned int nr_scanned = 0;
> unsigned int nr_reclaimed = 0;
> LIST_HEAD(node_folio_list);
> unsigned int noreclaim_flag;
> @@ -2168,15 +2171,18 @@ unsigned long reclaim_pages(struct list_head *folio_list)
> if (nid == folio_nid(folio)) {
> folio_clear_active(folio);
> list_move(&folio->lru, &node_folio_list);
> + nr_scanned += folio_nr_pages(folio);
> continue;
> }
>
> - nr_reclaimed += reclaim_folio_list(&node_folio_list, NODE_DATA(nid));
> + nr_reclaimed += reclaim_folio_list(&node_folio_list, nr_scanned,
> + NODE_DATA(nid));
> + nr_scanned = 0;
> nid = folio_nid(lru_to_folio(folio_list));
> } while (!list_empty(folio_list));
>
> - nr_reclaimed += reclaim_folio_list(&node_folio_list, NODE_DATA(nid));
> -
> + nr_reclaimed += reclaim_folio_list(&node_folio_list, nr_scanned,
> + NODE_DATA(nid));
> memalloc_noreclaim_restore(noreclaim_flag);
>
> return nr_reclaimed;
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH v2] vmscan: add a vmscan event for reclaim_pages
[not found] <CGME20241011124931epcas1p176b2ce6a566f7557468dff1e12677a11@epcas1p1.samsung.com>
@ 2024-10-11 12:49 ` Jaewon Kim
2024-10-16 13:03 ` Vlastimil Babka
[not found] ` <CGME20241011124931epcas1p176b2ce6a566f7557468dff1e12677a11@epcms1p3>
0 siblings, 2 replies; 5+ messages in thread
From: Jaewon Kim @ 2024-10-11 12:49 UTC (permalink / raw)
To: sj, minchan, vbabka, kaleshsingh, akpm
Cc: linux-mm, linux-kernel, jaewon31.kim, Jaewon Kim
The reclaim_folio_list uses a dummy reclaim_stat and is not being
used. To know the memory stat, add a new trace event. This is useful how
how many pages are not reclaimed or why.
This is an example.
mm_vmscan_reclaim_pages: nid=0 nr_scanned=112 nr_reclaimed=112 nr_dirty=0 nr_writeback=0 nr_congested=0 nr_immediate=0 nr_activate_anon=0 nr_activate_file=0 nr_ref_keep=0 nr_unmap_fail=0
Currenlty reclaim_folio_list is only called by reclaim_pages, and
reclaim_pages is used by damon and madvise. In the latest Android,
reclaim_pages is also used by shmem to reclaim all pages in a
address_space.
Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com>
---
v2: remove reclaim_stat_add function and call the trace on each node
v1: introduce a new trace event
---
include/trace/events/vmscan.h | 45 +++++++++++++++++++++++++++++++++++
mm/vmscan.c | 16 +++++++++----
2 files changed, 56 insertions(+), 5 deletions(-)
diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
index 1a488c30afa5..490958fa10de 100644
--- a/include/trace/events/vmscan.h
+++ b/include/trace/events/vmscan.h
@@ -346,6 +346,51 @@ TRACE_EVENT(mm_vmscan_write_folio,
show_reclaim_flags(__entry->reclaim_flags))
);
+TRACE_EVENT(mm_vmscan_reclaim_pages,
+
+ TP_PROTO(int nid,
+ unsigned long nr_scanned, unsigned long nr_reclaimed,
+ struct reclaim_stat *stat),
+
+ TP_ARGS(nid, nr_scanned, nr_reclaimed, stat),
+
+ TP_STRUCT__entry(
+ __field(int, nid)
+ __field(unsigned long, nr_scanned)
+ __field(unsigned long, nr_reclaimed)
+ __field(unsigned long, nr_dirty)
+ __field(unsigned long, nr_writeback)
+ __field(unsigned long, nr_congested)
+ __field(unsigned long, nr_immediate)
+ __field(unsigned int, nr_activate0)
+ __field(unsigned int, nr_activate1)
+ __field(unsigned long, nr_ref_keep)
+ __field(unsigned long, nr_unmap_fail)
+ ),
+
+ TP_fast_assign(
+ __entry->nid = nid;
+ __entry->nr_scanned = nr_scanned;
+ __entry->nr_reclaimed = nr_reclaimed;
+ __entry->nr_dirty = stat->nr_dirty;
+ __entry->nr_writeback = stat->nr_writeback;
