From owner-freebsd-current  Tue Jul  9 15: 0:29 2002
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Date: Tue, 9 Jul 2002 14:59:34 -0700 (PDT)
From: Julian Elischer <julian@elischer.org>
To: Bruce Evans <bde@zeta.org.au>
Cc: John Baldwin <jhb@FreeBSD.ORG>,
	FreeBSD current users <current@FreeBSD.ORG>,
	FreeBSD current users <current@FreeBSD.ORG>
Subject: RE: userret() , ast() and the end of syscalls
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On Wed, 10 Jul 2002, Bruce Evans wrote:

> Hopefully there won't be any unconditional code.  Unconditional code
> in userret() pessimizes all syscalls.  Unconditional code added by KSEIII
> pessimized basic syscall overhead by 10% according to lmbench2.

Mostly it's conditional..
	if (p->p_flag & P_KSES) 
in syscall()
and 
	if (p->p_flag & P_KSES) {
in userret()

it's probably  
        PROC_LOCK(p);
        thread_suspend_check(0);        /* Can suspend or kill */
        PROC_UNLOCK(p);


try replace it with:
        if (P_SHOULDSTOP(p) {
                PROC_LOCK(p);
                thread_suspend_check(0);        /* Can suspend or kill */
                PROC_UNLOCK(p);
        }

> 
> Bruce
> 
> 


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