[PATCH v7 09/10] blk-mq: prevent offlining hk CPUs with associated online isolated CPUs

[Hannes Reinecke]

On 7/2/25 18:33, Daniel Wagner wrote:
> When isolcpus=io_queue is enabled, and the last housekeeping CPU for a
> given hctx goes offline, there would be no CPU left to handle I/O. To
> prevent I/O stalls, prevent offlining housekeeping CPUs that are still
> serving isolated CPUs.
> 
> When isolcpus=io_queue is enabled and the last housekeeping CPU
> for a given hctx goes offline, no CPU would be left to handle I/O.
> To prevent I/O stalls, disallow offlining housekeeping CPUs that are
> still serving isolated CPUs.
> 
> Signed-off-by: Daniel Wagner <wagi at kernel.org>
> ---
>   block/blk-mq.c | 42 ++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 42 insertions(+)
> 
Reviewed-by: Hannes Reinecke <hare at suse.de>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare at suse.de                                +49 911 74053 688
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