From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42222) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YxAPg-0000kA-Aw for qemu-devel@nongnu.org; Tue, 26 May 2015 04:40:41 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YxAPb-0000bo-3A for qemu-devel@nongnu.org; Tue, 26 May 2015 04:40:40 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58113) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YxAPa-0000bi-Pr for qemu-devel@nongnu.org; Tue, 26 May 2015 04:40:34 -0400 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (Postfix) with ESMTPS id 6BA1D8E78B for ; Tue, 26 May 2015 08:40:34 +0000 (UTC) Date: Tue, 26 May 2015 16:40:31 +0800 From: Fam Zheng Message-ID: <20150526084031.GL13749@ad.nay.redhat.com> References: <1430152117-100558-1-git-send-email-pbonzini@redhat.com> <1430152117-100558-12-git-send-email-pbonzini@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1430152117-100558-12-git-send-email-pbonzini@redhat.com> Subject: Re: [Qemu-devel] [PATCH 11/29] memory: include DIRTY_MEMORY_MIGRATION in the dirty log mask List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: qemu-devel@nongnu.org, stefanha@redhat.com, mst@redhat.com On Mon, 04/27 18:28, Paolo Bonzini wrote: > The separate handling of DIRTY_MEMORY_MIGRATION, which does not > call log_start/log_stop callbacks when it changes in a region's > dirty logging mask, has caused several bugs. > > One recent example is commit 4cc856f (kvm-all: Sync dirty-bitmap from > kvm before kvm destroy the corresponding dirty_bitmap, 2015-04-02). > Another performance problem is that KVM keeps tracking dirty pages > after a failed live migration, which causes bad performance due to > disallowing huge page mapping. > > This patch removes the root cause of the problem by reporting > DIRTY_MEMORY_MIGRATION changes via log_start and log_stop. > Note that we now have to rebuild the FlatView when global dirty > logging is enabled or disabled; this ensures that log_start and > log_stop callbacks are invoked. > > This will also be used to make the setting of bitmaps conditional. > > Signed-off-by: Paolo Bonzini > --- > memory.c | 18 ++++++++++++++++-- > 1 file changed, 16 insertions(+), 2 deletions(-) > > diff --git a/memory.c b/memory.c > index 1966347..174cd15 100644 > --- a/memory.c > +++ b/memory.c > @@ -537,7 +537,7 @@ static void render_memory_region(FlatView *view, > remain = clip.size; > > fr.mr = mr; > - fr.dirty_log_mask = mr->dirty_log_mask; > + fr.dirty_log_mask = memory_region_get_dirty_log_mask(mr); > fr.romd_mode = mr->romd_mode; > fr.readonly = readonly; > > @@ -1329,7 +1329,11 @@ bool memory_region_is_skip_dump(MemoryRegion *mr) > > uint8_t memory_region_get_dirty_log_mask(MemoryRegion *mr) > { > - return mr->dirty_log_mask; > + uint8_t mask = mr->dirty_log_mask; > + if (global_dirty_log) { > + mask |= (1 << DIRTY_MEMORY_MIGRATION); This is ugly, but I don't know how to do differently. :( > + } > + return mask; > } > > bool memory_region_is_logging(MemoryRegion *mr, uint8_t client) > @@ -1892,10 +1896,20 @@ void memory_global_dirty_log_start(void) > { > global_dirty_log = true; > MEMORY_LISTENER_CALL_GLOBAL(log_global_start, Forward); > + > + /* Refresh DIRTY_LOG_MIGRATION bit. */ > + memory_region_transaction_begin(); > + memory_region_update_pending = true; > + memory_region_transaction_commit(); > } > > void memory_global_dirty_log_stop(void) > { > + /* Refresh DIRTY_LOG_MIGRATION bit. */ > + memory_region_transaction_begin(); > + memory_region_update_pending = true; > + memory_region_transaction_commit(); > + > global_dirty_log = false; Shouldn't this go before memory_region_transaction_begin? Fam