New upstream version 18.08upstream/18.08

Change-Id: I32fdf5e5016556d9c0a6d88ddaf1fc468961790a
Signed-off-by: Luca Boccassi <luca.boccassi@gmail.com>

1 files changed, 84 insertions, 0 deletions

diff --git a/lib/librte_eal/linuxapp/eal/eal_cpuflags.c b/lib/librte_eal/linuxapp/eal/eal_cpuflags.c
new file mode 100644
index 00000000..d38296e1
--- /dev/null
+++ b/lib/librte_eal/linuxapp/eal/eal_cpuflags.c
@@ -0,0 +1,84 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright 2018 Red Hat, Inc.
+ */
+
+#include <elf.h>
+#include <fcntl.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#if defined(__GLIBC__) && defined(__GLIBC_PREREQ)
+#if __GLIBC_PREREQ(2, 16)
+#include <sys/auxv.h>
+#define HAS_AUXV 1
+#endif
+#endif
+
+#include <rte_cpuflags.h>
+
+#ifndef HAS_AUXV
+static unsigned long
+getauxval(unsigned long type __rte_unused)
+{
+	errno = ENOTSUP;
+	return 0;
+}
+#endif
+
+#ifdef RTE_ARCH_64
+typedef Elf64_auxv_t Internal_Elfx_auxv_t;
+#else
+typedef Elf32_auxv_t Internal_Elfx_auxv_t;
+#endif
+
+/**
+ * Provides a method for retrieving values from the auxiliary vector and
+ * possibly running a string comparison.
+ *
+ * @return Always returns a result.  When the result is 0, check errno
+ * to see if an error occurred during processing.
+ */
+static unsigned long
+_rte_cpu_getauxval(unsigned long type, const char *str)
+{
+	unsigned long val;
+
+	errno = 0;
+	val = getauxval(type);
+
+	if (!val && (errno == ENOTSUP || errno == ENOENT)) {
+		int auxv_fd = open("/proc/self/auxv", O_RDONLY);
+		Internal_Elfx_auxv_t auxv;
+
+		if (auxv_fd == -1)
+			return 0;
+
+		errno = ENOENT;
+		while (read(auxv_fd, &auxv, sizeof(auxv)) == sizeof(auxv)) {
+			if (auxv.a_type == type) {
+				errno = 0;
+				val = auxv.a_un.a_val;
+				if (str)
+					val = strcmp((const char *)val, str);
+				break;
+			}
+		}
+		close(auxv_fd);
+	}
+
+	return val;
+}
+
+unsigned long
+rte_cpu_getauxval(unsigned long type)
+{
+	return _rte_cpu_getauxval(type, NULL);
+}
+
+int
+rte_cpu_strcmp_auxval(unsigned long type, const char *str)
+{
+	return _rte_cpu_getauxval(type, str);
+}