Re: [PATCH v3 23/30] mm: do not open-code lruvec lock
From: Qi Zheng
Date: Thu Jan 15 2026 - 04:32:26 EST
On 1/15/26 5:26 PM, Baoquan He wrote:
On 01/14/26 at 07:32pm, Qi Zheng wrote:
From: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx>~~ typo, 'no'?
Now we have lruvec_unlock(), lruvec_unlock_irq() and
lruvec_unlock_irqrestore(), but not the paired lruvec_lock(),
lruvec_lock_irq() and lruvec_lock_irqsave().
There is currently no use case for lruvec_lock_irqsave(), so only
introduce lruvec_lock() and lruvec_lock_irq(), and change all open-code
I didn't see lruvec_lock() is introduced in this patch, do I miss
anthing?
I forgot to update commit message when I deleted lruvec_lock(), will
modify it in the next version.
Thanks!
places to use these helper function. This looks cleaner and prepares for
reparenting LRU pages, preventing user from missing RCU lock calls due to
open-code lruvec lock.
Signed-off-by: Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx>
---
include/linux/memcontrol.h | 5 +++++
mm/vmscan.c | 38 +++++++++++++++++++-------------------
2 files changed, 24 insertions(+), 19 deletions(-)
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index f1556759d0d3f..4b6f20dc694ba 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -1499,6 +1499,11 @@ static inline struct lruvec *parent_lruvec(struct lruvec *lruvec)
return mem_cgroup_lruvec(memcg, lruvec_pgdat(lruvec));
}
+static inline void lruvec_lock_irq(struct lruvec *lruvec)
+{
+ spin_lock_irq(&lruvec->lru_lock);
+}
+
static inline void lruvec_unlock(struct lruvec *lruvec)
{
spin_unlock(&lruvec->lru_lock);
diff --git a/mm/vmscan.c b/mm/vmscan.c
index f206d4dac9e77..c48ff6e05e004 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2020,7 +2020,7 @@ static unsigned long shrink_inactive_list(unsigned long nr_to_scan,
lru_add_drain();
- spin_lock_irq(&lruvec->lru_lock);
+ lruvec_lock_irq(lruvec);
nr_taken = isolate_lru_folios(nr_to_scan, lruvec, &folio_list,
&nr_scanned, sc, lru);
@@ -2032,7 +2032,7 @@ static unsigned long shrink_inactive_list(unsigned long nr_to_scan,
count_memcg_events(lruvec_memcg(lruvec), item, nr_scanned);
__count_vm_events(PGSCAN_ANON + file, nr_scanned);
- spin_unlock_irq(&lruvec->lru_lock);
+ lruvec_unlock_irq(lruvec);
if (nr_taken == 0)
return 0;
@@ -2051,7 +2051,7 @@ static unsigned long shrink_inactive_list(unsigned long nr_to_scan,
count_memcg_events(lruvec_memcg(lruvec), item, nr_reclaimed);
count_vm_events(PGSTEAL_ANON + file, nr_reclaimed);
- spin_lock_irq(&lruvec->lru_lock);
+ lruvec_lock_irq(lruvec);
lru_note_cost_unlock_irq(lruvec, file, stat.nr_pageout,
nr_scanned - nr_reclaimed);
@@ -2130,7 +2130,7 @@ static void shrink_active_list(unsigned long nr_to_scan,
lru_add_drain();
- spin_lock_irq(&lruvec->lru_lock);
+ lruvec_lock_irq(lruvec);
nr_taken = isolate_lru_folios(nr_to_scan, lruvec, &l_hold,
&nr_scanned, sc, lru);
@@ -2141,7 +2141,7 @@ static void shrink_active_list(unsigned long nr_to_scan,
__count_vm_events(PGREFILL, nr_scanned);
count_memcg_events(lruvec_memcg(lruvec), PGREFILL, nr_scanned);
- spin_unlock_irq(&lruvec->lru_lock);
+ lruvec_unlock_irq(lruvec);
while (!list_empty(&l_hold)) {
struct folio *folio;
@@ -2197,7 +2197,7 @@ static void shrink_active_list(unsigned long nr_to_scan,
