From: Christoph Hellwig Subject: Re: [RFC 12/12] iscsi-target: Add Makefile/Kconfig and update TCM top level Date: Thu, 3 Mar 2011 09:19:28 -0500 Message-ID: <20110303141928.GA25256@infradead.org> References: <1299036841-23677-1-git-send-email-nab@linux-iscsi.org> <1299036841-23677-13-git-send-email-nab@linux-iscsi.org> <20110301223251.11c95eed.rdunlap@xenotime.net> <1299101531.5401.313.camel@haakon2.linux-iscsi.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Randy Dunlap , linux-scsi , linux-kernel , linux-crypto@vger.kernel.org, James Bottomley To: "Nicholas A. Bellinger" Return-path: Content-Disposition: inline In-Reply-To: <1299101531.5401.313.camel@haakon2.linux-iscsi.org> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org On Wed, Mar 02, 2011 at 01:32:11PM -0800, Nicholas A. Bellinger wrote: > The kernel code itself that is specific to using the SSE v4.2 > instruction for CRC32C offload are using #ifdef CONFIG_X86 stubs in > iscsi_target_login.c:iscsi_login_setup_crypto(), and !CONFIG_X86 will > default to using the unoptimized 1x8 slicing soft CRC32C code. This > particular piece of logic has been tested on powerpc and arm and is > funcitoning as expected from the kernel level using the arch independent > soft code. I don't think you need that code at all. The crypto code is structured to prefer the optimized implementation if it is present. Just stripping the x86-specific code out and always requesting the plain crc32c algorithm should give you the optimized one if it is present on your system. Please give it a try.