* [PATCH v3 0/2] promote mapped executable folios after first usage for MGLRU @ 2026-07-17 10:05 Baolin Wang 2026-07-17 10:05 ` [PATCH v3 1/2] mm: vmscan: convert folio_referenced() to use vma_flags_t Baolin Wang 2026-07-17 10:05 ` [PATCH v3 2/2] mm: mglru: promote mapped executable folios after first usage Baolin Wang 0 siblings, 2 replies; 6+ messages in thread From: Baolin Wang @ 2026-07-17 10:05 UTC (permalink / raw) To: akpm, david, ljs, hannes Cc: riel, liam, vbabka, harry, jannh, lance.yang, kasong, qi.zheng, shakeel.butt, baohua, axelrasmussen, yuanchu, weixugc, mhocko, baolin.wang, linux-mm, linux-kernel Now MGLRU's protection of mapped executable file folios is less reliable. Follow the classical LRU's logic, promoting mapped executable file folios after their first usage to give executable code a better chance to stay in memory and improve workload performance (See patch 2 for more details). Changes from v2: https://lore.kernel.org/all/cover.1784197559.git.baolin.wang@linux.alibaba.com/ - Add acked tag from David. Thanks. - Rename the exec-file-folio helper and move it into vmscan.c (per David). Changes from v1: https://lore.kernel.org/all/4b921ed528c483e13c9e22d1ae44ba58b4a15b0b.1784096432.git.baolin.wang@linux.alibaba.com/ - Add a new patch to clean up vma flags as preparation. - Add a new helper to check exec file folios (per Kaisui). - Promote exec file folios in lru_gen_set_refs (Per Sashiko). Baolin Wang (2): mm: vmscan: convert folio_referenced() to use vma_flags_t mm: mglru: promote mapped executable folios after first usage include/linux/rmap.h | 7 +++--- mm/rmap.c | 19 ++++++++------- mm/vmscan.c | 57 ++++++++++++++++++++++++++++---------------- 3 files changed, 50 insertions(+), 33 deletions(-) -- 2.47.3 ^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v3 1/2] mm: vmscan: convert folio_referenced() to use vma_flags_t 2026-07-17 10:05 [PATCH v3 0/2] promote mapped executable folios after first usage for MGLRU Baolin Wang @ 2026-07-17 10:05 ` Baolin Wang 2026-07-17 12:34 ` Johannes Weiner 2026-07-17 10:05 ` [PATCH v3 2/2] mm: mglru: promote mapped executable folios after first usage Baolin Wang 1 sibling, 1 reply; 6+ messages in thread From: Baolin Wang @ 2026-07-17 10:05 UTC (permalink / raw) To: akpm, david, ljs, hannes Cc: riel, liam, vbabka, harry, jannh, lance.yang, kasong, qi.zheng, shakeel.butt, baohua, axelrasmussen, yuanchu, weixugc, mhocko, baolin.wang, linux-mm, linux-kernel Replace use of the legacy vm_flags_t flags with vma_flags_t values for folio_referenced() and related logic. This is also a preparation for the following changes. No functional changes. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Acked-by: David Hildenbrand (Arm) <david@kernel.org> --- include/linux/rmap.h | 7 +++---- mm/rmap.c | 19 +++++++++++-------- mm/vmscan.c | 14 +++++++------- 3 files changed, 21 insertions(+), 19 deletions(-) diff --git a/include/linux/rmap.h b/include/linux/rmap.h index 8dc0871e5f00..e090aa09825d 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -843,7 +843,7 @@ static inline int folio_try_share_anon_rmap_pmd(struct folio *folio, * Called from mm/vmscan.c to handle paging out */ int folio_referenced(struct folio *, int is_locked, - struct mem_cgroup *memcg, vm_flags_t *vm_flags); + struct mem_cgroup *memcg, vma_flags_t *vma_flags); void try_to_migrate(struct folio *folio, enum ttu_flags flags); void try_to_unmap(struct folio *, enum ttu_flags flags); @@ -975,10 +975,9 @@ struct anon_vma *folio_lock_anon_vma_read(const struct folio *folio, #define anon_vma_prepare(vma) (0) static inline int folio_referenced(struct folio *folio, int is_locked, - struct