| Message ID | 1430263429-4069-3-git-send-email-edumazet@google.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
On Tue, Apr 28, 2015 at 7:23 PM, Eric Dumazet <edumazet@google.com> wrote: > Some Congestion Control modules can provide per flow information, > but current way to get this information is to use netlink. > > Like TCP_INFO, let's add TCP_CC_INFO so that applications can > issue a getsockopt() if they have a socket file descriptor, > instead of playing complex netlink games. > > Sample usage would be : > > union tcp_cc_info info; > socklen_t len = sizeof(info); > > if (getsockopt(fd, SOL_TCP, TCP_CC_INFO, &info, &len) == -1) > > Signed-off-by: Eric Dumazet <edumazet@google.com> > Cc: Yuchung Cheng <ycheng@google.com> > Cc: Neal Cardwell <ncardwell@google.com> > --- Acked-by: Neal Cardwell <ncardwell@google.com> A very useful facility. Thanks for putting this together, Eric! neal -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 04/29/2015 01:23 AM, Eric Dumazet wrote: > Some Congestion Control modules can provide per flow information, > but current way to get this information is to use netlink. > > Like TCP_INFO, let's add TCP_CC_INFO so that applications can > issue a getsockopt() if they have a socket file descriptor, > instead of playing complex netlink games. > > Sample usage would be : > > union tcp_cc_info info; > socklen_t len = sizeof(info); > > if (getsockopt(fd, SOL_TCP, TCP_CC_INFO, &info, &len) == -1) > > Signed-off-by: Eric Dumazet <edumazet@google.com> > Cc: Yuchung Cheng <ycheng@google.com> > Cc: Neal Cardwell <ncardwell@google.com> Presuming other cc algorithms would in future also export internal information through this interface, would it make sense to put tcp_cc_info into a container structure so we don't miss out attr (vegas, dctcp, ...), like: struct tcp_cc_exp { u32 kind; union tcp_cc_info info; }; Otherwise looks good: Acked-by: Daniel Borkmann <daniel@iogearbox.net> -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, 2015-04-29 at 10:17 +0200, Daniel Borkmann wrote: > On 04/29/2015 01:23 AM, Eric Dumazet wrote: > > Some Congestion Control modules can provide per flow information, > > but current way to get this information is to use netlink. > > > > Like TCP_INFO, let's add TCP_CC_INFO so that applications can > > issue a getsockopt() if they have a socket file descriptor, > > instead of playing complex netlink games. > > > > Sample usage would be : > > > > union tcp_cc_info info; > > socklen_t len = sizeof(info); > > > > if (getsockopt(fd, SOL_TCP, TCP_CC_INFO, &info, &len) == -1) > > > > Signed-off-by: Eric Dumazet <edumazet@google.com> > > Cc: Yuchung Cheng <ycheng@google.com> > > Cc: Neal Cardwell <ncardwell@google.com> > > Presuming other cc algorithms would in future also export > internal information through this interface, would it make > sense to put tcp_cc_info into a container structure so we > don't miss out attr (vegas, dctcp, ...), like: > > struct tcp_cc_exp { > u32 kind; > union tcp_cc_info info; > }; > > Otherwise looks good: > > Acked-by: Daniel Borkmann <daniel@iogearbox.net> I thought of this, but I really believe this is not needed, as the application can already fetch CC name (if really its does not know yet) And I also wanted to get same layout for info provided by netlink and getsockopt() Thanks ! -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 04/29/2015 01:07 PM, Eric Dumazet wrote: > On Wed, 2015-04-29 at 10:17 +0200, Daniel Borkmann wrote: >> On 04/29/2015 01:23 AM, Eric Dumazet wrote: >>> Some Congestion Control modules can provide per flow information, >>> but current way to get this information is to use netlink. >>> >>> Like TCP_INFO, let's add TCP_CC_INFO so that applications can >>> issue a getsockopt() if they have a socket file descriptor, >>> instead of playing complex netlink games. >>> >>> Sample usage would be : >>> >>> union tcp_cc_info info; >>> socklen_t len = sizeof(info); >>> >>> if (getsockopt(fd, SOL_TCP, TCP_CC_INFO, &info, &len) == -1) >>> >>> Signed-off-by: Eric Dumazet <edumazet@google.com> >>> Cc: Yuchung Cheng <ycheng@google.com> >>> Cc: Neal Cardwell <ncardwell@google.com> >> >> Presuming other cc algorithms would in future also export >> internal information through this interface, would it make >> sense to put tcp_cc_info into a container structure so we >> don't miss out attr (vegas, dctcp, ...), like: >> >> struct tcp_cc_exp { >> u32 kind; >> union tcp_cc_info info; >> }; >> >> Otherwise looks good: >> >> Acked-by: Daniel Borkmann <daniel@iogearbox.net> > > I thought of this, but I really believe this is not needed, as the > application can already fetch CC name (if really its does not know yet) > > And I also wanted to get same layout for info provided by netlink and > getsockopt() Ok, I'm fine with that. Presumably, applications making use of this facility would most likely set the cc op themselves from the application, so they know exactly what to expect here. Or, might have fetched it via the cc name albeit a bit inconvenient, but not