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Tsirkin" , Jason Wang References: <20201012125323.17509-1-david@redhat.com> <20201012125323.17509-3-david@redhat.com> From: David Hildenbrand Organization: Red Hat GmbH Message-ID: <09e63b8a-fb46-c8ae-7512-84b1dd234075@redhat.com> Date: Fri, 16 Oct 2020 11:00:17 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.3.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 15.10.20 22:24, Pankaj Gupta wrote: >> We actually need one byte less (next_mb_id is exclusive, first_mb_id is >> inclusive). Simplify. >> >> Cc: "Michael S. Tsirkin" >> Cc: Jason Wang >> Cc: Pankaj Gupta >> Signed-off-by: David Hildenbrand >> --- >> drivers/virtio/virtio_mem.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c >> index a1f5bf7a571a..670b3faf412d 100644 >> --- a/drivers/virtio/virtio_mem.c >> +++ b/drivers/virtio/virtio_mem.c >> @@ -257,8 +257,8 @@ static enum virtio_mem_mb_state virtio_mem_mb_get_state(struct virtio_mem *vm, >> */ >> static int virtio_mem_mb_state_prepare_next_mb(struct virtio_mem *vm) >> { >> - unsigned long old_bytes = vm->next_mb_id - vm->first_mb_id + 1; >> - unsigned long new_bytes = vm->next_mb_id - vm->first_mb_id + 2; >> + unsigned long old_bytes = vm->next_mb_id - vm->first_mb_id; >> + unsigned long new_bytes = old_bytes + 1; > > Maybe we can avoid new_bytes & old_bytes variables, instead use single > variable. Can later be used with PFN_UP/PFN_DOWN. I'll see if it fits into a single line now - if it does, I'll move it there. Thanks! -- Thanks, David / dhildenb