In message <[EMAIL PROTECTED]>, Matt Dillon writes:
>:> * Stephen McKay <[EMAIL PROTECTED]> [000805 08:49] wrote:
>:> > 
>:> > Patch 2 is smaller and possibly controversial.  Normally bufdaemon and
>:> > syncer are sleeping when they are told to suspend.  This delays shutdown
>:> > by a few boring seconds.  With this patch, it is zippier.  I expect people
>:> > to complain about this shortcut, but every sleeping process should expect
>:> > to be woken for no reason at all.  Basic kernel premise.
>:> You better bet it's controversial, this isn't "Basic kernel premise"
>:Actually, that depends.  It is definitely poor programming practice to 
>:not check the condition for which you slept on wakeup.
>:> *boom* *crash* *ow* :)
>:Doctor:  So don't do that.
>    I gotta agree.  This is very bad programming practice.  There are many,
>    many places in the kernel where tsleep() is called with a 0 delay and
>    assumed not to return until something meaningful happens.  For example,
>    for handling NFS retries, some of the locking code (I think), and I
>    could probably find many others.

Then this code should be changed to do the right thing, which is
to *always* check the condition being slept on before proceeding.

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
[EMAIL PROTECTED]         | TCP/IP since RFC 956
FreeBSD coreteam member | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.

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