From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bart Van Assche Subject: Re: [ANNOUNCE] SRP: ProfitBricks publishes its SRP Initiator patches Date: Mon, 06 May 2013 11:44:17 +0200 Message-ID: <51877B71.3080202@acm.org> References: <5167EDC8.3030909@profitbricks.com> <5183A355.5090401@acm.org> <51876D79.50003@profitbricks.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <51876D79.50003-EIkl63zCoXaH+58JC4qpiA@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Sebastian Riemer Cc: Vasiliy Tolstov , Dongsu Park , linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, David Dillow , Or Gerlitz , scst-devel List-Id: linux-rdma@vger.kernel.org On 05/06/13 10:44, Sebastian Riemer wrote: > Sorry Bart, but a reconnect with just the commit message > "IB/srp: Add kernel-level transport layer recovery" and no further > description isn't very trustworthy for me. I also wonder why you need so > much locking. Hello Sebastian, There is a very good reason for all that locking: during device removal the rport structure is freed before SCSI host removal finished. So when converting a SCSI host pointer into an rport pointer protection is needed against device removal. The current approach in the ib_srp-backport repository is to realize that protection via locking. I'm currently reworking that approach into protection via reference counting such that it is guaranteed that the rport remains to exist until scsi_remove_device() has finished. That will allow to eliminate several locking statements. Sorry for the terse patch descriptions - I had not expected that anyone would try to understand the patches ib_srp-backport repository and use these as a basis for further work. Bart. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html