+CC techboard > From: Maxime Coquelin [mailto:maxime.coque...@redhat.com] > Sent: Friday, 29 March 2024 14.05 > > Hi Stephen, > > On 3/29/24 03:53, Stephen Hemminger wrote: > > On Thu, 28 Mar 2024 17:10:42 -0700 > > Andrey Ignatov <r...@apple.com> wrote: > > > >>> > >>> You don't need always inline, the compiler will do it anyway. > >> > >> I can remove it in v2, but it's not completely obvious to me how is > it > >> decided when to specify it explicitly and when not? > >> > >> I see plenty of __rte_always_inline in this file: > >> > >> % git grep -c '^static __rte_always_inline' lib/vhost/virtio_net.c > >> lib/vhost/virtio_net.c:66 > > > > > > Cargo cult really. > > > > Cargo cult... really? > > Well, I just did a quick test by comparing IO forwarding with testpmd > between main branch and with adding a patch that removes all the > inline/noinline in lib/vhost/virtio_net.c [0]. > > main branch: 14.63Mpps > main branch - inline/noinline: 10.24Mpps
Thank you for testing this, Maxime. Very interesting! It is sometimes suggested on techboard meetings that we should convert more inline functions to non-inline for improved API/ABI stability, with the argument that the performance of inlining is negligible. I think this test proves that the sum of many small (negligible) performance differences it not negligible! > > Andrey, thanks for the patch, I'll have a look at it next week. > > Maxime > > [0]: https://pastebin.com/72P2npZ0
