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| author | Thomas Gleixner <tglx@linutronix.de> | 2023-05-25 14:57:08 +0200 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-06-10 01:25:41 +0200 |
| commit | 7f48121e9fa82bdaf0bd0f7a7e49f48803c6c0e8 (patch) | |
| tree | f6dbc6ad049321e6ce83e3f7d704745ee1d3a5fa /mm/vmalloc.c | |
| parent | mm/vmalloc: check free space in vmap_block lockless (diff) | |
| download | linux-7f48121e9fa82bdaf0bd0f7a7e49f48803c6c0e8.tar.xz linux-7f48121e9fa82bdaf0bd0f7a7e49f48803c6c0e8.zip | |
mm/vmalloc: add missing READ/WRITE_ONCE() annotations
purge_fragmented_blocks() accesses vmap_block::free and vmap_block::dirty
lockless for a quick check.
Add the missing READ/WRITE_ONCE() annotations.
Link: https://lkml.kernel.org/r/20230525124504.807356682@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/vmalloc.c')
| -rw-r--r-- | mm/vmalloc.c | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 679112e2ffd2..f643c7286c7a 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -2094,9 +2094,9 @@ static bool purge_fragmented_block(struct vmap_block *vb, return false; /* prevent further allocs after releasing lock */ - vb->free = 0; + WRITE_ONCE(vb->free, 0); /* prevent purging it again */ - vb->dirty = VMAP_BBMAP_BITS; + WRITE_ONCE(vb->dirty, VMAP_BBMAP_BITS); vb->dirty_min = 0; vb->dirty_max = VMAP_BBMAP_BITS; spin_lock(&vbq->lock); @@ -2124,8 +2124,11 @@ static void purge_fragmented_blocks(int cpu) rcu_read_lock(); list_for_each_entry_rcu(vb, &vbq->free, free_list) { - if (vb->free + vb->dirty != VMAP_BBMAP_BITS || - vb->dirty == VMAP_BBMAP_BITS) + unsigned long free = READ_ONCE(vb->free); + unsigned long dirty = READ_ONCE(vb->dirty); + + if (free + dirty != VMAP_BBMAP_BITS || + dirty == VMAP_BBMAP_BITS) continue; spin_lock(&vb->lock); @@ -2233,7 +2236,7 @@ static void vb_free(unsigned long addr, unsigned long size) vb->dirty_min = min(vb->dirty_min, offset); vb->dirty_max = max(vb->dirty_max, offset + (1UL << order)); - vb->dirty += 1UL << order; + WRITE_ONCE(vb->dirty, vb->dirty + (1UL << order)); if (vb->dirty == VMAP_BBMAP_BITS) { BUG_ON(vb->free); spin_unlock(&vb->lock); |