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From: Sergey Fedorov <serge.fdrv@gmail.com>
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Date: Mon, 18 Jul 2016 20:31:49 +0300
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Subject: Re: [Qemu-devel] [PATCH] atomics: add volatile_read/volatile_set
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To: Paolo Bonzini <pbonzini@redhat.com>, qemu-devel@nongnu.org
Cc: sergey.fedorov@linaro.org, alex.bennee@linaro.org

On 18/07/16 20:28, Paolo Bonzini wrote:
>
> On 18/07/2016 19:25, Sergey Fedorov wrote:
>>>> @@ -753,14 +753,14 @@ static inline void cpu_get_invalid_tb_cpu_state(target_ulong *pc,
>>>>                                                  target_ulong *cs_base,
>>>>                                                  uint32_t *flags)
>>>>  {
>>>> -    *cs_base = -1; /* npc must be a multible of 4 */
>>>> +    *flags = TB_FLAG_MMU_MASK;
>>>>  }
>> Hmm, not sure if it is really simpler to follow. Maybe " |= 1;" anyway?
> |= 1 has the problem that tb_mark_invalid doesn't pass TB's tuple into
> cpu_get_invalid_tb_cpu_state, and I didn't want to change that.  I'll
> add a comment,
>
>     /* TB_FLAG_MMU_MASK is not a valid MMU index, which makes it is an
>      * impossible flag combination for valid TBs.
>      */
>

I wonder if using a dedicated field to mark TBs invalid would be so slow
that we couldn't afford it...

Kind regards,
Sergey