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From: Robert Watson <rwatson@FreeBSD.org>
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To: Vijay Singh <vijju.singh@gmail.com>
Subject: Re: KVERIFY for non-debug invariants?
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On Wed, 5 Dec 2012, Vijay Singh wrote:

> All. KASSERT() is a really need way of expressing invariants when INVARIANTS 
> is defined. However for regular, non-INVARIANTS code folks have the typical 
> if() panic() combos, or private macros. Would a KVERIFY() that does this in 
> non-INVARIANTS code make sense?

I'd certainly be fine with something like this.  It might be worth posting to 
arch@ with a code example, as hackers@ has a subset of the potentially 
interested audience.  INVARIANTS has got a bit heavier-weight over the years 
-- the main thing I run into in higher-performance scenarios is its additional 
UMA debugging, which causes a global lock to be acquired during sanity checks. 
It might be worth our pondering adding a new configure option for particularly 
slow invariant tests -- e.g., INVARIANTS_SLOW ... or maybe just 
INVARIANTS_UMA.  However, that's a different issue.

(I sort of feel that things labeled "assert" should be something we can turn 
on in production... so maybe INVARIANTS/KASSERT mission-creep is the issue.)

Robert