From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36975) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fb9Pm-0002c9-3y for qemu-devel@nongnu.org; Thu, 05 Jul 2018 14:55:38 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fb9Pl-0008Qo-Fp for qemu-devel@nongnu.org; Thu, 05 Jul 2018 14:55:38 -0400 References: <20180703105305.45398-1-vsementsov@virtuozzo.com> <20180703105305.45398-2-vsementsov@virtuozzo.com> From: Eric Blake Message-ID: <41a9ce0d-fae5-1f6b-8492-0e64feda4d68@redhat.com> Date: Thu, 5 Jul 2018 13:55:27 -0500 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 1/2] drity-bitmap: refactor merge: separte can_merge List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: John Snow , Vladimir Sementsov-Ogievskiy , qemu-devel@nongnu.org, qemu-block@nongnu.org Cc: kwolf@redhat.com, den@openvz.org, famz@redhat.com, armbru@redhat.com, mreitz@redhat.com On 07/05/2018 01:51 PM, John Snow wrote: > >> - assert(!bdrv_dirty_bitmap_readonly(dest)); >> - >> - if (!hbitmap_merge(dest->bitmap, src->bitmap)) { >> - error_setg(errp, "Bitmaps are incompatible and can't be merged"); >> + if (bdrv_can_merge_dirty_bitmap(dest, src, errp)) { >> + bool ret = hbitmap_merge(dest->bitmap, src->bitmap); >> + assert(ret); > > Might as well just assert(hbitmap_merge(...)); Except that side effects inside assert() are bad programming practice, even if in qemu assert()s are guaranteed to always be enabled by osdep.h. -- Eric Blake, Principal Software Engineer Red Hat, Inc. +1-919-301-3266 Virtualization: qemu.org | libvirt.org