This commit adds a new command to allow the user to switch
the active DPIF implementation at runtime. A probe function
is executed before switching the DPIF implementation, to ensure
the CPU is capable of running the ISA required. For example, the
below code will switch to the AVX512 enabled DPIF assuming
that the runtime CPU is capable of running AVX512 instructions:
$ ovs-appctl dpif-netdev/dpif-set dpif_avx512
A new configuration flag is added to allow selection of the
default DPIF. This is useful for running the unit-tests against
the available DPIF implementations, without modifying each unit test.
The design of the testing & validation for ISA optimized DPIF
implementations is based around the work already upstream for DPCLS.
Note however that a DPCLS lookup has no state or side-effects, allowing
the auto-validator implementation to perform multiple lookups and
provide consistent statistic counters.
The DPIF component does have state, so running two implementations in
parallel and comparing output is not a valid testing method, as there
are changes in DPIF statistic counters (side effects). As a result, the
DPIF is tested directly against the unit-tests.
Signed-off-by: Harry van Haaren
Signed-off-by: Cian Ferriter
---
v3:
- Reformat code to match OVS style
- Reformat comments to match OVS style
- Improve return values for dp_netdev_input_outer_avx512_probe(). Use
errno values and return 0 on success.
- Remove "TODO: call the dpif selector impl here, int ret, out param for
func ptr:"
- Remove "TODO make this register/selectable just like DPCLS"
---
acinclude.m4 | 15 +
configure.ac | 1 +
lib/automake.mk | 1 +
lib/dpif-netdev-avx512.c | 14 +
lib/dpif-netdev-private-dpif.c | 104 +++
lib/dpif-netdev-private-dpif.h | 31 -
lib/dpif-netdev-private-thread.h | 12 +---
lib/dpif-netdev.c| 84 +++--
8 files changed, 247 insertions(+), 15 deletions(-)
create mode 100644 lib/dpif-netdev-private-dpif.c
diff --git a/acinclude.m4 b/acinclude.m4
index 1460289ca..9a7cb8df0 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -30,6 +30,21 @@ AC_DEFUN([OVS_CHECK_DPCLS_AUTOVALIDATOR], [
fi
])
+dnl Set OVS DPIF default implementation at configure time for running the unit
+dnl tests on the whole codebase without modifying tests per DPIF impl
+AC_DEFUN([OVS_CHECK_DPIF_AVX512_DEFAULT], [
+ AC_ARG_ENABLE([dpif-default-avx512],
+[AC_HELP_STRING([--enable-dpif-default-avx512], [Enable DPIF
AVX512 implementation as default.])],
+[dpifavx512=yes],[dpifavx512=no])
+ AC_MSG_CHECKING([whether DPIF AVX512 is default implementation])
+ if test "$dpifavx512" != yes; then
+AC_MSG_RESULT([no])
+ else
+OVS_CFLAGS="$OVS_CFLAGS -DDPIF_AVX512_DEFAULT"
+AC_MSG_RESULT([yes])
+ fi
+])
+
dnl OVS_ENABLE_WERROR
AC_DEFUN([OVS_ENABLE_WERROR],
[AC_ARG_ENABLE(
diff --git a/configure.ac b/configure.ac
index 126a1d9d1..76b1e4fec 100644
--- a/configure.ac
+++ b/configure.ac
@@ -185,6 +185,7 @@ OVS_ENABLE_WERROR
OVS_ENABLE_SPARSE
OVS_CTAGS_IDENTIFIERS
OVS_CHECK_DPCLS_AUTOVALIDATOR
+OVS_CHECK_DPIF_AVX512_DEFAULT
OVS_CHECK_BINUTILS_AVX512
AC_ARG_VAR(KARCH, [Kernel Architecture String])
diff --git a/lib/automake.mk b/lib/automake.mk
index 650207940..2a41f7ab5 100644
--- a/lib/automake.mk
+++ b/lib/automake.mk
@@ -115,6 +115,7 @@ lib_libopenvswitch_la_SOURCES = \
lib/dpif-netdev.h \
lib/dpif-netdev-private-dfc.h \
lib/dpif-netdev-private-dpcls.h \
+ lib/dpif-netdev-private-dpif.c \
lib/dpif-netdev-private-dpif.h \
lib/dpif-netdev-private-flow.h \
lib/dpif-netdev-private-hwol.h \
diff --git a/lib/dpif-netdev-avx512.c b/lib/dpif-netdev-avx512.c
index ff756a203..2dee909a3 100644
--- a/lib/dpif-netdev-avx512.c
+++ b/lib/dpif-netdev-avx512.c
@@ -19,6 +19,7 @@
#if !defined(__CHECKER__)
#include
+#include
#include "dpif-netdev.h"
#include "dpif-netdev-perf.h"
@@ -44,6 +45,19 @@ struct pkt_flow_meta {
uint16_t tcp_flags;
};
+int32_t
+dp_netdev_input_outer_avx512_probe(void)
+{
+int avx512f_available = dpdk_get_cpu_has_isa("x86_64", "avx512f");
+int bmi2_available = dpdk_get_cpu_has_isa("x86_64", "bmi2");
+
+if (!avx512f_available || !bmi2_available) {
+return -ENOTSUP;
+}
+
+return 0;
+}
+
int32_t
dp_netdev_input_outer_avx512(struct dp_netdev_pmd_thread *pmd,
struct dp_packet_batch *packets,
diff --git a/lib/dpif-netdev-private-dpif.c b/lib/dpif-netdev-private-dpif.c
new file mode 100644
index 0..a27a1d752
--- /dev/null
+++ b/lib/dpif-netdev-private-dpif.c
@@ -0,0 +1,104 @@
+/*
+ * Copyright (c) 2020 Intel Corporation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the
