[PATCH net] Documentation: fix sctp_wmem in ip-sysctl.rst

[PATCH net] Documentation: fix sctp_wmem in ip-sysctl.rst

[Xin Long]

Since commit 1033990ac5b2 ("sctp: implement memory accounting on tx path"),
SCTP has supported memory accounting on tx path where 'sctp_wmem' is used
by sk_wmem_schedule(). So we should fix the description for this option in
ip-sysctl.rst accordingly.

Fixes: 1033990ac5b2 ("sctp: implement memory accounting on tx path")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
---
 Documentation/networking/ip-sysctl.rst | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst
index 0e58001f8580..b7db2e5e5cc5 100644
--- a/Documentation/networking/ip-sysctl.rst
+++ b/Documentation/networking/ip-sysctl.rst
@@ -2870,7 +2870,14 @@ sctp_rmem - vector of 3 INTEGERs: min, default, max
 	Default: 4K
 
 sctp_wmem  - vector of 3 INTEGERs: min, default, max
-	Currently this tunable has no effect.
+	Only the first value ("min") is used, "default" and "max" are
+	ignored.
+
+	min: Minimal size of send buffer used by SCTP socket.
+	It is guaranteed to each SCTP socket (but not association) even
+	under moderate memory pressure.
+
+	Default: 4K
 
 addr_scope_policy - INTEGER
 	Control IPv4 address scoping - draft-stewart-tsvwg-sctp-ipv4-00
-- 
2.31.1

Re: [PATCH net] Documentation: fix sctp_wmem in ip-sysctl.rst

[Marcelo Ricardo Leitner]

On Mon, Jul 18, 2022 at 01:54:56PM -0400, Xin Long wrote:
> Since commit 1033990ac5b2 ("sctp: implement memory accounting on tx path"),
> SCTP has supported memory accounting on tx path where 'sctp_wmem' is used
> by sk_wmem_schedule(). So we should fix the description for this option in
> ip-sysctl.rst accordingly.
> 
> Fixes: 1033990ac5b2 ("sctp: implement memory accounting on tx path")
> Signed-off-by: Xin Long <lucien.xin@gmail.com>
> ---
>  Documentation/networking/ip-sysctl.rst | 9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst
> index 0e58001f8580..b7db2e5e5cc5 100644
> --- a/Documentation/networking/ip-sysctl.rst
> +++ b/Documentation/networking/ip-sysctl.rst
> @@ -2870,7 +2870,14 @@ sctp_rmem - vector of 3 INTEGERs: min, default, max
>  	Default: 4K
>  
>  sctp_wmem  - vector of 3 INTEGERs: min, default, max
> -	Currently this tunable has no effect.
> +	Only the first value ("min") is used, "default" and "max" are
> +	ignored.
> +
> +	min: Minimal size of send buffer used by SCTP socket.

I'm not a native English speaker, but this seems better:
"Minimum size of send buffer that can be used by an SCTP socket."

> +	It is guaranteed to each SCTP socket (but not association) even
> +	under moderate memory pressure.
> +
> +	Default: 4K
>  
>  addr_scope_policy - INTEGER
>  	Control IPv4 address scoping - draft-stewart-tsvwg-sctp-ipv4-00
> -- 
> 2.31.1
> 

Re: [PATCH net] Documentation: fix sctp_wmem in ip-sysctl.rst

[Xin Long]

On Tue, Jul 19, 2022 at 2:49 PM Marcelo Ricardo Leitner
<marcelo.leitner@gmail.com> wrote:
>
> On Mon, Jul 18, 2022 at 01:54:56PM -0400, Xin Long wrote:
> > Since commit 1033990ac5b2 ("sctp: implement memory accounting on tx path"),
> > SCTP has supported memory accounting on tx path where 'sctp_wmem' is used
> > by sk_wmem_schedule(). So we should fix the description for this option in
> > ip-sysctl.rst accordingly.
> >
> > Fixes: 1033990ac5b2 ("sctp: implement memory accounting on tx path")
> > Signed-off-by: Xin Long <lucien.xin@gmail.com>
> > ---
> >  Documentation/networking/ip-sysctl.rst | 9 ++++++++-
> >  1 file changed, 8 insertions(+), 1 deletion(-)
> >
> > diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst
> > index 0e58001f8580..b7db2e5e5cc5 100644
> > --- a/Documentation/networking/ip-sysctl.rst
> > +++ b/Documentation/networking/ip-sysctl.rst
> > @@ -2870,7 +2870,14 @@ sctp_rmem - vector of 3 INTEGERs: min, default, max
> >       Default: 4K
> >
> >  sctp_wmem  - vector of 3 INTEGERs: min, default, max
> > -     Currently this tunable has no effect.
> > +     Only the first value ("min") is used, "default" and "max" are
> > +     ignored.
> > +
> > +     min: Minimal size of send buffer used by SCTP socket.
>
> I'm not a native English speaker, but this seems better:
> "Minimum size of send buffer that can be used by an SCTP socket."
This is from "sctp_rmem" part:

"min: Minimal size of receive buffer used by SCTP socket."

I think it was copied from "tcp_rmem", and yes it should be "SCTP sockets"
or "an SCTP socket.", and "Minimum size" seems more common.

will post v2. Thanks.

>
> > +     It is guaranteed to each SCTP socket (but not association) even
> > +     under moderate memory pressure.
> > +
> > +     Default: 4K
> >
> >  addr_scope_policy - INTEGER
> >       Control IPv4 address scoping - draft-stewart-tsvwg-sctp-ipv4-00
> > --
> > 2.31.1
> >