LVS
lvs-devel
Google
 
Web LinuxVirtualServer.org

[PATCH v4 1/8] net: Remove the now superfluous sentinel elements from ct

To: "David S. Miller" <davem@xxxxxxxxxxxxx>, Eric Dumazet <edumazet@xxxxxxxxxx>, Jakub Kicinski <kuba@xxxxxxxxxx>, Paolo Abeni <pabeni@xxxxxxxxxx>, Alexander Aring <alex.aring@xxxxxxxxx>, Stefan Schmidt <stefan@xxxxxxxxxxxxxxxxxx>, Miquel Raynal <miquel.raynal@xxxxxxxxxxx>, David Ahern <dsahern@xxxxxxxxxx>, Steffen Klassert <steffen.klassert@xxxxxxxxxxx>, Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>, Matthieu Baerts <matttbe@xxxxxxxxxx>, Mat Martineau <martineau@xxxxxxxxxx>, Geliang Tang <geliang@xxxxxxxxxx>, Ralf Baechle <ralf@xxxxxxxxxxxxxx>, Remi Denis-Courmont <courmisch@xxxxxxxxx>, Allison Henderson <allison.henderson@xxxxxxxxxx>, David Howells <dhowells@xxxxxxxxxx>, Marc Dionne <marc.dionne@xxxxxxxxxxxx>, Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx>, Xin Long <lucien.xin@xxxxxxxxx>, Wenjia Zhang <wenjia@xxxxxxxxxxxxx>, Jan Karcher <jaka@xxxxxxxxxxxxx>, "D. Wythe" <alibuda@xxxxxxxxxxxxxxxxx>, Tony Lu <tonylu@xxxxxxxxxxxxxxxxx>, Wen Gu <guwen@xxxxxxxxxxxxxxxxx>, Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>, Anna Schumaker <anna@xxxxxxxxxx>, Chuck Lever <chuck.lever@xxxxxxxxxx>, Jeff Layton <jlayton@xxxxxxxxxx>, Neil Brown <neilb@xxxxxxx>, Olga Kornievskaia <kolga@xxxxxxxxxx>, Dai Ngo <Dai.Ngo@xxxxxxxxxx>, Tom Talpey <tom@xxxxxxxxxx>, Jon Maloy <jmaloy@xxxxxxxxxx>, Ying Xue <ying.xue@xxxxxxxxxxxxx>, Martin Schiller <ms@xxxxxxxxxx>, Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>, Jozsef Kadlecsik <kadlec@xxxxxxxxxxxxx>, Florian Westphal <fw@xxxxxxxxx>, Roopa Prabhu <roopa@xxxxxxxxxx>, Nikolay Aleksandrov <razor@xxxxxxxxxxxxx>, Simon Horman <horms@xxxxxxxxxxxx>, Julian Anastasov <ja@xxxxxx>, Joerg Reuter <jreuter@xxxxxxxx>, Luis Chamberlain <mcgrof@xxxxxxxxxx>, Kees Cook <keescook@xxxxxxxxxxxx>
Subject: [PATCH v4 1/8] net: Remove the now superfluous sentinel elements from ctl_table array
Cc: netdev@xxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx, dccp@xxxxxxxxxxxxxxx, linux-wpan@xxxxxxxxxxxxxxx, mptcp@xxxxxxxxxxxxxxx, linux-hams@xxxxxxxxxxxxxxx, linux-rdma@xxxxxxxxxxxxxxx, rds-devel@xxxxxxxxxxxxxx, linux-afs@xxxxxxxxxxxxxxxxxxx, linux-sctp@xxxxxxxxxxxxxxx, linux-s390@xxxxxxxxxxxxxxx, linux-nfs@xxxxxxxxxxxxxxx, tipc-discussion@xxxxxxxxxxxxxxxxxxxxx, linux-x25@xxxxxxxxxxxxxxx, netfilter-devel@xxxxxxxxxxxxxxx, coreteam@xxxxxxxxxxxxx, bridge@xxxxxxxxxxxxxxx, lvs-devel@xxxxxxxxxxxxxxx, Joel Granados <j.granados@xxxxxxxxxxx>
From: Joel Granados via B4 Relay <devnull+j.granados.samsung.com@xxxxxxxxxx>
Date: Thu, 25 Apr 2024 14:02:59 +0200
From: Joel Granados <j.granados@xxxxxxxxxxx>

This commit comes at the tail end of a greater effort to remove the
empty elements at the end of the ctl_table arrays (sentinels) which
will reduce the overall build time size of the kernel and run time
memory bloat by ~64 bytes per sentinel (further information Link :
https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@xxxxxxxxxxxxxxxxxxxxxx/)

