diff options
author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2022-04-01 11:28:33 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-04-01 11:46:09 -0700 |
commit | adb11e78c5dc5e26774acb05f983da36447f7911 (patch) | |
tree | bacf697b157f86712edffebbfd7c08aa7d83e966 /mm/swap.c | |
parent | 577e9846f8a9e7b09cd356ae0d59a66e19402e8b (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.c | 4 |
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 |