Messages in this thread | | | From | David Laight <> | Subject | RE: [PATCH net-next 1/3] net: gre_demux: add skb drop reasons to gre_rcv() | Date | Wed, 16 Mar 2022 10:12:00 +0000 |
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From: Jakub Kicinski > Sent: 16 March 2022 04:56 > > On Tue, 15 Mar 2022 21:49:01 -0600 David Ahern wrote: > > >> ver = skb->data[1]&0x7f; > > >> - if (ver >= GREPROTO_MAX) > > >> + if (ver >= GREPROTO_MAX) { > > >> + reason = SKB_DROP_REASON_GRE_VERSION; > > > > > > TBH I'm still not sure what level of granularity we should be shooting > > > for with the reasons. I'd throw all unexpected header values into one > > > bucket, not go for a reason per field, per protocol. But as I'm said > > > I'm not sure myself, so we can keep what you have.. > > > > I have stated before I do not believe every single drop point in the > > kernel needs a unique reason code. This is overkill. The reason augments > > information we already have -- the IP from kfree_skb tracepoint. > > That's certainly true. I wonder if there is a systematic way of > approaching these additions that'd help us picking the points were > we add reasons less of a judgment call.
Is it worth considering splitting the 'reason' into two parts? Eg x << 16 | y One part being the overall reason - and probably a define. The other qualifying the actual failing test and probably just being a number.
Then you get an overall view of the fails (which might even be counted) while still being able to locate the actual failing test.
David
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