From nobody Mon Feb 9 20:11:13 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1645454310056485.29120566486677; Mon, 21 Feb 2022 06:38:30 -0800 (PST) Received: from localhost ([::1]:53856 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nM9pd-0004dh-1T for importer@patchew.org; Mon, 21 Feb 2022 09:38:29 -0500 Received: from eggs.gnu.org ([209.51.188.92]:58922) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nM9h7-0004iD-6A for qemu-devel@nongnu.org; Mon, 21 Feb 2022 09:29:42 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:27832) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nM9h3-0003T6-P3 for qemu-devel@nongnu.org; Mon, 21 Feb 2022 09:29:40 -0500 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-447-FtHvdmbZOOemDhabutsk3w-1; Mon, 21 Feb 2022 09:29:33 -0500 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 908751898291; Mon, 21 Feb 2022 14:29:32 +0000 (UTC) Received: from localhost (unknown [10.39.195.91]) by smtp.corp.redhat.com (Postfix) with ESMTP id 154D12B4DE; Mon, 21 Feb 2022 14:29:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1645453776; h=from:from: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=uCWbElNmCbRX2GIEYFaMr3geN+BCQusMA1a7CEL68Ow=; b=ON/ICghP7C23RjGUU+jm28KsxrRESDGMJ+weyhIa0KlO7T68UwQFML8havS6BcOgqwuB+T X9IIoYnb2t6pSrCqEMLHl0UtCe2JNIFjjsNn2CoUKBMySYfQat7T+JfzXuOzK/CnuIOi0w qeLhOLwZ+ZzAthh46t7/DhjlwzcB608= X-MC-Unique: FtHvdmbZOOemDhabutsk3w-1 From: Stefan Hajnoczi To: qemu-devel@nongnu.org Subject: [PATCH v4 3/4] rcu: use coroutine TLS macros Date: Mon, 21 Feb 2022 14:29:06 +0000 Message-Id: <20220221142907.346035-4-stefanha@redhat.com> In-Reply-To: <20220221142907.346035-1-stefanha@redhat.com> References: <20220221142907.346035-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=stefanha@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.129.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Florian Weimer , Kevin Wolf , qemu-block@nongnu.org, Peter Maydell , Richard Henderson , Stefan Hajnoczi , Paolo Bonzini , Fam Zheng , Serge Guelton Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1645454311494100001 Content-Type: text/plain; charset="utf-8" RCU may be used from coroutines. Standard __thread variables cannot be used by coroutines. Use the coroutine TLS macros instead. Signed-off-by: Stefan Hajnoczi --- include/qemu/rcu.h | 7 ++++--- tests/unit/rcutorture.c | 10 +++++----- tests/unit/test-rcu-list.c | 4 ++-- util/rcu.c | 10 +++++----- 4 files changed, 16 insertions(+), 15 deletions(-) diff --git a/include/qemu/rcu.h b/include/qemu/rcu.h index e69efbd47f..b063c6fde8 100644 --- a/include/qemu/rcu.h +++ b/include/qemu/rcu.h @@ -29,6 +29,7 @@ #include "qemu/atomic.h" #include "qemu/notify.h" #include "qemu/sys_membarrier.h" +#include "qemu/coroutine-tls.h" =20 #ifdef __cplusplus extern "C" { @@ -76,11 +77,11 @@ struct rcu_reader_data { NotifierList force_rcu; }; =20 -extern __thread struct rcu_reader_data rcu_reader; +QEMU_DECLARE_CO_TLS(struct rcu_reader_data, rcu_reader) =20 static inline void rcu_read_lock(void) { - struct rcu_reader_data *p_rcu_reader =3D &rcu_reader; + struct rcu_reader_data *p_rcu_reader =3D get_ptr_rcu_reader(); unsigned ctr; =20 if (p_rcu_reader->depth++ > 0) { @@ -96,7 +97,7 @@ static inline void rcu_read_lock(void) =20 static inline void rcu_read_unlock(void) { - struct rcu_reader_data *p_rcu_reader =3D &rcu_reader; + struct rcu_reader_data *p_rcu_reader =3D get_ptr_rcu_reader(); =20 assert(p_rcu_reader->depth !