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Date: Wed, 15 Dec 2004 07:56:53 -0800 (PST)
From: "Kamal R. Prasad" <kamalpr@yahoo.com>
To: Andrey Simonenko <simon@comsys.ntu-kpi.kiev.ua>
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cc: freebsd-hackers@freebsd.org
Subject: Re: FreeBSD system call implementation
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--- Andrey Simonenko <simon@comsys.ntu-kpi.kiev.ua>
wrote:

> On Wed, Dec 15, 2004 at 08:19:05PM +0530, Ravi
> Krishna wrote:
> 
> > My question is why we store the
> p->p_sysent->sv_table
> > for each process. What is the reason for keeping
> this per process?
> > Are there some situations where two processes can
> have different system calls
> > available?
> 
> Processes can have different p_sysent, because the
> kernel supports
> different ABIs.  sv_entry (pointer to some system
> call table) is

Sounds rather inefficient to have a per-process table
rather than a set of ABIs into which the per process
table is an indirection (similar to say vnops).

regards
-kamal



		
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