Re: [RFC PATCH v2 0/6] Reduce cache miss for snmp_fold_field

From: Marcelo Ricardo Leitner
Date: Tue Sep 06 2016 - 08:44:33 EST


On Tue, Sep 06, 2016 at 10:30:03AM +0800, Jia He wrote:
...
> v2:
> - 1/6 fix bug in udplite statistics.
> - 1/6 snmp_seq_show is split into 2 parts
>
> Jia He (6):
> proc: Reduce cache miss in {snmp,netstat}_seq_show
> proc: Reduce cache miss in snmp6_seq_show
> proc: Reduce cache miss in sctp_snmp_seq_show
> proc: Reduce cache miss in xfrm_statistics_seq_show
> ipv6: Remove useless parameter in __snmp6_fill_statsdev
> net: Suppress the "Comparison to NULL could be written" warning

Hi Jia,

Did you try to come up with a generic interface for this, like
snmp_fold_fields64() (note the fieldS) or snmp_fold_field64_batch() ?

Sounds like we have the same code in several places and seems they all
operate very similarly. They have a percpu table, an identified max, a
destination buffer..

If this is possible, this would reduce the possibility of hiccups in a
particular code.

Marcelo