count_memcg_events(lruvec_memcg(lruvec), PGDEACTIVATE, nr_deactivate);
mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, -nr_taken);
- spin_lock_irq(&lruvec->lru_lock);
+ lruvec_lock_irq(lruvec);
lru_note_cost_unlock_irq(lruvec, file, 0, nr_rotated);
trace_mm_vmscan_lru_shrink_active(pgdat->node_id, nr_taken, nr_activate,
nr_deactivate, nr_rotated, sc->priority, file);
@@ -3832,9 +3832,9 @@ static void walk_mm(struct mm_struct *mm, struct lru_gen_mm_walk *walk)
}
if (walk->batched) {
- spin_lock_irq(&lruvec->lru_lock);
+ lruvec_lock_irq(lruvec);
reset_batch_size(walk);
- spin_unlock_irq(&lruvec->lru_lock);
+ lruvec_unlock_irq(lruvec);
}
cond_resched();
@@ -3993,7 +3993,7 @@ static bool inc_max_seq(struct lruvec *lruvec, unsigned long seq, int swappiness
if (seq < READ_ONCE(lrugen->max_seq))
return false;
- spin_lock_irq(&lruvec->lru_lock);
+ lruvec_lock_irq(lruvec);
VM_WARN_ON_ONCE(!seq_is_valid(lruvec));
@@ -4008,7 +4008,7 @@ static bool inc_max_seq(struct lruvec *lruvec, unsigned long seq, int swappiness
if (inc_min_seq(lruvec, type, swappiness))
continue;
- spin_unlock_irq(&lruvec->lru_lock);
+ lruvec_unlock_irq(lruvec);
cond_resched();
goto restart;
}
@@ -4043,7 +4043,7 @@ static bool inc_max_seq(struct lruvec *lruvec, unsigned long seq, int swappiness
/* make sure preceding modifications appear */
smp_store_release(&lrugen->max_seq, lrugen->max_seq + 1);
unlock:
- spin_unlock_irq(&lruvec->lru_lock);
+ lruvec_unlock_irq(lruvec);
return success;
}
@@ -4739,7 +4739,7 @@ static int evict_folios(unsigned long nr_to_scan, struct lruvec *lruvec,
struct mem_cgroup *memcg = lruvec_memcg(lruvec);
struct pglist_data *pgdat = lruvec_pgdat(lruvec);
- spin_lock_irq(&lruvec->lru_lock);
+ lruvec_lock_irq(lruvec);
scanned = isolate_folios(nr_to_scan, lruvec, sc, swappiness, &type, &list);
@@ -4748,7 +4748,7 @@ static int evict_folios(unsigned long nr_to_scan, struct lruvec *lruvec,
if (evictable_min_seq(lrugen->min_seq, swappiness) + MIN_NR_GENS > lrugen->max_seq)
scanned = 0;
- spin_unlock_irq(&lruvec->lru_lock);
+ lruvec_unlock_irq(lruvec);
if (list_empty(&list))
return scanned;
@@ -4786,9 +4786,9 @@ static int evict_folios(unsigned long nr_to_scan, struct lruvec *lruvec,
walk = current->reclaim_state->mm_walk;
if (walk && walk->batched) {
walk->lruvec = lruvec;
- spin_lock_irq(&lruvec->lru_lock);
+ lruvec_lock_irq(lruvec);
reset_batch_size(walk);
- spin_unlock_irq(&lruvec->lru_lock);
+ lruvec_unlock_irq(lruvec);
}
mod_lruvec_state(lruvec, PGDEMOTE_KSWAPD + reclaimer_offset(sc),
@@ -5226,7 +5226,7 @@ static void lru_gen_change_state(bool enabled)
for_each_node(nid) {
struct lruvec *lruvec = get_lruvec(memcg, nid);
- spin_lock_irq(&lruvec->lru_lock);
+ lruvec_lock_irq(lruvec);
VM_WARN_ON_ONCE(!seq_is_valid(lruvec));
VM_WARN_ON_ONCE(!state_is_valid(lruvec));
@@ -5234,12 +5234,12 @@ static void lru_gen_change_state(bool enabled)
lruvec->lrugen.enabled = enabled;
while (!(enabled ? fill_evictable(lruvec) : drain_evictable(lruvec))) {
- spin_unlock_irq(&lruvec->lru_lock);
+ lruvec_unlock_irq(lruvec);
cond_resched();
- spin_lock_irq(&lruvec->lru_lock);
+ lruvec_lock_irq(lruvec);
}
- spin_unlock_irq(&lruvec->lru_lock);
+ lruvec_unlock_irq(lruvec);
}
cond_resched();
--
2.20.1