mem_cgroup *memcg, - vm_flags_t *vm_flags) + struct mem_cgroup *memcg, vma_flags_t *vma_flags) { - *vm_flags = 0; + vma_flags_clear_all(vma_flags); return 0; } diff --git a/mm/rmap.c b/mm/rmap.c index e854679553b9..4085540b6a25 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -907,7 +907,7 @@ pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address) struct folio_referenced_arg { int mapcount; int referenced; - vm_flags_t vm_flags; + vma_flags_t vma_flags; struct mem_cgroup *memcg; }; @@ -926,7 +926,7 @@ static bool folio_referenced_one(struct folio *folio, address = pvmw.address; nr = 1; - if (vma->vm_flags & VM_LOCKED) { + if (vma_test(vma, VMA_LOCKED_BIT)) { ptes++; pra->mapcount--; @@ -947,7 +947,7 @@ static bool folio_referenced_one(struct folio *folio, /* Restore the mlock which got missed */ mlock_vma_folio(folio, vma); page_vma_mapped_walk_done(&pvmw); - pra->vm_flags |= VM_LOCKED; + vma_flags_set(&pra->vma_flags, VMA_LOCKED_BIT); return false; /* To break the loop */ } @@ -1015,8 +1015,11 @@ static bool folio_referenced_one(struct folio *folio, referenced++; if (referenced) { + vma_flags_t vma_flags = vma->flags; + pra->referenced++; - pra->vm_flags |= vma->vm_flags & ~VM_LOCKED; + vma_flags_clear(&vma_flags, VMA_LOCKED_BIT); + vma_flags_set_mask(&pra->vma_flags, vma_flags); } if (!pra->mapcount) @@ -1054,7 +1057,7 @@ static bool invalid_folio_referenced_vma(struct vm_area_struct *vma, void *arg) * @folio: The folio to test. * @is_locked: Caller holds lock on the folio. * @memcg: target memory cgroup - * @vm_flags: A combination of all the vma->vm_flags which referenced the folio. + * @vma_flags: A combination of all the vma->flags which referenced the folio. * * Quick test_and_clear_referenced for all mappings of a folio, * @@ -1062,7 +1065,7 @@ static bool invalid_folio_referenced_vma(struct vm_area_struct *vma, void *arg) * the function bailed out due to rmap lock contention. */ int folio_referenced(struct folio *folio, int is_locked, - struct mem_cgroup *memcg, vm_flags_t *vm_flags) + struct mem_cgroup *memcg, vma_flags_t *vma_flags) { bool we_locked = false; struct folio_referenced_arg pra = { @@ -1078,7 +1081,7 @@ int folio_referenced(struct folio *folio, int is_locked, }; VM_WARN_ON_ONCE_FOLIO(folio_is_zone_device(folio), folio); - *vm_flags = 0; + vma_flags_clear_all(vma_flags); if (!pra.mapcount) return 0; @@ -1092,7 +1095,7 @@ int folio_referenced(struct folio *folio, int is_locked, } rmap_walk(folio, &rwc); - *vm_flags = pra.vm_flags; + vma_flags_set_mask(vma_flags, pra.vma_flags); if (we_locked) folio_unlock(folio); diff --git a/mm/vmscan.c b/mm/vmscan.c index 986dde8e7429..de62899c108d 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -861,16 +861,16 @@ static enum folio_references folio_check_references(struct folio *folio, struct scan_control *sc) { int referenced_ptes, referenced_folio; - vm_flags_t vm_flags; + vma_flags_t vma_flags; referenced_ptes = folio_referenced(folio, 1, sc->target_mem_cgroup, - &vm_flags); + &vma_flags); /* * The supposedly reclaimable folio was found to be in a VM_LOCKED vma. * Let the folio, now marked Mlocked, be moved to the unevictable list. */ - if (vm_flags & VM_LOCKED) + if (vma_flags_test(&vma_flags, VMA_LOCKED_BIT)) return FOLIOREF_ACTIVATE; /* @@ -914,7 +914,7 @@ static enum folio_references folio_check_references(struct folio *folio, /* * Activate file-backed executable folios after first usage. */ - if ((vm_flags & VM_EXEC) && folio_is_file_lru(folio)) + if (vma_flags_test(&vma_flags, VMA_EXEC_BIT) && folio_is_file_lru(folio)) return FOLIOREF_ACTIVATE; return FOLIOREF_KEEP; @@ -2065,7 +2065,7 @@ static void