Re: [PATCH-v3 00/10] target: se_node_acl + se_lun RCU conversions

[Hannes Reinecke <hare@suse.de>]

On 05/26/2015 08:25 AM, Nicholas A. Bellinger wrote:
> From: Nicholas Bellinger <nab@linux-iscsi.org>
> 
> Hi all,
> 
> Here is -v3 series for converting LIO target se_node_acl + se_lun
> mapping tables from fixed size arrays to dynamic RCU hlist_heads.
> 
> This turns fast-path I/O into a lock-less RCU reader using existing
> percpu based se_lun->lun_ref logic, and converts the RCU updater
> path to allow for an arbitrary number of LUNs for both types of
> mappings within target-core.
> 
> As per this afternoon's email thread, the se_dev_entry->pr_comp
> has been left in place for se_dev_entry shutdown within patch #1.
> This completion is still required in order to prevent the configfs
> se_lun_acl->se_lun_group from being removed from out below the
> core_scsi3_lunacl_depend_item() caller during the special-case PR
> ALL_TG_PT=1 registration handling.
> 
> The changes based on -v2 series feedback from HCH & Co include:
> 
>   - Remove unused se_dev_entry->se_node_acl
>   - Drop unnecessary check in lunacl_undepend_item
>   - target: Drop bogus mutex_unlock in core_disable_device_list_for_node
>   - Drop left-over se_lun->lun_status
>   - target: Rename ->pr_regs to ->deve_flags + add bit definitions
>   - target: Convert se_dev_entry stats to atomic_long_t
>   - Avoid unnecessary PR target_nacl_find_deve() lookup in registration
>   - Add se_lun->lun_index for RCU dev->dev_index usage in stat.c
>   - Add various rcu_dereference and lockless_dereference RCU notation
> 
> Please review.
> 
> --nab
> 
For the whole series:

Reviewed-by: Hannes Reinecke <hare@suse.de>

Do you have a git tree for these changes?
As mentioned earlier, it should be fairly trivial to convert
LIO target to use 64-bit LUNs with this patchset.

Cheers,

Hannes
-- 
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