From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-14.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2A795C433E0 for ; Wed, 29 Jul 2020 14:34:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0A01822CA1 for ; Wed, 29 Jul 2020 14:34:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="f2sW3pfg"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="xb9lt1FS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727797AbgG2Oes (ORCPT ); Wed, 29 Jul 2020 10:34:48 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:42998 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726987AbgG2Odf (ORCPT ); Wed, 29 Jul 2020 10:33:35 -0400 Date: Wed, 29 Jul 2020 14:33:32 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1596033213; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ENaLXBByTTJ5ISrjtB1c6/CxEdRmK1cicpQfyvi2pmc=; b=f2sW3pfg/LMadIRS+c9GeqialkCEVbjLtL2nJLmgoqTeLFV5p9VQObOatEebZGuwmapGf/ f7b9QnENYubxHpNECbJlF9gzl4Vyr1INPVXD59z9fHM0g3862x5fKlIfSqnWmolUQ5seoU VLo5HIi8IrOFZzm+zrTsa2yUdrYgZu+MaXpG0PPYFwor1tWEIuL2Vm1qIAaXc2JDTbzo09 EFnHsdNDReziqkLJQ5nZzVp4ndNVzqLtDzPDCXTEtTKKhTcIImumRc0lw3Y3WjelVSfTaR sDtU2XcSWIkv+FFiEK9d8JPjldMYJmXVHG3dL0PG9cL7sf7CaJ9wctcOHv2clw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1596033213; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ENaLXBByTTJ5ISrjtB1c6/CxEdRmK1cicpQfyvi2pmc=; b=xb9lt1FS+cIHa+dZULXjHnJYFZ4IiuVPW61a0BpxQ1nw+UhofqRS0kWEscpjiGQM1snjIH +VNg96NWdIFE8oCg== From: "tip-bot2 for Ahmed S. Darwish" Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: locking/core] xfrm: policy: Use sequence counters with associated lock Cc: "Ahmed S. Darwish" , "Peter Zijlstra (Intel)" , x86 , LKML In-Reply-To: <20200720155530.1173732-17-a.darwish@linutronix.de> References: <20200720155530.1173732-17-a.darwish@linutronix.de> MIME-Version: 1.0 Message-ID: <159603321244.4006.14222637112308108738.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the locking/core branch of tip: Commit-ID: 77cc278f7b202e4f16f8596837219d02cb090b96 Gitweb: https://git.kernel.org/tip/77cc278f7b202e4f16f8596837219d02cb090b96 Author: Ahmed S. Darwish AuthorDate: Mon, 20 Jul 2020 17:55:22 +02:00 Committer: Peter Zijlstra CommitterDate: Wed, 29 Jul 2020 16:14:27 +02:00 xfrm: policy: Use sequence counters with associated lock A sequence counter write side critical section must be protected by some form of locking to serialize writers. If the serialization primitive is not disabling preemption implicitly, preemption has to be explicitly disabled before entering the sequence counter write side critical section. A plain seqcount_t does not contain the information of which lock must be held when entering a write side critical section. Use the new seqcount_spinlock_t and seqcount_mutex_t data types instead, which allow to associate a lock with the sequence counter. This enables lockdep to verify that the lock used for writer serialization is held when the write side critical section is entered. If lockdep is disabled this lock association is compiled out and has neither storage size nor runtime overhead. Signed-off-by: Ahmed S. Darwish Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20200720155530.1173732-17-a.darwish@linutronix.de --- net/xfrm/xfrm_policy.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index 564aa64..732a940 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -122,7 +122,7 @@ struct xfrm_pol_inexact_bin { /* list containing '*:*' policies */ struct hlist_head hhead; - seqcount_t count; + seqcount_spinlock_t count; /* tree sorted by daddr/prefix */ struct rb_root root_d; @@ -155,7 +155,7 @@ static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1] __read_mostly; static struct kmem_cache *xfrm_dst_cache __ro_after_init; -static __read_mostly seqcount_t xfrm_policy_hash_generation; +static __read_mostly seqcount_mutex_t xfrm_policy_hash_generation; static struct rhashtable xfrm_policy_inexact_table; static const struct rhashtable_params xfrm_pol_inexact_params; @@ -719,7 +719,7 @@ xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir) INIT_HLIST_HEAD(&bin->hhead); bin->root_d = RB_ROOT; bin->root_s = RB_ROOT; - seqcount_init(&bin->count); + seqcount_spinlock_init(&bin->count, &net->xfrm.xfrm_policy_lock); prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table, &bin->k, &bin->head, @@ -1906,7 +1906,7 @@ static int xfrm_policy_match(const struct xfrm_policy *pol, static struct xfrm_pol_inexact_node * xfrm_policy_lookup_inexact_addr(const struct rb_root *r, - seqcount_t *count, + seqcount_spinlock_t *count, const xfrm_address_t *addr, u16 family) { const struct rb_node *parent; @@ -4153,7 +4153,7 @@ void __init xfrm_init(void) { register_pernet_subsys(&xfrm_net_ops); xfrm_dev_init(); - seqcount_init(&xfrm_policy_hash_generation); + seqcount_mutex_init(&xfrm_policy_hash_generation, &hash_resize_mutex); xfrm_input_init(); #ifdef CONFIG_INET_ESPINTCP