From patchwork Tue Dec 11 08:24:49 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Wang, Wei W" X-Patchwork-Id: 10723213 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9D7D391E for ; Tue, 11 Dec 2018 08:59:29 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8E50A29B3B for ; Tue, 11 Dec 2018 08:59:29 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 82C6529DA3; Tue, 11 Dec 2018 08:59:29 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id D17AB29BF1 for ; Tue, 11 Dec 2018 08:59:27 +0000 (UTC) Received: from localhost ([::1]:36615 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gWdt0-0002TN-Pz for patchwork-qemu-devel@patchwork.kernel.org; Tue, 11 Dec 2018 03:59:26 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51597) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gWdrc-0002ST-Ep for qemu-devel@nongnu.org; Tue, 11 Dec 2018 03:58:01 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gWdrb-0006Fh-EM for qemu-devel@nongnu.org; Tue, 11 Dec 2018 03:58:00 -0500 Received: from mga07.intel.com ([134.134.136.100]:27021) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gWdrb-0006FH-4o for qemu-devel@nongnu.org; Tue, 11 Dec 2018 03:57:59 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 11 Dec 2018 00:57:58 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,341,1539673200"; d="scan'208";a="117803119" Received: from devel-ww.sh.intel.com ([10.239.48.119]) by orsmga001.jf.intel.com with ESMTP; 11 Dec 2018 00:57:56 -0800 From: Wei Wang To: qemu-devel@nongnu.org, virtio-dev@lists.oasis-open.org, mst@redhat.com, quintela@redhat.com, dgilbert@redhat.com, peterx@redhat.com Date: Tue, 11 Dec 2018 16:24:49 +0800 Message-Id: <1544516693-5395-4-git-send-email-wei.w.wang@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1544516693-5395-1-git-send-email-wei.w.wang@intel.com> References: <1544516693-5395-1-git-send-email-wei.w.wang@intel.com> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 134.134.136.100 Subject: [Qemu-devel] [PATCH v11 3/7] migration: use bitmap_mutex in migration_bitmap_clear_dirty 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: pbonzini@redhat.com, liliang.opensource@gmail.com, nilal@redhat.com, wei.w.wang@intel.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP The bitmap mutex is used to synchronize threads to update the dirty bitmap and the migration_dirty_pages counter. For example, the free page optimization clears bits of free pages from the bitmap in an iothread context. This patch makes migration_bitmap_clear_dirty update the bitmap and counter under the mutex. Signed-off-by: Wei Wang CC: Dr. David Alan Gilbert CC: Juan Quintela CC: Michael S. Tsirkin CC: Peter Xu Reviewed-by: Peter Xu --- migration/ram.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/migration/ram.c b/migration/ram.c index 7e7deec..01d267f 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -316,7 +316,7 @@ struct RAMState { uint64_t target_page_count; /* number of dirty bits in the bitmap */ uint64_t migration_dirty_pages; - /* protects modification of the bitmap */ + /* Protects modification of the bitmap and migration dirty pages */ QemuMutex bitmap_mutex; /* The RAMBlock used in the last src_page_requests */ RAMBlock *last_req_rb; @@ -1556,11 +1556,14 @@ static inline bool migration_bitmap_clear_dirty(RAMState *rs, { bool ret; + qemu_mutex_lock(&rs->bitmap_mutex); ret = test_and_clear_bit(page, rb->bmap); if (ret) { rs->migration_dirty_pages--; } + qemu_mutex_unlock(&rs->bitmap_mutex); + return ret; }