Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E194DC433F5 for ; Sun, 21 Nov 2021 16:50:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238502AbhKUQxi (ORCPT ); Sun, 21 Nov 2021 11:53:38 -0500 Received: from mo4-p04-ob.smtp.rzone.de ([85.215.255.121]:9000 "EHLO mo4-p04-ob.smtp.rzone.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238387AbhKUQxC (ORCPT ); Sun, 21 Nov 2021 11:53:02 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1637513320; s=strato-dkim-0002; d=chronox.de; h=References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Cc:Date: From:Subject:Sender; bh=cmDmxmsj+vi3iFFx9IyinCwhf8EiGpD4ffVQNQAHtI4=; b=CkFfriCL+SWOC/ODilx5k47FXINAVXcyrboj2HNRLKPy0elfToJE1WOBOrDtgEJzxZ OHW767gHlGO9bwE79uh4LGUyr4QOiy5/PdgU2XzO/6s3dYlYw9JOoKaepMxW760eIiLa AfJESxbx7OtVXhN7vEDZAhxnEyF7zhbNIbt0gXTxiBWOe2G8O/iJ7PpJJq5dRD33+ePs jGYTa/7+M1j0gvxu5rScyOzNkao1TrQ/3VS63Wj0hrDP0r08LDQ53u4jbYWZSJIzC/yv HrH/afETw3aNTzKgg6KitmS+FxaU3budGdjURKBea3+susz2L0VqTaOb0CqUYsMcMdYh GELQ== Authentication-Results: strato.com; dkim=none X-RZG-AUTH: ":P2ERcEykfu11Y98lp/T7+hdri+uKZK8TKWEqNyiHySGSa9k9xmwdNnzGHXPbJvSfE+K2" X-RZG-CLASS-ID: mo00 Received: from positron.chronox.de by smtp.strato.de (RZmta 47.34.5 DYNA|AUTH) with ESMTPSA id U02dfbxALGmc3Wl (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256 bits)) (Client did not present a certificate); Sun, 21 Nov 2021 17:48:38 +0100 (CET) From: Stephan =?ISO-8859-1?Q?M=FCller?= To: Tso Ted , linux-crypto@vger.kernel.org Cc: Willy Tarreau , Nicolai Stange , LKML , Arnd Bergmann , Greg Kroah-Hartman , "Eric W. Biederman" , "Alexander E. Patrakov" , "Ahmed S. Darwish" , Matthew Garrett , Vito Caputo , Andreas Dilger , Jan Kara , Ray Strode , William Jon McCann , zhangjs , Andy Lutomirski , Florian Weimer , Lennart Poettering , Peter Matthias , Marcelo Henrique Cerri , Neil Horman , Randy Dunlap , Julia Lawall , Dan Carpenter , Andy Lavr , Eric Biggers , "Jason A. Donenfeld" , Petr Tesarik , John Haxby , Alexander Lobakin , Jirka Hladky Subject: [PATCH v43 04/15] LRNG - allocate one DRNG instance per NUMA node Date: Sun, 21 Nov 2021 17:41:37 +0100 Message-ID: <5319346.rdbgypaU67@positron.chronox.de> In-Reply-To: <2036923.9o76ZdvQCi@positron.chronox.de> References: <2036923.9o76ZdvQCi@positron.chronox.de> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In order to improve NUMA-locality when serving getrandom(2) requests, allocate one DRNG instance per node. The DRNG instance that is present right from the start of the kernel is reused as the first per-NUMA-node DRNG. For all remaining online NUMA nodes a new DRNG instance is allocated. During boot time, the multiple DRNG instances are seeded sequentially. With this, the first DRNG instance (referenced as the initial DRNG in the code) is completely seeded with 256 bits of entropy before the next DRNG instance is completely seeded. When random numbers are requested, the NUMA-node-local DRNG is checked whether it has been already fully seeded. If this is not the case, the initial DRNG is used to serve the request. CC: Torsten Duwe CC: "Eric W. Biederman" CC: "Alexander E. Patrakov" CC: "Ahmed S. Darwish" CC: "Theodore Y. Ts'o" CC: Willy Tarreau CC: Matthew Garrett CC: Vito Caputo CC: Andreas Dilger CC: Jan Kara CC: Ray Strode CC: William Jon McCann CC: zhangjs CC: Andy Lutomirski CC: Florian Weimer CC: Lennart Poettering CC: Nicolai Stange CC: Eric Biggers Reviewed-by: Alexander Lobakin Tested-by: Alexander Lobakin Reviewed-by: Marcelo Henrique Cerri Reviewed-by: Roman Drahtmueller Tested-by: Marcelo Henrique Cerri Tested-by: Neil Horman Tested-by: Jirka Hladky Reviewed-by: Jirka Hladky Signed-off-by: Stephan Mueller --- drivers/char/lrng/Makefile | 1 + drivers/char/lrng/lrng_numa.c | 122 ++++++++++++++++++++++++++++++++++ 2 files changed, 123 insertions(+) create mode 100644 drivers/char/lrng/lrng_numa.c diff --git a/drivers/char/lrng/Makefile b/drivers/char/lrng/Makefile index d7df72a702e4..1e722e0967e0 100644 --- a/drivers/char/lrng/Makefile +++ b/drivers/char/lrng/Makefile @@ -9,3 +9,4 @@ obj-y += lrng_es_mgr.o lrng_aux.o \ obj-$(CONFIG_LRNG_IRQ) += lrng_es_irq.o obj-$(CONFIG_SYSCTL) += lrng_proc.o +obj-$(CONFIG_NUMA) += lrng_numa.o diff --git a/drivers/char/lrng/lrng_numa.c b/drivers/char/lrng/lrng_numa.c new file mode 100644 index 000000000000..fbfb40a5fb8d --- /dev/null +++ b/drivers/char/lrng/lrng_numa.c @@ -0,0 +1,122 @@ +// SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause +/* + * LRNG NUMA support + * + * Copyright (C) 2016 - 2021, Stephan Mueller + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include + +#include "lrng_internal.h" + +static struct lrng_drng **lrng_drng __read_mostly = NULL; + +struct lrng_drng **lrng_drng_instances(void) +{ + return smp_load_acquire(&lrng_drng); +} + +/* Allocate the data structures for the per-NUMA node DRNGs */ +static void _lrng_drngs_numa_alloc(struct work_struct *work) +{ + struct lrng_drng **drngs; + struct lrng_drng *lrng_drng_init = lrng_drng_init_instance(); + u32 node; + bool init_drng_used = false; + + mutex_lock(&lrng_crypto_cb_update); + + /* per-NUMA-node DRNGs are already present */ + if (lrng_drng) + goto unlock; + + drngs = kcalloc(nr_node_ids, sizeof(void *), GFP_KERNEL|__GFP_NOFAIL); + for_each_online_node(node) { + struct lrng_drng *drng; + + if (!init_drng_used) { + drngs[node] = lrng_drng_init; + init_drng_used = true; + continue; + } + + drng = kmalloc_node(sizeof(struct lrng_drng), + GFP_KERNEL|__GFP_NOFAIL, node); + memset(drng, 0, sizeof(lrng_drng)); + + drng->crypto_cb = lrng_drng_init->crypto_cb; + drng->drng = drng->crypto_cb->lrng_drng_alloc( + LRNG_DRNG_SECURITY_STRENGTH_BYTES); + if (IS_ERR(drng->drng)) { + kfree(drng); + goto err; + } + + drng->hash = drng->crypto_cb->lrng_hash_alloc(); + if (IS_ERR(drng->hash)) { + drng->crypto_cb->lrng_drng_dealloc(drng->drng); + kfree(drng); + goto err; + } + + mutex_init(&drng->lock); + spin_lock_init(&drng->spin_lock); + rwlock_init(&drng->hash_lock); + + /* + * Switch the hash used by the per-CPU pool. + * We do not need to lock the new hash as it is not usable yet + * due to **drngs not yet being initialized. + */ + if (lrng_pcpu_switch_hash(node, drng->crypto_cb, drng->hash, + &lrng_cc20_crypto_cb)) + goto err; + + /* + * No reseeding of NUMA DRNGs from previous DRNGs as this + * would complicate the code. Let it simply reseed. + */ + lrng_drng_reset(drng); + drngs[node] = drng; + + lrng_pool_inc_numa_node(); + pr_info("DRNG and entropy pool read hash for NUMA node %d allocated\n", + node); + } + + /* counterpart to smp_load_acquire in lrng_drng_instances */ + if (!cmpxchg_release(&lrng_drng, NULL, drngs)) { + lrng_pool_all_numa_nodes_seeded(false); + goto unlock; + } + +err: + for_each_online_node(node) { + struct lrng_drng *drng = drngs[node]; + + if (drng == lrng_drng_init) + continue; + + if (drng) { + lrng_pcpu_switch_hash(node, &lrng_cc20_crypto_cb, NULL, + drng->crypto_cb); + drng->crypto_cb->lrng_hash_dealloc(drng->hash); + drng->crypto_cb->lrng_drng_dealloc(drng->drng); + kfree(drng); + } + } + kfree(drngs); + +unlock: + mutex_unlock(&lrng_crypto_cb_update); +} + +static DECLARE_WORK(lrng_drngs_numa_alloc_work, _lrng_drngs_numa_alloc); + +void lrng_drngs_numa_alloc(void) +{ + schedule_work(&lrng_drngs_numa_alloc_work); +} -- 2.31.1