shrink_active_list(unsigned long nr_to_scan, { unsigned long nr_taken; unsigned long nr_scanned; - vm_flags_t vm_flags; + vma_flags_t vma_flags; LIST_HEAD(l_hold); /* The folios which were snipped off */ LIST_HEAD(l_active); LIST_HEAD(l_inactive); @@ -2109,7 +2109,7 @@ static void shrink_active_list(unsigned long nr_to_scan, /* Referenced or rmap lock contention: rotate */ if (folio_referenced(folio, 0, sc->target_mem_cgroup, - &vm_flags) != 0) { + &vma_flags) != 0) { /* * Identify referenced, file-backed active folios and * give them one more trip around the active list. So @@ -2119,7 +2119,7 @@ static void shrink_active_list(unsigned long nr_to_scan, * IO, plus JVM can create lots of anon VM_EXEC folios, * so we ignore them here. */ - if ((vm_flags & VM_EXEC) && folio_is_file_lru(folio)) { + if (vma_flags_test(&vma_flags, VMA_EXEC_BIT) && folio_is_file_lru(folio)) { nr_rotated += folio_nr_pages(folio); list_add(&folio->lru, &l_active); continue; -- 2.47.3 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v3 1/2] mm: vmscan: convert folio_referenced() to use vma_flags_t 2026-07-17 10:05 ` [PATCH v3 1/2] mm: vmscan: convert folio_referenced() to use vma_flags_t Baolin Wang @ 2026-07-17 12:34 ` Johannes Weiner 0 siblings, 0 replies; 6+ messages in thread From: Johannes Weiner @ 2026-07-17 12:34 UTC (permalink / raw) To: Baolin Wang Cc: akpm, david, ljs, riel, liam, vbabka, harry, jannh, lance.yang, kasong, qi.zheng, shakeel.butt, baohua, axelrasmussen, yuanchu, weixugc, mhocko, linux-mm, linux-kernel On Fri, Jul 17, 2026 at 06:05:33PM +0800, Baolin Wang wrote: > Replace use of the legacy vm_flags_t flags with vma_flags_t values for > folio_referenced() and related logic. This is also a preparation for the > following changes. > > No functional changes. > > Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> > Acked-by: David Hildenbrand (Arm) <david@kernel.org> Had to double take on the ors and ands and nots conversions, but looks correct to me. Acked-by: Johannes Weiner <hannes@cmpxchg.org> ^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v3 2/2] mm: mglru: promote mapped executable folios after first usage 2026-07-17 10:05 [PATCH v3 0/2] promote mapped executable folios after first usage for MGLRU Baolin Wang 2026-07-17 10:05 ` [PATCH v3 1/2] mm: vmscan: convert folio_referenced() to use vma_flags_t Baolin Wang @ 2026-07-17 10:05 ` Baolin Wang 2026-07-17 12:44 ` Johannes Weiner 1 sibling, 1 reply; 6+ messages in thread From: Baolin Wang @ 2026-07-17 10:05 UTC (permalink / raw) To: akpm, david, ljs, hannes Cc: riel, liam, vbabka, harry, jannh, lance.yang, kasong, qi.zheng, shakeel.butt, baohua, axelrasmussen, yuanchu, weixugc, mhocko, baolin.wang, linux-mm, linux-kernel Classical LRU protects mapped executable file folios through commit 8cab4754d24a0 ("vmscan: make mapped executable pages the first class citizen") and commit c909e99364c8 ("vmscan: activate executable pages after first usage"), giving executable code a better chance to stay in memory, avoiding IO thrashing and improving workload performance. However, MGLRU's protection of mapped executable file folios is less reliable. Although shrink_folio_list() checks references, the access flag of mapped executable file folios may have already been checked and cleared by lru_gen_look_around() or walk_mm(). Additionally, folio_update_gen() or lru_gen_set_refs() only sets the 'PG_referenced' flag for mapped executable file folios, which causes shrink_folio_list() to ignore the first usage of these mapped executable file folios and reclaim them easily. Follow the classical LRU's logic, promoting mapped executable file folios after their first usage in folio_update_gen() and lru_gen_set_refs(), giving executable code a better chance to stay in memory. On my 32-core Arm machine, with the memcg limit set to 2G, running 'make -j32' to build kernel showed some improvement in sys time. base patched 9248.543s 7861.579s While we are at it, introduce a new helper to check mapped executable file folios. Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> --- mm/vmscan.c | 47 +++++++++++++++++++++++++++++++---------------- 1 file changed, 31 insertions(+), 16 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index de62899c108d..1040bf9f96e8 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -268,6 +268,12 @@ static int sc_swappiness(struct scan_control *sc, struct mem_cgroup *memcg) } #endif +static inline bool is_exec_file_folio(const struct folio *folio, + const vma_flags_t *vma_flags) +{ + return vma_flags_test(vma_flags, VMA_EXEC_BIT) && folio_is_file_lru(folio); +} + static void set_task_reclaim_state(struct task_struct *task, struct reclaim_state *rs) { @@ -835,11 +841,15 @@ enum folio_references { * with PG_active set. In contrast, the aging (page table walk) path uses * folio_update_gen(). */ -static bool lru_gen_set_refs(struct folio *folio) +static bool lru_gen_set_refs(struct folio *folio, const vma_flags_t *vma_flags) { /* see the comment on LRU_REFS_FLAGS */ if (!folio_test_referenced(folio) && !folio_test_workingset(folio)) { set_mask_bits(&folio->flags.f, LRU_REFS_MASK, BIT(PG_referenced)); + /* Activate file-backed executable folios after first usage. */ + if (is_exec_file_folio(folio, vma_flags)) + return true; + return false; } @@ -851,7 +861,7 @@ static bool lru_gen_set_refs(struct folio *folio) return true; } #else -static bool lru_gen_set_refs(struct folio *folio) +static bool lru_gen_set_refs(struct folio *folio, const vma_flags_t *vma_flags) { return false; } @@ -886,7 +896,7 @@ static enum folio_references folio_check_references(struct folio *folio, if (!referenced_ptes) return FOLIOREF_RECLAIM; - return lru_gen_set_refs(folio) ? FOLIOREF_ACTIVATE : FOLIOREF_KEEP; + return lru_gen_set_refs(folio, &vma_flags) ? FOLIOREF_ACTIVATE : FOLIOREF_KEEP; } referenced_folio = folio_test_clear_referenced(folio); @@ -914,7 +924,7 @@ static enum folio_references folio_check_references(struct folio *folio, /* * Activate file-backed executable folios after first usage. */ - if (vma_flags_test(&vma_flags, VMA_EXEC_BIT) && folio_is_file_lru(folio)) + if (is_exec_file_folio(folio, &vma_flags)) return FOLIOREF_ACTIVATE; return FOLIOREF_KEEP; @@ -2119,7 +2129,7 @@ static void shrink_active_list(unsigned long nr_to_scan, * IO, plus JVM can create lots of anon VM_EXEC folios, * so we ignore them here. */ - if (vma_flags_test(&vma_flags, VMA_EXEC_BIT) && folio_is_file_lru(folio)) { + if (is_exec_file_folio(folio, &vma_flags)) { nr_rotated += folio_nr_pages(folio); list_add(&folio->lru, &l_active); continue; @@ -3188,7 +3198,7 @@ static bool positive_ctrl_err(struct ctrl_pos *sp, struct ctrl_pos *pv) ******************************************************************************/ /* promote pages accessed through page tables */ -static int folio_update_gen(struct folio *folio, int gen) +static int folio_update_gen(struct folio *folio, int gen, const vma_flags_t *vma_flags) { unsigned long new_flags, old_flags = READ_ONCE(folio->flags.f); @@ -3196,10 +3206,15 @@ static int folio_update_gen(struct folio *folio, int gen) /* see the comment on LRU_REFS_FLAGS */ if (!folio_test_referenced(folio) && !folio_test_workingset(folio)) { + /* Activate file-backed executable folios after first usage. */ + if (is_exec_file_folio(folio, vma_flags)) + goto promote; + set_mask_bits(&folio->flags.f, LRU_REFS_MASK, BIT(PG_referenced)); return -1; } +promote: do { /* lru_gen_del_folio() has isolated this page? */ if (!