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blackhole(4): disable for locally originated TCP/UDP packets
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Authored by glebius on Oct 28 2021, 10:37 PM.

Details

Summary

In most cases blackholing for locally originated packets is undesired,
leads to different kind of lags and delays. Provide sysctls to enforce
it, e.g. for debugging purposes.

Diff Detail

Repository
R10 FreeBSD src repository
Lint
Automatic diff as part of commit; lint not applicable.
Unit
Automatic diff as part of commit; unit tests not applicable.

Event Timeline

rrs added inline comments.
sys/netinet/tcp_input.c
146

A boolean should have two values "true" and "false". Yet you use this
V_blackhole =1 or V_blackhole = 2

I think you need to change it back to an int since its used with multiple values.

sys/netinet/tcp_input.c
146

My boolean is V_blackhole_local. The V_blackhole remains int as it was.

Does it make sense to add some text to the blackhole man-page? Once this is in the tree, I can add the corresponding change for SCTP...

sys/netinet/tcp_input.c
146

He uses V_blackhole_local only as a boolean variable. This variable is different from V_blackhole.

rrs added a reviewer: rrs.
rrs added inline comments.
sys/netinet/tcp_input.c
146

ahh I see.. got confused by the variables :)

This revision is now accepted and ready to land.Nov 3 2021, 7:53 PM