eal/x86: check rdrand and rdseed

The meson build never checked for the presence of rdrand and rdseed
instructions, while make build never checked for rdseed. Ensure builds
always have the appropriate checks - and therefore defines - for these
instructions. For runtime, we also add in rdseed to the list of known
bits returned from cpuid() instruction, so we can confirm its presence at
application init time.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Tested-by: Mattias Rönnblom <mattias.ronnblom@ericsson.com>

config/x86/meson.build

@@ -29,11 +29,14 @@ foreach f:base_flags
 endforeach
 
 optional_flags = ['AES', 'PCLMUL',
-		'AVX', 'AVX2', 'AVX512F']
+		'AVX', 'AVX2', 'AVX512F',
+		'RDRND', 'RDSEED']
 foreach f:optional_flags
 	if cc.get_define('__@0@__'.format(f), args: machine_args) == '1'
 		if f == 'PCLMUL' # special case flags with different defines
 			f = 'PCLMULQDQ'
+		elif f == 'RDRND'
+			f = 'RDRAND'
 		endif
 		dpdk_conf.set('RTE_MACHINE_CPUFLAG_' + f, 1)
 		compile_time_cpuflags += ['RTE_CPUFLAG_' + f]

lib/librte_eal/common/arch/x86/rte_cpuflags.c

@@ -108,6 +108,7 @@ const struct feature_entry rte_cpu_feature_table[] = {
 	FEAT_DEF(INVPCID, 0x00000007, 0, RTE_REG_EBX, 10)
 	FEAT_DEF(RTM, 0x00000007, 0, RTE_REG_EBX, 11)
 	FEAT_DEF(AVX512F, 0x00000007, 0, RTE_REG_EBX, 16)
+	FEAT_DEF(RDSEED, 0x00000007, 0, RTE_REG_EBX, 18)
 
 	FEAT_DEF(LAHF_SAHF, 0x80000001, 0, RTE_REG_ECX,  0)
 	FEAT_DEF(LZCNT, 0x80000001, 0, RTE_REG_ECX,  4)

lib/librte_eal/common/include/arch/x86/rte_cpuflags.h

@@ -97,6 +97,7 @@ enum rte_cpu_flag_t {
 	RTE_CPUFLAG_INVPCID,                /**< INVPCID */
 	RTE_CPUFLAG_RTM,                    /**< Transactional memory */
 	RTE_CPUFLAG_AVX512F,                /**< AVX512F */
+	RTE_CPUFLAG_RDSEED,                 /**< RDSEED instruction */
 
 	/* (EAX 80000001h) ECX features */
 	RTE_CPUFLAG_LAHF_SAHF,              /**< LAHF_SAHF */

mk/rte.cpuflags.mk

@@ -51,6 +51,10 @@ ifneq ($(filter $(AUTO_CPUFLAGS),__RDRND__),)
 CPUFLAGS += RDRAND
 endif
 
+ifneq ($(filter $(AUTO_CPUFLAGS),__RDSEED__),)
+CPUFLAGS += RDSEED
+endif
+
 ifneq ($(filter $(AUTO_CPUFLAGS),__FSGSBASE__),)
 CPUFLAGS += FSGSBASE
 endif