From patchwork Wed Jun 5 10:43:55 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Mattias_R=C3=B6nnblom?= X-Patchwork-Id: 54412 X-Patchwork-Delegate: thomas@monjalon.net Return-Path: X-Original-To: patchwork@dpdk.org Delivered-To: patchwork@dpdk.org Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id C1C411BABD; Wed, 5 Jun 2019 12:44:39 +0200 (CEST) Received: from sessmg22.ericsson.net (sessmg22.ericsson.net [193.180.251.58]) by dpdk.org (Postfix) with ESMTP id 43BF01BA85 for ; Wed, 5 Jun 2019 12:44:36 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; d=ericsson.com; s=mailgw201801; c=relaxed/relaxed; q=dns/txt; i=@ericsson.com; t=1559731476; x=1562323476; h=From:Sender:Reply-To:Subject:Date:Message-ID:To:CC:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=WBL9R248asGlQ4P1zIGbaAS1mMbt45m7vc7GQMANGcM=; b=b7qXIwQyXW5eihox7bFdurum12EA6qeonT/5PMvIi4BbtrzSO2Er92wIfvYi4WOU Vg+nncc7COBBTccqKRMBnzlk8UUgRXqhX/NbWCE1bTEvbVjBwZ24TKi5Qm0gtqjT /sT4Iu+yS9B+3QsEEAJ63QsKwGaHFN3pdJo2JrtfMZY=; X-AuditID: c1b4fb3a-709ff7000000189f-45-5cf79d144e4f Received: from ESESBMB503.ericsson.se (Unknown_Domain [153.88.183.116]) by sessmg22.ericsson.net (Symantec Mail Security) with SMTP id F6.FD.06303.41D97FC5; Wed, 5 Jun 2019 12:44:36 +0200 (CEST) Received: from ESESSMB504.ericsson.se (153.88.183.165) by ESESBMB503.ericsson.se (153.88.183.170) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5; Wed, 5 Jun 2019 12:44:26 +0200 Received: from selio1a020.lmera.ericsson.se (153.88.183.153) by smtp.internal.ericsson.com (153.88.183.192) with Microsoft SMTP Server id 15.1.1713.5 via Frontend Transport; Wed, 5 Jun 2019 12:44:26 +0200 Received: from breslau.lmera.ericsson.se (breslau.lmera.ericsson.se [150.132.109.241]) by selio1a020.lmera.ericsson.se (8.15.1+Sun/8.15.1) with ESMTP id x55AiQRB025408; Wed, 5 Jun 2019 12:44:26 +0200 (CEST) From: =?utf-8?q?Mattias_R=C3=B6nnblom?= To: CC: , , , , =?utf-8?q?Mattias_R=C3=B6nnblom?= Date: Wed, 5 Jun 2019 12:43:55 +0200 Message-ID: <20190605104400.24484-2-mattias.ronnblom@ericsson.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190605104400.24484-1-mattias.ronnblom@ericsson.com> References: <20190516203529.GA642@bricha3-MOBL.ger.corp.intel.com> <20190605104400.24484-1-mattias.ronnblom@ericsson.com> MIME-Version: 1.0 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrDLMWRmVeSWpSXmKPExsUyM2J7ia7I3O8xBjt+s1ncWGVvsX1FF5vF u0/bmSxuNZ9ks1h8R86B1ePXgqWsHov3vGTy6Dk5j8nj/b6rbB5Xvq9mDGCN4rJJSc3JLEst 0rdL4Mp40PCVraDNs2L/wQPsDYw3bLoYOTkkBEwk9i+bzdrFyMUhJHCUUeLpxFNMEM5XRolb p3czQjgXGCUer1vNDuFcYpToXzSVEaSfTcBTYvK7bhYQW0RASGLpx8tgRcwCexklXq2bB5YQ FgiSeHX+GRuIzSKgIrHz4G2wOK+Ak8Tun3sZIQ6Rl1i94QAziM0p4CzxePp+JhBbSKBaYsLb ZiaIekGJkzOfgPUyC2hKtG7/zQ5hy0s0b53NDFGvJXF/yRfmCYxCs5C0zELSMgtJywJG5lWM osWpxcW56UZGeqlFmcnFxfl5enmpJZsYgXFwcMtvqx2MB587HmIU4GBU4uG91vs9Rog1say4 MvcQowQHs5IIb+LtLzFCvCmJlVWpRfnxRaU5qcWHGKU5WJTEeaNX74kREkhPLEnNTk0tSC2C yTJxcEo1MC64uU2/YyYnp2qPR3BKz/MJcuKbF4i6cU5t+bIhgfvAQcsZ89q8Hc4LRv4WTdvx