From 3c689b7320ae6f20dba6a8b71806a6c6fd604ee8 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 8 Oct 2008 14:18:04 -0700 Subject: [PATCH] inet: cleanup of local_port_range I noticed sysctl_local_port_range[] and its associated seqlock sysctl_local_port_range_lock were on separate cache lines. Moreover, sysctl_local_port_range[] was close to unrelated variables, highly modified, leading to cache misses. Moving these two variables in a structure can help data locality and moving this structure to read_mostly section helps sharing of this data among cpus. Cleanup of extern declarations (moved in include file where they belong), and use of inet_get_local_port_range() accessor instead of direct access to ports values. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/net/ip.h | 4 ++++ net/ipv4/inet_connection_sock.c | 16 +++++++++------- net/ipv4/sysctl_net_ipv4.c | 23 ++++++++++------------- 3 files changed, 23 insertions(+), 20 deletions(-) diff --git a/include/net/ip.h b/include/net/ip.h index d678ea3d474..1cbccaf0de3 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -178,6 +178,10 @@ extern unsigned long snmp_fold_field(void *mib[], int offt); extern int snmp_mib_init(void *ptr[2], size_t mibsize); extern void snmp_mib_free(void *ptr[2]); +extern struct local_ports { + seqlock_t lock; + int range[2]; +} sysctl_local_ports; extern void inet_get_local_port_range(int *low, int *high); extern int sysctl_ip_default_ttl; diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c index 21fcc5a9045..bd1278a2d82 100644 --- a/net/ipv4/inet_connection_sock.c +++ b/net/ipv4/inet_connection_sock.c @@ -30,20 +30,22 @@ EXPORT_SYMBOL(inet_csk_timer_bug_msg); #endif /* - * This array holds the first and last local port number. + * This struct holds the first and last local port number. */ -int sysctl_local_port_range[2] = { 32768, 61000 }; -DEFINE_SEQLOCK(sysctl_port_range_lock); +struct local_ports sysctl_local_ports __read_mostly = { + .lock = SEQLOCK_UNLOCKED, + .range = { 32768, 61000 }, +}; void inet_get_local_port_range(int *low, int *high) { unsigned seq; do { - seq = read_seqbegin(&sysctl_port_range_lock); + seq = read_seqbegin(&sysctl_local_ports.lock); - *low = sysctl_local_port_range[0]; - *high = sysctl_local_port_range[1]; - } while (read_seqretry(&sysctl_port_range_lock, seq)); + *low = sysctl_local_ports.range[0]; + *high = sysctl_local_ports.range[1]; + } while (read_seqretry(&sysctl_local_ports.lock, seq)); } EXPORT_SYMBOL(inet_get_local_port_range); diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c index e0689fd7b79..276d047fb85 100644 --- a/net/ipv4/sysctl_net_ipv4.c +++ b/net/ipv4/sysctl_net_ipv4.c @@ -26,16 +26,13 @@ static int tcp_retr1_max = 255; static int ip_local_port_range_min[] = { 1, 1 }; static int ip_local_port_range_max[] = { 65535, 65535 }; -extern seqlock_t sysctl_port_range_lock; -extern int sysctl_local_port_range[2]; - /* Update system visible IP port range */ static void set_local_port_range(int range[2]) { - write_seqlock(&sysctl_port_range_lock); - sysctl_local_port_range[0] = range[0]; - sysctl_local_port_range[1] = range[1]; - write_sequnlock(&sysctl_port_range_lock); + write_seqlock(&sysctl_local_ports.lock); + sysctl_local_ports.range[0] = range[0]; + sysctl_local_ports.range[1] = range[1]; + write_sequnlock(&sysctl_local_ports.lock); } /* Validate changes from /proc interface. */ @@ -44,8 +41,7 @@ static int ipv4_local_port_range(ctl_table *table, int write, struct file *filp, size_t *lenp, loff_t *ppos) { int ret; - int range[2] = { sysctl_local_port_range[0], - sysctl_local_port_range[1] }; + int range[2]; ctl_table tmp = { .data = &range, .maxlen = sizeof(range), @@ -54,6 +50,7 @@ static int ipv4_local_port_range(ctl_table *table, int write, struct file *filp, .extra2 = &ip_local_port_range_max, }; + inet_get_local_port_range(range, range + 1); ret = proc_dointvec_minmax(&tmp, write, filp, buffer, lenp, ppos); if (write && ret == 0) { @@ -73,8 +70,7 @@ static int ipv4_sysctl_local_port_range(ctl_table *table, int __user *name, void __user *newval, size_t newlen) { int ret; - int range[2] = { sysctl_local_port_range[0], - sysctl_local_port_range[1] }; + int range[2]; ctl_table tmp = { .data = &range, .maxlen = sizeof(range), @@ -83,6 +79,7 @@ static int ipv4_sysctl_local_port_range(ctl_table *table, int __user *name, .extra2 = &ip_local_port_range_max, }; + inet_get_local_port_range(range, range + 1); ret = sysctl_intvec(&tmp, name, nlen, oldval, oldlenp, newval, newlen); if (ret == 0 && newval && newlen) { if (range[1] < range[0]) @@ -396,8 +393,8 @@ static struct ctl_table ipv4_table[] = { { .ctl_name = NET_IPV4_LOCAL_PORT_RANGE, .procname = "ip_local_port_range", - .data = &sysctl_local_port_range, - .maxlen = sizeof(sysctl_local_port_range), + .data = &sysctl_local_ports.range, + .maxlen = sizeof(sysctl_local_ports.range), .mode = 0644, .proc_handler = &ipv4_local_port_range, .strategy = &ipv4_sysctl_local_port_range, -- 2.41.0