[Devel] [PATCH vz9 v1 33/63] dm-ploop: convert md page rw lock to spin lock

[Alexander Atanasov]

On 6.02.25 10:42, Pavel Tikhomirov wrote:
> 
> 
> On 1/24/25 23:36, Alexander Atanasov wrote:
>> diff --git a/drivers/md/dm-ploop-cmd.c b/drivers/md/dm-ploop-cmd.c
>> index f98542e952e1..fa9f8c9d8d40 100644
>> --- a/drivers/md/dm-ploop-cmd.c
>> +++ b/drivers/md/dm-ploop-cmd.c
>> @@ -34,7 +34,7 @@ static void ploop_advance_holes_bitmap(struct ploop 
>> *ploop,
>>           return;
>>       cmd->resize.stage++;
>> -    write_lock_irq(&ploop->bat_rwlock);
>> +    write_lock_irqsave(&ploop->bat_rwlock, flags);
> 
> Why s/irq/irqsave/ ?
> 
>    +-< ploop_advance_holes_bitmap
>      +-< ploop_process_resize_cmd
>      | +-< ploop_resize
>      | | +-< ploop_message
>            +-< ploop_target->message
>              +-< target_message # ioctl - process context


Well, this is only used in cmds you may be right here.

> 
> It can't be called in interrupt context, thus should be "_irq".
> 
>>       /* Copy and swap holes_bitmap */
>>       size = DIV_ROUND_UP(ploop->hb_nr, 8);
>>       memcpy(cmd->resize.holes_bitmap, ploop->holes_bitmap, size);
>> @@ -46,7 +46,7 @@ static void ploop_advance_holes_bitmap(struct ploop 
>> *ploop,
>>           ploop_init_be_iter(ploop, md->id, &i, &end);
>>           bat_entries = md->kmpage;
>> -        spin_lock_irqsave(&md->md_lock, flags); /* read */
>> +        spin_lock(&md->md_lock); /* read */
>>           for (; i <= end; i++) {
>>               if (!ploop_md_page_cluster_is_in_top_delta(ploop, md, i))
>>                   continue;
>> @@ -57,9 +57,9 @@ static void ploop_advance_holes_bitmap(struct ploop 
>> *ploop,
>>                   ploop_hole_clear_bit(dst_clu, ploop);
>>               }
>>           }
>> -        spin_unlock_irqrestore(&md->md_lock, flags);
>> +        spin_unlock(&md->md_lock);
>>       }
>> -    write_unlock_irq(&ploop->bat_rwlock);
>> +    write_unlock_irqrestore(&ploop->bat_rwlock, flags);
> 
> Same.
> 
>>   }
>>   static int ploop_wait_for_completion_maybe_killable(struct 
>> completion *comp,
> 

-- 
Regards,
Alexander Atanasov