PnEKu3w65y//MKutE5R2ff/kPyktXoRzx+2mmgmzLlxl+6Q753ar99/9UwTqt7gbWpTkv1i/ kC9gs9rCD+kKlTsVGr2vL15j88brVIwgN1v8ukj/6pk3FyixFGckGmoxFxUnAgD5N4/lfwIA AA== Subject: [dpdk-dev] [PATCH v3 1/6] eal: replace libc-based random number generation with LFSR 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" This commit replaces rte_rand()'s use of lrand48() with a DPDK-native combined Linear Feedback Shift Register (LFSR) (also known as Tausworthe) pseudo-random number generator. This generator is faster and produces better-quality random numbers than the linear congruential generator (LCG) of lib's lrand48(). The implementation, as opposed to lrand48(), is multi-thread safe in regards to concurrent rte_rand() calls from different lcore threads. A LCG is still used, but only to seed the five per-lcore LFSR sequences. In addition, this patch also addresses the issue of the legacy implementation only producing 62 bits of pseudo randomness, while the API requires all 64 bits to be random. This pseudo-random number generator is not cryptographically secure - just like lrand48(). Bugzilla ID: 114 Bugzilla ID: 276 Signed-off-by: Mattias Rönnblom Acked-by: Bruce Richardson --- lib/librte_eal/common/include/rte_random.h | 29 ++--- lib/librte_eal/common/meson.build | 1 + lib/librte_eal/common/rte_random.c | 139 +++++++++++++++++++++ lib/librte_eal/freebsd/eal/Makefile | 1 + lib/librte_eal/freebsd/eal/eal.c | 2 - lib/librte_eal/linux/eal/Makefile | 1 + lib/librte_eal/linux/eal/eal.c | 2 - lib/librte_eal/rte_eal_version.map | 2 + 8 files changed, 155 insertions(+), 22 deletions(-) create mode 100644 lib/librte_eal/common/rte_random.c diff --git a/lib/librte_eal/common/include/rte_random.h b/lib/librte_eal/common/include/rte_random.h index b2ca1c209..66dfe8ae7 100644 --- a/lib/librte_eal/common/include/rte_random.h +++ b/lib/librte_eal/common/include/rte_random.h @@ -16,7 +16,6 @@ extern "C" { #endif #include -#include /** * Seed the pseudo-random generator. @@ -25,34 +24,28 @@ extern "C" { * value. It may need to be re-seeded by the user with a real random * value. * + * This function is not multi-thread safe in regards to other + * rte_srand() calls, nor is it in relation to concurrent rte_rand() + * calls. + * * @param seedval * The value of the seed. */ -static inline void -rte_srand(uint64_t seedval) -{ - srand48((long)seedval); -} +void +rte_srand(uint64_t seedval); /** * Get a pseudo-random value. * - * This function generates pseudo-random numbers using the linear - * congruential algorithm and 48-bit integer arithmetic, called twice - * to generate a 64-bit value. + * The generator is not cryptographically secure. + * + * If called from lcore threads, this function is thread-safe. * * @return * A pseudo-random value between 0 and (1<<64)-1. */ -static inline uint64_t -rte_rand(void) -{ - uint64_t val; - val = (uint64_t)lrand48(); - val <<= 32; - val += (uint64_t)lrand48(); - return val; -} +uint64_t +rte_rand(void); #ifdef __cplusplus } diff --git a/lib/librte_eal/common/meson.build b/lib/librte_eal/common/meson.build index 0670e4102..bafd23207 100644 --- a/lib/librte_eal/common/meson.build +++ b/lib/librte_eal/common/meson.build @@ -35,6 +35,7 @@ common_sources = files( 'rte_keepalive.c', 'rte_malloc.c', 'rte_option.c', + 'rte_random.c', 'rte_reciprocal.c', 'rte_service.c' ) diff --git a/lib/librte_eal/common/rte_random.c b/lib/librte_eal/common/rte_random.c new file mode 100644 index 000000000..4d3cf5226 --- /dev/null +++ b/lib/librte_eal/common/rte_random.c @@ -0,0 +1,139 @@ +/* SPDX-License-Identifier: BSD-3-Clause + * Copyright(c) 2019 Ericsson AB + */ + +#include + +#include +#include +#include +#include +#include +#include + +struct rte_rand_state { + uint64_t z1; + uint64_t z2; + uint64_t z3; + uint64_t z4; + uint64_t z5; +} __rte_cache_aligned; + +static struct rte_rand_state rand_states[RTE_MAX_LCORE]; + +static uint32_t +__rte_rand_lcg32(uint32_t *seed) +{ + *seed = 1103515245U * *seed + 12345U; + + return *seed; +} + +static uint64_t +__rte_rand_lcg64(uint32_t *seed) +{ + uint64_t low; + uint64_t high; + + /* A 64-bit LCG would have been much cleaner, but good + * multiplier/increments for such seem hard to come by. + */ + + low = __rte_rand_lcg32(seed); + high = __rte_rand_lcg32(seed); + + return low | (high << 32); +} + +static uint64_t +__rte_rand_lfsr258_gen_seed(uint32_t *seed, uint64_t min_value) +{ + uint64_t res; + + res = __rte_rand_lcg64(seed); + + if (res < min_value) + res += min_value; + + return res; +} + +static void +__rte_srand_lfsr258(uint64_t seed, struct rte_rand_state *state) +{ + uint32_t lcg_seed; + + lcg_seed = (uint32_t)(seed ^ (seed >> 32)); + + state->z1 = __rte_rand_lfsr258_gen_seed(&lcg_seed, 2UL); + state->z2 = __rte_rand_lfsr258_gen_seed(&lcg_seed, 512UL); + state->z3 = __rte_rand_lfsr258_gen_seed(&lcg_seed, 4096UL); + state->z4 = __rte_rand_lfsr258_gen_seed(&lcg_seed, 131072UL); + state->z5 = __rte_rand_lfsr258_gen_seed(&lcg_seed, 8388608UL); +} + +void +rte_srand(uint64_t seed) +{ + unsigned int lcore_id; + + /* add lcore_id to seed to avoid having the same sequence */ + for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id++) + __rte_srand_lfsr258(seed + lcore_id, &rand_states[lcore_id]); +} + +static __rte_always_inline uint64_t +__rte_rand_lfsr258_comp(uint64_t z, uint64_t a, uint64_t b, uint64_t c, + uint64_t d) +{ + return ((z & c) << d) ^ (((z << a) ^ z) >> b); +} + +/* Based on L’Ecuyer, P.: Tables of maximally equidistributed combined + * LFSR generators. + */ + +static __rte_always_inline uint64_t +__rte_rand_lfsr258(struct rte_rand_state *state) +{ + state->z1 = __rte_rand_lfsr258_comp(state->z1, 1UL, 53UL, + 18446744073709551614UL, 10UL); + state->z2 = __rte_rand_lfsr258_comp(state->z2, 24UL, 50UL, + 18446744073709551104UL, 5UL); + state->z3 = __rte_rand_lfsr258_comp(state->z3, 3UL, 23UL, + 18446744073709547520UL, 29UL); + state->z4 = __rte_rand_lfsr258_comp(state->z4, 