From mboxrd@z Thu Jan 1 00:00:00 1970 From: Venky Venkatesan Subject: Re: [PATCH v2 0/2] dpdk: Allow for dynamic enablement of some isolated features Date: Wed, 30 Jul 2014 12:03:38 -0700 Message-ID: <53D9418A.5020308@intel.com> References: <1406665466-29654-1-git-send-email-nhorman@tuxdriver.com> <1406731769-18523-1-git-send-email-nhorman@tuxdriver.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit To: dev-VfR2kkLFssw@public.gmane.org Return-path: In-Reply-To: <1406731769-18523-1-git-send-email-nhorman-2XuSBdqkA4R54TAoqtyWWQ@public.gmane.org> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces-VfR2kkLFssw@public.gmane.org Sender: "dev" Neil, > Hey all- > I've been trying to update the fedora dpdk package to support VFIO > enabled drivers and ran into a problem in which ixgbe didn't compile because the > rxtx_vec code uses sse4.2 instruction intrinsics, which aren't supported in the > default config I have. I tried to remedy this by replacing the intrinsics with > the __builtin macros, but it was pointed out (correctly), that this doesn't work > properly. So this is my second attempt, which I actually like a bit better. I > noted that code that uses intrinsics (ixgbe and the acl library), don't need to > have those instructions turned on build-wide. Rather, we can just enable the > instructions in the specific code we want to build with support for that, and > test for instruction support dynamically at run time. This allows me to build > the dpdk for a generic platform, but in such a way that some optimizations can > be used if the executing cpu supports them at run time. > > Change notes: > > v2) > * Added Log messages to run time check failures per Konstantin > * Removed run time check caching in acl per Konstantin > > Signed-off-by: Neil Horman > CC: Thomas Monjalon > One possible change to look at - the _mm_shuffle_epi8 is something that is available all the way from SSSE3, so you should be able to leave that in. The SSE4.2 dependency is only for the popcount (and __builtin_popcountll will work for that anyway). That should make things simpler. -Venky