linux-kernel - [PATCH v2 2/3] IB/core: Shuffle locks in ib_port

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu,  3 Jun 2021 12:20:23 +0530
From:   Anand Khoje <anand.a.khoje@...cle.com>
To:     linux-rdma@...r.kernel.org, linux-kernel@...r.kernel.org
Cc:     dledford@...hat.com, jgg@...pe.ca, haakon.bugge@...cle.com,
        leon@...nel.org
Subject: [PATCH v2 2/3] IB/core: Shuffle locks in ib_port_data to save memory

pahole shows two 4-byte holes in struct ib_port_data after
pkey_list_lock and netdev_lock respectively.

Shuffling the netdev_lock to be after pkey_list_lock, this 
shaves off eight bytes from the struct.

Suggested-by: Haakon Bugge <haakon.bugge@...cle.com>
Signed-off-by: Anand Khoje <anand.a.khoje@...cle.com>
---
 include/rdma/ib_verbs.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 7e2f369..41cbec5 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -2175,11 +2175,13 @@ struct ib_port_data {
 	struct ib_port_immutable immutable;
 
 	spinlock_t pkey_list_lock;
+
+	spinlock_t netdev_lock;
+
 	struct list_head pkey_list;
 
 	struct ib_port_cache cache;
 
-	spinlock_t netdev_lock;
 	struct net_device __rcu *netdev;
 	struct hlist_node ndev_hash_link;
 	struct rdma_port_counter port_counter;
-- 
1.8.3.1