* [PATCH] net: update the usage of CHECKSUM_UNNECESSARY @ 2012-03-19 21:12 Yi Zou 2012-03-19 21:38 ` David Miller 2012-05-08 17:48 ` Michael S. Tsirkin 0 siblings, 2 replies; 7+ messages in thread From: Yi Zou @ 2012-03-19 21:12 UTC (permalink / raw) To: netdev; +Cc: devel, bhutchings, jeffrey.t.kirsher As suggested by Ben, this adds the clarification on the usage of CHECKSUM_UNNECESSARY on the outgoing patch. Also add the usage description of NETIF_F_FCOE_CRC and CHECKSUM_UNNECESSARY for the kernel FCoE protocol driver. This is a follow-up to the following: http://patchwork.ozlabs.org/patch/147315/ Signed-off-by: Yi Zou <yi.zou@intel.com> Cc: Ben Hutchings <bhutchings@solarflare.com> Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Cc: www.Open-FCoE.org <devel@open-fcoe.org> --- include/linux/skbuff.h | 7 +++++++ 1 files changed, 7 insertions(+), 0 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 8dc8257..a2b9953 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -94,6 +94,13 @@ * about CHECKSUM_UNNECESSARY. 8) * NETIF_F_IPV6_CSUM about as dumb as the last one but does IPv6 instead. * + * UNNECESSARY: device will do per protocol specific csum. Protocol drivers + * that do not want net to perform the checksum calculation should use + * this flag in their outgoing skbs. + * NETIF_F_FCOE_CRC this indicates the device can do FCoE FC CRC + * offload. Correspondingly, the FCoE protocol driver + * stack should use CHECKSUM_UNNECESSARY. + * * Any questions? No questions, good. --ANK */ ^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH] net: update the usage of CHECKSUM_UNNECESSARY 2012-03-19 21:12 [PATCH] net: update the usage of CHECKSUM_UNNECESSARY Yi Zou @ 2012-03-19 21:38 ` David Miller 2012-05-08 17:48 ` Michael S. Tsirkin 1 sibling, 0 replies; 7+ messages in thread From: David Miller @ 2012-03-19 21:38 UTC (permalink / raw) To: yi.zou; +Cc: netdev, devel, bhutchings, jeffrey.t.kirsher From: Yi Zou <yi.zou@intel.com> Date: Mon, 19 Mar 2012 14:12:41 -0700 > As suggested by Ben, this adds the clarification on the usage of > CHECKSUM_UNNECESSARY on the outgoing patch. Also add the usage > description of NETIF_F_FCOE_CRC and CHECKSUM_UNNECESSARY > for the kernel FCoE protocol driver. > > This is a follow-up to the following: > http://patchwork.ozlabs.org/patch/147315/ > > Signed-off-by: Yi Zou <yi.zou@intel.com> > Cc: Ben Hutchings <bhutchings@solarflare.com> > Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com> > Cc: www.Open-FCoE.org <devel@open-fcoe.org> Applied. ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] net: update the usage of CHECKSUM_UNNECESSARY 2012-03-19 21:12 [PATCH] net: update the usage of CHECKSUM_UNNECESSARY Yi Zou 2012-03-19 21:38 ` David Miller @ 2012-05-08 17:48 ` Michael S. Tsirkin [not found] ` <20120508174831.GA27406-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> 1 sibling, 1 reply; 7+ messages in thread From: Michael S. Tsirkin @ 2012-05-08 17:48 UTC (permalink / raw) To: Yi Zou; +Cc: netdev, devel, bhutchings, jeffrey.t.kirsher On Mon, Mar 19, 2012 at 02:12:41PM -0700, Yi Zou wrote: > As suggested by Ben, this adds the clarification on the usage of > CHECKSUM_UNNECESSARY on the outgoing patch. Also add the usage > description of NETIF_F_FCOE_CRC and CHECKSUM_UNNECESSARY > for the kernel FCoE protocol driver. > > This is a follow-up to the following: > http://patchwork.ozlabs.org/patch/147315/ > > Signed-off-by: Yi Zou <yi.zou@intel.com> > Cc: Ben Hutchings <bhutchings@solarflare.com> > Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com> > Cc: www.Open-FCoE.org <devel@open-fcoe.org> > --- > > include/linux/skbuff.h | 7 +++++++ > 1 files changed, 7 insertions(+), 0 deletions(-) > > diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h > index 8dc8257..a2b9953 100644 > --- a/include/linux/skbuff.h > +++ b/include/linux/skbuff.h > @@ -94,6 +94,13 @@ > * about CHECKSUM_UNNECESSARY. 