=3D 0); if (--p_rcu_reader->depth > 0) { diff --git a/tests/unit/rcutorture.c b/tests/unit/rcutorture.c index de6f649058..495a4e6f42 100644 --- a/tests/unit/rcutorture.c +++ b/tests/unit/rcutorture.c @@ -122,7 +122,7 @@ static void *rcu_read_perf_test(void *arg) =20 rcu_register_thread(); =20 - *(struct rcu_reader_data **)arg =3D &rcu_reader; + *(struct rcu_reader_data **)arg =3D get_ptr_rcu_reader(); qatomic_inc(&nthreadsrunning); while (goflag =3D=3D GOFLAG_INIT) { g_usleep(1000); @@ -148,7 +148,7 @@ static void *rcu_update_perf_test(void *arg) =20 rcu_register_thread(); =20 - *(struct rcu_reader_data **)arg =3D &rcu_reader; + *(struct rcu_reader_data **)arg =3D get_ptr_rcu_reader(); qatomic_inc(&nthreadsrunning); while (goflag =3D=3D GOFLAG_INIT) { g_usleep(1000); @@ -253,7 +253,7 @@ static void *rcu_read_stress_test(void *arg) =20 rcu_register_thread(); =20 - *(struct rcu_reader_data **)arg =3D &rcu_reader; + *(struct rcu_reader_data **)arg =3D get_ptr_rcu_reader(); while (goflag =3D=3D GOFLAG_INIT) { g_usleep(1000); } @@ -304,7 +304,7 @@ static void *rcu_update_stress_test(void *arg) struct rcu_stress *cp =3D qatomic_read(&rcu_stress_current); =20 rcu_register_thread(); - *(struct rcu_reader_data **)arg =3D &rcu_reader; + *(struct rcu_reader_data **)arg =3D get_ptr_rcu_reader(); =20 while (goflag =3D=3D GOFLAG_INIT) { g_usleep(1000); @@ -347,7 +347,7 @@ static void *rcu_fake_update_stress_test(void *arg) { rcu_register_thread(); =20 - *(struct rcu_reader_data **)arg =3D &rcu_reader; + *(struct rcu_reader_data **)arg =3D get_ptr_rcu_reader(); while (goflag =3D=3D GOFLAG_INIT) { g_usleep(1000); } diff --git a/tests/unit/test-rcu-list.c b/tests/unit/test-rcu-list.c index 49641e1936..64b81ae058 100644 --- a/tests/unit/test-rcu-list.c +++ b/tests/unit/test-rcu-list.c @@ -171,7 +171,7 @@ static void *rcu_q_reader(void *arg) =20 rcu_register_thread(); =20 - *(struct rcu_reader_data **)arg =3D &rcu_reader; + *(struct rcu_reader_data **)arg =3D get_ptr_rcu_reader(); qatomic_inc(&nthreadsrunning); while (qatomic_read(&goflag) =3D=3D GOFLAG_INIT) { g_usleep(1000); @@ -206,7 +206,7 @@ static void *rcu_q_updater(void *arg) long long n_removed_local =3D 0; struct list_element *el, *prev_el; =20 - *(struct rcu_reader_data **)arg =3D &rcu_reader; + *(struct rcu_reader_data **)arg =3D get_ptr_rcu_reader(); qatomic_inc(&nthreadsrunning); while (qatomic_read(&goflag) =3D=3D GOFLAG_INIT) { g_usleep(1000); diff --git a/util/rcu.c b/util/rcu.c index c91da9f137..b6d6c71cff 100644 --- a/util/rcu.c +++ b/util/rcu.c @@ -65,7 +65,7 @@ static inline int rcu_gp_ongoing(unsigned long *ctr) /* Written to only by each individual reader. Read by both the reader and = the * writers. */ -__thread struct rcu_reader_data rcu_reader; +QEMU_DEFINE_CO_TLS(struct rcu_reader_data, rcu_reader) =20 /* Protected by rcu_registry_lock. */ typedef QLIST_HEAD(, rcu_reader_data) ThreadList; @@ -355,23 +355,23 @@ void drain_call_rcu(void) =20 void rcu_register_thread(void) { - assert(rcu_reader.ctr =3D=3D 0); + assert(get_ptr_rcu_reader()->ctr =3D=3D 0); qemu_mutex_lock(&rcu_registry_lock); - QLIST_INSERT_HEAD(®istry, &rcu_reader, node); + QLIST_INSERT_HEAD(®istry, get_ptr_rcu_reader(), node); qemu_mutex_unlock(&rcu_registry_lock); } =20 void rcu_unregister_thread(void) { qemu_mutex_lock(&rcu_registry_lock); - QLIST_REMOVE(&rcu_reader, node); + QLIST_REMOVE(get_ptr_rcu_reader(), node); qemu_mutex_unlock(&rcu_registry_lock); } =20 void rcu_add_force_rcu_notifier(Notifier *n) { qemu_mutex_lock(&rcu_registry_lock); - notifier_list_add(&rcu_reader.force_rcu, n); + notifier_list_add(&get_ptr_rcu_reader()->force_rcu, n); qemu_mutex_unlock(&rcu_registry_lock); } =20 --=20 2.34.1