From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 68DBDA00C2; Wed, 22 Apr 2020 20:16:38 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 3D46B1D572; Wed, 22 Apr 2020 20:16:38 +0200 (CEST) Received: from mail-qk1-f194.google.com (mail-qk1-f194.google.com [209.85.222.194]) by dpdk.org (Postfix) with ESMTP id 861761D559 for ; Wed, 22 Apr 2020 20:16:36 +0200 (CEST) Received: by mail-qk1-f194.google.com with SMTP id b62so3442606qkf.6 for ; Wed, 22 Apr 2020 11:16:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=Lo8+d918gZimIDGjN/gkv+6HIWmTeGcYnnMcht/KXPo=; b=ozi34Tw/9EPk5TWfwL97SFeO4HDq4vWAM1CVGsaL912UC2BJauNe6U8268uDgVpn8e SRBPNn1PKaTsgSb6i6P0gaPBjwnKGaOC7dxtUC7WjEXhgiaOIhX5FlmpDBxM+FUz3SCS M0YmnGYzTkx64Hp1BZ+UgMIRifyxLmOF5Cwycd0kAWMp2CDIcAyT0vKEeVDpJulig5CS c7GwEyPywHMNUvKjP7sjbDe0q84vEItHzYPIgELLqXjeSKYB2LXcg4xqYsL4LXRpB0s0 qTmldCrD1FlU88HSkVmdV1G6QwApT2tAY0JlZvpZrV2cBzVyGSaS+NznTsf8BopNLcwV +oUw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-transfer-encoding; bh=Lo8+d918gZimIDGjN/gkv+6HIWmTeGcYnnMcht/KXPo=; b=A4ZWuPzZGeBMIYvLQArqNswBvX4103En+L+0rNRzxR7im0MzJgocdiLgBMEhFtWLoO MP6O3XMmbYYppGB1lj86BAlTHOqNzpfVAW0iEX0Y4g3EXjCVuhno4urVkEJTaBBmxSe4 DiA1IMEOkT7l6seJhWJ8dHs+yOXsClOSbaPvEfoj919N7+ZtAq9bmfyBDc3DNYIrM+PT e93bUlRECMIfT+dKTiRA0XAeRMQfb/Dt5oN7OaUkFf4SLL1W80Uu2JQmB9pUazGxg4iW 2DDR+QK/lUrSHj2F7GJORT9IKLW3C2cbbc79DqJecGft1SaZCehxurIqMWWXKKozh9i6 Resg== X-Gm-Message-State: AGi0Pua9JzqpSN8IXcz1E1VNDBU/4HJ+kpnYM3lHTMKNK+VglFJXUVaR 3axJbTDBBw1cEfyW5YVP8PdtCZnUTK0= X-Google-Smtp-Source: APiQypIAbApKBAz9+5FF8MPXaVoXGNTL6ERlkL8ITrFH9FRDbjW9KCNyYVJIwco/CWBn5SRPprmwjQ== X-Received: by 2002:a37:a049:: with SMTP id j70mr27140130qke.193.1587579395583; Wed, 22 Apr 2020 11:16:35 -0700 (PDT) Received: from localhost.localdomain ([168.121.99.161]) by smtp.gmail.com with ESMTPSA id d26sm4360227qkk.69.2020.04.22.11.16.33 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 22 Apr 2020 11:16:35 -0700 (PDT) From: Dan Gora To: dev@dpdk.org, Thomas Monjalon , =?UTF-8?q?Mattias=20R=C3=B6nnblom?= Cc: David Marchand , Jerin Jacob , Dan Gora Date: Wed, 22 Apr 2020 15:15:23 -0300 Message-Id: <20200422181524.18679-2-dg@adax.com> X-Mailer: git-send-email 2.24.1.425.g7034cd094b In-Reply-To: <20200422181524.18679-1-dg@adax.com> References: <20200421195446.1730-1-dg@adax.com> <20200422181524.18679-1-dg@adax.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: [dpdk-dev] [PATCH v3 1/2] eal: check for rdseed at run time for random seed X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Instead of enabling the rdseed instruction for the random number generator entropy source at compilation time, determine if the instruction can be used at run time. The DPDK build is updated to check that the compiler can generate the rdseed instruction even if the compilation platform does not natively support it. If so, the -mrdseed flag is explicitly added. This allows binaries compiled on systems which do not support the rdseed instruction to use the instruction if the execution platform supports it. At run-time on x86, __rte_random_initial_seed() will check for the availability of the rdseed instruction on the execution platform using rte_cpu_get_flag_enabled(). This allows binaries which were compiled on systems which support the rdseed instruction to run on x86 CPUs which do not