From mboxrd@z Thu Jan 1 00:00:00 1970 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 From: Wei Wang Date: Tue, 11 Dec 2018 16:24:49 +0800 Message-Id: <1544516693-5395-4-git-send-email-wei.w.wang@intel.com> 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> Subject: [Qemu-devel] [PATCH v11 3/7] migration: use bitmap_mutex in migration_bitmap_clear_dirty List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org, virtio-dev@lists.oasis-open.org, mst@redhat.com, quintela@redhat.com, dgilbert@redhat.com, peterx@redhat.com Cc: pbonzini@redhat.com, liliang.opensource@gmail.com, nilal@redhat.com, riel@redhat.com, wei.w.wang@intel.com 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; } -- 1.8.3.1 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: virtio-dev-return-5171-cohuck=redhat.com@lists.oasis-open.org Sender: List-Post: List-Help: List-Unsubscribe: List-Subscribe: Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 42DE4985C81 for ; Tue, 11 Dec 2018 08:57:59 +0000 (UTC) From: Wei Wang Date: Tue, 11 Dec 2018 16:24:49 +0800 Message-Id: <1544516693-5395-4-git-send-email-wei.w.wang@intel.com> 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> Subject: [virtio-dev] [PATCH v11 3/7] migration: use bitmap_mutex in migration_bitmap_clear_dirty To: qemu-devel@nongnu.org, virtio-dev@lists.oasis-open.org, mst@redhat.com, quintela@redhat.com, dgilbert@redhat.com, peterx@redhat.com Cc: pbonzini@redhat.com, liliang.opensource@gmail.com, nilal@redhat.com, riel@redhat.com, wei.w.wang@intel.com List-ID: 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; } -- 1.8.3.1 --------------------------------------------------------------------- To unsubscribe, e-mail: virtio-dev-unsubscribe@lists.oasis-open.org For additional commands, e-mail: virtio-dev-help@lists.oasis-open.org