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Subject: Re: [PATCH v2] fs/dcache.c: avoid soft-lockup in dput()
To: Boqun Feng <boqun.feng@gmail.com>
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 <20160622065128.GB28443@insomnia>
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From: Wei Fang <fangwei1@huawei.com>
Message-ID: <577C6EA9.6050703@huawei.com>
Date: Wed, 6 Jul 2016 10:36:25 +0800
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Hi, Boqun,

>> diff --git a/fs/dcache.c b/fs/dcache.c
>> index d5ecc6e..074fc1c 100644
>> --- a/fs/dcache.c
>> +++ b/fs/dcache.c
>> @@ -578,7 +578,7 @@ static struct dentry *dentry_kill(struct dentry *dentry)
>>  
>>  failed:
>>  	spin_unlock(&dentry->d_lock);
>> -	cpu_relax();
>> +	cond_resched();
> 
> Is it better to put the cond_resched() in the caller(i.e. dput()), right
> before "goto repeat"? Because it's obviously a loop there, which makes
> the purpose of cond_resched() more straightforward.

Agreed, that's more reasonable. I'll send v3 soon.

Thanks,
Wei