From patchwork Fri Jun 26 10:09:39 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Li Zhijian X-Patchwork-Id: 488686 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org 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 4C59414028F for ; Fri, 26 Jun 2015 20:10:39 +1000 (AEST) Received: from localhost ([::1]:59166 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z8Qaj-00077S-0e for incoming@patchwork.ozlabs.org; Fri, 26 Jun 2015 06:10:37 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48555) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z8QaL-0006dO-Dt for qemu-devel@nongnu.org; Fri, 26 Jun 2015 06:10:14 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z8QaI-0003I3-2y for qemu-devel@nongnu.org; Fri, 26 Jun 2015 06:10:13 -0400 Received: from [59.151.112.132] (port=12874 helo=heian.cn.fujitsu.com) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z8QaG-0002x3-E9 for qemu-devel@nongnu.org; Fri, 26 Jun 2015 06:10:10 -0400 X-IronPort-AV: E=Sophos;i="5.13,665,1427731200"; d="scan'208";a="97788550" Received: from unknown (HELO edo.cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 26 Jun 2015 18:13:48 +0800 Received: from G08CNEXCHPEKD02.g08.fujitsu.local (localhost.localdomain [127.0.0.1]) by edo.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id t5QA872w018832; Fri, 26 Jun 2015 18:08:07 +0800 Received: from G08FNSTD140138.g08.fujitsu.local (10.167.226.45) by G08CNEXCHPEKD02.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server (TLS) id 14.3.181.6; Fri, 26 Jun 2015 18:09:45 +0800 From: Li Zhijian To: , , , Date: Fri, 26 Jun 2015 18:09:39 +0800 Message-ID: <1435313380-12857-2-git-send-email-lizhijian@cn.fujitsu.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1435313380-12857-1-git-send-email-lizhijian@cn.fujitsu.com> References: <1435313380-12857-1-git-send-email-lizhijian@cn.fujitsu.com> MIME-Version: 1.0 X-Originating-IP: [10.167.226.45] X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 59.151.112.132 Cc: Li Zhijian Subject: [Qemu-devel] [PATCH v2 1/2] migration: protect migration_bitmap X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Signed-off-by: Li Zhijian Signed-off-by: Wen Congyang --- migration/ram.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 57368e1..4754aa9 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -222,6 +222,7 @@ static RAMBlock *last_seen_block; static RAMBlock *last_sent_block; static ram_addr_t last_offset; static unsigned long *migration_bitmap; +static QemuMutex migration_bitmap_mutex; static uint64_t migration_dirty_pages; static uint32_t last_version; static bool ram_bulk_stage; @@ -494,6 +495,7 @@ static int save_xbzrle_page(QEMUFile *f, uint8_t **current_data, return 1; } +/* Called with rcu_read_lock() to protect migration_bitmap */ static inline ram_addr_t migration_bitmap_find_and_reset_dirty(MemoryRegion *mr, ram_addr_t start) @@ -502,26 +504,31 @@ ram_addr_t migration_bitmap_find_and_reset_dirty(MemoryRegion *mr, unsigned long nr = base + (start >> TARGET_PAGE_BITS); uint64_t mr_size = TARGET_PAGE_ALIGN(memory_region_size(mr)); unsigned long size = base + (mr_size >> TARGET_PAGE_BITS); + unsigned long *bitmap; unsigned long next; + bitmap = atomic_rcu_read(&migration_bitmap); if (ram_bulk_stage && nr > base) { next = nr + 1; } else { - next = find_next_bit(migration_bitmap, size, nr); + next = find_next_bit(bitmap, size, nr); } if (next < size) { - clear_bit(next, migration_bitmap); + clear_bit(next, bitmap); migration_dirty_pages--; } return (next - base) << TARGET_PAGE_BITS; } +/* Called with rcu_read_lock() to protect migration_bitmap */ static void migration_bitmap_sync_range(ram_addr_t start, ram_addr_t length) { + unsigned long *bitmap; + bitmap = atomic_rcu_read(&migration_bitmap); migration_dirty_pages += - cpu_physical_memory_sync_dirty_bitmap(migration_bitmap, start, length); + cpu_physical_memory_sync_dirty_bitmap(bitmap, start, length); } @@ -1017,10 +1024,15 @@ void free_xbzrle_decoded_buf(void) static void migration_end(void) { - if (migration_bitmap) { + unsigned long *bitmap; + qemu_mutex_lock(&migration_bitmap_mutex); + bitmap = migration_bitmap; + atomic_rcu_set(&migration_bitmap, NULL); + qemu_mutex_unlock(&migration_bitmap_mutex); + if (bitmap) { memory_global_dirty_log_stop(); - g_free(migration_bitmap); - migration_bitmap = NULL; + synchronize_rcu(); + g_free(bitmap); } XBZRLE_cache_lock(); @@ -1067,6 +1079,7 @@ static int ram_save_setup(QEMUFile *f, void *opaque) dirty_rate_high_cnt = 0; bitmap_sync_count = 0; migration_bitmap_sync_init(); + qemu_mutex_init(&migration_bitmap_mutex); if (migrate_use_xbzrle()) { XBZRLE_cache_lock();