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Re: [XenPPC] [RFC] fix stupid grant table flags

To: Jimi Xenidis <jimix@xxxxxxxxxxxxxx>
Subject: Re: [XenPPC] [RFC] fix stupid grant table flags
From: Hollis Blanchard <hollisb@xxxxxxxxxx>
Date: Thu, 22 Jun 2006 14:24:53 -0500
Cc: xen-ppc-devel <xen-ppc-devel@xxxxxxxxxxxxxxxxxxx>
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On Wed, 2006-06-21 at 18:49 -0400, Jimi Xenidis wrote:
>    static inline void  clear_entry_flag(unsigned long nr, volatile  
> uint16_t *addr) {
>        volatile unsigned long *laddr;
>        unsigned long lnr;
>    #ifdef SAFETY_DANCE
>        BUG_ON((ulong)addr % sizeof (ulong));
>    #endif
>        lnr = (BITS_PER_LONG - (sizeof (*addr) * 8)) + nr;
>        laddr = (volatile unsigned long *)addr;
>        clear_bit(lnr, laddr);
>    } 

Why all the "volatile" here? This function isn't dereferencing those
pointers, so it shouldn't matter?

Hollis Blanchard
IBM Linux Technology Center

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