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Subject: About sbitmap_bitmap_show() and cleared bits (was Re: [PATCH RFC v7
 07/12] blk-mq: Add support in hctx_tags_bitmap_show() for a shared sbitmap)
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From:   John Garry <john.garry@huawei.com>
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Hi all,

I noticed that sbitmap_bitmap_show() only shows set bits and does not 
consider cleared bits. Is that the proper thing to do?

I ask, as from trying to support sbitmap_bitmap_show() for hostwide 
shared tags feature, we currently use blk_mq_queue_tag_busy_iter() to 
find active requests (and associated tags/bits) for a particular hctx. 
So, AFAICT, would give a change in behavior for sbitmap_bitmap_show(), 
in that it would effectively show set and not cleared bits.

Any thoughts on this?

Thanks!