ARM support for BESS

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "deps/sse2neon"]
+	path = deps/sse2neon
+	url = https://github.com/DLTcollab/sse2neon

CONTRIBUTING.md

@@ -64,3 +64,4 @@ Please add your name to the end of this file and include this file to the PR, un
 * Brent Stephens
 * M. Asim Jamshed
 * Yan Grunenberger
+* Md Ashfaqur Rahaman

build.py

@@ -41,6 +41,7 @@
 import subprocess
 import textwrap
 import argparse
+import platform
 
 
 def cmd(cmd, quiet=False, shell=False):
@@ -90,7 +91,14 @@ def cmd(cmd, quiet=False, shell=False):
 
 DPDK_URL = 'https://fast.dpdk.org/rel'
 DPDK_VER = 'dpdk-19.11.4'
-DPDK_TARGET = 'x86_64-native-linuxapp-gcc'
+
+if platform.uname().machine == 'x86_64':
+    DPDK_TARGET = 'x86_64-native-linuxapp-gcc'
+elif platform.uname().machine == 'aarch64':
+    DPDK_TARGET = 'arm64-armv8a-linux-gcc'
+else:
+    print("Unsupported platform")
+    sys.exit(1)
 
 kernel_release = cmd('uname -r', quiet=True).strip()
 
@@ -299,10 +307,10 @@ def configure_dpdk():
     check_mlx()
     generate_dpdk_extra_mk()
 
-    arch = os.getenv('CPU')
-    if arch:
-        print(' - Building DPDK with -march=%s' % arch)
-        set_config(DPDK_CONFIG, "CONFIG_RTE_MACHINE", arch)
+    arch = platform.uname().machine
+    if arch == 'aarch64':
+        print(' - Building DPDK with -march=%s' % 'armv8-a')
+        set_config(DPDK_CONFIG, "CONFIG_RTE_MACHINE", 'armv8-a')
 
 
 def makeflags():

core/Makefile

@@ -60,9 +60,18 @@ ifeq "$(CXXCOMPILER)" "g++"
 endif
 
 HAS_PKG_CONFIG := $(shell command -v $(PKG_CONFIG) 2>&1 >/dev/null && echo yes || echo no)
+ARCH := $(shell uname -m)
 
 RTE_SDK ?= $(abspath ../deps/dpdk-19.11.4)
-RTE_TARGET ?= $(shell uname -m)-native-linuxapp-gcc
+
+ifeq ($(ARCH),x86_64)
+  RTE_TARGET ?= $(shell uname -m)-native-linuxapp-gcc
+else ifeq ($(ARCH),aarch64)
+  RTE_TARGET ?= arm64-armv8a-linux-gcc
+else
+  $(error Unsupported architecture)
+endif
+
 DPDK_LIB ?= dpdk
 
 ifneq ($(wildcard $(RTE_SDK)/$(RTE_TARGET)/*),)
@@ -76,6 +85,10 @@ else ifneq ($(MAKECMDGOALS),clean)
   $(error DPDK is not available. Make sure $(abspath $(RTE_SDK)) is available and built)
 endif
 
+# Library for translating Intel SSE intrinsics
+# to ARM64 NEON
+SSE2NEON_DIR ?= $(abspath ../deps/sse2neon)
+
 # We always want these libraries to be dynamically linked even when the
 # user requests a static build.
 ALWAYS_DYN_LIBS := -lpthread -ldl
@@ -108,9 +121,16 @@ endif
 # these headers.  Should fix the warnings.  Using -isystem also disables
 # -MMD dependency recording (should we use -MD?).
 COREDIR := $(abspath .)
-CPU ?= native
+ifeq ($(ARCH),x86_64)
+  CPU ?= native
+else ifeq ($(ARCH),aarch64)
+  CPU ?= armv8-a+fp+simd
+else
+  $(error Unsupported architecture)
+endif
 CXXFLAGS += -std=c++17 -g3 -ggdb3 -march=$(CPU) \
             -isystem $(DPDK_INC_DIR) -isystem $(COREDIR) \
+            -isystem $(SSE2NEON_DIR) \
             -isystem $(dir $<).. -isystem $(COREDIR)/modules \
             -D_GNU_SOURCE \
             -Werror -Wall -Wextra -Wcast-align -Wno-error=deprecated-declarations \
@@ -133,6 +153,10 @@ ifeq "$(shell expr $(CXXCOMPILER) = g++)" "1"
   CXXFLAGS += -fno-gnu-unique
 endif
 
+ifeq ($(ARCH),aarch64)
+  CXXFLAGS += -DRTE_FORCE_INTRINSICS
+endif
+
 LDFLAGS += -rdynamic -L$(DPDK_LIB_DIR) -Wl,-rpath=$(DPDK_LIB_DIR) -pthread
 ifdef BESS_LINK_DYNAMIC
   LIBS_ALL_SHARED = -Wl,-call_shared

core/debug.cc

@@ -410,7 +410,16 @@ static bool SkipSymbol(char *symbol) {
 // TODO: Only use async-signal-safe operations in the signal handler.
 static void TrapHandler(int sig_num, siginfo_t *info, void *ucontext) {
   std::ostringstream oops;
+
+#if (__i386 || __x86_64)
   auto *uc = static_cast<ucontext_t *>(ucontext);
+#elif __aarch64__
+  // unused parameter
+  (void)ucontext;
+#else
+#error Unsupported architecture
+#endif
+
   bool is_fatal = (sig_num != SIGUSR1);
   static volatile bool already_trapped = false;
 
@@ -422,8 +431,10 @@ static void TrapHandler(int sig_num, siginfo_t *info, void *ucontext) {
   trap_ip = reinterpret_cast<void *>(uc->uc_mcontext.gregs[REG_EIP]);
 #elif __x86_64
   trap_ip = reinterpret_cast<void *>(uc->uc_mcontext.gregs[REG_RIP]);
+#elif __aarch64__
+  trap_ip = nullptr;
 #else
-#error neither x86 or x86-64
+#error Unsupported architecture
 #endif
 
   if (is_fatal) {

core/gate_hooks/pcapng.cc

@@ -62,7 +62,7 @@ T PadSize(T a, T b) {
 
 // Return the single hex digit representing `nibble`.  If it cannot be
 // represented, return the char 'X'.
-char NibbleToHD(char nibble) {
+char NibbleToHD(signed char nibble) {
   if (nibble >= 0 && nibble <= 9) {
     return nibble + '0';
   } else if (nibble >= 10 && nibble <= 15) {

core/kmod/llring.h

@@ -149,7 +149,13 @@ typedef uint64_t phys_addr_t;
 #define llring_likely(x) __builtin_expect(!!(x), 1)
 #define llring_unlikely(x) __builtin_expect(!!(x), 0)
 
+#if __x86_64
 #include <emmintrin.h>
+#elif __aarch64__
+#include <sse2neon.h>
+#else
+#error Unsupported architecture
+#endif
 
 static inline void llring_pause(void) { _mm_pause(); }
 

core/modules/ip_lookup.cc

@@ -39,7 +39,13 @@
 #include "../utils/format.h"
 #include "../utils/ip.h"
 
+#if __x86_64
 #define VECTOR_OPTIMIZATION 1
+#elif __aarch64__
+#define VECTOR_OPTIMIZATION 0
+#else
+#error Unsupported architecture
+#endif
 
 static inline int is_valid_gate(gate_idx_t gate) {
   return (gate < MAX_GATES || gate == DROP_GATE);
@@ -84,7 +90,7 @@ void IPLookup::ProcessBatch(Context *ctx, bess::PacketBatch *batch) {
   gate_idx_t default_gate = default_gate_;
 
   int cnt = batch->cnt();
-  int i;
+  int i = 0;
 
 #if VECTOR_OPTIMIZATION
   // Convert endianness for four addresses at the same time

core/modules/set_metadata.cc

@@ -28,7 +28,13 @@
 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 // POSSIBILITY OF SUCH DAMAGE.
 
+#if __x86_64
 #include <x86intrin.h>
+#elif __aarch64__
+#include <sse2neon.h>
+#else
+#error Unsupported architecture
+#endif
 
 #include <cmath>
 

core/utils/bits.h

@@ -31,7 +31,13 @@
 #define BESS_UTILS_BITS_H_
 
 #include <glog/logging.h>
+#if __x86_64
 #include <x86intrin.h>
+#elif __aarch64__
+#include <sse2neon.h>
+#else
+#error Unsupported architecture
+#endif
 
 #include <algorithm>