8) > * NETIF_F_IPV6_CSUM about as dumb as the last one but does IPv6 instead. > * > + * UNNECESSARY: device will do per protocol specific csum. Protocol drivers > + * that do not want net to perform the checksum calculation should use > + * this flag in their outgoing skbs. > + * NETIF_F_FCOE_CRC this indicates the device can do FCoE FC CRC > + * offload. Correspondingly, the FCoE protocol driver > + * stack should use CHECKSUM_UNNECESSARY. > + * > * Any questions? No questions, good. --ANK > */ > So just to make sure I understand, you never get UNNECESSARY packets on tx unless you declared NETIF_F_FCOE_CRC? Maybe the comment says this somehow but could not figure it out. > > -- > 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 ^ permalink raw reply [flat|nested] 7+ messages in thread
[parent not found: <20120508174831.GA27406-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>]
* Re: [PATCH] net: update the usage of CHECKSUM_UNNECESSARY [not found] ` <20120508174831.GA27406-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> @ 2012-05-08 18:20 ` Ben Hutchings 2012-05-09 6:03 ` Michael S. Tsirkin 0 siblings, 1 reply; 7+ messages in thread From: Ben Hutchings @ 2012-05-08 18:20 UTC (permalink / raw) To: Michael S. Tsirkin Cc: netdev-u79uwXL29TY76Z2rM5mHXA, jeffrey.t.kirsher-ral2JQCrhuEAvxtiuMwx3w, devel-s9riP+hp16TNLxjTenLetw On Tue, 2012-05-08 at 20:48 +0300, Michael S. Tsirkin wrote: > On Mon, Mar 19, 2012 at 02:12:41PM -0700, Yi Zou wrote: > > As suggested by Ben, this adds the clarification on the usage of > > CHECKSUM_UNNECESSARY on the outgoing patch. Also add the usage > > description of NETIF_F_FCOE_CRC and CHECKSUM_UNNECESSARY > > for the kernel FCoE protocol driver. > > > > This is a follow-up to the following: > > http://patchwork.ozlabs.org/patch/147315/ > > > > Signed-off-by: Yi Zou <yi.zou-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> > > Cc: Ben Hutchings <bhutchings-s/n/eUQHGBpZroRs9YW3xA@public.gmane.org> > > Cc: Jeff Kirsher <jeffrey.t.kirsher-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> > > Cc: www.Open-FCoE.org <devel-s9riP+hp16TNLxjTenLetw@public.gmane.org> > > --- > > > > include/linux/skbuff.h | 7 +++++++ > > 1 files changed, 7 insertions(+), 0 deletions(-) > > > > diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h > > index 8dc8257..a2b9953 100644 > > --- a/include/linux/skbuff.h > > +++ b/include/linux/skbuff.h > > @@ -94,6 +94,13 @@ > > * about CHECKSUM_UNNECESSARY. 8) > > * NETIF_F_IPV6_CSUM about as dumb as the last one but does IPv6 instead. > > * > > + * UNNECESSARY: device will do per protocol specific csum. Protocol drivers > > + * that do not want net to perform the checksum calculation should use > > + * this flag in their outgoing skbs. > > + * NETIF_F_FCOE_CRC this indicates the device can do FCoE FC CRC > > + * offload. Correspondingly, the FCoE protocol driver > > + * stack should use CHECKSUM_UNNECESSARY. > > + * > > * Any questions? No questions, good. --ANK > > */ > > > > So just to make sure I understand, you never get > UNNECESSARY packets on tx unless you declared NETIF_F_FCOE_CRC? > > Maybe the comment says this somehow but could not figure it out. That's what should happen now. In future CHECKSUM_UNNECESSARY could be used on output by other protocols which don't use TCP/IP-style checksums, but always dependent on the output device supporting the relevant offload feature. Ben. -- Ben Hutchings, Staff Engineer, Solarflare Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked. ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] net: update the usage of CHECKSUM_UNNECESSARY 2012-05-08 18:20 ` Ben Hutchings @ 2012-05-09 6:03 ` Michael S. Tsirkin 2012-05-10 0:05 ` Ben Hutchings 0 siblings, 1 reply; 7+ messages in thread From: Michael S. Tsirkin @ 2012-05-09 6:03 UTC (permalink / raw) To: Ben Hutchings; +Cc: Yi Zou, netdev, devel, jeffrey.t.kirsher On Tue, May 08, 2012 at 07:20:58PM +0100, Ben Hutchings wrote: > On Tue, 2012-05-08 at 20:48 +0300, Michael S. Tsirkin wrote: > > On Mon, Mar 19, 2012 at 02:12:41PM -0700, Yi Zou wrote: > > > As suggested by Ben, this adds the clarification on the usage of > > > CHECKSUM_UNNECESSARY on the outgoing patch. Also add the usage > > > description of NETIF_F_FCOE_CRC and CHECKSUM_UNNECESSARY > > > for the kernel FCoE protocol driver. > > > > > > This is a follow-up to the following: > > > http://patchwork.ozlabs.org/patch/147315/ > > > > > > Signed-off-by: Yi Zou <yi.zou@intel.com> > > > Cc: Ben Hutchings <bhutchings@solarflare.com> > > > Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com> > > > Cc: www.Open-FCoE.org <devel@open-fcoe.org> > > > --- > > > > > > include/linux/skbuff.h | 7 +++++++ > > > 1 files changed, 7 insertions(+), 0 deletions(-) > > > > > > diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h > > > index 8dc8257..a2b9953 100644 > > > --- a/include/linux/skbuff.h > > > +++ b/include/linux/skbuff.h > > > @@ -94,6 +94,13 @@ > > > * about CHECKSUM_UNNECESSARY. 8) > > > * NETIF_F_IPV6_CSUM about as dumb as the last one but does IPv6 instead. > > > * > > > + * UNNECESSARY: device will do per protocol specific csum. Protocol drivers > > > + * that do not want net to perform the checksum calculation should use > > > + * this flag in their outgoing skbs. > > > + * NETIF_F_FCOE_CRC this indicates the device can do FCoE FC CRC > > > + * offload. Correspondingly, the FCoE protocol driver > > > + * stack should use CHECKSUM_UNNECESSARY. > > > + * > > > * Any questions? No questions, good. --ANK > > > */ > > > > > > > So just to make sure I understand, you never get > > UNNECESSARY packets on tx unless you declared NETIF_F_FCOE_CRC? > > > > Maybe the comment says this somehow but could not figure it out. > > That's what should happen now. In future CHECKSUM_UNNECESSARY could be > used on output by other protocols which don't use TCP/IP-style > checksums, but always dependent on the output device supporting the > relevant offload feature. > > Ben. Isn't there another case: a device passes UNNECESSARY in on rx, and the skb is forwarded to another device? For example it is handled this way by tun, giving a nice performance boost for VMs, see 10a8d94a95742bb15b4e617ee9884bb4381362be > -- > Ben Hutchings, Staff Engineer, Solarflare > Not speaking for my employer; that's the marketing department's job. > They asked us to note that Solarflare product names are trademarked. ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] net: update the usage of CHECKSUM_UNNECESSARY 2012-05-09 6:03 ` Michael S. Tsirkin @ 2012-05-10 0:05 ` Ben Hutchings 2012-05-10 6:00 ` Michael S. Tsirkin 0 siblings, 1 reply; 7+ messages in thread From: Ben Hutchings @ 2012-05-10 0:05 UTC (permalink / raw) To: Michael S. Tsirkin, David Miller; +Cc: Yi Zou, netdev, devel, jeffrey.t.kirsher On Wed, 2012-05-09 at 09:03 +0300, Michael S. Tsirkin wrote: > On Tue, May 08, 2012 at 07:20:58PM +0100, Ben Hutchings wrote: > > On Tue, 2012-05-08 at 20:48 +0300, Michael S. Tsirkin wrote: > > > On Mon, Mar 19, 2012 at 02:12:41PM -0700, Yi Zou wrote: > > > > As suggested by Ben, this adds the clarification on the usage of > > > > CHECKSUM_UNNECESSARY on the outgoing patch. Also add the usage > > > > description of NETIF_F_FCOE_CRC and CHECKSUM_UNNECESSARY > > > > for the kernel FCoE protocol driver. > > > > > > > > This is a follow-up to the following: > > > > http://patchwork.ozlabs.org/patch/147315/ > > > > > > > > Signed-off-by: Yi Zou <yi.zou@intel.com> > > > > Cc: Ben Hutchings <bhutchings@solarflare.com> > > > > Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com> > > > > Cc: www.Open-FCoE.org <devel@open-fcoe.org> > > > > --- > > > > > > > > include/linux/skbuff.h | 7 +++++++ > > > > 1 files changed, 7 insertions(+), 0 deletions(-) > > > > > > > > diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h > > > > index 8dc8257..a2b9953 100644 > > > > --- a/include/linux/skbuff.h > > > > +++ b/include/linux/skbuff.h > > > > @@ -94,6 +94,13 @@ > > > > * about CHECKSUM_UNNECESSARY. 8) > > > > * NETIF_F_IPV6_CSUM about as dumb as the last one but does IPv6 instead. > > > > * > > > > + * UNNECESSARY: device will do per protocol specific csum. Protocol drivers > > > > + * that do not want net to perform the checksum calculation should use > > > > + * this flag in their outgoing skbs. > > > > + * NETIF_F_FCOE_CRC this indicates the device can do FCoE FC CRC > > > > + * offload. Correspondingly, the FCoE protocol driver > > > > + * stack should use CHECKSUM_UNNECESSARY. > > > > + * > > > > * Any questions? No questions, good. --ANK > > > > */ > > > > > > > > > > So just to make sure I understand, you never get > > > UNNECESSARY packets on tx unless you declared NETIF_F_FCOE_CRC? > > > > > > Maybe the comment says this somehow but could not figure it out. > > > > That's what should happen now. In future CHECKSUM_UNNECESSARY could be > > used on output by other protocols which don't use TCP/IP-style > > checksums, but always dependent on the output device supporting the > > relevant offload feature. > > > > Ben. > > Isn't there another case: a device passes UNNECESSARY in on rx, > and the skb is forwarded to another device? > For example it is handled this way by tun, giving a nice > performance boost for VMs, see 10a8d94a95742bb15b4e617ee9884bb4381362be Hmm... I thought UNNECESSARY was supposed to be replaced by NONE on output, but I don't see where that would happen. Which would mean we had an undocumented case here, and now we have ambiguity. :-( Ben. -- Ben Hutchings, Staff Engineer, Solarflare Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked. ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] net: update the usage of CHECKSUM_UNNECESSARY 2012-05-10 0:05 ` Ben Hutchings @ 2012-05-10 6:00 ` Michael S. Tsirkin 0 siblings, 0 replies; 7+ messages in thread From: Michael S. Tsirkin @ 2012-05-10 6:00 UTC (permalink / raw) To: Ben Hutchings; +Cc: David Miller, Yi Zou, netdev, devel, jeffrey.t.kirsher On Thu, May 10, 2012 at 01:05:01AM +0100, Ben Hutchings wrote: > On Wed, 2012-05-09 at 09:03 +0300, Michael S. Tsirkin wrote: > > On Tue, May 08, 2012 at 07:20:58PM +0100, Ben Hutchings wrote: > > > On Tue, 2012-05-08 at 20:48 +0300, Michael S. Tsirkin wrote: > > > > On Mon, Mar 19, 2012 at 02:12:41PM -0700, Yi