impossible. Thanks, Daniel -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, Apr 28, 2015 at 4:23 PM, Eric Dumazet <edumazet@google.com> wrote: > Some Congestion Control modules can provide per flow information, > but current way to get this information is to use netlink. > > Like TCP_INFO, let's add TCP_CC_INFO so that applications can > issue a getsockopt() if they have a socket file descriptor, > instead of playing complex netlink games. > > Sample usage would be : > > union tcp_cc_info info; > socklen_t len = sizeof(info); > > if (getsockopt(fd, SOL_TCP, TCP_CC_INFO, &info, &len) == -1) > > Signed-off-by: Eric Dumazet <edumazet@google.com> > Cc: Yuchung Cheng <ycheng@google.com> > Cc: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Nice extension! > --- > include/uapi/linux/tcp.h | 1 + > net/ipv4/tcp.c | 21 +++++++++++++++++++++ > 2 files changed, 22 insertions(+) > > diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h > index 3b9718328d8b..937ec387276f 100644 > --- a/include/uapi/linux/tcp.h > +++ b/include/uapi/linux/tcp.h > @@ -112,6 +112,7 @@ enum { > #define TCP_FASTOPEN 23 /* Enable FastOpen on listeners */ > #define TCP_TIMESTAMP 24 > #define TCP_NOTSENT_LOWAT 25 /* limit number of unsent bytes in write queue */ > +#define TCP_CC_INFO 26 /* Get Congestion Control (optional) info */ > > struct tcp_repair_opt { > __u32 opt_code; > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > index 8c5cd9efebbc..1e06c75a6837 100644 > --- a/net/ipv4/tcp.c > +++ b/net/ipv4/tcp.c > @@ -252,6 +252,7 @@ > #include <linux/types.h> > #include <linux/fcntl.h> > #include <linux/poll.h> > +#include <linux/inet_diag.h> > #include <linux/init.h> > #include <linux/fs.h> > #include <linux/skbuff.h> > @@ -2734,6 +2735,26 @@ static int do_tcp_getsockopt(struct sock *sk, int level, > return -EFAULT; > return 0; > } > + case TCP_CC_INFO: { > + const struct tcp_congestion_ops *ca_ops; > + union tcp_cc_info info; > + size_t sz = 0; > + int attr; > + > + if (get_user(len, optlen)) > + return -EFAULT; > + > + ca_ops = icsk->icsk_ca_ops; > + if (ca_ops && ca_ops->get_info) > + sz = ca_ops->get_info(sk, ~0U, &attr, &info); > + > + len = min_t(unsigned int, len, sz); > + if (put_user(len, optlen)) > + return -EFAULT; > + if (copy_to_user(optval, &info, len)) > + return -EFAULT; > + return 0; > + } > case TCP_QUICKACK: > val = !icsk->icsk_ack.pingpong; > break; > -- > 2.2.0.rc0.207.ga3a616c > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Eric Dumazet <edumazet@google.com> Date: Tue, 28 Apr 2015 16:23:49 -0700 > Some Congestion Control modules can provide per flow information, > but current way to get this information is to use netlink. > > Like TCP_INFO, let's add TCP_CC_INFO so that applications can > issue a getsockopt() if they have a socket file descriptor, > instead of playing complex netlink games. > > Sample usage would be : > > union tcp_cc_info info; > socklen_t len = sizeof(info); > > if (getsockopt(fd, SOL_TCP, TCP_CC_INFO, &info, &len) == -1) > > Signed-off-by: Eric Dumazet <edumazet@google.com> Applied. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h index 3b9718328d8b..937ec387276f 100644 --- a/include/uapi/linux/tcp.h +++ b/include/uapi/linux/tcp.h @@ -112,6 +112,7 @@ enum { #define TCP_FASTOPEN 23 /* Enable FastOpen on listeners */ #define TCP_TIMESTAMP 24 #define TCP_NOTSENT_LOWAT 25 /* limit number of unsent bytes in write queue */ +#define TCP_CC_INFO 26 /* Get Congestion Control (optional) info */ struct tcp_repair_opt { __u32 opt_code; diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 8c5cd9efebbc..1e06c75a6837 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -252,6 +252,7 @@ #include <linux/types.h> #include <linux/fcntl.h> #include <linux/poll.h> +#include <linux/inet_diag.h> #include <linux/init.h> #include <linux/fs.h> #include <linux/skbuff.h> @@ -2734,6 +2735,26 @@ static int do_tcp_getsockopt(struct sock *sk, int level, return -EFAULT; return 0; } + case TCP_CC_INFO: { + const struct tcp_congestion_ops *ca_ops; + union tcp_cc_info info; + size_t sz = 0; + int attr; + + if (get_user(len, optlen)) + return -EFAULT; + + ca_ops = icsk->icsk_ca_ops; + if (ca_ops && ca_ops->get_info) + sz = ca_ops->get_info(sk, ~0U, &attr, &info); + + len = min_t(unsigned int, len, sz); + if (put_user(len, optlen)) + return -EFAULT; + if (copy_to_user(optval, &info, len)) + return -EFAULT; + return 0; + } case TCP_QUICKACK: val = !icsk->icsk_ack.pingpong; break;
Some Congestion Control modules can provide per flow information, but current way to get this information is to use netlink. Like TCP_INFO, let's add TCP_CC_INFO so that applications can issue a getsockopt() if they have a socket file descriptor, instead of playing complex netlink games. Sample usage would be : union tcp_cc_info info; socklen_t len = sizeof(info); if (getsockopt(fd, SOL_TCP, TCP_CC_INFO, &info, &len) == -1) Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> --- include/uapi/linux/tcp.h | 1 + net/ipv4/tcp.c | 21 +++++++++++++++++++++ 2 files changed, 22 insertions(+)