Searched hist:"3301 bc53358a0eb0a0db65fd7a513cd4cb50c83a" (Results 1 – 2 of 2) sorted by relevance
/openbmc/linux/include/linux/ |
H A D | sbitmap.h | diff 3301bc53358a0eb0a0db65fd7a513cd4cb50c83a Mon Jan 10 01:29:45 CST 2022 Ming Lei <ming.lei@redhat.com> lib/sbitmap: kill 'depth' from sbitmap_word
Only the last sbitmap_word can have different depth, and all the others must have same depth of 1U << sb->shift, so not necessary to store it in sbitmap_word, and it can be retrieved easily and efficiently by adding one internal helper of __map_depth(sb, index).
Remove 'depth' field from sbitmap_word, then the annotation of ____cacheline_aligned_in_smp for 'word' isn't needed any more.
Not see performance effect when running high parallel IOPS test on null_blk.
This way saves us one cacheline(usually 64 words) per each sbitmap_word.
Cc: Martin Wilck <martin.wilck@suse.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Martin Wilck <mwilck@suse.com> Reviewed-by: John Garry <john.garry@huawei.com> Link: https://lore.kernel.org/r/20220110072945.347535-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
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/openbmc/linux/lib/ |
H A D | sbitmap.c | diff 3301bc53358a0eb0a0db65fd7a513cd4cb50c83a Mon Jan 10 01:29:45 CST 2022 Ming Lei <ming.lei@redhat.com> lib/sbitmap: kill 'depth' from sbitmap_word
Only the last sbitmap_word can have different depth, and all the others must have same depth of 1U << sb->shift, so not necessary to store it in sbitmap_word, and it can be retrieved easily and efficiently by adding one internal helper of __map_depth(sb, index).
Remove 'depth' field from sbitmap_word, then the annotation of ____cacheline_aligned_in_smp for 'word' isn't needed any more.
Not see performance effect when running high parallel IOPS test on null_blk.
This way saves us one cacheline(usually 64 words) per each sbitmap_word.
Cc: Martin Wilck <martin.wilck@suse.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Martin Wilck <mwilck@suse.com> Reviewed-by: John Garry <john.garry@huawei.com> Link: https://lore.kernel.org/r/20220110072945.347535-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
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