5UL, 24UL, + 18446744073709420544UL, 23UL); + state->z5 = __rte_rand_lfsr258_comp(state->z5, 3UL, 33UL, + 18446744073701163008UL, 8UL); + + return state->z1 ^ state->z2 ^ state->z3 ^ state->z4 ^ state->z5; +} + +static __rte_always_inline +struct rte_rand_state *__rte_rand_get_state(void) +{ + unsigned int lcore_id; + + lcore_id = rte_lcore_id(); + + if (unlikely(lcore_id == LCORE_ID_ANY)) + lcore_id = rte_get_master_lcore(); + + return &rand_states[lcore_id]; +} + +uint64_t +rte_rand(void) +{ + struct rte_rand_state *state; + + state = __rte_rand_get_state(); + + return __rte_rand_lfsr258(state); +} + +RTE_INIT(rte_rand_init) +{ + rte_srand(rte_get_timer_cycles()); +} diff --git a/lib/librte_eal/freebsd/eal/Makefile b/lib/librte_eal/freebsd/eal/Makefile index 19854ee2c..ca616c480 100644 --- a/lib/librte_eal/freebsd/eal/Makefile +++ b/lib/librte_eal/freebsd/eal/Makefile @@ -69,6 +69,7 @@ SRCS-$(CONFIG_RTE_EXEC_ENV_FREEBSD) += malloc_mp.c SRCS-$(CONFIG_RTE_EXEC_ENV_FREEBSD) += rte_keepalive.c SRCS-$(CONFIG_RTE_EXEC_ENV_FREEBSD) += rte_option.c SRCS-$(CONFIG_RTE_EXEC_ENV_FREEBSD) += rte_service.c +SRCS-$(CONFIG_RTE_EXEC_ENV_FREEBSD) += rte_random.c SRCS-$(CONFIG_RTE_EXEC_ENV_FREEBSD) += rte_reciprocal.c # from arch dir diff --git a/lib/librte_eal/freebsd/eal/eal.c b/lib/librte_eal/freebsd/eal/eal.c index c6ac9028f..5d43310b3 100644 --- a/lib/librte_eal/freebsd/eal/eal.c +++ b/lib/librte_eal/freebsd/eal/eal.c @@ -727,8 +727,6 @@ rte_eal_init(int argc, char **argv) #endif } - rte_srand(rte_rdtsc()); - /* in secondary processes, memory init may allocate additional fbarrays * not present in primary processes, so to avoid any potential issues, * initialize memzones first. diff --git a/lib/librte_eal/linux/eal/Makefile b/lib/librte_eal/linux/eal/Makefile index 6e5261152..729795a10 100644 --- a/lib/librte_eal/linux/eal/Makefile +++ b/lib/librte_eal/linux/eal/Makefile @@ -77,6 +77,7 @@ SRCS-$(CONFIG_RTE_EXEC_ENV_LINUX) += malloc_mp.c SRCS-$(CONFIG_RTE_EXEC_ENV_LINUX) += rte_keepalive.c SRCS-$(CONFIG_RTE_EXEC_ENV_LINUX) += rte_option.c SRCS-$(CONFIG_RTE_EXEC_ENV_LINUX) += rte_service.c +SRCS-$(CONFIG_RTE_EXEC_ENV_LINUX) += rte_random.c SRCS-$(CONFIG_RTE_EXEC_ENV_LINUX) += rte_reciprocal.c # from arch dir diff --git a/lib/librte_eal/linux/eal/eal.c b/lib/librte_eal/linux/eal/eal.c index 161399619..d6bf0e89e 100644 --- a/lib/librte_eal/linux/eal/eal.c +++ b/lib/librte_eal/linux/eal/eal.c @@ -1083,8 +1083,6 @@ rte_eal_init(int argc, char **argv) #endif } - rte_srand(rte_rdtsc()); - if (rte_eal_log_init(logid, internal_config.syslog_facility) < 0) { rte_eal_init_alert("Cannot init logging."); rte_errno = ENOMEM; diff --git a/lib/librte_eal/rte_eal_version.map b/lib/librte_eal/rte_eal_version.map index 824edf0ff..20c1a9018 100644 --- a/lib/librte_eal/rte_eal_version.map +++ b/lib/librte_eal/rte_eal_version.map @@ -292,6 +292,8 @@ DPDK_19.08 { rte_lcore_index; rte_lcore_to_socket_id; + rte_rand; + rte_srand; } DPDK_19.05;