Hey Yang, Thanks for taking time to review! On Thu, Apr 25, 2024 at 3:44 AM Yang Shi <shy828301@xxxxxxxxx> wrote: > > On Wed, Apr 24, 2024 at 6:53 AM Lance Yang <ioworker0@xxxxxxxxx> wrote: > > > > At present, the split counters in THP statistics no longer include > > PTE-mapped mTHP. Therefore, this commit introduces per-order mTHP split > > counters to monitor the frequency of mTHP splits. This will assist > > developers in better analyzing and optimizing system performance. > > > > /sys/kernel/mm/transparent_hugepage/hugepages-<size>/stats > > split_page > > split_page_failed > > deferred_split_page > > The deferred_split_page counter may easily go insane with the fix from > https://lore.kernel.org/linux-mm/20240411153232.169560-1-zi.yan@xxxxxxxx/ > > Zi Yan, > > Will you submit v2 for this patch soon? Thanks for bringing this to my attention! I'll follow Zi Yan's patch, then submit the next version. Thanks, Lance > > > > > > Signed-off-by: Lance Yang <ioworker0@xxxxxxxxx> > > --- > > include/linux/huge_mm.h | 3 +++ > > mm/huge_memory.c | 14 ++++++++++++-- > > 2 files changed, 15 insertions(+), 2 deletions(-) > > > > diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h > > index 56c7ea73090b..7b9c6590e1f7 100644 > > --- a/include/linux/huge_mm.h > > +++ b/include/linux/huge_mm.h > > @@ -272,6 +272,9 @@ enum mthp_stat_item { > > MTHP_STAT_ANON_FAULT_FALLBACK_CHARGE, > > MTHP_STAT_ANON_SWPOUT, > > MTHP_STAT_ANON_SWPOUT_FALLBACK, > > + MTHP_STAT_SPLIT_PAGE, > > + MTHP_STAT_SPLIT_PAGE_FAILED, > > + MTHP_STAT_DEFERRED_SPLIT_PAGE, > > __MTHP_STAT_COUNT > > }; > > > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > > index 055df5aac7c3..52db888e47a6 100644 > > --- a/mm/huge_memory.c > > +++ b/mm/huge_memory.c > > @@ -557,6 +557,9 @@ DEFINE_MTHP_STAT_ATTR(anon_fault_fallback, MTHP_STAT_ANON_FAULT_FALLBACK); > > DEFINE_MTHP_STAT_ATTR(anon_fault_fallback_charge, MTHP_STAT_ANON_FAULT_FALLBACK_CHARGE); > > DEFINE_MTHP_STAT_ATTR(anon_swpout, MTHP_STAT_ANON_SWPOUT); > > DEFINE_MTHP_STAT_ATTR(anon_swpout_fallback, MTHP_STAT_ANON_SWPOUT_FALLBACK); > > +DEFINE_MTHP_STAT_ATTR(split_page, MTHP_STAT_SPLIT_PAGE); > > +DEFINE_MTHP_STAT_ATTR(split_page_failed, MTHP_STAT_SPLIT_PAGE_FAILED); > > +DEFINE_MTHP_STAT_ATTR(deferred_split_page, MTHP_STAT_DEFERRED_SPLIT_PAGE); > > > > static struct attribute *stats_attrs[] = { > > &anon_fault_alloc_attr.attr, > > @@ -564,6 +567,9 @@ static struct attribute *stats_attrs[] = { > > &anon_fault_fallback_charge_attr.attr, > > &anon_swpout_attr.attr, > > &anon_swpout_fallback_attr.attr, > > + &split_page_attr.attr, > > + &split_page_failed_attr.attr, > > + &deferred_split_page_attr.attr, > > NULL, > > }; > > > > @@ -3083,7 +3089,7 @@ int split_huge_page_to_list_to_order(struct page *page, struct list_head *list, > > XA_STATE_ORDER(xas, &folio->mapping->i_pages, folio->index, new_order); > > struct anon_vma *anon_vma = NULL; > > struct address_space *mapping = NULL; > > - bool is_thp = folio_test_pmd_mappable(folio); > > + int order = folio_order(folio); > > int extra_pins, ret; > > pgoff_t end; > > bool is_hzp; > > @@ -3262,8 +3268,10 @@ int split_huge_page_to_list_to_order(struct page *page, struct list_head *list, > > i_mmap_unlock_read(mapping); > > out: > > xas_destroy(&xas); > > - if (is_thp) > > + if (order >= HPAGE_PMD_ORDER) > > count_vm_event(!ret ? THP_SPLIT_PAGE : THP_SPLIT_PAGE_FAILED); > > + count_mthp_stat(order, !ret ? MTHP_STAT_SPLIT_PAGE : > > + MTHP_STAT_SPLIT_PAGE_FAILED); > > return ret; > > } > > > > @@ -3327,6 +3335,8 @@ void deferred_split_folio(struct folio *folio) > > if (list_empty(&folio->_deferred_list)) { > > if (folio_test_pmd_mappable(folio)) > > count_vm_event(THP_DEFERRED_SPLIT_PAGE); > > + count_mthp_stat(folio_order(folio), > > + MTHP_STAT_DEFERRED_SPLIT_PAGE); > > list_add_tail(&folio->_deferred_list, &ds_queue->split_queue); > > ds_queue->split_queue_len++; > > #ifdef CONFIG_MEMCG > > -- > > 2.33.1 > > > >
