Hello,
on 5/31/2024 2:33 AM, Tejun Heo wrote:
> Hello,
>
> On Tue, May 14, 2024 at 08:52:54PM +0800, Kemeng Shi wrote:
>> +static void balance_wb_limits(struct dirty_throttle_control *dtc,
>> + bool strictlimit)
>> +{
>> + wb_dirty_freerun(dtc, strictlimit);
>> + if (dtc->freerun)
>> + return;
>> +
>> + wb_dirty_exceeded(dtc, strictlimit);
>> + wb_position_ratio(dtc);
>> +}
> ...
>> @@ -1869,12 +1880,9 @@ static int balance_dirty_pages(struct bdi_writeback *wb,
>> * Calculate global domain's pos_ratio and select the
>> * global dtc by default.
>> */
>> - wb_dirty_freerun(gdtc, strictlimit);
>> + balance_wb_limits(gdtc, strictlimit);
>> if (gdtc->freerun)
>> goto free_running;
>> -
>> - wb_dirty_exceeded(gdtc, strictlimit);
>> - wb_position_ratio(gdtc);
>> sdtc = gdtc;
>
> Isn't this a bit nasty? The helper skips updating states because it knows
> the caller is not going to use them? I'm not sure the slight code reduction
> justifies the added subtlety.
It's a general rule that wb should not be limited if the wb is in freerun state.
So I think it's intuitive to obey the rule in both balance_wb_limits and it's
caller in which case balance_wb_limits and it's caller should stop to do anything
when freerun state of wb is first seen.
But no insistant on this...
Thanks.
>
> Thanks.
>
