From patchwork Wed Mar 7 11:00:02 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Juan Quintela X-Patchwork-Id: 882536 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3zx9qv1fHgz9sdh for ; Wed, 7 Mar 2018 22:08:43 +1100 (AEDT) Received: from localhost ([::1]:60764 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1etWw5-0002mi-5F for incoming@patchwork.ozlabs.org; Wed, 07 Mar 2018 06:08:41 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59779) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1etWoP-000544-QY for qemu-devel@nongnu.org; Wed, 07 Mar 2018 06:00:50 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1etWoL-0006H2-1V for qemu-devel@nongnu.org; Wed, 07 Mar 2018 06:00:45 -0500 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:44636 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 1etWoK-0006GZ-Sk for qemu-devel@nongnu.org; Wed, 07 Mar 2018 06:00:40 -0500 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 672BC404084A for ; Wed, 7 Mar 2018 11:00:40 +0000 (UTC) Received: from secure.mitica (ovpn-116-34.ams2.redhat.com [10.36.116.34]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4FD08215CDA7; Wed, 7 Mar 2018 11:00:39 +0000 (UTC) From: Juan Quintela To: qemu-devel@nongnu.org Date: Wed, 7 Mar 2018 12:00:02 +0100 Message-Id: <20180307110010.2205-17-quintela@redhat.com> In-Reply-To: <20180307110010.2205-1-quintela@redhat.com> References: <20180307110010.2205-1-quintela@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Wed, 07 Mar 2018 11:00:40 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Wed, 07 Mar 2018 11:00:40 +0000 (UTC) for IP:'10.11.54.6' DOMAIN:'int-mx06.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 v10 16/24] 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" 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 | 37 ++++++++++++++++++++++++++++++++++++- migration/trace-events | 1 + 2 files changed, 37 insertions(+), 1 deletion(-) diff --git a/migration/ram.c b/migration/ram.c index 153c7560cb..0266bd200c 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -551,6 +551,7 @@ struct MultiFDRecvParams { QemuMutex mutex; bool running; bool quit; + bool sync; }; typedef struct MultiFDRecvParams MultiFDRecvParams; @@ -558,6 +559,8 @@ struct { MultiFDRecvParams *params; /* number of created threads */ int count; + /* syncs main thread and channels */ + QemuSemaphore sem_main; } *multifd_recv_state; static void terminate_multifd_recv_threads(Error *errp) @@ -605,6 +608,7 @@ int multifd_load_cleanup(Error **errp) g_free(p->name); p->name = NULL; } + qemu_sem_destroy(&multifd_recv_state->sem_main); g_free(multifd_recv_state->params); multifd_recv_state->params = NULL; g_free(multifd_recv_state); @@ -613,18 +617,45 @@ int multifd_load_cleanup(Error **errp) return ret; } +static void multifd_recv_sync_main(void) +{ + int i; + + if (!migrate_use_multifd()) { + return; + } + for (i = 0; i < migrate_multifd_channels(); i++) { + MultiFDRecvParams *p = &multifd_recv_state->params[i]; + + qemu_mutex_lock(&p->mutex); + p->sync = true; + qemu_mutex_unlock(&p->mutex); + qemu_sem_post(&p->sem); + } + for (i = 0; i < migrate_multifd_channels(); i++) { + qemu_sem_wait(&multifd_recv_state->sem_main); + } + trace_multifd_recv_sync_main(); +} + static void *multifd_recv_thread(void *opaque) { MultiFDRecvParams *p = opaque; while (true) { + qemu_sem_wait(&p->sem); qemu_mutex_lock(&p->mutex); + if (p->sync) { + p->sync = false; + qemu_mutex_unlock(&p->mutex); + qemu_sem_post(&multifd_recv_state->sem_main); + continue; + } if (p->quit) { qemu_mutex_unlock(&p->mutex); break; } qemu_mutex_unlock(&p->mutex); - qemu_sem_wait(&p->sem); } return NULL; @@ -642,6 +673,7 @@ int multifd_load_setup(void) multifd_recv_state = g_malloc0(sizeof(*multifd_recv_state)); multifd_recv_state->params = g_new0(MultiFDRecvParams, thread_count); atomic_set(&multifd_recv_state->count, 0); + qemu_sem_init(&multifd_recv_state->sem_main, 0); for (i = 0; i < thread_count; i++) { MultiFDRecvParams *p = &multifd_recv_state->params[i]; @@ -655,6 +687,7 @@ int multifd_load_setup(void) QEMU_THREAD_JOINABLE); atomic_inc(&multifd_recv_state->count); } + return 0; } @@ -2868,6 +2901,7 @@ 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" @@ -3053,6 +3087,7 @@ static int ram_load(QEMUFile *f, void *opaque, int version_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 97b5ac564f..76075c26bc 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -78,6 +78,7 @@ ram_postcopy_send_discard_bitmap(void) "" ram_save_page(const char *rbname, uint64_t offset, void *host) "%s: offset: 0x%" PRIx64 " host: %p" ram_save_queue_pages(const char *rbname, size_t start, size_t len) "%s: start: 0x%zx len: 0x%zx" multifd_send_sync_main(void) "" +multifd_recv_sync_main(void) "" # migration/migration.c await_return_path_close_on_source_close(void) ""