svn commit: r281239 - head/sys/netinet

[Gleb Smirnoff]

On Tue, Apr 07, 2015 at 11:09:35PM +0000, Adrian Chadd wrote:
A> Author: adrian
A> Date: Tue Apr  7 23:09:34 2015
A> New Revision: 281239
A> URL: https://svnweb.freebsd.org/changeset/base/281239
A> 
A> Log:
A>   Move the IPv4 reassembly queue locking from a single lock to be per-bucket (global).
A>   
A>   This significantly improves performance on multi-core servers where there
A>   is any kind of IPv4 reassembly going on.
A>   
A>   glebius@ would like to see the locking moved to be attached to the reassembly
A>   bucket, which would make it per-bucket + per-VNET, instead of being global.
A>   I decided to keep it global for now as it's the minimal useful change;
A>   if people agree / wish to migrate it to be per-bucket / per-VNET then please
A>   do feel free to do so.  I won't complain.
A>   
A>   Thanks to Norse Corp for giving me access to much larger servers
A>   to test this at across the 4 core boxes I have at home.
A>   
A>   Differential Revision:	https://reviews.freebsd.org/D2095
A>   Reviewed by:	glebius (initial comments incorporated into this patch)

No, they are not.

Also, I just noticed another issue with the patch. You initialize the mutexes,
which are global, in the ip_init() which is called for every VNET. That would
lead to panic of initializing already initialized mutex. If you followed my advice,
that would not happen. Now VIMAGE+INVARIANTS is broken instantly, and w/o
INVARIANTS may panic if VIMAGE created under IP traffic.

My comment that purging from a bucket that is determined by source IP has
security implications was also ignored.

I will fix this all myself.

-- 
Totus tuus, Glebius.