+ __entry->nr_congested = stat->nr_congested;
+ __entry->nr_immediate = stat->nr_immediate;
+ __entry->nr_activate0 = stat->nr_activate[0];
+ __entry->nr_activate1 = stat->nr_activate[1];
+ __entry->nr_ref_keep = stat->nr_ref_keep;
+ __entry->nr_unmap_fail = stat->nr_unmap_fail;
+ ),
+
+ TP_printk("nid=%d nr_scanned=%ld nr_reclaimed=%ld nr_dirty=%ld nr_writeback=%ld nr_congested=%ld nr_immediate=%ld nr_activate_anon=%d nr_activate_file=%d nr_ref_keep=%ld nr_unmap_fail=%ld",
+ __entry->nid,
+ __entry->nr_scanned, __entry->nr_reclaimed,
+ __entry->nr_dirty, __entry->nr_writeback,
+ __entry->nr_congested, __entry->nr_immediate,
+ __entry->nr_activate0, __entry->nr_activate1,
+ __entry->nr_ref_keep, __entry->nr_unmap_fail)
+);
+
TRACE_EVENT(mm_vmscan_lru_shrink_inactive,
TP_PROTO(int nid,
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 749cdc110c74..0c2c36bf4c5a 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2126,9 +2126,10 @@ static void shrink_active_list(unsigned long nr_to_scan,
}
static unsigned int reclaim_folio_list(struct list_head *folio_list,
+ unsigned int nr_scanned,
struct pglist_data *pgdat)
{
- struct reclaim_stat dummy_stat;
+ struct reclaim_stat stat;
unsigned int nr_reclaimed;
struct folio *folio;
struct scan_control sc = {
@@ -2139,12 +2140,13 @@ static unsigned int reclaim_folio_list(struct list_head *folio_list,
.no_demotion = 1,
};
- nr_reclaimed = shrink_folio_list(folio_list, pgdat, &sc, &dummy_stat, true);
+ nr_reclaimed = shrink_folio_list(folio_list, pgdat, &sc, &stat, true);
while (!list_empty(folio_list)) {
folio = lru_to_folio(folio_list);
list_del(&folio->lru);
folio_putback_lru(folio);
}
+ trace_mm_vmscan_reclaim_pages(pgdat->node_id, nr_scanned, nr_reclaimed, &stat);
return nr_reclaimed;
}
@@ -2152,6 +2154,7 @@ static unsigned int reclaim_folio_list(struct list_head *folio_list,
unsigned long reclaim_pages(struct list_head *folio_list)
{
int nid;
+ unsigned int nr_scanned = 0;
unsigned int nr_reclaimed = 0;
LIST_HEAD(node_folio_list);
unsigned int noreclaim_flag;
@@ -2168,15 +2171,18 @@ unsigned long reclaim_pages(struct list_head *folio_list)
if (nid == folio_nid(folio)) {
folio_clear_active(folio);
list_move(&folio->lru, &node_folio_list);
+ nr_scanned += folio_nr_pages(folio);
continue;
}
- nr_reclaimed += reclaim_folio_list(&node_folio_list, NODE_DATA(nid));
+ nr_reclaimed += reclaim_folio_list(&node_folio_list, nr_scanned,
+ NODE_DATA(nid));
+ nr_scanned = 0;
nid = folio_nid(lru_to_folio(folio_list));
} while (!list_empty(folio_list));
- nr_reclaimed += reclaim_folio_list(&node_folio_list, NODE_DATA(nid));
-
+ nr_reclaimed += reclaim_folio_list(&node_folio_list, nr_scanned,
+ NODE_DATA(nid));
memalloc_noreclaim_restore(noreclaim_flag);
return nr_reclaimed;
--
2.25.1
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2024-10-17 9:21 UTC | newest]
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[not found] <CGME20241011124931epcas1p176b2ce6a566f7557468dff1e12677a11@epcms1p6>
2024-10-16 13:24 ` [PATCH v2] vmscan: add a vmscan event for reclaim_pages 김재원
2024-10-17 9:20 ` Vlastimil Babka
[not found] <CGME20241011124931epcas1p176b2ce6a566f7557468dff1e12677a11@epcas1p1.samsung.com>
2024-10-11 12:49 ` Jaewon Kim
2024-10-16 13:03 ` Vlastimil Babka
[not found] ` <CGME20241011124931epcas1p176b2ce6a566f7557468dff1e12677a11@epcms1p3>
2024-10-16 13:22 ` Jaewon Kim
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