dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

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 <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2008-10-08 14:18:04 -07:00 committed by David S. Miller
parent 9088c56095
commit 3c689b7320
3 changed files with 23 additions and 20 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
include/net/ip.h
View File

@ -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;

16
net/ipv4/inet_connection_sock.c
View File

@ -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);

23
net/ipv4/sysctl_net_ipv4.c
View File

@ -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,