(old_flags & LRU_GEN_MASK)) @@ -3428,8 +3443,8 @@ static bool suitable_to_scan(int total, int young) return young * n >= total; } -static void walk_update_folio(struct lru_gen_mm_walk *walk, struct folio *folio, - int new_gen, bool dirty) +static void walk_update_folio(struct lru_gen_mm_walk *walk, struct vm_area_struct *vma, + struct folio *folio, int new_gen, bool dirty) { int old_gen; @@ -3442,10 +3457,10 @@ static void walk_update_folio(struct lru_gen_mm_walk *walk, struct folio *folio, folio_mark_dirty(folio); if (walk) { - old_gen = folio_update_gen(folio, new_gen); + old_gen = folio_update_gen(folio, new_gen, &vma->flags); if (old_gen >= 0 && old_gen != new_gen) update_batch_size(walk, folio, old_gen, new_gen); - } else if (lru_gen_set_refs(folio)) { + } else if (lru_gen_set_refs(folio, &vma->flags)) { old_gen = folio_lru_gen(folio); if (old_gen >= 0 && old_gen != new_gen) folio_activate(folio); @@ -3518,7 +3533,7 @@ static bool walk_pte_range(pmd_t *pmd, unsigned long start, unsigned long end, continue; if (last != folio) { - walk_update_folio(walk, last, gen, dirty); + walk_update_folio(walk, args->vma, last, gen, dirty); last = folio; dirty = false; @@ -3531,7 +3546,7 @@ static bool walk_pte_range(pmd_t *pmd, unsigned long start, unsigned long end, walk->mm_stats[MM_LEAF_YOUNG] += nr; } - walk_update_folio(walk, last, gen, dirty); + walk_update_folio(walk, args->vma, last, gen, dirty); last = NULL; if (i < PTRS_PER_PTE && get_next_vma(PMD_MASK, PAGE_SIZE, args, &start, &end)) @@ -3609,7 +3624,7 @@ static void walk_pmd_range_locked(pud_t *pud, unsigned long addr, struct vm_area goto next; if (last != folio) { - walk_update_folio(walk, last, gen, dirty); + walk_update_folio(walk, vma, last, gen, dirty); last = folio; dirty = false; @@ -3623,7 +3638,7 @@ static void walk_pmd_range_locked(pud_t *pud, unsigned long addr, struct vm_area i = i > MIN_LRU_BATCH ? 0 : find_next_bit(bitmap, MIN_LRU_BATCH, i) + 1; } while (i <= MIN_LRU_BATCH); - walk_update_folio(walk, last, gen, dirty); + walk_update_folio(walk, vma, last, gen, dirty); lazy_mmu_mode_disable(); spin_unlock(ptl); @@ -4258,7 +4273,7 @@ bool lru_gen_look_around(struct page_vma_mapped_walk *pvmw, unsigned int nr) continue; if (last != folio) { - walk_update_folio(walk, last, gen, dirty); + walk_update_folio(walk, vma, last, gen, dirty); last = folio; dirty = false; @@ -4270,7 +4285,7 @@ bool lru_gen_look_around(struct page_vma_mapped_walk *pvmw, unsigned int nr) young += nr; } - walk_update_folio(walk, last, gen, dirty); + walk_update_folio(walk, vma, last, gen, dirty); lazy_mmu_mode_disable(); -- 2.47.3 ^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v3 2/2] mm: mglru: promote mapped executable folios after first usage 2026-07-17 10:05 ` [PATCH v3 2/2] mm: mglru: promote mapped executable folios after first usage Baolin Wang @ 2026-07-17 12:44 ` Johannes Weiner 2026-07-17 12:58 ` Baolin Wang 0 siblings, 1 reply; 6+ messages in thread From: Johannes Weiner @ 2026-07-17 12:44 UTC (permalink / raw) To: Baolin Wang Cc: akpm, david, ljs, riel, liam, vbabka, harry, jannh, lance.yang, kasong, qi.zheng, shakeel.butt, baohua, axelrasmussen, yuanchu, weixugc, mhocko, linux-mm, linux-kernel On Fri, Jul 17, 2026 at 06:05:34PM +0800, Baolin Wang wrote: > Classical LRU protects mapped executable file folios through commit > 8cab4754d24a0 ("vmscan: make mapped executable pages the first class > citizen") and commit c909e99364c8 ("vmscan: activate executable pages > after first usage"), giving executable code a better chance to stay in > memory, avoiding IO thrashing and improving workload performance. > > However, MGLRU's protection of mapped executable file folios is less > reliable. Although shrink_folio_list() checks references, the access flag > of mapped executable file folios may have already been checked and > cleared by lru_gen_look_around() or walk_mm(). Additionally, > folio_update_gen() or lru_gen_set_refs() only sets the 'PG_referenced' > flag for mapped executable file folios, which causes shrink_folio_list() > to ignore the first usage of these mapped executable file folios and > reclaim them easily. > > Follow the classical LRU's logic, promoting mapped executable file folios > after their first usage in folio_update_gen() and lru_gen_set_refs(), > giving executable code a better chance to stay in memory. > > On my 32-core Arm machine, with the memcg limit set to 2G, running > 'make -j32' to build kernel showed some improvement in sys time. > > base patched > 9248.543s 7861.579s > > While we are at it, introduce a new helper to check mapped executable > file folios. > > Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Both patches contained herein look good: Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> [ Sorry ;-) Please don't mix refactoring work with functional changes. It's difficult to look through a sequence of diff hunks with more than one review narrative interleaved. ] > --- > mm/vmscan.c | 47 +++++++++++++++++++++++++++++++---------------- > 1 file changed, 31 insertions(+), 16 deletions(-) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index de62899c108d..1040bf9f96e8 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -268,6 +268,12 @@ static int sc_swappiness(struct scan_control *sc, struct mem_cgroup *memcg) > } > #endif > > +static inline bool is_exec_file_folio(const struct folio *folio, > + const vma_flags_t *vma_flags) > +{ > + return vma_flags_test(vma_flags, VMA_EXEC_BIT) && folio_is_file_lru(folio); > +} > + > static void set_task_reclaim_state(struct task_struct *task, > struct reclaim_state *rs) > { > @@ -835,11 +841,15 @@ enum folio_references { > * with PG_active set. In contrast, the aging (page table walk) path uses > * folio_update_gen(). > */ > -static bool lru_gen_set_refs(struct folio *folio) > +static bool lru_gen_set_refs(struct folio *folio, const vma_flags_t *vma_flags) > { > /* see the comment on LRU_REFS_FLAGS */ > if (!folio_test_referenced(folio) && !folio_test_workingset(folio)) { > set_mask_bits(&folio->flags.f, LRU_REFS_MASK, BIT(PG_referenced)); > + /* Activate file-backed executable folios after first usage. */ > + if (is_exec_file_folio(folio, vma_flags)) > + return true; > + > return false; > } > > @@ -851,7 +861,7 @@ static bool lru_gen_set_refs(struct folio *folio) > return true; > } > #else > -static bool lru_gen_set_refs(struct folio *folio) > +static bool lru_gen_set_refs(struct folio *folio, const vma_flags_t *vma_flags) > { > return false; > } > @@ -886,7 +896,7 @@ static enum folio_references folio_check_references(struct folio *folio, > if (!referenced_ptes) > return FOLIOREF_RECLAIM; > > - return lru_gen_set_refs(folio) ? FOLIOREF_ACTIVATE : FOLIOREF_KEEP; > + return lru_gen_set_refs(folio, &vma_flags) ? FOLIOREF_ACTIVATE : FOLIOREF_KEEP; > } > > referenced_folio = folio_test_clear_referenced(folio); > @@ -914,7 +924,7 @@ static enum folio_references folio_check_references(struct folio *folio, > /* > * Activate file-backed executable folios after first usage. > */ > - if (vma_flags_test(&vma_flags, VMA_EXEC_BIT) && folio_is_file_lru(folio)) > + if (is_exec_file_folio(folio, &vma_flags)) > return FOLIOREF_ACTIVATE; > > return FOLIOREF_KEEP; > @@ -2119,7 +2129,7 @@ static void shrink_active_list(unsigned long nr_to_scan, > * IO, plus JVM can create lots of anon VM_EXEC folios, > * so we ignore them here. > */ > - if (vma_flags_test(&vma_flags, VMA_EXEC_BIT) && folio_is_file_lru(folio)) { > + if (is_exec_file_folio(folio, &vma_flags)) { > nr_rotated += folio_nr_pages(folio); > list_add(&folio->lru, &l_active); > continue; > @@ -3188,7 +3198,7 @@ static bool positive_ctrl_err(struct ctrl_pos *sp, struct ctrl_pos *pv) > ******************************************************************************/ > > /* promote pages accessed through page tables */ > -static int folio_update_gen(struct folio *folio, int gen) > +static int folio_update_gen(struct folio *folio, int gen, const vma_flags_t *vma_flags) > { > unsigned long new_flags, old_flags = READ_ONCE(folio->flags.f); > > @@ -3196,10 +3206,15 @@ static int folio_update_gen(struct folio *folio, int gen) > > /* see the comment on LRU_REFS_FLAGS */ > if (!folio_test_referenced(folio) && !folio_test_workingset(folio)) { > + /* Activate file-backed executable folios after first usage. */ > + if (is_exec_file_folio(folio, vma_flags)) > + goto promote; > + > set_mask_bits(&folio->flags.f, LRU_REFS_MASK, BIT(PG_referenced)); > return -1; > } > > +promote: > do { > /* lru_gen_del_folio() has isolated this page? */ > if (!(old_flags & LRU_GEN_MASK)) > @@ -3428,8 +3443,8 @@ static bool suitable_to_scan(int total, int young) > return young * n >= total; > } > > -static void walk_update_folio(struct lru_gen_mm_walk *walk, struct folio *folio, > - int new_gen, bool dirty) > +static void walk_update_folio(struct lru_gen_mm_walk *walk, struct vm_area_struct *vma, > + struct folio *folio, int new_gen, bool dirty) > { > int old_gen; > > @@ -3442,10 +3457,10 @@ static void walk_update_folio(struct lru_gen_mm_walk *walk, struct folio *folio, > folio_mark_dirty(folio); > > if (walk) { > - old_gen = folio_update_gen(folio, new_gen); > + old_gen = folio_update_gen(folio, new_gen, &vma->flags); > if (old_gen >= 0 && old_gen != new_gen) > update_batch_size(walk, folio, old_gen, new_gen); > - } else if (lru_gen_set_refs(folio)) { > + } else if (lru_gen_set_refs(folio, &vma->flags)) { > old_gen = folio_lru_gen(folio); > if (old_gen >= 0 && old_gen != new_gen) > folio_activate(folio); > @@ -3518,7 +3533,7 @@ static bool walk_pte_range(pmd_t *pmd, unsigned long start, unsigned long end, > continue; > > if (last != folio) { > - walk_update_folio(walk, last, gen, dirty); > + walk_update_folio(walk, args->vma, last, gen, dirty); > > last = folio; > dirty = false; > @@ -3531,7 +3546,7 @@ static bool walk_pte_range(pmd_t *pmd, unsigned long start, unsigned long end, > walk->mm_stats[MM_LEAF_YOUNG] += nr; > } > > - walk_update_folio(walk, last, gen, dirty); > + walk_update_folio(walk, args->vma, last, gen, dirty); > last = NULL; > > if (i < PTRS_PER_PTE && get_next_vma(PMD_MASK, PAGE_SIZE, args, &start, &end)) > @@ -3609,7 +3624,7 @@ static void walk_pmd_range_locked(pud_t *pud, unsigned long addr, struct vm_area > goto next; > > if (last != folio) { > - walk_update_folio(walk, last, gen, dirty); > + walk_update_folio(walk, vma, last, gen, dirty); > > last = folio; > dirty = false; > @@ -3623,7 +3638,7 @@ static void walk_pmd_range_locked(pud_t *pud, unsigned long addr, struct vm_area > i = i > MIN_LRU_BATCH ? 