* Remove sentinel element from ctl_table structs.
* Remove the zeroing out of an array element (to make it look like a
  sentinel) in neigh_sysctl_register and lowpan_frags_ns_sysctl_register
  This is not longer needed and is safe after commit c899710fe7f9
  ("networking: Update to register_net_sysctl_sz") added the array size
  to the ctl_table registration.
* Replace the for loop stop condition in sysctl_core_net_init that tests
  for procname == NULL with one that depends on array size
* Removed the "-1" in mpls_net_init that adjusted for having an extra
  empty element when looping over ctl_table arrays
* Use a table_size variable to keep the value of ARRAY_SIZE

Signed-off-by: Joel Granados <j.granados@xxxxxxxxxxx>
---
 net/core/neighbour.c                |  5 +----
 net/core/sysctl_net_core.c          | 12 +++++-------
 net/dccp/sysctl.c                   |  2 --
 net/ieee802154/6lowpan/reassembly.c |  6 +-----
 net/mpls/af_mpls.c                  | 12 ++++++------
 net/unix/sysctl_net_unix.c          |  1 -
 6 files changed, 13 insertions(+), 25 deletions(-)

diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index 552719c3bbc3..b0327402b3e6 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -3728,7 +3728,7 @@ static int neigh_proc_base_reachable_time(struct 
ctl_table *ctl, int write,
 
 static struct neigh_sysctl_table {
        struct ctl_table_header *sysctl_header;
-       struct ctl_table neigh_vars[NEIGH_VAR_MAX + 1];
+       struct ctl_table neigh_vars[NEIGH_VAR_MAX];
 } neigh_sysctl_template __read_mostly = {
        .neigh_vars = {
                NEIGH_SYSCTL_ZERO_INTMAX_ENTRY(MCAST_PROBES, "mcast_solicit"),
@@ -3779,7 +3779,6 @@ static struct neigh_sysctl_table {
                        .extra2         = SYSCTL_INT_MAX,
                        .proc_handler   = proc_dointvec_minmax,
                },
-               {},
        },
 };
 
@@ -3807,8 +3806,6 @@ int neigh_sysctl_register(struct net_device *dev, struct 
neigh_parms *p,
        if (dev) {
                dev_name_source = dev->name;
                /* Terminate the table early */
-               memset(&t->neigh_vars[NEIGH_VAR_GC_INTERVAL], 0,
-                      sizeof(t->neigh_vars[NEIGH_VAR_GC_INTERVAL]));
                neigh_vars_size = NEIGH_VAR_BASE_REACHABLE_TIME_MS + 1;
        } else {
                struct neigh_table *tbl = p->tbl;
diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c
index 6973dda3abda..a84690b13bb9 100644
--- a/net/core/sysctl_net_core.c
+++ b/net/core/sysctl_net_core.c
@@ -660,7 +660,6 @@ static struct ctl_table net_core_table[] = {
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = SYSCTL_ZERO,
        },
-       { }
 };
 
 static struct ctl_table netns_core_table[] = {
@@ -697,7 +696,6 @@ static struct ctl_table netns_core_table[] = {
                .extra2         = SYSCTL_ONE,
                .proc_handler   = proc_dou8vec_minmax,
        },
-       { }
 };
 
 static int __init fb_tunnels_only_for_init_net_sysctl_setup(char *str)
@@ -715,7 +713,8 @@ __setup("fb_tunnels=", 
fb_tunnels_only_for_init_net_sysctl_setup);
 
 static __net_init int sysctl_core_net_init(struct net *net)
 {
-       struct ctl_table *tbl, *tmp;
+       size_t table_size = ARRAY_SIZE(netns_core_table);
+       struct ctl_table *tbl;
 
        tbl = netns_core_table;
        if (!net_eq(net, &init_net)) {
@@ -723,12 +722,11 @@ static __net_init int sysctl_core_net_init(struct net 
*net)
                if (tbl == NULL)
                        goto err_dup;
 
-               for (tmp = tbl; tmp->procname; tmp++)
-                       tmp->data += (char *)net - (char *)&init_net;
+               for (int i = 0; i < table_size; ++i)
+                       (tbl + i)->data += (char *)net - (char *)&init_net;
        }
 
-       net->core.sysctl_hdr = register_net_sysctl_sz(net, "net/core", tbl,
-                                                     
ARRAY_SIZE(netns_core_table));
+       net->core.sysctl_hdr = register_net_sysctl_sz(net, "net/core", tbl, 
table_size);
        if (net->core.sysctl_hdr == NULL)
                goto err_reg;
 
diff --git a/net/dccp/sysctl.c b/net/dccp/sysctl.c
index ee8d4f5afa72..3fc474d6e57d 100644
--- a/net/dccp/sysctl.c
+++ b/net/dccp/sysctl.c
@@ -90,8 +90,6 @@ static struct ctl_table dccp_default_table[] = {
                .mode           = 0644,
                .proc_handler   = proc_dointvec_ms_jiffies,
        },
-
-       { }
 };
 
 static struct ctl_table_header *dccp_table_header;
diff --git a/net/ieee802154/6lowpan/reassembly.c 
b/net/ieee802154/6lowpan/reassembly.c
index 6dd960ec558c..09b18ee6df00 100644
--- a/net/ieee802154/6lowpan/reassembly.c
+++ b/net/ieee802154/6lowpan/reassembly.c
@@ -338,7 +338,6 @@ static struct ctl_table lowpan_frags_ns_ctl_table[] = {
                .mode           = 0644,
                .proc_handler   = proc_dointvec_jiffies,
        },
-       { }
 };
 
