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 8177BA00C2; Thu, 23 Apr 2020 01:44:24 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 793571D166; Thu, 23 Apr 2020 01:44:19 +0200 (CEST) Received: from mail-qk1-f196.google.com (mail-qk1-f196.google.com [209.85.222.196]) by dpdk.org (Postfix) with ESMTP id 385B81D159 for ; Thu, 23 Apr 2020 01:44:18 +0200 (CEST) Received: by mail-qk1-f196.google.com with SMTP id m67so4454391qke.12 for ; Wed, 22 Apr 2020 16:44:18 -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=HFruzfxmf66vHxZnjxTFnXlrseYbcFRXWZFgCVMRsC3HvlEQZ0kkMo3I8SNEKlmrVy gMTTeYR85YPVy+0p9bYlqO1fFu/1V378yTs7WMxJ0ORvy3RHRYY9mwZkpakTgA6M10Ft Gj83li5T3tsQmJ8j1dwfidYMWZdI5eTjq1Lg4KQipiQsf20DRt1Qq4NOkv1OGp+Yv/VL 1DWHGjXaU4epA4tdgoQdfUkKK+v6ceRhk9ux9nMglHBIEPV5LifAkwbJtc19/idbD/uL VSEuqxc6ThVJs1erWAQ9pk0WqnqriGWj5Wy9IkVYlONInbU+LIIxwNjkoLm3kX9RgAUQ QZYA== 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=e1KgWvh6Kog4jXjvvL0VED9YSVi7iDN3CuTP+M3elreryJJ9c2q/cakt5wGfIfzbun eYqQl0O5TlzbDe9FGq986DY45sx5Q+kHF8Nf7u6l5gOwOuSWYLdOX4eNSpuxqrVEP+PV B2sXhPZoBtiJjnXeyDihnhdypRwbOQA0CZpCMXkOXcFAHaQqlgl+Ay7EZPS+gcDszBkc yXfGtww3xEiG09XP1ybMxfLo0QhN+FgHUnfzCgN+ng2nqfOmepIPsBe39prR1Nl88B9M vn9s20sq1GDR7ihzXGZDOgxfdnU96nTippaupbNdd6yjwJTqr3aWXA6fwmAKmJSfjj0a t79A== X-Gm-Message-State: AGi0PubaAmrMPmkF9eC2G+81Z9oZhHnGraymWBPxngjoOiKkjA6iWxFz uRF3fUVOiaYMdqUDefl+dDde4DDNUbQ= X-Google-Smtp-Source: APiQypL+ilfjgTGQKbTvboOJraGU4YqJJPOGZtUnwuCqFDlyzpMIgcp5XOsjStKdPmxbOC/xkNTgxQ== X-Received: by 2002:a37:a6d4:: with SMTP id p203mr781548qke.201.1587599057170; Wed, 22 Apr 2020 16:44:17 -0700 (PDT) Received: from localhost.localdomain ([168.121.99.161]) by smtp.gmail.com with ESMTPSA id t15sm614263qtc.64.2020.04.22.16.44.15 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 22 Apr 2020 16:44:16 -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 20:42:53 -0300 Message-Id: <20200422234255.7066-2-dg@adax.com> X-Mailer: git-send-email 2.24.1.425.g7034cd094b In-Reply-To: <20200422234255.7066-1-dg@adax.com> References: <20200421195446.1730-1-dg@adax.com> <20200422234255.7066-1-dg@adax.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: [dpdk-dev] [PATCH v4 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