The patch titled
Subject: mm/vmstat: add events for THP max_ptes_* exceeds
has been removed from the -mm tree. Its filename was
mm-vmstat-add-events-for-thp-max_ptes_-exceeds.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
From: Yang Yang <yang.yang29@xxxxxxxxxx>
Subject: mm/vmstat: add events for THP max_ptes_* exceeds
There are interfaces to adjust max_ptes_none, max_ptes_swap,
max_ptes_shared values, see
/sys/kernel/mm/transparent_hugepage/khugepaged/.
But system administrator maynot know which value is the best. So Add
those events to support adjusting max_ptes_* to suitable values.
For example, if default max_ptes_swap value causes too much failures, and
system uses zram whose IO is fast, administrator could increase
max_ptes_swap until THP_SCAN_EXCEED_SWAP_PTE not increase anymore.
Link: https://lkml.kernel.org/r/20211225094036.574157-1-yang.yang29@xxxxxxxxxx
Signed-off-by: Yang Yang <yang.yang29@xxxxxxxxxx>
Cc: "Huang, Ying" <ying.huang@xxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Saravanan D <saravanand@xxxxxx>
Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/vm_event_item.h | 3 +++
mm/khugepaged.c | 7 +++++++
mm/vmstat.c | 3 +++
3 files changed, 13 insertions(+)
--- a/include/linux/vm_event_item.h~mm-vmstat-add-events-for-thp-max_ptes_-exceeds
+++ a/include/linux/vm_event_item.h
@@ -98,6 +98,9 @@ enum vm_event_item { PGPGIN, PGPGOUT, PS
THP_SPLIT_PAGE_FAILED,
THP_DEFERRED_SPLIT_PAGE,
THP_SPLIT_PMD,
+ THP_SCAN_EXCEED_NONE_PTE,
+ THP_SCAN_EXCEED_SWAP_PTE,
+ THP_SCAN_EXCEED_SHARED_PTE,
#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
THP_SPLIT_PUD,
#endif
--- a/mm/khugepaged.c~mm-vmstat-add-events-for-thp-max_ptes_-exceeds
+++ a/mm/khugepaged.c
@@ -618,6 +618,7 @@ static int __collapse_huge_page_isolate(
continue;
} else {
result = SCAN_EXCEED_NONE_PTE;
+ count_vm_event(THP_SCAN_EXCEED_NONE_PTE);
goto out;
}
}
@@ -636,6 +637,7 @@ static int __collapse_huge_page_isolate(
if (page_mapcount(page) > 1 &&
++shared > khugepaged_max_ptes_shared) {
result = SCAN_EXCEED_SHARED_PTE;
+ count_vm_event(THP_SCAN_EXCEED_SHARED_PTE);
goto out;
}
@@ -1253,6 +1255,7 @@ static int khugepaged_scan_pmd(struct mm
continue;
} else {
result = SCAN_EXCEED_SWAP_PTE;
+ count_vm_event(THP_SCAN_EXCEED_SWAP_PTE);
goto out_unmap;
}
}
@@ -1262,6 +1265,7 @@ static int khugepaged_scan_pmd(struct mm
continue;
} else {
result = SCAN_EXCEED_NONE_PTE;
+ count_vm_event(THP_SCAN_EXCEED_NONE_PTE);
goto out_unmap;
}
}
@@ -1290,6 +1294,7 @@ static int khugepaged_scan_pmd(struct mm
if (page_mapcount(page) > 1 &&
++shared > khugepaged_max_ptes_shared) {
result = SCAN_EXCEED_SHARED_PTE;
+ count_vm_event(THP_SCAN_EXCEED_SHARED_PTE);
goto out_unmap;
}
@@ -2000,6 +2005,7 @@ static void khugepaged_scan_file(struct
if (xa_is_value(page)) {
if (++swap > khugepaged_max_ptes_swap) {
result = SCAN_EXCEED_SWAP_PTE;
+ count_vm_event(THP_SCAN_EXCEED_SWAP_PTE);
break;
}
continue;
@@ -2046,6 +2052,7 @@ static void khugepaged_scan_file(struct
if (result == SCAN_SUCCEED) {
if (present < HPAGE_PMD_NR - khugepaged_max_ptes_none) {
result = SCAN_EXCEED_NONE_PTE;
+ count_vm_event(THP_SCAN_EXCEED_NONE_PTE);
} else {
node = khugepaged_find_target_node();
collapse_file(mm, file, start, hpage, node);
--- a/mm/vmstat.c~mm-vmstat-add-events-for-thp-max_ptes_-exceeds
+++ a/mm/vmstat.c
@@ -1353,6 +1353,9 @@ const char * const vmstat_text[] = {
"thp_split_page_failed",
"thp_deferred_split_page",
"thp_split_pmd",
+ "thp_scan_exceed_none_pte",
+ "thp_scan_exceed_swap_pte",
+ "thp_scan_exceed_share_pte",
#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
"thp_split_pud",
#endif
_
Patches currently in -mm which might be from yang.yang29@xxxxxxxxxx are
