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Message-ID: <a0a07bfd-6e44-5478-395d-be6c1f3bd92a@linux.alibaba.com>
Date:   Sat, 10 Jun 2023 11:20:49 +0800
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Subject: Re: [PATCH 1/3] virtio-crypto: fixup potential cpu stall when free
 unused bufs
To:     "Michael S. Tsirkin" <mst@redhat.com>
Cc:     arei.gonglei@huawei.com, jasowang@redhat.com,
        xuanzhuo@linux.alibaba.com, herbert@gondor.apana.org.au,
        davem@davemloft.net, amit@kernel.org, arnd@arndb.de,
        gregkh@linuxfoundation.org, marcel@holtmann.org,
        johan.hedberg@gmail.com, luiz.dentz@gmail.com,
        linux-bluetooth@vger.kernel.org,
        virtualization@lists.linux-foundation.org,
        linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org,
        Xianting Tian <tianxianting.txt@alibaba-inc.com>
References: <20230609131817.712867-1-xianting.tian@linux.alibaba.com>
 <20230609131817.712867-2-xianting.tian@linux.alibaba.com>
 <20230609115617-mutt-send-email-mst@kernel.org>
From:   Xianting Tian <xianting.tian@linux.alibaba.com>
In-Reply-To: <20230609115617-mutt-send-email-mst@kernel.org>
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在 2023/6/9 下午11:57, Michael S. Tsirkin 写道:
> On Fri, Jun 09, 2023 at 09:18:15PM +0800, Xianting Tian wrote:
>> From: Xianting Tian <tianxianting.txt@alibaba-inc.com>
>>
>> Cpu stall issue may happen if device is configured with multi queues
>> and large queue depth, so fix it.
> What does "may happen" imply exactly?
> was this observed?
I didn't met such issue, this patch set just a theoretical fix.
>
>> Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com>
>> ---
>>   drivers/crypto/virtio/virtio_crypto_core.c | 1 +
>>   1 file changed, 1 insertion(+)
>>
>> diff --git a/drivers/crypto/virtio/virtio_crypto_core.c b/drivers/crypto/virtio/virtio_crypto_core.c
>> index 1198bd306365..94849fa3bd74 100644
>> --- a/drivers/crypto/virtio/virtio_crypto_core.c
>> +++ b/drivers/crypto/virtio/virtio_crypto_core.c
>> @@ -480,6 +480,7 @@ static void virtcrypto_free_unused_reqs(struct virtio_crypto *vcrypto)
>>   			kfree(vc_req->req_data);
>>   			kfree(vc_req->sgs);
>>   		}
>> +		cond_resched();
>>   	}
>>   }
>>   
>> -- 
>> 2.17.1