Re: [PATCH] iproute2: use IFLA_TXQLEN when it is available

[Eric Dumazet <eric.dumazet@gmail.com>]

Le jeudi 12 mai 2011 à 05:28 +0200, Eric Dumazet a écrit :
> Le jeudi 12 mai 2011 à 10:47 +0800, Changli Gao a écrit :
> > Use IFLA_TXQLEN when it is available, to avoid additional system calls.
> > 
> > Signed-off-by: Changli Gao <xiaosuo@gmail.com>
> > ---
> >  ip/ipaddress.c |   12 ++++++++++--
> >  1 file changed, 10 insertions(+), 2 deletions(-)
> > diff --git a/ip/ipaddress.c b/ip/ipaddress.c
> > index a1f78b9..59afafd 100644
> > --- a/ip/ipaddress.c
> > +++ b/ip/ipaddress.c
> > @@ -285,8 +285,16 @@ int print_linkinfo(const struct sockaddr_nl *who,
> >  	if (tb[IFLA_OPERSTATE])
> >  		print_operstate(fp, *(__u8 *)RTA_DATA(tb[IFLA_OPERSTATE]));
> >  		
> > -	if (filter.showqueue)
> > -		print_queuelen(fp, (char*)RTA_DATA(tb[IFLA_IFNAME]));
> > +	if (filter.showqueue) {
> > +		if (tb[IFLA_TXQLEN]) {
> > +			__u32 txqlen = *(__u32 *)RTA_DATA(tb[IFLA_TXQLEN]);
> > +
> > +			if (txqlen)
> > +				fprintf(fp, "qlen %u", txqlen);
> > +		} else {
> > +			print_queuelen(fp, (char*)RTA_DATA(tb[IFLA_IFNAME]));
> > +		}
> > +	}
> >  
> >  	if (!filter.family || filter.family == AF_PACKET) {
> >  		SPRINT_BUF(b1);
> 
> Hmm, what iproute2 version do you use ???
> 
> commit 62a5e0668e2920b7f09896abd884753255712a46
> Author: Eric Dumazet <dada1@cosmosbay.com>
> Date:   Fri Oct 23 06:25:53 2009 +0200
> 
>     ip: Support IFLA_TXQLEN in ip link show command
>     
>     We currently use an expensive ioctl() to get device txqueuelen, while
>     rtnetlink gave it to us for free. This patch speeds up ip link operation
>     when many devices are registered.
> 
> 


Apparently my patch was somehow lost

http://patchwork.ozlabs.org/patch/36762/

Strange thing is it's in my git tree.

Stephen, any idea of what happened ?

Thanks

commit 62a5e0668e2920b7f09896abd884753255712a46
Author: Eric Dumazet <dada1@cosmosbay.com>
Date:   Fri Oct 23 06:25:53 2009 +0200

[PATCH iproute2] ip: Support IFLA_TXQLEN in ip link show command
    
We currently use an expensive ioctl() to get device txqueuelen, while
rtnetlink gave it to us for free. This patch speeds up ip link operation
when many devices are registered.

diff --git a/ip/ipaddress.c b/ip/ipaddress.c
index 267ecb3..cadc1a3 100644
--- a/ip/ipaddress.c
+++ b/ip/ipaddress.c
@@ -131,26 +131,31 @@ static void print_operstate(FILE *f, __u8 state)
 		fprintf(f, "state %s ", oper_states[state]);
 }
 
-static void print_queuelen(FILE *f, const char *name)
+static void print_queuelen(FILE *f, struct rtattr *tb[IFLA_MAX + 1])
 {
-	struct ifreq ifr;
-	int s;
-
-	s = socket(AF_INET, SOCK_STREAM, 0);
-	if (s < 0)
-		return;
-
-	memset(&ifr, 0, sizeof(ifr));
-	strcpy(ifr.ifr_name, name);
-	if (ioctl(s, SIOCGIFTXQLEN, &ifr) < 0) {
-		fprintf(f, "ioctl(SIOCGIFXQLEN) failed: %s\n", strerror(errno));
+	int qlen;
+
+	if (tb[IFLA_TXQLEN])
+		qlen = *(int *)RTA_DATA(tb[IFLA_TXQLEN]);
+	else {
+		struct ifreq ifr;
+		int s = socket(AF_INET, SOCK_STREAM, 0);
+
+		if (s < 0)
+			return;
+
+		memset(&ifr, 0, sizeof(ifr));
+		strcpy(ifr.ifr_name, (char *)RTA_DATA(tb[IFLA_IFNAME]));
+		if (ioctl(s, SIOCGIFTXQLEN, &ifr) < 0) {
+			fprintf(f, "ioctl(SIOCGIFXQLEN) failed: %s\n", strerror(errno));
+			close(s);
+			return;
+		}
 		close(s);
-		return;
+		qlen = ifr.ifr_qlen;
 	}
-	close(s);
-
-	if (ifr.ifr_qlen)
-		fprintf(f, "qlen %d", ifr.ifr_qlen);
+	if (qlen)
+		fprintf(f, "qlen %d", qlen);
 }
 
 static void print_linktype(FILE *fp, struct rtattr *tb)
@@ -253,7 +258,7 @@ int print_linkinfo(const struct sockaddr_nl *who,
 		print_operstate(fp, *(__u8 *)RTA_DATA(tb[IFLA_OPERSTATE]));
 		
 	if (filter.showqueue)
-		print_queuelen(fp, (char*)RTA_DATA(tb[IFLA_IFNAME]));
+		print_queuelen(fp, tb);
 
 	if (!filter.family || filter.family == AF_PACKET) {
 		SPRINT_BUF(b1);