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Subject: Re: [PATCH] async: Let kfree() out of the critical area of the lock
To:     Bart Van Assche <bvanassche@acm.org>, <dsterba@suse.cz>,
        <bhelgaas@google.com>, "tglx@linutronix.de" <tglx@linutronix.de>,
        "Alexander Duyck" <alexander.h.duyck@linux.intel.com>,
        <sakari.ailus@linux.intel.com>,
        "gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>,
        David Sterba <dsterba@suse.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
References: <216356b1-38c1-8477-c4e8-03f497dd6ac8@huawei.com>
 <f49df2d42d7e97b61a5e26ff4d89ede5fbe37a35.camel@linux.intel.com>
 <e59af8ae-bacb-2e7e-dd53-ea283960d40e@huawei.com>
 <20190926110648.GM2751@suse.cz>
 <e339db78-413c-446a-8e07-40e6e1ad4a31@acm.org>
From:   Yunfeng Ye <yeyunfeng@huawei.com>
Message-ID: <cadede43-776e-449d-c6e5-c7f9c2c1acf2@huawei.com>
Date:   Fri, 27 Sep 2019 09:00:41 +0800
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On 2019/9/26 23:18, Bart Van Assche wrote:
> On 9/26/19 4:06 AM, David Sterba wrote:
>> On Thu, Sep 26, 2019 at 03:58:36PM +0800, Yunfeng Ye wrote:
>>> The async_lock is big global lock, I think it's good to put kfree() outside
>>> to keep the critical area as short as possible.
>>
>> Agreed, kfree is not always cheap. We had patches in btrfs moving kfree
>> out of critical section(s) after causing softlockups due to increased lock
>> contention.
> 
> The above would be a great addition for the commit description. Anyway:
> 
ok, I will update the description, thanks.

> Reviewed-by: Bart Van Assche <bvanassche@acm.org>
> 
> .
>