[dpdk-dev] [PATCH v2] config: make AVX and AVX512 configurable

[Zhihong Wang]

Making AVX and AVX512 configurable is useful for performance and power
testing.

The similar kernel patch at https://patchwork.kernel.org/patch/9618883/.

AVX512 support like in rte_memcpy has been in DPDK since 16.04, but it's
still unproven in rich use cases in hardware. Therefore it's marked as
experimental for now, will enable it after enough field test and possible
optimization.

Signed-off-by: Zhihong Wang <zhihong.wang at intel.com>
---
Changes in v2:

 1. Add comments and explanation.

---
 config/common_base | 8 ++++++++
 mk/rte.cpuflags.mk | 6 ++++++
 2 files changed, 14 insertions(+)

diff --git a/config/common_base b/config/common_base
index 0b4297c..93e9235 100644
--- a/config/common_base
+++ b/config/common_base
@@ -103,6 +103,14 @@ CONFIG_RTE_EAL_IGB_UIO=n
 CONFIG_RTE_EAL_VFIO=n
 CONFIG_RTE_MALLOC_DEBUG=n
 
+#
+# Recognize/ignore the AVX/AVX512 CPU flags for performance/power testing.
+# AVX512 is marked as experimental for now, will enable it after enough
+# field test and possible optimization.
+#
+CONFIG_RTE_ENABLE_AVX=y
+CONFIG_RTE_ENABLE_AVX512=n
+
 # Default driver path (or "" to disable)
 CONFIG_RTE_EAL_PMD_PATH=""
 
diff --git a/mk/rte.cpuflags.mk b/mk/rte.cpuflags.mk
index e634abc..4288c14 100644
--- a/mk/rte.cpuflags.mk
+++ b/mk/rte.cpuflags.mk
@@ -70,8 +70,10 @@ CPUFLAGS += PCLMULQDQ
 endif
 
 ifneq ($(filter $(AUTO_CPUFLAGS),__AVX__),)
+ifeq ($(CONFIG_RTE_ENABLE_AVX),y)
 CPUFLAGS += AVX
 endif
+endif
 
 ifneq ($(filter $(AUTO_CPUFLAGS),__RDRND__),)
 CPUFLAGS += RDRAND
@@ -86,12 +88,16 @@ CPUFLAGS += F16C
 endif
 
 ifneq ($(filter $(AUTO_CPUFLAGS),__AVX2__),)
+ifeq ($(CONFIG_RTE_ENABLE_AVX),y)
 CPUFLAGS += AVX2
 endif
+endif
 
 ifneq ($(filter $(AUTO_CPUFLAGS),__AVX512F__),)
+ifeq ($(CONFIG_RTE_ENABLE_AVX512),y)
 CPUFLAGS += AVX512F
 endif
+endif
 
 # IBM Power CPU flags
 ifneq ($(filter $(AUTO_CPUFLAGS),__PPC64__),)
-- 
2.7.4