netdev - Re: [PATCH] net: sort queues in xps maps

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <e9448591-005f-c21d-892b-18ad523b362b@chinatelecom.cn>
Date:   Thu, 14 Jul 2022 14:04:18 +0800
From:   Yonglong Li <liyonglong@...natelecom.cn>
To:     Jakub Kicinski <kuba@...nel.org>
Cc:     netdev@...r.kernel.org, davem@...emloft.net, edumazet@...gle.com,
        pabeni@...hat.com, alexanderduyck@...com
Subject: Re: [PATCH] net: sort queues in xps maps



On 7/14/2022 11:32 AM, Jakub Kicinski wrote:
> On Thu, 14 Jul 2022 11:24:31 +0800 Yonglong Li wrote:
>>>> @@ -2654,6 +2660,13 @@ int __netif_set_xps_queue(struct net_device *dev, const unsigned long *mask,
>>>>  					  skip_tc);
>>>>  	}
>>>>  
>>>> +	for (j = -1; j = netif_attrmask_next_and(j, online_mask, mask, nr_ids),
>>>> +	     j < nr_ids;) {
>>>> +		tci = j * num_tc + tc;
>>>> +		map = xmap_dereference(new_dev_maps->attr_map[tci]);
>>>> +		sort(map->queues, map->len, sizeof(u16), cmp_u16, NULL);
>>>> +	}
>>>> +  
>>>
>>> Can we instead make sure that expand_xps_map() maintains order?
>>>   
>> expand_xps_map() only alloc new_map and copy old map's queue to new_map.
>> I think it is not suitable to do it in expand_xps_map().
>> WDYT?
> 
> Oh, right, sorry for the confusion, I assumed since it reallocates that
> it also fills the entry. It probably doesn't to make sure that all
> allocations succeed before making any modifications.
> 
> Can we factor out the inside of the next loop - starting from the 
> "add tx-queue to CPU/rx-queue maps" comment into a helper? My worry is
> that __netif_set_xps_queue() is already pretty long and complicated we
> should try to move some code out rather than make it longer.
>
Ok, I will prepare a v2 patch as your suggestion.


-- 
Li YongLong