Subject: Re: [PATCH] md: Fix unexpected behaviour in is_mddev_idle
To:     Luis Chamberlain <mcgrof@kernel.org>
CC:     <song@kernel.org>, <axboe@kernel.dk>, <hare@suse.de>,
        <jack@suse.cz>, <ming.lei@redhat.com>, <tj@kernel.org>,
        <linux-raid@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <linfeilong@huawei.com>
References: <20211201032712.3684503-1-lijinlin3@huawei.com>
 <Yad9phRUdKF/giGD@bombadil.infradead.org>
From:   Li Jinlin <lijinlin3@huawei.com>
Message-ID: <cc737240-a6d2-2c12-d9c8-877c8018b505@huawei.com>
Date:   Thu, 2 Dec 2021 13:07:21 +0800
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On 12/1/2021 9:50 PM, Luis Chamberlain wrote:
> On Wed, Dec 01, 2021 at 11:27:12AM +0800, Li Jinlin wrote:
>> diff --git a/drivers/md/md.c b/drivers/md/md.c
>> index 5111ed966947..f47035838c43 100644
>> --- a/drivers/md/md.c
>> +++ b/drivers/md/md.c
>> @@ -8429,14 +8429,14 @@ static int is_mddev_idle(struct mddev *mddev, int init)
>>  {
>>  	struct md_rdev *rdev;
>>  	int idle;
>> -	int curr_events;
>> +	long curr_events;
> 
>>  
>>  	idle = 1;
>>  	rcu_read_lock();
>>  	rdev_for_each_rcu(rdev, mddev) {
>>  		struct gendisk *disk = rdev->bdev->bd_disk;
>> -		curr_events = (int)part_stat_read_accum(disk->part0, sectors) -
>> -			      atomic_read(&disk->sync_io);
>> +		curr_events = (long)part_stat_read_accum(disk->part0, sectors) -
>> +			      atomic64_read(&disk->sync_io);
> 
> And what makes you believe you might not have to go and change all other
> drivers to address this as well? 
The drdb driver also have same problem. I will resend this patch together with
the fix patch of drdb driver.

Thanks,
JinLin


> 
>>  static inline void md_sync_acct_bio(struct bio *bio, unsigned long nr_sectors)
>> diff --git a/include/linux/genhd.h b/include/linux/genhd.h
>> index 74c410263113..efa7884de11b 100644
>> --- a/include/linux/genhd.h
>> +++ b/include/linux/genhd.h
>> @@ -150,7 +150,7 @@ struct gendisk {
>>  	struct list_head slave_bdevs;
>>  #endif
>>  	struct timer_rand_state *random;
>> -	atomic_t sync_io;		/* RAID */
>> +	atomic64_t sync_io;		/* RAID */
>>  	struct disk_events *ev;
>>  #ifdef  CONFIG_BLK_DEV_INTEGRITY
>>  	struct kobject integrity_kobj;
>> -- 
>> 2.31.1
> 
>   Luis
> .
>