From: Marcelo <marcelo.leitner@gmail.com>
To: Jia He <hejianet@gmail.com>
Cc: netdev@vger.kernel.org, linux-sctp@vger.kernel.org,
linux-kernel@vger.kernel.org, davem@davemloft.net,
Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
James Morris <jmorris@namei.org>,
Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
Patrick McHardy <kaber@trash.net>,
Vlad Yasevich <vyasevich@gmail.com>,
Neil Horman <nhorman@tuxdriver.com>,
Steffen Klassert <steffen.klassert@secunet.com>,
Herbert Xu <herbert@gondor.apana.org.au>
Subject: Re: [RFC PATCH v3 2/7] proc: Reduce cache miss in {snmp,netstat}_seq_show
Date: Mon, 12 Sep 2016 15:57:52 -0300 [thread overview]
Message-ID: <20160912185752.GB17689@localhost.localdomain> (raw)
In-Reply-To: <1473402842-1987-3-git-send-email-hejianet@gmail.com>
On Fri, Sep 09, 2016 at 02:33:57PM +0800, Jia He wrote:
> This is to use the generic interface snmp_get_cpu_field{,64}_batch to
> aggregate the data by going through all the items of each cpu sequentially.
> Then snmp_seq_show and netstat_seq_show are split into 2 parts to avoid build
> warning "the frame size" larger than 1024 on s390.
Yeah about that, did you test it with stack overflow detection?
These arrays can be quite large.
One more below..
>
> Signed-off-by: Jia He <hejianet@gmail.com>
> ---
> net/ipv4/proc.c | 106 +++++++++++++++++++++++++++++++++++++++-----------------
> 1 file changed, 74 insertions(+), 32 deletions(-)
>
> diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c
> index 9f665b6..c6fc80e 100644
> --- a/net/ipv4/proc.c
> +++ b/net/ipv4/proc.c
> @@ -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]
> */
> @@ -378,13 +380,15 @@ 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;
> + u64 buff64[IPSTATS_MIB_MAX];
> struct net *net = seq->private;
>
> - seq_puts(seq, "Ip: Forwarding DefaultTTL");
> + 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);
>
> @@ -393,57 +397,77 @@ 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)
> +{
> + int i;
> + unsigned long buff[TCPUDP_MIB_MAX];
> + struct net *net = seq->private;
> +
> + 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);
> @@ -457,41 +481,59 @@ static const struct file_operations snmp_seq_fops = {
> .release = single_release_net,
> };
>
> -
> -
> /*
> * Output /proc/net/netstat
> */
> -static int netstat_seq_show(struct seq_file *seq, void *v)
> +static int netstat_seq_show_tcpext(struct seq_file *seq, void *v)
> {
> int i;
> + unsigned long buff[LINUX_MIB_MAX];
> struct net *net = seq->private;
>
> + memset(buff, 0, sizeof(unsigned long) * LINUX_MIB_MAX);
> +
> seq_puts(seq, "TcpExt:");
> for (i = 0; snmp4_net_list[i].name != NULL; i++)
> seq_printf(seq, " %s", snmp4_net_list[i].name);
>
> seq_puts(seq, "\nTcpExt:");
> + snmp_get_cpu_field_batch(buff, snmp4_net_list,
> + net->mib.net_statistics);
> for (i = 0; snmp4_net_list[i].name != NULL; i++)
> - seq_printf(seq, " %lu",
> - snmp_fold_field(net->mib.net_statistics,
> - snmp4_net_list[i].entry));
> + seq_printf(seq, " %lu", buff[i]);
> +
> + return 0;
> +}
> +
> +static int netstat_seq_show_ipext(struct seq_file *seq, void *v)
> +{
> + int i;
> + u64 buff64[IPSTATS_MIB_MAX];
> + struct net *net = seq->private;
>
> seq_puts(seq, "\nIpExt:");
> for (i = 0; snmp4_ipextstats_list[i].name != NULL; i++)
> seq_printf(seq, " %s", snmp4_ipextstats_list[i].name);
>
> seq_puts(seq, "\nIpExt:");
You're missing a memset() call here.
> + snmp_get_cpu_field64_batch(buff64, snmp4_ipextstats_list,
> + net->mib.ip_statistics,
> + offsetof(struct ipstats_mib, syncp));
> for (i = 0; snmp4_ipextstats_list[i].name != NULL; i++)
> - seq_printf(seq, " %llu",
> - snmp_fold_field64(net->mib.ip_statistics,
> - snmp4_ipextstats_list[i].entry,
> - offsetof(struct ipstats_mib, syncp)));
> + seq_printf(seq, " %llu", buff64[i]);
>
> seq_putc(seq, '\n');
> return 0;
> }
>
> +static int netstat_seq_show(struct seq_file *seq, void *v)
> +{
> + netstat_seq_show_tcpext(seq, v);
> + netstat_seq_show_ipext(seq, v);
> +
> + return 0;
> +}
> +
> static int netstat_seq_open(struct inode *inode, struct file *file)
> {
> return single_open_net(inode, file, netstat_seq_show);
> --
> 1.8.3.1
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-sctp" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
next prev parent reply other threads:[~2016-09-12 18:57 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-09 6:33 [RFC PATCH v3 0/7] Reduce cache miss for snmp_fold_field Jia He
2016-09-09 6:33 ` [RFC PATCH v3 1/7] net:snmp: Introduce generic batch interfaces for snmp_get_cpu_field{,64} Jia He
2016-09-09 6:33 ` [RFC PATCH v3 2/7] proc: Reduce cache miss in {snmp,netstat}_seq_show Jia He
2016-09-12 18:57 ` Marcelo [this message]
2016-09-14 3:10 ` hejianet
2016-09-14 5:58 ` hejianet
2016-09-14 11:55 ` Marcelo
2016-09-21 16:18 ` hejianet
2016-09-21 18:24 ` Marcelo
2016-09-22 5:38 ` hejianet
2016-09-09 6:33 ` [RFC PATCH v3 3/7] proc: Reduce cache miss in snmp6_seq_show Jia He
2016-09-12 19:05 ` Marcelo
2016-09-14 3:11 ` hejianet
2016-09-09 6:33 ` [RFC PATCH v3 4/7] proc: Reduce cache miss in sctp_snmp_seq_show Jia He
2016-09-09 6:34 ` [RFC PATCH v3 5/7] proc: Reduce cache miss in xfrm_statistics_seq_show Jia He
2016-09-09 6:34 ` [RFC PATCH v3 6/7] ipv6: Remove useless parameter in __snmp6_fill_statsdev Jia He
2016-09-09 6:34 ` [RFC PATCH v3 7/7] net: Suppress the "Comparison to NULL could be written" warning Jia He
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20160912185752.GB17689@localhost.localdomain \
--to=marcelo.leitner@gmail.com \
--cc=davem@davemloft.net \
--cc=hejianet@gmail.com \
--cc=herbert@gondor.apana.org.au \
--cc=jmorris@namei.org \
--cc=kaber@trash.net \
--cc=kuznet@ms2.inr.ac.ru \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-sctp@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=nhorman@tuxdriver.com \
--cc=steffen.klassert@secunet.com \
--cc=vyasevich@gmail.com \
--cc=yoshfuji@linux-ipv6.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox