Date:   Mon, 27 Feb 2023 09:36:03 -0800
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Subject: [PATCH v4 04/33] maple_tree: remove extra smp_wmb() from mas_dead_leaves()
From:   Suren Baghdasaryan <surenb@google.com>
To:     akpm@linux-foundation.org
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        vbabka@suse.cz, hannes@cmpxchg.org, mgorman@techsingularity.net,
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        Liam Howlett <Liam.Howlett@oracle.com>,
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From: Liam Howlett <Liam.Howlett@oracle.com>

The call to mte_set_dead_node() before the smp_wmb() already calls
smp_wmb() so this is not needed.  This is an optimization for the RCU
mode of the maple tree.

Fixes: 54a611b60590 ("Maple Tree: add new data structure")
Signed-off-by: Liam Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
---
 lib/maple_tree.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 44d6ce30b28e..3d5ab02f981a 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -5517,7 +5517,6 @@ unsigned char mas_dead_leaves(struct ma_state *mas, void __rcu **slots,
 			break;
 
 		mte_set_node_dead(entry);
-		smp_wmb(); /* Needed for RCU */
 		node->type = type;
 		rcu_assign_pointer(slots[offset], node);
 	}
-- 
2.39.2.722.g9855ee24e9-goog