From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by dpdk.space (Postfix) with ESMTP id 7BC58A00E6 for ; Thu, 16 May 2019 19:55:41 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 571895F2A; Thu, 16 May 2019 19:55:26 +0200 (CEST) Received: from sessmg23.ericsson.net (sessmg23.ericsson.net [193.180.251.45]) by dpdk.org (Postfix) with ESMTP id EF4365B20 for ; Thu, 16 May 2019 19:55:19 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; d=ericsson.com; s=mailgw201801; c=relaxed/relaxed; q=dns/txt; i=@ericsson.com; t=1558029318; x=1560621318; 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=d8IrLP7hWL5S+xfzhDw/zKwOPIKdITQcZEqq2N7axeU=; b=SJQzs8BVEX3R8pR4ysH2SVaQp01xilQ6gflxIS/D3bCxSnUGAtK5xVQFuILIx837 L6MBdQLFJMBPJmNGpcOe4/4YdU/8nAbjPhIgbWccyWLgfOzNWR/O3dzyTBAgRuI+ wz8UjGEEVkBmlYI5mWlPyecXpzXBmM2Lv/P1bbzsso8=; X-AuditID: c1b4fb2d-17dff70000001a6d-6a-5cdda4068800 Received: from ESESSMB501.ericsson.se (Unknown_Domain [153.88.183.119]) by sessmg23.ericsson.net (Symantec Mail Security) with SMTP id 78.27.06765.604ADDC5; Thu, 16 May 2019 19:55:18 +0200 (CEST) Received: from ESESSMB502.ericsson.se (153.88.183.163) by ESESSMB501.ericsson.se (153.88.183.162) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1713.5; Thu, 16 May 2019 19:55:18 +0200 Received: from selio1a020.lmera.ericsson.se (153.88.183.153) by smtp.internal.ericsson.com (153.88.183.190) with Microsoft SMTP Server id 15.1.1713.5 via Frontend Transport; Thu, 16 May 2019 19:55:18 +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 x4GHtHct023701; Thu, 16 May 2019 19:55:18 +0200 (CEST) From: =?UTF-8?q?Mattias=20R=C3=B6nnblom?= To: CC: , , =?UTF-8?q?Mattias=20R=C3=B6nnblom?= Date: Thu, 16 May 2019 19:55:05 +0200 Message-ID: <20190516175510.27154-2-mattias.ronnblom@ericsson.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190516175510.27154-1-mattias.ronnblom@ericsson.com> References: <20190514092046.30808-1-mattias.ronnblom@ericsson.com> <20190516175510.27154-1-mattias.ronnblom@ericsson.com> MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFrrOLMWRmVeSWpSXmKPExsUyM2J7uS7bkrsxBlMuWFvcWGVv8e7TdiaL xXfkHJg9fi1YyuqxeM9LJo+ek/OYApijuGxSUnMyy1KL9O0SuDLWvZ3NXvDeo+LwApEGxu02 XYycHBICJhLzzq1k62Lk4hASOMoocW5tBxOE841RYv6Fs6wQzkVGidvzFrFAOJcZJc7Pb2QH 6WcT8JSY/K6bBcQWERCSWPrxMjtIEbNAK6PEjoeNrCAJYYEgieeP74LZLAKqEqtXr2QEsXkF nCSO9XxngzhEXmL1hgPMIDangLPE1fMHwOqFBKolfnatYYKoF5Q4OfMJ2DJmAU2J1u2/2SFs eYnmrbOZIeq1JO4v+cI8gVFoFpKWWUhaZiFpWcDIvIpRtDi1uDg33chYL7UoM7m4OD9PLy+1 ZBMjMLgPbvmtu4Nx9WvHQ4wCHIxKPLzf59yNEWJNLCuuzD3EKMHBrCTCu+H97Rgh3pTEyqrU ovz4otKc1OJDjNIcLErivNGr98QICaQnlqRmp6YWpBbBZJk4OKUaGDt6nW7MPXN3nS/blPfh PNfSEk+ePP+13EOn1mjeVo1/HxZVny9JT1UJVjrRdnbj0rVhE9uS7DO7+vouuy8TFvVimc+z w/jkh1cqEYErI/+c+JVpe/poeOhjpT4d5cZFBusezWh/YxHImpzOJOTNI/N/Sm9MplkFlyHr 7Qh9mbiT6pIs3dp3lViKMxINtZiLihMBOkCBZWoCAAA= Subject: [dpdk-dev] [PATCH v2 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 --- 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 | 8 ++ 8 files changed, 161 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 245493461..e615d7cb9 100644 --- a/lib/librte_eal/rte_eal_version.map +++ b/lib/librte_eal/rte_eal_version.map @@ -287,6 +287,14 @@ DPDK_19.05 { } DPDK_18.11; +DPDK_19.08 { + global: + + rte_rand; + rte_srand; + +} DPDK_19.05; + EXPERIMENTAL { global: -- 2.17.1