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Date: Tue, 12 Apr 2005 17:10:22 +0200
From: Divacky Roman <xdivac02@stud.fit.vutbr.cz>
To: Vladislav Shabanov <vs@rambler-co.ru>
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cc: hackers@freebsd.org
Subject: Re: do-nothing code in sysv_shm.c
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On Mon, Apr 11, 2005 at 08:03:24PM +0400, Vladislav Shabanov wrote:
> I`ve found the following code in sysv_shm.c :
> 
> ............
> static void
> shminit()
> {
>         int i;
> 
>         TUNABLE_INT_FETCH("kern.ipc.shmmaxpgs", &shminfo.shmall);
>         for (i = PAGE_SIZE; i > 0; i--) {
>                 shminfo.shmmax = shminfo.shmall * PAGE_SIZE;
>                 if (shminfo.shmmax >= shminfo.shmall)
>                         break;
>         }
>         TUNABLE_INT_FETCH("kern.ipc.shmmin", &shminfo.shmmin);
> .........
> 
> IMHO, loop does nothing. Possible variant:

alfred perlstein commited this saying:
Bring shm functions closer the the opengroup standards.

he is the person you should ask why is it coded this way. imho compiler just
optimizes this out leaving plain shminfo.shmmax = shminfo.shmall * PAGE_SIZE;

roman