 /* secret interval has been deprecated */
@@ -351,7 +350,6 @@ static struct ctl_table lowpan_frags_ctl_table[] = {
                .mode           = 0644,
                .proc_handler   = proc_dointvec_jiffies,
        },
-       { }
 };
 
 static int __net_init lowpan_frags_ns_sysctl_register(struct net *net)
@@ -370,10 +368,8 @@ static int __net_init 
lowpan_frags_ns_sysctl_register(struct net *net)
                        goto err_alloc;
 
                /* Don't export sysctls to unprivileged users */
-               if (net->user_ns != &init_user_ns) {
-                       table[0].procname = NULL;
+               if (net->user_ns != &init_user_ns)
                        table_size = 0;
-               }
        }
 
        table[0].data   = &ieee802154_lowpan->fqdir->high_thresh;
diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c
index 6dab883a08dd..1d15081090be 100644
--- a/net/mpls/af_mpls.c
+++ b/net/mpls/af_mpls.c
@@ -1393,13 +1393,13 @@ static const struct ctl_table mpls_dev_table[] = {
                .proc_handler   = mpls_conf_proc,
                .data           = MPLS_PERDEV_SYSCTL_OFFSET(input_enabled),
        },
-       { }
 };
 
 static int mpls_dev_sysctl_register(struct net_device *dev,
                                    struct mpls_dev *mdev)
 {
        char path[sizeof("net/mpls/conf/") + IFNAMSIZ];
+       size_t table_size = ARRAY_SIZE(mpls_dev_table);
        struct net *net = dev_net(dev);
        struct ctl_table *table;
        int i;
@@ -1411,7 +1411,7 @@ static int mpls_dev_sysctl_register(struct net_device 
*dev,
        /* Table data contains only offsets relative to the base of
         * the mdev at this point, so make them absolute.
         */
-       for (i = 0; i < ARRAY_SIZE(mpls_dev_table); i++) {
+       for (i = 0; i < table_size; i++) {
                table[i].data = (char *)mdev + (uintptr_t)table[i].data;
                table[i].extra1 = mdev;
                table[i].extra2 = net;
@@ -1419,8 +1419,7 @@ static int mpls_dev_sysctl_register(struct net_device 
*dev,
 
        snprintf(path, sizeof(path), "net/mpls/conf/%s", dev->name);
 
-       mdev->sysctl = register_net_sysctl_sz(net, path, table,
-                                             ARRAY_SIZE(mpls_dev_table));
+       mdev->sysctl = register_net_sysctl_sz(net, path, table, table_size);
        if (!mdev->sysctl)
                goto free;
 
@@ -2674,6 +2673,7 @@ static const struct ctl_table mpls_table[] = {
 
 static int mpls_net_init(struct net *net)
 {
+       size_t table_size = ARRAY_SIZE(mpls_table);
        struct ctl_table *table;
        int i;
 
@@ -2689,11 +2689,11 @@ static int mpls_net_init(struct net *net)
        /* Table data contains only offsets relative to the base of
         * the mdev at this point, so make them absolute.
         */
-       for (i = 0; i < ARRAY_SIZE(mpls_table) - 1; i++)
+       for (i = 0; i < tabel_size; i++)
                table[i].data = (char *)net + (uintptr_t)table[i].data;
 
        net->mpls.ctl = register_net_sysctl_sz(net, "net/mpls", table,
-                                              ARRAY_SIZE(mpls_table));
+                                              tabel_size);
        if (net->mpls.ctl == NULL) {
                kfree(table);
                return -ENOMEM;
diff --git a/net/unix/sysctl_net_unix.c b/net/unix/sysctl_net_unix.c
index 3e84b31c355a..ae45d4cfac39 100644
--- a/net/unix/sysctl_net_unix.c
+++ b/net/unix/sysctl_net_unix.c
@@ -19,7 +19,6 @@ static struct ctl_table unix_table[] = {
                .mode           = 0644,
                .proc_handler   = proc_dointvec
        },
-       { }
 };
 
 int __net_init unix_sysctl_register(struct net *net)

-- 
2.43.0




<Prev in Thread] Current Thread [Next in Thread>