[PATCH v5 5/7] proc: Reduce cache miss in xfrm_statistics_seq_show

From: Jia He
Date: Wed Sep 28 2016 - 02:24:38 EST


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.

Signed-off-by: Jia He <hejianet@xxxxxxxxx>
---
net/xfrm/xfrm_proc.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/net/xfrm/xfrm_proc.c b/net/xfrm/xfrm_proc.c
index 9c4fbd8..dc0cea6 100644
--- a/net/xfrm/xfrm_proc.c
+++ b/net/xfrm/xfrm_proc.c
@@ -50,12 +50,18 @@ static const struct snmp_mib xfrm_mib_list[] = {

static int xfrm_statistics_seq_show(struct seq_file *seq, void *v)
{
- struct net *net = seq->private;
int i;
+ struct net *net = seq->private;
+ unsigned long buff[LINUX_MIB_XFRMMAX];
+
+ memset(buff, 0, sizeof(unsigned long) * LINUX_MIB_XFRMMAX);
+
+ snmp_get_cpu_field_batch(buff, xfrm_mib_list,
+ net->mib.xfrm_statistics);
for (i = 0; xfrm_mib_list[i].name; i++)
seq_printf(seq, "%-24s\t%lu\n", xfrm_mib_list[i].name,
- snmp_fold_field(net->mib.xfrm_statistics,
- xfrm_mib_list[i].entry));
+ buff[i]);
+
return 0;
}

--
2.5.5