summaryrefslogtreecommitdiff
path: root/mm/swap.c
diff options
context:
space:
mode:
authorSebastian Andrzej Siewior <bigeasy@linutronix.de>2022-04-01 11:28:33 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2022-04-01 11:46:09 -0700
commitadb11e78c5dc5e26774acb05f983da36447f7911 (patch)
treebacf697b157f86712edffebbfd7c08aa7d83e966 /mm/swap.c
parent577e9846f8a9e7b09cd356ae0d59a66e19402e8b (diff)
mm/munlock: protect the per-CPU pagevec by a local_lock_t
The access to mlock_pvec is protected by disabling preemption via get_cpu_var() or implicit by having preemption disabled by the caller (in mlock_page_drain() case). This breaks on PREEMPT_RT since folio_lruvec_lock_irq() acquires a sleeping lock in this section. Create struct mlock_pvec which consits of the local_lock_t and the pagevec. Acquire the local_lock() before accessing the per-CPU pagevec. Replace mlock_page_drain() with a _local() version which is invoked on the local CPU and acquires the local_lock_t and a _remote() version which uses the pagevec from a remote CPU which offline. Link: https://lkml.kernel.org/r/YjizWi9IY0mpvIfb@linutronix.de Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Hugh Dickins <hughd@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Matthew Wilcox <willy@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/swap.c')
-rw-r--r--mm/swap.c4
1 files changed, 3 insertions, 1 deletions
diff --git a/mm/swap.c b/mm/swap.c
index bceff0cb559c..7e320ec08c6a 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -624,7 +624,6 @@ void lru_add_drain_cpu(int cpu)
pagevec_lru_move_fn(pvec, lru_lazyfree_fn);
activate_page_drain(cpu);
- mlock_page_drain(cpu);
}
/**
@@ -706,6 +705,7 @@ void lru_add_drain(void)
local_lock(&lru_pvecs.lock);
lru_add_drain_cpu(smp_processor_id());
local_unlock(&lru_pvecs.lock);
+ mlock_page_drain_local();
}
/*
@@ -720,6 +720,7 @@ static void lru_add_and_bh_lrus_drain(void)
lru_add_drain_cpu(smp_processor_id());
local_unlock(&lru_pvecs.lock);
invalidate_bh_lrus_cpu();
+ mlock_page_drain_local();
}
void lru_add_drain_cpu_zone(struct zone *zone)
@@ -728,6 +729,7 @@ void lru_add_drain_cpu_zone(struct zone *zone)
lru_add_drain_cpu(smp_processor_id());
drain_local_pages(zone);
local_unlock(&lru_pvecs.lock);
+ mlock_page_drain_local();
}
#ifdef CONFIG_SMP