From patchwork Mon Oct 16 06:51:46 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Xu X-Patchwork-Id: 826139 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=) 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 3yFptk17QJz9sPk for ; Mon, 16 Oct 2017 17:53:18 +1100 (AEDT) Received: from localhost ([::1]:59602 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e3zH2-0000NP-5l for incoming@patchwork.ozlabs.org; Mon, 16 Oct 2017 02:53:16 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42245) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e3zGM-0000Lt-EH for qemu-devel@nongnu.org; Mon, 16 Oct 2017 02:52:35 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1e3zGL-00016L-Eo for qemu-devel@nongnu.org; Mon, 16 Oct 2017 02:52:34 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59388) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1e3zGL-00015Y-5m for qemu-devel@nongnu.org; Mon, 16 Oct 2017 02:52:33 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 2620680461; Mon, 16 Oct 2017 06:52:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 2620680461 Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=peterx@redhat.com Received: from pxdev.xzpeter.org.com (dhcp-15-225.nay.redhat.com [10.66.15.225]) by smtp.corp.redhat.com (Postfix) with ESMTP id E73985EE07; Mon, 16 Oct 2017 06:52:29 +0000 (UTC) From: Peter Xu To: qemu-devel@nongnu.org Date: Mon, 16 Oct 2017 14:51:46 +0800 Message-Id: <20171016065216.18162-3-peterx@redhat.com> In-Reply-To: <20171016065216.18162-1-peterx@redhat.com> References: <20171016065216.18162-1-peterx@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Mon, 16 Oct 2017 06:52:32 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v3 02/32] migration: reuse mis->userfault_quit_fd 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: Andrea Arcangeli , Juan Quintela , Alexey Perevalov , peterx@redhat.com, "Dr . David Alan Gilbert" Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" It was only used for quitting the page fault thread before. Let it be something more useful - now we can use it to notify a "wake" for the page fault thread (for any reason), and it only means "quit" if the fault_thread_quit is set. Since we changed what it does, renaming it to userfault_event_fd. Reviewed-by: Dr. David Alan Gilbert Signed-off-by: Peter Xu --- migration/migration.h | 6 ++++-- migration/postcopy-ram.c | 26 +++++++++++++++++--------- 2 files changed, 21 insertions(+), 11 deletions(-) diff --git a/migration/migration.h b/migration/migration.h index b83cceadc4..4642469d27 100644 --- a/migration/migration.h +++ b/migration/migration.h @@ -36,6 +36,8 @@ struct MigrationIncomingState { bool have_fault_thread; QemuThread fault_thread; QemuSemaphore fault_thread_sem; + /* Set this when we want the fault thread to quit */ + bool fault_thread_quit; bool have_listen_thread; QemuThread listen_thread; @@ -43,8 +45,8 @@ struct MigrationIncomingState { /* For the kernel to send us notifications */ int userfault_fd; - /* To tell the fault_thread to quit */ - int userfault_quit_fd; + /* To notify the fault_thread to wake, e.g., when need to quit */ + int userfault_event_fd; QEMUFile *to_src_file; QemuMutex rp_mutex; /* We send replies from multiple threads */ void *postcopy_tmp_page; diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c index bec6c2c66b..07dd29c9d7 100644 --- a/migration/postcopy-ram.c +++ b/migration/postcopy-ram.c @@ -387,17 +387,18 @@ int postcopy_ram_incoming_cleanup(MigrationIncomingState *mis) * currently be at 0, we're going to increment it to 1 */ tmp64 = 1; - if (write(mis->userfault_quit_fd, &tmp64, 8) == 8) { + atomic_set(&mis->fault_thread_quit, 1); + if (write(mis->userfault_event_fd, &tmp64, 8) == 8) { trace_postcopy_ram_incoming_cleanup_join(); qemu_thread_join(&mis->fault_thread); } else { /* Not much we can do here, but may as well report it */ - error_report("%s: incrementing userfault_quit_fd: %s", __func__, + error_report("%s: incrementing userfault_event_fd: %s", __func__, strerror(errno)); } trace_postcopy_ram_incoming_cleanup_closeuf(); close(mis->userfault_fd); - close(mis->userfault_quit_fd); + close(mis->userfault_event_fd); mis->have_fault_thread = false; } @@ -520,7 +521,7 @@ static void *postcopy_ram_fault_thread(void *opaque) pfd[0].fd = mis->userfault_fd; pfd[0].events = POLLIN; pfd[0].revents = 0; - pfd[1].fd = mis->userfault_quit_fd; + pfd[1].fd = mis->userfault_event_fd; pfd[1].events = POLLIN; /* Waiting for eventfd to go positive */ pfd[1].revents = 0; @@ -530,8 +531,15 @@ static void *postcopy_ram_fault_thread(void *opaque) } if (pfd[1].revents) { - trace_postcopy_ram_fault_thread_quit(); - break; + uint64_t tmp64 = 0; + + /* Consume the signal */ + read(mis->userfault_event_fd, &tmp64, 8); + + if (atomic_read(&mis->fault_thread_quit)) { + trace_postcopy_ram_fault_thread_quit(); + break; + } } ret = read(mis->userfault_fd, &msg, sizeof(msg)); @@ -610,9 +618,9 @@ int postcopy_ram_enable_notify(MigrationIncomingState *mis) } /* Now an eventfd we use to tell the fault-thread to quit */ - mis->userfault_quit_fd = eventfd(0, EFD_CLOEXEC); - if (mis->userfault_quit_fd == -1) { - error_report("%s: Opening userfault_quit_fd: %s", __func__, + mis->userfault_event_fd = eventfd(0, EFD_CLOEXEC); + if (mis->userfault_event_fd == -1) { + error_report("%s: Opening userfault_event_fd: %s", __func__, strerror(errno)); close(mis->userfault_fd); return -1;