support the rdseed instruction. RTE_CPUFLAG_RDSEED is removed from the list of RTE_COMPILE_TIME_CPUFLAGS which are checked in rte_eal_init() at run time because it is no longer required to match the compilation system. Signed-off-by: Dan Gora --- config/x86/meson.build | 11 ++++++++--- lib/librte_eal/common/rte_random.c | 19 +++++++++++-------- mk/rte.cpuflags.mk | 9 +++++++-- 3 files changed, 26 insertions(+), 13 deletions(-) diff --git a/config/x86/meson.build b/config/x86/meson.build index adc857ba2..9491fad3a 100644 --- a/config/x86/meson.build +++ b/config/x86/meson.build @@ -20,15 +20,20 @@ if cc.get_define('__SSE4_2__', args: machine_args) == '' machine_args += '-msse4' endif +# set -mrdseed if necessary so _rdseed32_step compiles if the +# compilation host does not support the RDSEED instruction. +if cc.get_define('__RDSEED__', args: machine_args) == '' and cc.has_argument('-mrdseed') + machine_args += '-mrdseed' + message('RDSEED not enabled by default, explicitly setting -mrdseed') +endif + base_flags = ['SSE', 'SSE2', 'SSE3','SSSE3', 'SSE4_1', 'SSE4_2'] foreach f:base_flags dpdk_conf.set('RTE_MACHINE_CPUFLAG_' + f, 1) compile_time_cpuflags += ['RTE_CPUFLAG_' + f] endforeach -optional_flags = ['AES', 'PCLMUL', - 'AVX', 'AVX2', 'AVX512F', - 'RDRND', 'RDSEED'] +optional_flags = ['AES', 'PCLMUL', 'AVX', 'AVX2', 'AVX512F', 'RDRND'] foreach f:optional_flags if cc.get_define('__@0@__'.format(f), args: machine_args) == '1' if f == 'PCLMUL' # special case flags with different defines diff --git a/lib/librte_eal/common/rte_random.c b/lib/librte_eal/common/rte_random.c index b7a089ac4..2c84c8527 100644 --- a/lib/librte_eal/common/rte_random.c +++ b/lib/librte_eal/common/rte_random.c @@ -2,7 +2,7 @@ * Copyright(c) 2019 Ericsson AB */ -#ifdef RTE_MACHINE_CPUFLAG_RDSEED +#if defined(RTE_ARCH_X86) #include #endif #include @@ -188,14 +188,17 @@ __rte_random_initial_seed(void) if (ge_rc == 0) return ge_seed; #endif -#ifdef RTE_MACHINE_CPUFLAG_RDSEED - unsigned int rdseed_low; - unsigned int rdseed_high; - +#if defined(RTE_ARCH_X86) /* first fallback: rdseed instruction, if available */ - if (_rdseed32_step(&rdseed_low) == 1 && - _rdseed32_step(&rdseed_high) == 1) - return (uint64_t)rdseed_low | ((uint64_t)rdseed_high << 32); + if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_RDSEED)) { + unsigned int rdseed_low; + unsigned int rdseed_high; + + if (_rdseed32_step(&rdseed_low) == 1 && + _rdseed32_step(&rdseed_high) == 1) + return (uint64_t)rdseed_low | + ((uint64_t)rdseed_high << 32); + } #endif /* second fallback: seed using rdtsc */ return rte_get_tsc_cycles(); diff --git a/mk/rte.cpuflags.mk b/mk/rte.cpuflags.mk index fa8753531..a114e9c02 100644 --- a/mk/rte.cpuflags.mk +++ b/mk/rte.cpuflags.mk @@ -51,8 +51,13 @@ ifneq ($(filter $(AUTO_CPUFLAGS),__RDRND__),) CPUFLAGS += RDRAND endif -ifneq ($(filter $(AUTO_CPUFLAGS),__RDSEED__),) -CPUFLAGS += RDSEED +ifeq ($(filter $(AUTO_CPUFLAGS),__RDSEED__),) +# If the native environment doesn't define __RDSEED__, see +# if the compiler supports -mrdseed. +RDSEED_CPUFLAGS := $(shell $(CC) $(MACHINE_CFLAGS) $(WERROR_FLAGS) $(EXTRA_CFLAGS) -mrdseed -dM -E - < /dev/null) +ifneq ($(filter $(RDSEED_CPUFLAGS),__RDSEED__),) +MACHINE_CFLAGS += -mrdseed +endif endif ifneq ($(filter $(AUTO_CPUFLAGS),__FSGSBASE__),) -- 2.24.1.425.g7034cd094b