proc: Reduce cache miss in snmp_seq_show

This is to use the generic interfaces snmp_get_cpu_field{,64}_batch to
aggregate the data by going through all the items of each cpu sequentially.
Then snmp_seq_show is split into 2 parts to avoid build warning "the frame
size" larger than 1024.

Signed-off-by: Jia He <hejianet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jia He 2016-09-30 11:28:59 +08:00 committed by David S. Miller
parent 6348ef2dbb
commit f22d5c4909

View File

@ -46,6 +46,8 @@
#include <net/sock.h>
#include <net/raw.h>
#define TCPUDP_MIB_MAX max_t(u32, UDP_MIB_MAX, TCP_MIB_MAX)
/*
* Report socket allocation statistics [mea@utu.fi]
*/
@ -379,13 +381,15 @@ static void icmp_put(struct seq_file *seq)
/*
* Called from the PROCfs module. This outputs /proc/net/snmp.
*/
static int snmp_seq_show(struct seq_file *seq, void *v)
static int snmp_seq_show_ipstats(struct seq_file *seq, void *v)
{
int i;
struct net *net = seq->private;
u64 buff64[IPSTATS_MIB_MAX];
int i;
memset(buff64, 0, IPSTATS_MIB_MAX * sizeof(u64));
seq_puts(seq, "Ip: Forwarding DefaultTTL");
for (i = 0; snmp4_ipstats_list[i].name != NULL; i++)
seq_printf(seq, " %s", snmp4_ipstats_list[i].name);
@ -394,57 +398,77 @@ static int snmp_seq_show(struct seq_file *seq, void *v)
net->ipv4.sysctl_ip_default_ttl);
BUILD_BUG_ON(offsetof(struct ipstats_mib, mibs) != 0);
snmp_get_cpu_field64_batch(buff64, snmp4_ipstats_list,
net->mib.ip_statistics,
offsetof(struct ipstats_mib, syncp));
for (i = 0; snmp4_ipstats_list[i].name != NULL; i++)
seq_printf(seq, " %llu",
snmp_fold_field64(net->mib.ip_statistics,
snmp4_ipstats_list[i].entry,
offsetof(struct ipstats_mib, syncp)));
seq_printf(seq, " %llu", buff64[i]);
icmp_put(seq); /* RFC 2011 compatibility */
icmpmsg_put(seq);
return 0;
}
static int snmp_seq_show_tcp_udp(struct seq_file *seq, void *v)
{
unsigned long buff[TCPUDP_MIB_MAX];
struct net *net = seq->private;
int i;
memset(buff, 0, TCPUDP_MIB_MAX * sizeof(unsigned long));
seq_puts(seq, "\nTcp:");
for (i = 0; snmp4_tcp_list[i].name != NULL; i++)
seq_printf(seq, " %s", snmp4_tcp_list[i].name);
seq_puts(seq, "\nTcp:");
snmp_get_cpu_field_batch(buff, snmp4_tcp_list,
net->mib.tcp_statistics);
for (i = 0; snmp4_tcp_list[i].name != NULL; i++) {
/* MaxConn field is signed, RFC 2012 */
if (snmp4_tcp_list[i].entry == TCP_MIB_MAXCONN)
seq_printf(seq, " %ld",
snmp_fold_field(net->mib.tcp_statistics,
snmp4_tcp_list[i].entry));
seq_printf(seq, " %ld", buff[i]);
else
seq_printf(seq, " %lu",
snmp_fold_field(net->mib.tcp_statistics,
snmp4_tcp_list[i].entry));
seq_printf(seq, " %lu", buff[i]);
}
memset(buff, 0, TCPUDP_MIB_MAX * sizeof(unsigned long));
snmp_get_cpu_field_batch(buff, snmp4_udp_list,
net->mib.udp_statistics);
seq_puts(seq, "\nUdp:");
for (i = 0; snmp4_udp_list[i].name != NULL; i++)
seq_printf(seq, " %s", snmp4_udp_list[i].name);
seq_puts(seq, "\nUdp:");
for (i = 0; snmp4_udp_list[i].name != NULL; i++)
seq_printf(seq, " %lu",
snmp_fold_field(net->mib.udp_statistics,
snmp4_udp_list[i].entry));
seq_printf(seq, " %lu", buff[i]);
memset(buff, 0, TCPUDP_MIB_MAX * sizeof(unsigned long));
/* the UDP and UDP-Lite MIBs are the same */
seq_puts(seq, "\nUdpLite:");
snmp_get_cpu_field_batch(buff, snmp4_udp_list,
net->mib.udplite_statistics);
for (i = 0; snmp4_udp_list[i].name != NULL; i++)
seq_printf(seq, " %s", snmp4_udp_list[i].name);
seq_puts(seq, "\nUdpLite:");
for (i = 0; snmp4_udp_list[i].name != NULL; i++)
seq_printf(seq, " %lu",
snmp_fold_field(net->mib.udplite_statistics,
snmp4_udp_list[i].entry));
seq_printf(seq, " %lu", buff[i]);
seq_putc(seq, '\n');
return 0;
}
static int snmp_seq_show(struct seq_file *seq, void *v)
{
snmp_seq_show_ipstats(seq, v);
icmp_put(seq); /* RFC 2011 compatibility */
icmpmsg_put(seq);
snmp_seq_show_tcp_udp(seq, v);
return 0;
}
static int snmp_seq_open(struct inode *inode, struct file *file)
{
return single_open_net(inode, file, snmp_seq_show);