[dpdk-dev] [PATCH v3 5/5] config: add WFE config entry for aarch64

[Gavin Hu <gavin.hu@arm.com>]

Add the RTE_USE_WFE configuration entry for aarch64, disabled by default.
It can be enabled selectively based on the performance benchmarking.

Signed-off-by: Gavin Hu <gavin.hu@arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
Reviewed-by: Steve Capper <steve.capper@arm.com>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
Acked-by: Pavan Nikhilesh <pbhagavatula@marvell.com>
---
 config/arm/meson.build     | 1 +
 config/common_armv8a_linux | 6 ++++++
 2 files changed, 7 insertions(+)

diff --git a/config/arm/meson.build b/config/arm/meson.build
index 979018e..496813a 100644
--- a/config/arm/meson.build
+++ b/config/arm/meson.build
@@ -116,6 +116,7 @@ impl_dpaa = ['NXP DPAA', flags_dpaa, machine_args_generic]
 impl_dpaa2 = ['NXP DPAA2', flags_dpaa2, machine_args_generic]
 
 dpdk_conf.set('RTE_FORCE_INTRINSICS', 1)
+dpdk_conf.set('RTE_USE_WFE', 0)
 
 if not dpdk_conf.get('RTE_ARCH_64')
 	dpdk_conf.set('RTE_CACHE_LINE_SIZE', 64)
diff --git a/config/common_armv8a_linux b/config/common_armv8a_linux
index 481712e..48c7ab5 100644
--- a/config/common_armv8a_linux
+++ b/config/common_armv8a_linux
@@ -12,6 +12,12 @@ CONFIG_RTE_ARCH_64=y
 
 CONFIG_RTE_FORCE_INTRINSICS=y
 
+# Use WFE instructions to implement the rte_wait_for_equal_xxx APIs,
+# calling these APIs put the cores enter low power state while waiting
+# for the memory address to be become equal to the expected value.
+# This is supported only by aarch64.
+CONFIG_RTE_USE_WFE=n
+
 # Maximum available cache line size in arm64 implementations.
 # Setting to maximum available cache line size in generic config
 # to address minimum DMA alignment across all arm64 implementations.
-- 
2.7.4