Re: [External] Re: [PATCH v3 2/7] mm: memcontrol: convert NR_ANON_THPS account to pages

From: Muchun Song
Date: Tue Dec 15 2020 - 08:39:08 EST

On Tue, Dec 15, 2020 at 9:30 PM Michal Hocko <mhocko@xxxxxxxx> wrote:
>
> On Tue 08-12-20 12:18:42, Muchun Song wrote:
> > The unit of NR_ANON_THPS is HPAGE_PMD_NR. Convert the NR_ANON_THPS
> > account to pages.
>
> This changelog could benefit from some improvements. First of all you
> should be clear about the motivation. I believe the previous feedback
> was also to explicitly mention what effect this has on the pcp
> accounting flushing.

Thank you. Will update.

>
> > Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
> > ---
> > drivers/base/node.c | 3 +--
> > fs/proc/meminfo.c | 2 +-
> > mm/huge_memory.c | 3 ++-
> > mm/memcontrol.c | 20 ++++++--------------
> > mm/page_alloc.c | 2 +-
> > mm/rmap.c | 7 ++++---
> > 6 files changed, 15 insertions(+), 22 deletions(-)
> >
> > diff --git a/drivers/base/node.c b/drivers/base/node.c
> > index 04f71c7bc3f8..ec35cb567940 100644
> > --- a/drivers/base/node.c
> > +++ b/drivers/base/node.c
> > @@ -461,8 +461,7 @@ static ssize_t node_read_meminfo(struct device *dev,
> > nid, K(sunreclaimable)
> > #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> > ,
> > - nid, K(node_page_state(pgdat, NR_ANON_THPS) *
> > - HPAGE_PMD_NR),
> > + nid, K(node_page_state(pgdat, NR_ANON_THPS)),
> > nid, K(node_page_state(pgdat, NR_SHMEM_THPS) *
> > HPAGE_PMD_NR),
> > nid, K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED) *
> > diff --git a/fs/proc/meminfo.c b/fs/proc/meminfo.c
> > index d6fc74619625..a635c8a84ddf 100644
> > --- a/fs/proc/meminfo.c
> > +++ b/fs/proc/meminfo.c
> > @@ -129,7 +129,7 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
> >
> > #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> > show_val_kb(m, "AnonHugePages: ",
> > - global_node_page_state(NR_ANON_THPS) * HPAGE_PMD_NR);
> > + global_node_page_state(NR_ANON_THPS));
> > show_val_kb(m, "ShmemHugePages: ",
> > global_node_page_state(NR_SHMEM_THPS) * HPAGE_PMD_NR);
> > show_val_kb(m, "ShmemPmdMapped: ",
> > diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> > index 10dd3cae5f53..66ec454120de 100644
> > --- a/mm/huge_memory.c
> > +++ b/mm/huge_memory.c
> > @@ -2178,7 +2178,8 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd,
> > lock_page_memcg(page);
> > if (atomic_add_negative(-1, compound_mapcount_ptr(page))) {
> > /* Last compound_mapcount is gone. */
> > - __dec_lruvec_page_state(page, NR_ANON_THPS);
> > + __mod_lruvec_page_state(page, NR_ANON_THPS,
> > + -HPAGE_PMD_NR);
> > if (TestClearPageDoubleMap(page)) {
> > /* No need in mapcount reference anymore */
> > for (i = 0; i < HPAGE_PMD_NR; i++)
> > diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> > index 8818bf64d6fe..b18e25a5cdf3 100644
> > --- a/mm/memcontrol.c
> > +++ b/mm/memcontrol.c
> > @@ -1532,7 +1532,7 @@ static struct memory_stat memory_stats[] = {
> > * on some architectures, the macro of HPAGE_PMD_SIZE is not
> > * constant(e.g. powerpc).
> > */
> > - { "anon_thp", 0, NR_ANON_THPS },
> > + { "anon_thp", PAGE_SIZE, NR_ANON_THPS },
> > { "file_thp", 0, NR_FILE_THPS },
> > { "shmem_thp", 0, NR_SHMEM_THPS },
> > #endif
> > @@ -1565,8 +1565,7 @@ static int __init memory_stats_init(void)
> >
> > for (i = 0; i < ARRAY_SIZE(memory_stats); i++) {
> > #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> > - if (memory_stats[i].idx == NR_ANON_THPS ||
