Add support for multiple microarchitectures in single binary

 * compiler -march= parameter is changed from native to corei7
   so code is always genereted with instructions which are available
   on the Nehalem microarchitecture (up to SSE4.2)

 * compiler -mtune= parameter is added so code is optimized for
   corei7-avx which equals to Sandy Bridge microarchitecture

 * set of macros is added which allows run-time detection of available
   cpu instructions (e.g. clib_cpu_supports_avx())

 * set of macros is added which allows us to clone graph node funcitons
   where cloned function is optmized for different microarchitecture
   Those macros are using following attributes:
     __attribute__((flatten))
     __attribute__((target("arch=core-avx2)))

   I.e. If applied to foo_node_fn() macro will generate cloned
   functions foo_node_fn_avx2() and foo_node_fn_avx512() (future)
   It will also generate function void * foo_node_fn_multiarch_select()
   which detects available instruction set and returns pointer to the
   best matching function clone.

Change-Id: I2dce0ac92a5ede95fcb56f47f3d1f3c4c040bac0
Signed-off-by: Damjan Marion <damarion@cisco.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/vnet/vnet/devices/dpdk/cli.c b/vnet/vnet/devices/dpdk/cli.c
index 9ec19867929..9063cad890a 100644
--- a/vnet/vnet/devices/dpdk/cli.c
+++ b/vnet/vnet/devices/dpdk/cli.c
@@ -759,6 +759,7 @@ set_efd (vlib_main_t *vm, unformat_input_t *input,
     dpdk_main_t * dm = &dpdk_main;
     vlib_thread_main_t * tm = vlib_get_thread_main();
     clib_error_t * error = NULL;
+    vlib_node_runtime_t * rt = vlib_node_get_runtime (vm, dpdk_input_node.index);
 
     if (unformat(input, "enable")) {
         if (unformat(input, "dpdk")) {
@@ -844,6 +845,13 @@ set_efd (vlib_main_t *vm, unformat_input_t *input,
                                   format_unformat_error, input);
     }
 
+    if (dm->efd.enabled)
+	rt->function = dpdk_input_efd_multiarch_select();
+    else if (dm->use_rss)
+	rt->function = dpdk_input_rss_multiarch_select();
+    else
+	rt->function = dpdk_input_multiarch_select();
+
     return error;
 }