Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756423AbbEVGXc (ORCPT ); Fri, 22 May 2015 02:23:32 -0400 Received: from cantor2.suse.de ([195.135.220.15]:41580 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750707AbbEVGXb (ORCPT ); Fri, 22 May 2015 02:23:31 -0400 Message-ID: <555ECB60.4090406@suse.de> Date: Fri, 22 May 2015 08:23:28 +0200 From: Hannes Reinecke User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: "Nicholas A. Bellinger" , target-devel CC: linux-scsi , linux-kernel , Christoph Hellwig , Sagi Grimberg , "Paul E. McKenney" , Nicholas Bellinger Subject: Re: [PATCH-v2 0/9] target: se_node_acl + se_lun RCU conversions References: <1432275071-28882-1-git-send-email-nab@daterainc.com> In-Reply-To: <1432275071-28882-1-git-send-email-nab@daterainc.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2465 Lines: 62 On 05/22/2015 08:11 AM, Nicholas A. Bellinger wrote: > From: Nicholas Bellinger > > Hi all, > > Here is -v2 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. > > This series also squashes a number of previous se_node_acl RCU > related changes into a single commit (#1) for easier review, > and to avoid potential bisect issues. > > There have been a number of changes since -v1, including: > > - Mirror port->sep_rtpi in lun->lun_rtpi for RCU > - Drop unnecessary synchronize_rcu() usage > - Convert call_rcu() to kfree_rcu() usage > - Move hlist_del_rcu head of rcu_assign_pointer in se_dev_entry > - Drop unnecessary lookup deve in target_fabric_mappedlun_unlink() > - Add target_lun_is_rdonly helper > - Acquire lun_entry_mutex during core_disable_device_list_for_node > - Drop TRANSPORT_LUNFLAGS_*_ACCESS usage > - Pass se_dev_entry directly to core_disable_device_list_for_node > - Convert sbp-target se_lun usage to use ->login_lun > - Fix se_session dereference in spc_emulate_report_luns > - Fix testing for NULL instead of IS_ERR in fabric_make_lun() > - Convert BUG_ON to EINVAL for wrong dynamic -> explicit ACL conversion > - Add missing hlist_del_rcu when swapping orig with new > - Add HBA_FLAGS_INTERNAL_USE checks in add/remove lun > > Please review. > Very nice. Reviewed-by: Hannes Reinecke Although it would be _perfect_ if you could move to full 64-bit LUNs; now that the LUN array is gone there is no need to have a limitation on the number of LUNs, and we can trivially support 64-bit LUNs ... But then, I can easily send a patch once this one is in. Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage hare@suse.de +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N?rnberg GF: F. Imend?rffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton HRB 21284 (AG N?rnberg) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/