linux-kernel - Re: [PATCH v7 06/10] virtio: blk/scsi: use block layer helpers to constrain queue affinity

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

Message-ID: <8a559a2c-c4f5-4ce2-9e1b-e960cd59fb9f@suse.de>
Date: Thu, 3 Jul 2025 08:43:41 +0200
From: Hannes Reinecke <hare@...e.de>
To: Daniel Wagner <wagi@...nel.org>, Jens Axboe <axboe@...nel.dk>,
 Keith Busch <kbusch@...nel.org>, Christoph Hellwig <hch@....de>,
 Sagi Grimberg <sagi@...mberg.me>, "Michael S. Tsirkin" <mst@...hat.com>
Cc: Aaron Tomlin <atomlin@...mlin.com>,
 "Martin K. Petersen" <martin.petersen@...cle.com>,
 Thomas Gleixner <tglx@...utronix.de>, Costa Shulyupin
 <costa.shul@...hat.com>, Juri Lelli <juri.lelli@...hat.com>,
 Valentin Schneider <vschneid@...hat.com>, Waiman Long <llong@...hat.com>,
 Ming Lei <ming.lei@...hat.com>, Frederic Weisbecker <frederic@...nel.org>,
 Mel Gorman <mgorman@...e.de>,
 Mathieu Desnoyers <mathieu.desnoyers@...icios.com>,
 linux-kernel@...r.kernel.org, linux-block@...r.kernel.org,
 linux-nvme@...ts.infradead.org, megaraidlinux.pdl@...adcom.com,
 linux-scsi@...r.kernel.org, storagedev@...rochip.com,
 virtualization@...ts.linux.dev, GR-QLogic-Storage-Upstream@...vell.com
Subject: Re: [PATCH v7 06/10] virtio: blk/scsi: use block layer helpers to
 constrain queue affinity

On 7/2/25 18:33, Daniel Wagner wrote:
> Ensure that IRQ affinity setup also respects the queue-to-CPU mapping
> constraints provided by the block layer. This allows the virtio drivers
> to avoid assigning interrupts to CPUs that the block layer has excluded
> (e.g., isolated CPUs).
> 
> Signed-off-by: Daniel Wagner <wagi@...nel.org>
> ---
>   drivers/block/virtio_blk.c | 4 +++-
>   drivers/scsi/virtio_scsi.c | 5 ++++-
>   2 files changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
> index e649fa67bac16b4f0c6e8e8f0e6bec111897c355..41b06540c7fb22fd1d2708338c514947c4bdeefe 100644
> --- a/drivers/block/virtio_blk.c
> +++ b/drivers/block/virtio_blk.c
> @@ -963,7 +963,9 @@ static int init_vq(struct virtio_blk *vblk)
>   	unsigned short num_vqs;
>   	unsigned short num_poll_vqs;
>   	struct virtio_device *vdev = vblk->vdev;
> -	struct irq_affinity desc = { 0, };
> +	struct irq_affinity desc = {
> +		.mask = blk_mq_possible_queue_affinity(),
> +	};
>   
>   	err = virtio_cread_feature(vdev, VIRTIO_BLK_F_MQ,
>   				   struct virtio_blk_config, num_queues,
> diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
> index 96a69edddbe5555574fc8fed1ba7c82a99df4472..67dfb265bf9e54adc68978ac8d93187e6629c330 100644
> --- a/drivers/scsi/virtio_scsi.c
> +++ b/drivers/scsi/virtio_scsi.c
> @@ -842,7 +842,10 @@ static int virtscsi_init(struct virtio_device *vdev,
>   	u32 num_vqs, num_poll_vqs, num_req_vqs;
>   	struct virtqueue_info *vqs_info;
>   	struct virtqueue **vqs;
> -	struct irq_affinity desc = { .pre_vectors = 2 };
> +	struct irq_affinity desc = {
> +		.pre_vectors = 2,
> +		.mask = blk_mq_possible_queue_affinity(),
> +	};
>   
>   	num_req_vqs = vscsi->num_queues;
>   	num_vqs = num_req_vqs + VIRTIO_SCSI_VQ_BASE;
> 
Reviewed-by: Hannes Reinecke <hare@...e.de>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@...e.de                                +49 911 74053 688
SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich