From ec733b15a3ef0b5759141a177f8044a2f40c41e7 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 18 Mar 2010 20:36:06 +0000 Subject: [PATCH] net: snmp mib cleanup There is no point to align or pad mibs to cache lines, they are per cpu allocated with a 8 bytes alignment anyway. This wastes space for no gain. This patch removes __SNMP_MIB_ALIGN__ Since SNMP mibs contain "unsigned long" fields only, we can relax the allocation alignment from "unsigned long long" to "unsigned long" Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/net/sctp/sctp.h | 2 +- include/net/snmp.h | 29 +++++++---------------------- net/dccp/dccp.h | 2 +- net/ipv4/af_inet.c | 4 ++-- 4 files changed, 11 insertions(+), 26 deletions(-) diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h index 78740ec57d5d..59151557406c 100644 --- a/include/net/sctp/sctp.h +++ b/include/net/sctp/sctp.h @@ -268,7 +268,7 @@ enum { #define SCTP_MIB_MAX __SCTP_MIB_MAX struct sctp_mib { unsigned long mibs[SCTP_MIB_MAX]; -} __SNMP_MIB_ALIGN__; +}; /* Print debugging messages. */ diff --git a/include/net/snmp.h b/include/net/snmp.h index 692ee0061dc4..884fdbb74b23 100644 --- a/include/net/snmp.h +++ b/include/net/snmp.h @@ -52,26 +52,11 @@ struct snmp_mib { * count on the 20Gb/s + networks people expect in a few years time! */ -/* - * The rule for padding: - * Best is power of two because then the right structure can be found by a - * simple shift. The structure should be always cache line aligned. - * gcc needs n=alignto(cachelinesize, popcnt(sizeof(bla_mib))) shift/add - * instructions to emulate multiply in case it is not power-of-two. - * Currently n is always <=3 for all sizes so simple cache line alignment - * is enough. - * - * The best solution would be a global CPU local area , especially on 64 - * and 128byte cacheline machine it makes a *lot* of sense -AK - */ - -#define __SNMP_MIB_ALIGN__ ____cacheline_aligned - /* IPstats */ #define IPSTATS_MIB_MAX __IPSTATS_MIB_MAX struct ipstats_mib { unsigned long mibs[IPSTATS_MIB_MAX]; -} __SNMP_MIB_ALIGN__; +}; /* ICMP */ #define ICMP_MIB_DUMMY __ICMP_MIB_MAX @@ -79,36 +64,36 @@ struct ipstats_mib { struct icmp_mib { unsigned long mibs[ICMP_MIB_MAX]; -} __SNMP_MIB_ALIGN__; +}; #define ICMPMSG_MIB_MAX __ICMPMSG_MIB_MAX struct icmpmsg_mib { unsigned long mibs[ICMPMSG_MIB_MAX]; -} __SNMP_MIB_ALIGN__; +}; /* ICMP6 (IPv6-ICMP) */ #define ICMP6_MIB_MAX __ICMP6_MIB_MAX struct icmpv6_mib { unsigned long mibs[ICMP6_MIB_MAX]; -} __SNMP_MIB_ALIGN__; +}; #define ICMP6MSG_MIB_MAX __ICMP6MSG_MIB_MAX struct icmpv6msg_mib { unsigned long mibs[ICMP6MSG_MIB_MAX]; -} __SNMP_MIB_ALIGN__; +}; /* TCP */ #define TCP_MIB_MAX __TCP_MIB_MAX struct tcp_mib { unsigned long mibs[TCP_MIB_MAX]; -} __SNMP_MIB_ALIGN__; +}; /* UDP */ #define UDP_MIB_MAX __UDP_MIB_MAX struct udp_mib { unsigned long mibs[UDP_MIB_MAX]; -} __SNMP_MIB_ALIGN__; +}; /* Linux */ #define LINUX_MIB_MAX __LINUX_MIB_MAX diff --git a/net/dccp/dccp.h b/net/dccp/dccp.h index 5ef32c2f0d6a..53f8e12d0c10 100644 --- a/net/dccp/dccp.h +++ b/net/dccp/dccp.h @@ -189,7 +189,7 @@ enum { #define DCCP_MIB_MAX __DCCP_MIB_MAX struct dccp_mib { unsigned long mibs[DCCP_MIB_MAX]; -} __SNMP_MIB_ALIGN__; +}; DECLARE_SNMP_STAT(struct dccp_mib, dccp_statistics); #define DCCP_INC_STATS(field) SNMP_INC_STATS(dccp_statistics, field) diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 33b7dffa7732..55e11906a73a 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1401,10 +1401,10 @@ EXPORT_SYMBOL_GPL(snmp_fold_field); int snmp_mib_init(void __percpu *ptr[2], size_t mibsize) { BUG_ON(ptr == NULL); - ptr[0] = __alloc_percpu(mibsize, __alignof__(unsigned long long)); + ptr[0] = __alloc_percpu(mibsize, __alignof__(unsigned long)); if (!ptr[0]) goto err0; - ptr[1] = __alloc_percpu(mibsize, __alignof__(unsigned long long)); + ptr[1] = __alloc_percpu(mibsize, __alignof__(unsigned long)); if (!ptr[1]) goto err1; return 0; -- 2.30.2