[PATCH v3] erofs: convert workstn to XArray

[Chao Yu]

On 2020/2/20 10:46, Gao Xiang wrote:
> XArray has friendly APIs and it will replace the old radix
> tree in the near future.
> 
> This convert makes use of __xa_cmpxchg when inserting on
> a just inserted item by other thread. In detail, instead
> of totally looking up again as what we did for the old
> radix tree, it will try to legitimize the current in-tree
> item in the XArray therefore more effective.
> 
> In addition, naming is rather a challenge for non-English
> speaker like me. The basic idea of workstn is to provide
> a runtime sparse array with items arranged in the physical
> block number order. Such items (was called workgroup) can be
> used to record compress clusters or for later new features.
> 
> However, both workgroup and workstn seem not good names from
> whatever point of view, so I'd like to rename them as pslot
> and managed_pslots to stand for physical slots. This patch
> handles the second as a part of the radix tree convert.
> 
> Cc: Chao Yu <yuchao0 at huawei.com>
> Cc: Matthew Wilcox <willy at infradead.org>
> Signed-off-by: Gao Xiang <gaoxiang25 at huawei.com>

Looks good to me.

Reviewed-by: Chao Yu <yuchao0 at huawei.com>

Thanks,