netlink: smaller nla_attr_minlen table
Subsystems (3)
PATCH 1/1 netlink: smaller nla_attr_minlen table
Length of a netlink attribute may be u16 but lengths of basic attributes are much smaller, so small we can save 16 bytes of .rodata and pocket change inside .text.
16-bit is worse on x86-64 than 8-bit because of operand size override prefix.
add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-19 (-19)
function old new delta
validate_nla 418 417 -1
nla_policy_len 66 64 -2
nla_attr_minlen 32 16 -16
Total: Before=154865051, After=154865032, chg -0.00%
---
lib/nlattr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
lib/nlattr.c +1 -1
@@ -14,7 +14,7 @@#include <linux/types.h> #include <net/netlink.h> -static const u16 nla_attr_minlen[NLA_TYPE_MAX +1 ] = { +static const u8 nla_attr_minlen[NLA_TYPE_MAX +1 ] = { [NLA_U8 ] =sizeof (u8), [NLA_U16 ] =sizeof (u16), [NLA_U32 ] =sizeof (u32),
From: Alexey Dobriyan <[email protected]>
Date: Sat, 19 Nov 2016 03:59:07 +0300
Quoted 5 lines
Length of a netlink attribute may be u16 but lengths of basic attributes are much smaller, so small we can save 16 bytes of .rodata and pocket change inside .text.
16-bit is worse on x86-64 than 8-bit because of operand size override prefix.
...
Quoted 1 line
Signed-off-by Alexey Dobriyan <[email protected]>
Applied to net-next.