linux-kernel - RE: [PATCH] genirq/affinity: Spread IRQs to all available NUMA nodes

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: <CY4PR21MB077387C5E70FD9D96D00FE62D7CF0@CY4PR21MB0773.namprd21.prod.outlook.com>
Date:   Fri, 2 Nov 2018 17:37:43 +0000
From:   Michael Kelley <mikelley@...rosoft.com>
To:     Long Li <longli@...rosoft.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: RE: [PATCH] genirq/affinity: Spread IRQs to all available NUMA nodes

From: Long Li <longli@...rosoft.com>  Sent: Thursday, November 1, 2018 4:52 PM
> 
> --- a/kernel/irq/affinity.c
> +++ b/kernel/irq/affinity.c
> @@ -117,12 +117,13 @@ static int irq_build_affinity_masks(const struct irq_affinity *affd,
>  	 */
>  	if (numvecs <= nodes) {
>  		for_each_node_mask(n, nodemsk) {
> -			cpumask_copy(masks + curvec, node_to_cpumask[n]);
> -			if (++done == numvecs)
> -				break;
> +			cpumask_or(masks + curvec, masks + curvec, node_to_cpumask[n]);
> +			done++;
>  			if (++curvec == last_affv)
>  				curvec = affd->pre_vectors;
>  		}

When the above for loop is exited, 'done' will always be equal to 'nodes' since
there are no early exits from the loop.  Hence there's no need to be
incrementing 'done' in the loop. 

> +		if (done > numvecs)
> +			done = numvecs;

And if 'done' would always be equal to 'nodes', there is no need for the test.
Just always set 'done' to 'numvecs'.

>  		goto out;
>  	}
> 
> --
> 2.14.1