cvs commit: src/sys/netinet tcp_syncache.c

[Jeff Roberson]

On Thu, 9 Feb 2006, Gleb Smirnoff wrote:

> On Wed, Feb 08, 2006 at 11:32:58PM +0000, Qing Li wrote:
> Q> qingli      2006-02-08 23:32:58 UTC
> Q>
> Q>   FreeBSD src repository
> Q>
> Q>   Modified files:
> Q>     sys/netinet          tcp_syncache.c
> Q>   Log:
> Q>   Redo the previous fix by setting the UMA_ZONE_ZINIT bit in the syncache
> Q>   zone, eliminating the need to call bzero() after each syncache entry
> Q>   allocation.
>
> UMA_ZONE_ZINIT flag for uma_zcreate() sets zone zinit method to bzero. I
> suggested to use M_ZERO flag for uma_zalloc().

This is correct.  Unless every item is zeroed when it is freed or in an 
acceptable state for the next allocation you should pass M_ZERO in.

>
> I'm not sure this is correct, so I'm asking Jeff for clarification. AFAIU
> from uma(9) manpage the zinit method is called on the first allocation. But
> when an item is freed and is put to uma cache, next uma_zalloc() will just
> return it from cache. If there is a ctor method, it would be called on
> every allocation, but not zinit method.
>
> -- 
> Totus tuus, Glebius.
> GLEBIUS-RIPN GLEB-RIPE
>