diff --git a/Documentation/admin-guide/mm/transhuge.rst b/Documentation/admin-guide/mm/transhuge.rst index e7232b46fe14..1f72b00af5d3 100644 --- a/Documentation/admin-guide/mm/transhuge.rst +++ b/Documentation/admin-guide/mm/transhuge.rst @@ -501,6 +501,19 @@ swpout_fallback Usually because failed to allocate some continuous swap space for the huge page. +file_alloc + is incremented every time a file huge page is successfully + allocated. + +file_fallback + is incremented if a file huge page is attempted to be allocated + but fails and instead falls back to using small pages. + +file_fallback_charge + is incremented if a file huge page cannot be charged and instead + falls back to using small pages even though the allocation was + successful. + As the system ages, allocating huge pages may be expensive as the system uses memory compaction to copy data around memory to free a huge page for use. There are some counters in ``/proc/vmstat`` to help diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index 53b7a137f460..7ad41de5eaea 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -281,6 +281,9 @@ enum mthp_stat_item { MTHP_STAT_ANON_FAULT_FALLBACK_CHARGE, MTHP_STAT_SWPOUT, MTHP_STAT_SWPOUT_FALLBACK, + MTHP_STAT_FILE_ALLOC, + MTHP_STAT_FILE_FALLBACK, + MTHP_STAT_FILE_FALLBACK_CHARGE, __MTHP_STAT_COUNT }; diff --git a/mm/huge_memory.c b/mm/huge_memory.c index af6f239b0f97..f55362a73e2d 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -556,6 +556,9 @@ 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(swpout, MTHP_STAT_SWPOUT); DEFINE_MTHP_STAT_ATTR(swpout_fallback, MTHP_STAT_SWPOUT_FALLBACK); +DEFINE_MTHP_STAT_ATTR(file_alloc, MTHP_STAT_FILE_ALLOC); +DEFINE_MTHP_STAT_ATTR(file_fallback, MTHP_STAT_FILE_FALLBACK); +DEFINE_MTHP_STAT_ATTR(file_fallback_charge, MTHP_STAT_FILE_FALLBACK_CHARGE); static struct attribute *stats_attrs[] = { &anon_fault_alloc_attr.attr, @@ -563,6 +566,9 @@ static struct attribute *stats_attrs[] = { &anon_fault_fallback_charge_attr.attr, &swpout_attr.attr, &swpout_fallback_attr.attr, + &file_alloc_attr.attr, + &file_fallback_attr.attr, + &file_fallback_charge_attr.attr, NULL, }; diff --git a/mm/shmem.c b/mm/shmem.c index 224162aa204b..d09c6bf1f28a 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1772,6 +1772,9 @@ static struct folio *shmem_alloc_and_add_folio(struct vm_fault *vmf, if (pages == HPAGE_PMD_NR) count_vm_event(THP_FILE_FALLBACK); +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + count_mthp_stat(order, MTHP_STAT_FILE_FALLBACK); +#endif order = next_order(&suitable_orders, order); } } else { @@ -1791,9 +1794,15 @@ allocated: if (xa_find(&mapping->i_pages, &index, index + pages - 1, XA_PRESENT)) { error = -EEXIST; - } else if (pages == HPAGE_PMD_NR) { - count_vm_event(THP_FILE_FALLBACK); - count_vm_event(THP_FILE_FALLBACK_CHARGE); + } else if (pages > 1) { + if (pages == HPAGE_PMD_NR) { + count_vm_event(THP_FILE_FALLBACK); + count_vm_event(THP_FILE_FALLBACK_CHARGE); + } +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + count_mthp_stat(folio_order(folio), MTHP_STAT_FILE_FALLBACK); + count_mthp_stat(folio_order(folio), MTHP_STAT_FILE_FALLBACK_CHARGE); +#endif } goto unlock; } @@ -2167,6 +2176,9 @@ repeat: if (!IS_ERR(folio)) { if (folio_test_pmd_mappable(folio)) count_vm_event(THP_FILE_ALLOC); +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + count_mthp_stat(folio_order(folio), MTHP_STAT_FILE_ALLOC); +#endif goto alloced; } if (PTR_ERR(folio) == -EEXIST)