[PATCH] Revert "iommu/arm-smmu-v3: Decrease the queue size of evtq and priq"

Leizhen (ThunderTown) thunder.leizhen at huawei.com
Tue Dec 14 17:59:00 PST 2021



On 2021/12/14 22:48, Will Deacon wrote:
> On Tue, Dec 07, 2021 at 02:32:48PM +0800, Zhou Wang wrote:
>> The commit f115f3c0d5d8 ("iommu/arm-smmu-v3: Decrease the queue size of
>> evtq and priq") decreases evtq and priq, which may lead evtq/priq to be
>> full with fault events, e.g HiSilicon ZIP/SEC/HPRE have maximum 1024 queues
>> in one device, every queue could be binded with one process and trigger a
>> fault event. So let's revert f115f3c0d5d8.
>>
>> In fact, if an implementation of SMMU really does not need so long evtq
>> and priq, value of IDR1_EVTQS and IDR1_PRIQS can be set to proper ones.
>>
>> Signed-off-by: Zhou Wang <wangzhou1 at hisilicon.com>
>> ---
>>  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 5 ++---
>>  1 file changed, 2 insertions(+), 3 deletions(-)
> 
> I'd like an Ack from Zhen Lei on this, as the aim of the original patch
> was to reduce memory consumption.

I did it for the purpose of saving memory. At the time, I didn't think it would
have accumulated so many events. Now there is such a practical situation. Ensuring
functionality stability is more important than saving a little memory. So I have
no objection to reverting my patch.

Acked-by: Zhen Lei <thunder.leizhen at huawei.com>

> 
> Will
> .
> 



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