Commit e5086736 authored by Jakub Kicinski's avatar Jakub Kicinski Committed by David S. Miller
Browse files

genetlink: reorg struct genl_family 



There are holes and oversized members in struct genl_family.

Before: /* size: 104, cachelines: 2, members: 16 */
After:  /* size:  88, cachelines: 2, members: 16 */

The command field in struct genlmsghdr is a u8, so no point
in the operation count being 32 bit. Also operation 0 is
usually undefined, so we only need 255 entries.

netnsok and parallel_ops are only ever initialized to true.

We can grow the fields as needed, compiler should warn us
if someone tries to assign larger constants.

Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
Reviewed-by: default avatarJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5a38b4fc

include/net/genetlink.h

+5 −5
Original line number Diff line number Diff line
@@ -48,8 +48,11 @@ struct genl_family { 
	char			name[GENL_NAMSIZ];

	unsigned int		version;

	unsigned int		maxattr;

	bool			netnsok;

	bool			parallel_ops;

	unsigned int		mcgrp_offset;	/* private */

	u8			netnsok:1;

	u8			parallel_ops:1;

	u8			n_ops;

	u8			n_mcgrps;

	const struct nla_policy *policy;

	int			(*pre_doit)(const struct genl_ops *ops,

					    struct sk_buff *skb,
@@ -59,9 +62,6 @@ struct genl_family { 
					     struct genl_info *info);

	const struct genl_ops *	ops;

	const struct genl_multicast_group *mcgrps;

	unsigned int		n_ops;

	unsigned int		n_mcgrps;

	unsigned int		mcgrp_offset;	/* private */

	struct module		*module;

};