Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <1a9c4365-aae1-b4fe-d31d-dfd9b42afae6@bytedance.com>
Date:   Fri, 14 Apr 2023 22:13:30 +0800
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0)
 Gecko/20100101 Thunderbird/102.9.1
Subject: Re: Re: [PATCH V5 4/5] cachefiles: narrow the scope of triggering
 EPOLLIN events in ondemand mode
To:     David Howells <dhowells@redhat.com>
Cc:     linux-cachefs@redhat.com, linux-erofs@lists.ozlabs.org,
        linux-kernel@vger.kernel.org, jefflexu@linux.alibaba.com,
        hsiangkao@linux.alibaba.com, yinxin.x@bytedance.com,
        zhujia.zj@bytedance.com
References: <20230329140155.53272-5-zhujia.zj@bytedance.com>
 <20230329140155.53272-1-zhujia.zj@bytedance.com>
 <1250225.1681480128@warthog.procyon.org.uk>
From:   Jia Zhu <zhujia.zj@bytedance.com>
In-Reply-To: <1250225.1681480128@warthog.procyon.org.uk>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit
Precedence: bulk


在 2023/4/14 21:48, David Howells 写道:
> Jia Zhu <zhujia.zj@bytedance.com> wrote:
> 
>>   	if (cachefiles_in_ondemand_mode(cache)) {
>> -		if (!xa_empty(&cache->reqs))
>> -			mask |= EPOLLIN;
>> +		if (!xa_empty(xa)) {
>> +			rcu_read_lock();
>> +			xa_for_each_marked(xa, index, req, CACHEFILES_REQ_NEW) {
>> +				if (!cachefiles_ondemand_is_reopening_read(req)) {
>> +					mask |= EPOLLIN;
>> +					break;
>> +				}
>> +			}
>> +			rcu_read_unlock();
> 
> You should probably use xas_for_each_marked() instead of xa_for_each_marked()
> as the former should perform better.
> 
> David

Hi David,

Thanks for your advice. I'll revise it in next version.

Jia
>