From nobody Sat Oct 25 13:17:43 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 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 [208.118.235.17]) by mx.zohomail.com with SMTPS id 152120157262460.31681162370319; Fri, 16 Mar 2018 04:59:32 -0700 (PDT) Received: from localhost ([::1]:56259 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ewo1D-00022W-Mp for importer@patchew.org; Fri, 16 Mar 2018 07:59:31 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59110) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ewnwG-0006ed-A0 for qemu-devel@nongnu.org; Fri, 16 Mar 2018 07:54:27 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ewnwF-0002b2-56 for qemu-devel@nongnu.org; Fri, 16 Mar 2018 07:54:24 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:34970 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ewnwF-0002a2-0o for qemu-devel@nongnu.org; Fri, 16 Mar 2018 07:54:23 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8C7664023156 for ; Fri, 16 Mar 2018 11:54:22 +0000 (UTC) Received: from secure.mitica (ovpn-116-95.ams2.redhat.com [10.36.116.95]) by smtp.corp.redhat.com (Postfix) with ESMTP id 82F4EC1FE0; Fri, 16 Mar 2018 11:54:21 +0000 (UTC) From: Juan Quintela To: qemu-devel@nongnu.org Date: Fri, 16 Mar 2018 12:53:56 +0100 Message-Id: <20180316115403.4148-9-quintela@redhat.com> In-Reply-To: <20180316115403.4148-1-quintela@redhat.com> References: <20180316115403.4148-1-quintela@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Fri, 16 Mar 2018 11:54:22 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Fri, 16 Mar 2018 11:54:22 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'quintela@redhat.com' RCPT:'' X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 66.187.233.73 Subject: [Qemu-devel] [PATCH v11 08/15] migration: Synchronize recv threads X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: lvivier@redhat.com, dgilbert@redhat.com, peterx@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" We synchronize all threads each RAM_SAVE_FLAG_EOS. Bitmap synchronizations don't happen inside a ram section, so we are safe about two channels trying to overwrite the same memory. Signed-off-by: Juan Quintela --- migration/ram.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++= ++- migration/trace-events | 3 +++ 2 files changed, 51 insertions(+), 1 deletion(-) diff --git a/migration/ram.c b/migration/ram.c index 6aeb63f6ef..4ba03cf9c9 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -565,6 +565,7 @@ struct MultiFDRecvParams { QemuMutex mutex; bool running; bool quit; + bool sync; }; typedef struct MultiFDRecvParams MultiFDRecvParams; =20 @@ -572,6 +573,8 @@ struct { MultiFDRecvParams *params; /* number of created threads */ int count; + /* syncs main thread and channels */ + QemuSemaphore sem_main; } *multifd_recv_state; =20 static void multifd_recv_terminate_threads(Error *errp) @@ -618,6 +621,7 @@ int multifd_load_cleanup(Error **errp) g_free(p->name); p->name =3D NULL; } + qemu_sem_destroy(&multifd_recv_state->sem_main); g_free(multifd_recv_state->params); multifd_recv_state->params =3D NULL; g_free(multifd_recv_state); @@ -626,19 +630,59 @@ int multifd_load_cleanup(Error **errp) return ret; } =20 +static void multifd_recv_sync_main(void) +{ + int i; + + if (!migrate_use_multifd()) { + return; + } + for (i =3D 0; i < migrate_multifd_channels(); i++) { + MultiFDRecvParams *p =3D &multifd_recv_state->params[i]; + + trace_multifd_recv_sync_signal(p->id, p->quit, p->running); + + qemu_mutex_lock(&p->mutex); + p->sync =3D true; + qemu_mutex_unlock(&p->mutex); + qemu_sem_post(&p->sem); + } + for (i =3D 0; i < migrate_multifd_channels(); i++) { + MultiFDRecvParams *p =3D &multifd_recv_state->params[i]; + bool wait; + + trace_multifd_recv_sync_wait(p->id, p->quit, p->running); + + qemu_mutex_lock(&p->mutex); + wait =3D p->running; + qemu_mutex_unlock(&p->mutex); + + if (wait) { + qemu_sem_wait(&multifd_recv_state->sem_main); + } + } + trace_multifd_recv_sync_main(); +} + static void *multifd_recv_thread(void *opaque) { MultiFDRecvParams *p =3D opaque; =20 while (true) { + qemu_sem_wait(&p->sem); qemu_mutex_lock(&p->mutex); + if (p->sync) { + p->sync =3D false; + qemu_mutex_unlock(&p->mutex); + qemu_sem_post(&multifd_recv_state->sem_main); + continue; + } if (p->quit) { p->running =3D false; qemu_mutex_unlock(&p->mutex); break; } qemu_mutex_unlock(&p->mutex); - qemu_sem_wait(&p->sem); } =20 return NULL; @@ -656,6 +700,7 @@ int multifd_load_setup(void) multifd_recv_state =3D g_malloc0(sizeof(*multifd_recv_state)); multifd_recv_state->params =3D g_new0(MultiFDRecvParams, thread_count); atomic_set(&multifd_recv_state->count, 0); + qemu_sem_init(&multifd_recv_state->sem_main, 0); for (i =3D 0; i < thread_count; i++) { MultiFDRecvParams *p =3D &multifd_recv_state->params[i]; =20 @@ -2890,6 +2935,7 @@ static int ram_load_postcopy(QEMUFile *f) break; case RAM_SAVE_FLAG_EOS: /* normal exit */ + multifd_recv_sync_main(); break; default: error_report("Unknown combination of migration flags: %#x" @@ -3075,6 +3121,7 @@ static int ram_load(QEMUFile *f, void *opaque, int ve= rsion_id) break; case RAM_SAVE_FLAG_EOS: /* normal exit */ + multifd_recv_sync_main(); break; default: if (flags & RAM_SAVE_FLAG_HOOK) { diff --git a/migration/trace-events b/migration/trace-events index 845612c177..551d325daf 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -80,6 +80,9 @@ ram_save_queue_pages(const char *rbname, size_t start, si= ze_t len) "%s: start: 0 multifd_send_sync_main(void) "" multifd_send_sync_signal(uint8_t id, bool quit, bool running) "channel %d = quit %d running %d" multifd_send_sync_wait(uint8_t id, bool quit, bool running) "channel %d qu= it %d running %d" +multifd_recv_sync_main(void) "" +multifd_recv_sync_signal(uint8_t id, bool quit, bool running) "channel %d = quit %d running %d" +multifd_recv_sync_wait(uint8_t id, bool quit, bool running) "channel %d qu= it %d running %d" =20 # migration/migration.c await_return_path_close_on_source_close(void) "" --=20 2.14.3