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This should speed up repeated > > querying of CPU flags, and provides a workaround for a reported issue where > > errors are seen with constant querying of the AVX-512 CPU flag from a non- > > AVX VM. > > > > Bugzilla Id: 1501 > > > > Signed-off-by: Bruce Richardson > > --- > > Hi Bruce, > Why x86/rte_cpuflags.c is not using rte_getauxval() ? I don't see any such DPDK function, unless I'm missing something? I do see a linux function which includes hw capability flags. I suspect the reasons we don't use that are: 1. Lack of awareness of it (at least on my end! :-)) 2. Originally when we added flags for new instruction sets we may have needed to support their detection on platforms where the kernel/libc was too old to be aware of them. 3. It's linux only, so we'd still need these cpuid calls for other OS's anyway. Therefore, I don't see any benefit in using that function over what we do now. Is there some benefit that you see that makes you think it would be worthwhile switching? Thanks, /Bruce