0 : find_next_bit(bitmap, MIN_LRU_BATCH, i) + 1; > } while (i <= MIN_LRU_BATCH); > > - walk_update_folio(walk, last, gen, dirty); > + walk_update_folio(walk, vma, last, gen, dirty); > > lazy_mmu_mode_disable(); > spin_unlock(ptl); > @@ -4258,7 +4273,7 @@ bool lru_gen_look_around(struct page_vma_mapped_walk *pvmw, unsigned int nr) > continue; > > if (last != folio) { > - walk_update_folio(walk, last, gen, dirty); > + walk_update_folio(walk, vma, last, gen, dirty); > > last = folio; > dirty = false; > @@ -4270,7 +4285,7 @@ bool lru_gen_look_around(struct page_vma_mapped_walk *pvmw, unsigned int nr) > young += nr; > } > > - walk_update_folio(walk, last, gen, dirty); > + walk_update_folio(walk, vma, last, gen, dirty); > > lazy_mmu_mode_disable(); > > -- > 2.47.3 > ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v3 2/2] mm: mglru: promote mapped executable folios after first usage 2026-07-17 12:44 ` Johannes Weiner @ 2026-07-17 12:58 ` Baolin Wang 0 siblings, 0 replies; 6+ messages in thread From: Baolin Wang @ 2026-07-17 12:58 UTC (permalink / raw) To: Johannes Weiner Cc: akpm, david, ljs, riel, liam, vbabka, harry, jannh, lance.yang, kasong, qi.zheng, shakeel.butt, baohua, axelrasmussen, yuanchu, weixugc, mhocko, linux-mm, linux-kernel On 7/17/26 8:44 PM, Johannes Weiner wrote: > On Fri, Jul 17, 2026 at 06:05:34PM +0800, Baolin Wang wrote: >> Classical LRU protects mapped executable file folios through commit >> 8cab4754d24a0 ("vmscan: make mapped executable pages the first class >> citizen") and commit c909e99364c8 ("vmscan: activate executable pages >> after first usage"), giving executable code a better chance to stay in >> memory, avoiding IO thrashing and improving workload performance. >> >> However, MGLRU's protection of mapped executable file folios is less >> reliable. Although shrink_folio_list() checks references, the access flag >> of mapped executable file folios may have already been checked and >> cleared by lru_gen_look_around() or walk_mm(). Additionally, >> folio_update_gen() or lru_gen_set_refs() only sets the 'PG_referenced' >> flag for mapped executable file folios, which causes shrink_folio_list() >> to ignore the first usage of these mapped executable file folios and >> reclaim them easily. >> >> Follow the classical LRU's logic, promoting mapped executable file folios >> after their first usage in folio_update_gen() and lru_gen_set_refs(), >> giving executable code a better chance to stay in memory. >> >> On my 32-core Arm machine, with the memcg limit set to 2G, running >> 'make -j32' to build kernel showed some improvement in sys time. >> >> base patched >> 9248.543s 7861.579s >> >> While we are at it, introduce a new helper to check mapped executable >> file folios. >> >> Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> > > Both patches contained herein look good: > > Acked-by: Johannes Weiner <hannes@cmpxchg.org> > Acked-by: Johannes Weiner <hannes@cmpxchg.org> Thanks for reviewing. > [ Sorry ;-) Please don't mix refactoring work with functional > changes. It's difficult to look through a sequence of diff hunks > with more than one review narrative interleaved. ] Ha, sure. Sorry for mixing in a helper replacement. I'll split it out into a separate patch next time. :) ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2026-07-17 12:58 UTC | newest] Thread overview: 6+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2026-07-17 10:05 [PATCH v3 0/2] promote mapped executable folios after first usage for MGLRU Baolin Wang 2026-07-17 10:05 ` [PATCH v3 1/2] mm: vmscan: convert folio_referenced() to use vma_flags_t Baolin Wang 2026-07-17 12:34 ` Johannes Weiner 2026-07-17 10:05 ` [PATCH v3 2/2] mm: mglru: promote mapped executable folios after first usage Baolin Wang 2026-07-17 12:44 ` Johannes Weiner 2026-07-17 12:58 ` Baolin Wang
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