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From Tianwei <tianwei.sh...@gmail.com>
Subject Re: Is that a race condition bug?
Date Fri, 05 Feb 2010 03:12:04 GMT
On Fri, Feb 5, 2010 at 12:14 AM, Nick Kew <nick@webthing.com> wrote:

> On Thu, 4 Feb 2010 15:20:54 +0800
> Tianwei <tianwei.sheng@gmail.com> wrote:
>
> > besides, the following warning indicated that developer already have
> > been aware of the problem and tolerate it:
> > 1. comments in worker.c:
> >   a:
> >  896         requests_this_child--; /* FIXME: should be synchronized -
> aaron */
> >   b:
> >  632         /* TODO: requests_this_child should be synchronized - aaron
> */
> >  633         if (requests_this_child <= 0) {
> >  634             check_infinite_requests();
> >  635         }
>
> When evaluating a race condition, you should consider what the worst
> possible outcome is if two or more threads collide in a race.  If it's
> something that matters, then you have a bug that should be fixed.
>
> The precise number of requests served in the lifetime of a worker
> process is not exactly critical!
>
> Hi, Nick,
    You are right. But without application specific knowledge, it's hard for
tool maker to
evaluate if a bug is harmful or not. For this "requests_this_child" one, I
can also learn that it's not critical.
But for the waring in fdqueue.c, I am not sure because there are already
several race condition fixes in the bug database.
If anyone is very familiar with that part of code, can you help have a look
at my analysis?

Thanks.

Tianwei

> --
> Nick Kew
>



-- 
Sheng, Tianwei
Inst. of High Performance Computing
Dept. of Computer Sci. & Tech.
Tsinghua Univ.

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