Commit ce218712 authored by Joel Granados's avatar Joel Granados Committed by David S. Miller
Browse files

net: Remove the now superfluous sentinel elements from ctl_table array 

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@bombadil.infradead.org/

)

* 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 c899710f
  ("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: default avatarJoel Granados <j.granados@samsung.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent a17ef9e6

net/core/neighbour.c

+1 −4
Original line number Diff line number Diff line
@@ -3733,7 +3733,7 @@ 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"),
@@ -3784,7 +3784,6 @@ static struct neigh_sysctl_table { 
			.extra2		= SYSCTL_INT_MAX,

			.proc_handler	= proc_dointvec_minmax,

		},

		{},

	},

};
@@ -3812,8 +3811,6 @@ 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;

net/core/sysctl_net_core.c

+6 −7
Original line number Diff line number Diff line
@@ -661,7 +661,6 @@ static struct ctl_table net_core_table[] = { 
		.proc_handler	= proc_dointvec_minmax,

		.extra1		= SYSCTL_ZERO,

	},

	{ }

};



static struct ctl_table netns_core_table[] = {
@@ -698,7 +697,6 @@ 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)
@@ -716,20 +714,21 @@ __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)) {

		int i;

		tbl = kmemdup(tbl, sizeof(netns_core_table), GFP_KERNEL);

		if (tbl == NULL)

			goto err_dup;



		for (tmp = tbl; tmp->procname; tmp++)

			tmp->data += (char *)net - (char *)&init_net;

		for (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;

net/dccp/sysctl.c

+0 −2
Original line number Diff line number Diff line
@@ -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;

net/ieee802154/6lowpan/reassembly.c

+1 −5
Original line number Diff line number Diff line
@@ -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)
@@ -370,11 +368,9 @@ 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;

	table[0].extra1	= &ieee802154_lowpan->fqdir->low_thresh;

net/mpls/af_mpls.c

+6 −7
Original line number Diff line number Diff line
@@ -1377,13 +1377,13 @@ 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;
@@ -1395,7 +1395,7 @@ 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;
@@ -1403,8 +1403,7 @@ 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;
@@ -2653,11 +2652,11 @@ static const struct ctl_table mpls_table[] = { 
		.extra1		= SYSCTL_ONE,

		.extra2		= &ttl_max,

	},

	{ }

};



static int mpls_net_init(struct net *net)

{

	size_t table_size = ARRAY_SIZE(mpls_table);

	struct ctl_table *table;

	int i;
@@ -2673,11 +2672,11 @@ 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 < table_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));

					       table_size);

	if (net->mpls.ctl == NULL) {

		kfree(table);

		return -ENOMEM;