bianbu-repo-mirror/bianbu-linux-6.6
1
0
Fork 0
mirror of https://gitee.com/bianbu-linux/linux-6.6 synced 2025-04-24 14:07:52 -04:00
Code Issues Projects Releases Packages Wiki Activity Actions

mm/munlock: protect the per-CPU pagevec by a local_lock_t

Browse source 
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>
This commit is contained in:
Sebastian Andrzej Siewior 2022-04-01 11:28:33 -07:00 • committed by Linus Torvalds
parent 577e9846f8
commit adb11e78c5
6 changed files with 47 additions and 16 deletions
Download patch file Download diff file Expand all files Collapse all files

4
mm/swap.c
View file

@ -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