From patchwork Wed May 18 19:14:17 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adhemerval Zanella X-Patchwork-Id: 54178 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id F2B3B384406B for ; Wed, 18 May 2022 19:15:51 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org F2B3B384406B DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1652901352; bh=3zIjisXoOixJw13DfrGhG5y/xlWl++xtScqyCw8Qg8A=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To: From; b=phY+XPQDcOwoCvekwwY/6j2+kz4Y963poC2KdhlhcuDet4PB7RPI5yIzJep4WMGOd 7z/zYqy5cGArfkFatJowhfCAhAIDkUr+LTFniTAquYPTdQlTGLWZlz0crGnH7dgftf ek/Riqbj0bA/KitncTS5Z6vxs5aH1/VtnGBsiTAM= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from mail-oa1-x32.google.com (mail-oa1-x32.google.com [IPv6:2001:4860:4864:20::32]) by sourceware.org (Postfix) with ESMTPS id 8F68E3848580 for ; Wed, 18 May 2022 19:14:38 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 8F68E3848580 Received: by mail-oa1-x32.google.com with SMTP id 586e51a60fabf-edf3b6b0f2so3966747fac.9 for ; Wed, 18 May 2022 12:14:38 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=3zIjisXoOixJw13DfrGhG5y/xlWl++xtScqyCw8Qg8A=; b=1dBSKRCAo+C3BflqCmAYY/QijAfP48YwOnksHtR0CUL5G9Fn8q+z+bm6LQYFsh5GUN +MdyocR3MgYwJnc+JE+CtUS4myFJRJy0kxot0xO8FCTHFESnBtjUfNx4eb3JUX9XUNY5 fAHyZnqU/GKWXLXsF2fS3U/G6wE9I2Z1oZEIWLikxjPFl2BnlZ0WJI9/wtejfwEylHVL fzUVC4hvHNWa6Xvg8GpMpOafiDGPoSpk65tZw/XTJXXggT7AOFiCPSKuD6MJnldZ4T/F /2coepO82xAqaH+qLxtjMqZIu58npl0aNpHC9KGBeCfN2bOeG5twDg2w9L9pplf3770K 3XRA== X-Gm-Message-State: AOAM5308wR1kKimK7hCUd0IgOOiiYjNHskGou03U0Y2CbfsQIEKCoE+M ykd8Zc4sW4iPOvc+7v3pBaFWaa58RRl/9Q== X-Google-Smtp-Source: ABdhPJzE5WbGbkCfMP6PF4/toIWkG21CWDGcb10e92eH1x0yEaTvgUpm+2N3svKT3aAKpSyYPNZfvg== X-Received: by 2002:a05:6870:a707:b0:e2:cc85:d98 with SMTP id g7-20020a056870a70700b000e2cc850d98mr986590oam.131.1652901277499; Wed, 18 May 2022 12:14:37 -0700 (PDT) Received: from birita.. ([2804:431:c7cb:cdd6:1a62:669c:7cd2:ac43]) by smtp.gmail.com with ESMTPSA id i131-20020acaea89000000b00325cda1ffbasm1033011oih.57.2022.05.18.12.14.36 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 18 May 2022 12:14:36 -0700 (PDT) To: libc-alpha@sourceware.org Subject: [PATCH v6 03/10] benchtests: Add arc4random benchtest Date: Wed, 18 May 2022 16:14:17 -0300 Message-Id: <20220518191424.3630729-4-adhemerval.zanella@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220518191424.3630729-1-adhemerval.zanella@linaro.org> References: <20220518191424.3630729-1-adhemerval.zanella@linaro.org> MIME-Version: 1.0 X-Spam-Status: No, score=-11.9 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, KAM_SHORT, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Adhemerval Zanella via Libc-alpha From: Adhemerval Zanella Reply-To: Adhemerval Zanella Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Sender: "Libc-alpha" It shows both throughput (total bytes obtained in the test duration) and latecy for both arc4random and arc4random_buf with different sizes. Checked on x86_64-linux-gnu, aarch64-linux, and powerpc64le-linux-gnu. --- benchtests/Makefile | 5 +- benchtests/bench-arc4random.c | 224 ++++++++++++++++++++++++++++++++++ stdlib/arc4random.c | 14 +-- 3 files changed, 235 insertions(+), 8 deletions(-) create mode 100644 benchtests/bench-arc4random.c diff --git a/benchtests/Makefile b/benchtests/Makefile index de9de5cf58..76583d45a3 100644 --- a/benchtests/Makefile +++ b/benchtests/Makefile @@ -227,7 +227,10 @@ LOCALES := \ include ../gen-locales.mk endif -stdlib-benchset := strtod +stdlib-benchset := \ + arc4random \ + strtod \ + # stdlib-benchset stdio-common-benchset := sprintf diff --git a/benchtests/bench-arc4random.c b/benchtests/bench-arc4random.c new file mode 100644 index 0000000000..626f2ba48c --- /dev/null +++ b/benchtests/bench-arc4random.c @@ -0,0 +1,224 @@ +/* arc4random benchmarks. + Copyright (C) 2022 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include "bench-timing.h" +#include "json-lib.h" +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* Prevent compiler to optimize away call. */ +#define DO_NOT_OPTIMIZE(__value) \ + ({ \ + __typeof (__value) __v = (__value); \ + asm volatile("" : : "r,m" (__v) : "memory");\ + }) + +static volatile sig_atomic_t timer_finished; + +static void timer_callback (int unused) +{ + timer_finished = 1; +} + +static timer_t timer; + +/* Run for approximately DURATION seconds, and it does not matter who + receive the signal (so not need to mask it on main thread). */ +static void +timer_start (void) +{ + timer_finished = 0; + timer = support_create_timer (DURATION, 0, false, timer_callback); +} +static void +timer_stop (void) +{ + support_delete_timer (timer); +} + +static const uint32_t sizes[] = { 0, 16, 32, 48, 64, 80, 96, 112, 128 }; + +static double +bench_throughput (void) +{ + uint64_t n = 0; + + struct timespec start, end; + clock_gettime (CLOCK_MONOTONIC, &start); + while (1) + { + DO_NOT_OPTIMIZE (arc4random ()); + n++; + + if (timer_finished == 1) + break; + } + clock_gettime (CLOCK_MONOTONIC, &end); + struct timespec diff = timespec_sub (end, start); + + double total = (double) n * sizeof (uint32_t); + double duration = (double) diff.tv_sec + + (double) diff.tv_nsec / TIMESPEC_HZ; + + return total / duration; +} + +static double +bench_latency (void) +{ + timing_t start, stop, cur; + const size_t iters = 1024; + + TIMING_NOW (start); + for (size_t i = 0; i < iters; i++) + DO_NOT_OPTIMIZE (arc4random ()); + TIMING_NOW (stop); + + TIMING_DIFF (cur, start, stop); + + return (double) (cur) / (double) iters; +} + +static double +bench_buf_throughput (size_t len) +{ + uint8_t buf[len]; + uint64_t n = 0; + + struct timespec start, end; + clock_gettime (CLOCK_MONOTONIC, &start); + while (1) + { + arc4random_buf (buf, len); + n++; + + if (timer_finished == 1) + break; + } + clock_gettime (CLOCK_MONOTONIC, &end); + struct timespec diff = timespec_sub (end, start); + + double total = (double) n * len; + double duration = (double) diff.tv_sec + + (double) diff.tv_nsec / TIMESPEC_HZ; + + return total / duration; +} + +static double +bench_buf_latency (size_t len) +{ + timing_t start, stop, cur; + const size_t iters = 1024; + + uint8_t buf[len]; + + TIMING_NOW (start); + for (size_t i = 0; i < iters; i++) + arc4random_buf (buf, len); + TIMING_NOW (stop); + + TIMING_DIFF (cur, start, stop); + + return (double) (cur) / (double) iters; +} + +static void +bench_singlethread (json_ctx_t *json_ctx) +{ + json_element_object_begin (json_ctx); + + json_array_begin (json_ctx, "throughput"); + for (int i = 0; i < array_length (sizes); i++) + { + timer_start (); + double r = sizes[i] == 0 + ? bench_throughput () : bench_buf_throughput (sizes[i]); + timer_stop (); + + json_element_double (json_ctx, r); + } + json_array_end (json_ctx); + + json_array_begin (json_ctx, "latency"); + for (int i = 0; i < array_length (sizes); i++) + { + timer_start (); + double r = sizes[i] == 0 + ? bench_latency () : bench_buf_latency (sizes[i]); + timer_stop (); + + json_element_double (json_ctx, r); + } + json_array_end (json_ctx); + + json_element_object_end (json_ctx); +} + +static void +run_bench (json_ctx_t *json_ctx, const char *name, + char *const*fnames, size_t fnameslen, + void (*bench)(json_ctx_t *ctx)) +{ + json_attr_object_begin (json_ctx, name); + json_array_begin (json_ctx, "functions"); + for (int i = 0; i < fnameslen; i++) + json_element_string (json_ctx, fnames[i]); + json_array_end (json_ctx); + + json_array_begin (json_ctx, "results"); + bench (json_ctx); + json_array_end (json_ctx); + json_attr_object_end (json_ctx); +} + +static int +do_test (void) +{ + char *fnames[array_length (sizes)]; + for (int i = 0; i < array_length (sizes); i++) + if (sizes[i] == 0) + fnames[i] = xasprintf ("arc4random"); + else + fnames[i] = xasprintf ("arc4random_buf(%u)", sizes[i]); + + json_ctx_t json_ctx; + json_init (&json_ctx, 0, stdout); + + json_document_begin (&json_ctx); + json_attr_string (&json_ctx, "timing_type", TIMING_TYPE); + + run_bench (&json_ctx, "single-thread", fnames, array_length (fnames), + bench_singlethread); + + json_document_end (&json_ctx); + + for (int i = 0; i < array_length (sizes); i++) + free (fnames[i]); + + return 0; +} + +#include diff --git a/stdlib/arc4random.c b/stdlib/arc4random.c index f6553dfd7d..74c917b9b9 100644 --- a/stdlib/arc4random.c +++ b/stdlib/arc4random.c @@ -25,9 +25,9 @@ #include #include -/* Besides the cipher state 'ctx', it keeps two counters: 'have' is the - current valid bytes not yet consumed in 'buf', while 'count' is the maximum - number of bytes until a reseed. +/* arc4random keeps two counters: 'have' is the current valid bytes not yet + consumed in 'buf' while 'count' is the maximum number of bytes until a + reseed. Both the initial seed and reseed try to obtain entropy from the kernel and abort the process if none could be obtained. @@ -81,10 +81,10 @@ arc4random_getrandom_failure (void) __libc_fatal ("Fatal glibc error: Cannot get entropy for arc4random\n"); } -/* Fork detection is done by checking if MADV_WIPEONFORK supported. If not - the fork callback will reset the state on the fork call. It does not - handle direct clone calls, nor vfork or _Fork (arc4random is not - async-signal-safe due the internal lock usage). */ +/* If the kernel supports MADV_WIPEONFORK it is used to provide fork + detection. Otherwise, the state is resetied with an atfork handler. The + latter does not handle direct clone calls, nor vfork or _Fork (arc4random + is not async-signal-safe due to the internal lock usage). */ static void arc4random_init (uint8_t *buf) {