Hello!
> For 2.4, it won't happen, except for packets from userspace being
> interrupted by bottom halves and timers,
Processes from userspace really overlap since 2.3.15.
> but this is changing: you can look into Alexey's crystal ball at
It is not necessary to look into magic crystals. 8)
- Hooks, executed in process context, i.e. all output, post-routing
etc. must be multithreaded.
- Hooks (and all the code), usually executed from net_bh (input, forwarding)
also must be multithreaded, but not softnet is reason for this.
Netfilter itself creates concurrency in all the paths, which
used to be executed in net_bh context, when it reinjects packets.
Essentially, softnet adds __nothing__ new to these rules, except for one thing:
concurency becomes common, rather than marginal phenomenon in all the paths.
Essentially, it is the main argument, why I do not jest when proposing
to add softnet before 2.4. All the complexity and all the bugs are already
in 2.3 and softnet only clarifies code and fixes bugs. 8)8)
Alexey
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