> > - memory_stats[i].idx == NR_FILE_THPS ||
> > + if (memory_stats[i].idx == NR_FILE_THPS ||
> > memory_stats[i].idx == NR_SHMEM_THPS)
> > memory_stats[i].ratio = HPAGE_PMD_SIZE;
> > #endif
> > @@ -4088,10 +4087,6 @@ static int memcg_stat_show(struct seq_file *m, void *v)
> > if (memcg1_stats[i] == MEMCG_SWAP && !do_memsw_account())
> > continue;
> > nr = memcg_page_state_local(memcg, memcg1_stats[i]);
> > -#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> > - if (memcg1_stats[i] == NR_ANON_THPS)
> > - nr *= HPAGE_PMD_NR;
> > -#endif
> > seq_printf(m, "%s %lu\n", memcg1_stat_names[i], nr * PAGE_SIZE);
> > }
> >
> > @@ -4122,10 +4117,6 @@ static int memcg_stat_show(struct seq_file *m, void *v)
> > if (memcg1_stats[i] == MEMCG_SWAP && !do_memsw_account())
> > continue;
> > nr = memcg_page_state(memcg, memcg1_stats[i]);
> > -#ifdef CONFIG_TRANSPARENT_HUGEPAGE
> > - if (memcg1_stats[i] == NR_ANON_THPS)
> > - nr *= HPAGE_PMD_NR;
> > -#endif
> > seq_printf(m, "total_%s %llu\n", memcg1_stat_names[i],
> > (u64)nr * PAGE_SIZE);
> > }
> > @@ -5653,10 +5644,11 @@ static int mem_cgroup_move_account(struct page *page,
> > __mod_lruvec_state(from_vec, NR_ANON_MAPPED, -nr_pages);
> > __mod_lruvec_state(to_vec, NR_ANON_MAPPED, nr_pages);
> > if (PageTransHuge(page)) {
> > - __dec_lruvec_state(from_vec, NR_ANON_THPS);
> > - __inc_lruvec_state(to_vec, NR_ANON_THPS);
> > + __mod_lruvec_state(from_vec, NR_ANON_THPS,
> > + -nr_pages);
> > + __mod_lruvec_state(to_vec, NR_ANON_THPS,
> > + nr_pages);
> > }
> > -
> > }
> > } else {
> > __mod_lruvec_state(from_vec, NR_FILE_PAGES, -nr_pages);
> > diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> > index 469e28f95ce7..1700f52b7869 100644
> > --- a/mm/page_alloc.c
> > +++ b/mm/page_alloc.c
> > @@ -5580,7 +5580,7 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask)
> > K(node_page_state(pgdat, NR_SHMEM_THPS) * HPAGE_PMD_NR),
> > K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED)
> > * HPAGE_PMD_NR),
> > - K(node_page_state(pgdat, NR_ANON_THPS) * HPAGE_PMD_NR),
> > + K(node_page_state(pgdat, NR_ANON_THPS)),
> > #endif
> > K(node_page_state(pgdat, NR_WRITEBACK_TEMP)),
> > node_page_state(pgdat, NR_KERNEL_STACK_KB),
> > diff --git a/mm/rmap.c b/mm/rmap.c
> > index 08c56aaf72eb..f59e92e26b61 100644
> > --- a/mm/rmap.c
> > +++ b/mm/rmap.c
> > @@ -1144,7 +1144,8 @@ void do_page_add_anon_rmap(struct page *page,
> > * disabled.
> > */
> > if (compound)
> > - __inc_lruvec_page_state(page, NR_ANON_THPS);
> > + __mod_lruvec_page_state(page, NR_ANON_THPS,
> > + HPAGE_PMD_NR);
> > __mod_lruvec_page_state(page, NR_ANON_MAPPED, nr);
> > }
> >
> > @@ -1186,7 +1187,7 @@ void page_add_new_anon_rmap(struct page *page,
> > if (hpage_pincount_available(page))
> > atomic_set(compound_pincount_ptr(page), 0);
> >
> > - __inc_lruvec_page_state(page, NR_ANON_THPS);
> > + __mod_lruvec_page_state(page, NR_ANON_THPS, HPAGE_PMD_NR);
> > } else {
> > /* Anon THP always mapped first with PMD */
> > VM_BUG_ON_PAGE(PageTransCompound(page), page);
> > @@ -1292,7 +1293,7 @@ static void page_remove_anon_compound_rmap(struct page *page)
> > if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE))
> > return;
> >
> > - __dec_lruvec_page_state(page, NR_ANON_THPS);
> > + __mod_lruvec_page_state(page, NR_ANON_THPS, -HPAGE_PMD_NR);
> >
> > if (TestClearPageDoubleMap(page)) {
> > /*
> > --
> > 2.11.0
>
> --
> Michal Hocko
> SUSE Labs



--
Yours,
Muchun