netdev - Re: [PATCH net-next v2 4/8] net: napi: add CPU affinity to napi->config

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 for Android: free password hash cracker in your pocket

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

Message-ID: <cf836232-ef2b-40c8-b9e5-4f0dffdcc839@intel.com>
Date: Fri, 20 Dec 2024 07:51:09 -0700
From: Ahmed Zaki <ahmed.zaki@...el.com>
To: Jakub Kicinski <kuba@...nel.org>
CC: <netdev@...r.kernel.org>, <intel-wired-lan@...ts.osuosl.org>,
	<andrew+netdev@...n.ch>, <edumazet@...gle.com>, <pabeni@...hat.com>,
	<davem@...emloft.net>, <michael.chan@...adcom.com>, <tariqt@...dia.com>,
	<anthony.l.nguyen@...el.com>, <przemyslaw.kitszel@...el.com>,
	<jdamato@...tly.com>, <shayd@...dia.com>, <akpm@...ux-foundation.org>
Subject: Re: [PATCH net-next v2 4/8] net: napi: add CPU affinity to
 napi->config



On 2024-12-19 8:42 p.m., Jakub Kicinski wrote:
> On Wed, 18 Dec 2024 09:58:39 -0700 Ahmed Zaki wrote:
>> +	if (!glue_created && flags & NAPIF_IRQ_AFFINITY) {
>> +		glue = kzalloc(sizeof(*glue), GFP_KERNEL);
>> +		if (!glue)
>> +			return;
>> +		glue->notify.notify = netif_irq_cpu_rmap_notify;
>> +		glue->notify.release = netif_napi_affinity_release;
>> +		glue->data = napi;
>> +		glue->rmap = NULL;
>> +		napi->irq_flags |= NAPIF_IRQ_NORMAP;
> 
> Why allocate the glue? is it not possible to add the fields:
> 
> 	struct irq_affinity_notify notify;
> 	u16 index;
> 
> to struct napi_struct ?

In the first branch of "if", the cb function netif_irq_cpu_rmap_notify() 
is also passed to irq_cpu_rmap_add() where the irq notifier is embedded 
in "struct irq_glue".

I think this cannot be changed as long as some drivers are directly 
calling irq_cpu_rmap_add() instead of the proposed API.