Zou wrote: > > > > > As suggested by Ben, this adds the clarification on the usage of > > > > > CHECKSUM_UNNECESSARY on the outgoing patch. Also add the usage > > > > > description of NETIF_F_FCOE_CRC and CHECKSUM_UNNECESSARY > > > > > for the kernel FCoE protocol driver. > > > > > > > > > > This is a follow-up to the following: > > > > > http://patchwork.ozlabs.org/patch/147315/ > > > > > > > > > > Signed-off-by: Yi Zou <yi.zou@intel.com> > > > > > Cc: Ben Hutchings <bhutchings@solarflare.com> > > > > > Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com> > > > > > Cc: www.Open-FCoE.org <devel@open-fcoe.org> > > > > > --- > > > > > > > > > > include/linux/skbuff.h | 7 +++++++ > > > > > 1 files changed, 7 insertions(+), 0 deletions(-) > > > > > > > > > > diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h > > > > > index 8dc8257..a2b9953 100644 > > > > > --- a/include/linux/skbuff.h > > > > > +++ b/include/linux/skbuff.h > > > > > @@ -94,6 +94,13 @@ > > > > > * about CHECKSUM_UNNECESSARY. 8) > > > > > * NETIF_F_IPV6_CSUM about as dumb as the last one but does IPv6 instead. > > > > > * > > > > > + * UNNECESSARY: device will do per protocol specific csum. Protocol drivers > > > > > + * that do not want net to perform the checksum calculation should use > > > > > + * this flag in their outgoing skbs. > > > > > + * NETIF_F_FCOE_CRC this indicates the device can do FCoE FC CRC > > > > > + * offload. Correspondingly, the FCoE protocol driver > > > > > + * stack should use CHECKSUM_UNNECESSARY. > > > > > + * > > > > > * Any questions? No questions, good. --ANK > > > > > */ > > > > > > > > > > > > > So just to make sure I understand, you never get > > > > UNNECESSARY packets on tx unless you declared NETIF_F_FCOE_CRC? > > > > > > > > Maybe the comment says this somehow but could not figure it out. > > > > > > That's what should happen now. In future CHECKSUM_UNNECESSARY could be > > > used on output by other protocols which don't use TCP/IP-style > > > checksums, but always dependent on the output device supporting the > > > relevant offload feature. > > > > > > Ben. > > > > Isn't there another case: a device passes UNNECESSARY in on rx, > > and the skb is forwarded to another device? > > For example it is handled this way by tun, giving a nice > > performance boost for VMs, see 10a8d94a95742bb15b4e617ee9884bb4381362be > > Hmm... I thought UNNECESSARY was supposed to be replaced by NONE on > output, but I don't see where that would happen. Which would mean we > had an undocumented case here, and now we have ambiguity. :-( > > Ben. Ambiguity with FCoE? Why doesn't that use PARTIAL btw? Simply to avoid teaching net core about that protocol and NETIF_F_FCOE_CRC? > -- > Ben Hutchings, Staff Engineer, Solarflare > Not speaking for my employer; that's the marketing department's job. > They asked us to note that Solarflare product names are trademarked. ^ permalink raw reply [flat|nested] 7+ messages in thread
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Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
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2012-03-19 21:12 [PATCH] net: update the usage of CHECKSUM_UNNECESSARY Yi Zou
2012-03-19 21:38 ` David Miller
2012-05-08 17:48 ` Michael S. Tsirkin
[not found] ` <20120508174831.GA27406-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2012-05-08 18:20 ` Ben Hutchings
2012-05-09 6:03 ` Michael S. Tsirkin
2012-05-10 0:05 ` Ben Hutchings
2012-05-10 6:00 ` Michael S. Tsirkin
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