The patch titled
Subject: mm: multi-gen LRU: add helpers in page table walks
has been added to the -mm mm-unstable branch. Its filename is
mm-multi-gen-lru-add-helpers-in-page-table-walks.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-multi-gen-lru-add-helpers-in-page-table-walks.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: "T.J. Alumbaugh" <talumbau@xxxxxxxxxx>
Subject: mm: multi-gen LRU: add helpers in page table walks
Date: Mon, 22 May 2023 11:20:57 +0000
Add helpers to page table walking code:
- Clarifies intent via name "should_walk_mmu" and "should_clear_pmd_young"
- Avoids repeating same logic in two places
Link: https://lkml.kernel.org/r/20230522112058.2965866-3-talumbau@xxxxxxxxxx
Signed-off-by: T.J. Alumbaugh <talumbau@xxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Yuanchu Xie <yuanchu@xxxxxxxxxx>
Cc: Yu Zhao <yuzhao@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/vmscan.c | 20 +++++++++++++++-----
1 file changed, 15 insertions(+), 5 deletions(-)
--- a/mm/vmscan.c~mm-multi-gen-lru-add-helpers-in-page-table-walks
+++ a/mm/vmscan.c
@@ -3234,6 +3234,16 @@ DEFINE_STATIC_KEY_ARRAY_FALSE(lru_gen_ca
#define get_cap(cap) static_branch_unlikely(&lru_gen_caps[cap])
#endif
+static bool should_walk_mmu(void)
+{
+ return arch_has_hw_pte_young() && get_cap(LRU_GEN_MM_WALK);
+}
+
+static bool should_clear_pmd_young(void)
+{
+ return arch_has_hw_nonleaf_pmd_young() && get_cap(LRU_GEN_NONLEAF_YOUNG);
+}
+
/******************************************************************************
* shorthand helpers
******************************************************************************/
@@ -4098,7 +4108,7 @@ static void walk_pmd_range_locked(pud_t
goto next;
if (!pmd_trans_huge(pmd[i])) {
- if (arch_has_hw_nonleaf_pmd_young() && get_cap(LRU_GEN_NONLEAF_YOUNG))
+ if (should_clear_pmd_young())
pmdp_test_and_clear_young(vma, addr, pmd + i);
goto next;
}
@@ -4191,7 +4201,7 @@ restart:
#endif
walk->mm_stats[MM_NONLEAF_TOTAL]++;
- if (arch_has_hw_nonleaf_pmd_young() && get_cap(LRU_GEN_NONLEAF_YOUNG)) {
+ if (should_clear_pmd_young()) {
if (!pmd_young(val))
continue;
@@ -4493,7 +4503,7 @@ static bool try_to_inc_max_seq(struct lr
* handful of PTEs. Spreading the work out over a period of time usually
* is less efficient, but it avoids bursty page faults.
*/
- if (!arch_has_hw_pte_young() || !get_cap(LRU_GEN_MM_WALK)) {
+ if (!should_walk_mmu()) {
success = iterate_mm_list_nowalk(lruvec, max_seq);
goto done;
}
@@ -5730,10 +5740,10 @@ static ssize_t enabled_show(struct kobje
if (get_cap(LRU_GEN_CORE))
caps |= BIT(LRU_GEN_CORE);
- if (arch_has_hw_pte_young() && get_cap(LRU_GEN_MM_WALK))
+ if (should_walk_mmu())
caps |= BIT(LRU_GEN_MM_WALK);
- if (arch_has_hw_nonleaf_pmd_young() && get_cap(LRU_GEN_NONLEAF_YOUNG))
+ if (should_clear_pmd_young())
caps |= BIT(LRU_GEN_NONLEAF_YOUNG);
return sysfs_emit(buf, "0x%04x\n", caps);
_
Patches currently in -mm which might be from talumbau@xxxxxxxxxx are
mm-multi-gen-lru-use-macro-for-bitmap.patch
mm-multi-gen-lru-cleanup-lru_gen_soft_reclaim.patch
mm-multi-gen-lru-add-helpers-in-page-table-walks.patch
mm-multi-gen-lru-cleanup-lru_gen_test_recent.patch
