From patchwork Wed Oct 18 07:14:07 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Christie X-Patchwork-Id: 10013831 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 1EC51603FF for ; Wed, 18 Oct 2017 07:14:32 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 11657285DB for ; Wed, 18 Oct 2017 07:14:32 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0681728790; Wed, 18 Oct 2017 07:14:32 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B498E285DB for ; Wed, 18 Oct 2017 07:14:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762066AbdJRHOa (ORCPT ); Wed, 18 Oct 2017 03:14:30 -0400 Received: from mx1.redhat.com ([209.132.183.28]:49472 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762063AbdJRHO3 (ORCPT ); Wed, 18 Oct 2017 03:14:29 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id DE442883BA; Wed, 18 Oct 2017 07:14:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com DE442883BA Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=mchristi@redhat.com Received: from rh2.redhat.com (ovpn-120-106.rdu2.redhat.com [10.10.120.106]) by smtp.corp.redhat.com (Postfix) with ESMTP id 19D357BA36; Wed, 18 Oct 2017 07:14:27 +0000 (UTC) From: Mike Christie To: lixiubo@cmss.chinamobile.com, target-devel@vger.kernel.org, nab@linux-iscsi.org Cc: Mike Christie Subject: [PATCH 12/17] tcmu: fix free block calculation Date: Wed, 18 Oct 2017 02:14:07 -0500 Message-Id: <1508310852-15366-13-git-send-email-mchristi@redhat.com> In-Reply-To: <1508310852-15366-1-git-send-email-mchristi@redhat.com> References: <1508310852-15366-1-git-send-email-mchristi@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Wed, 18 Oct 2017 07:14:29 +0000 (UTC) Sender: target-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: target-devel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The blocks_left calculation does not account for free blocks between 0 and thresh, so we could be queueing/waiting when there are enough blocks free. This has us add in the blocks between 0 and thresh as well as at the end from thresh to DATA_BLOCK_BITS. Signed-off-by: Mike Christie --- drivers/target/target_core_user.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c index 4aba4f1..6f9646e 100644 --- a/drivers/target/target_core_user.c +++ b/drivers/target/target_core_user.c @@ -675,7 +675,7 @@ static void gather_data_area(struct tcmu_dev *udev, struct tcmu_cmd *cmd, static inline size_t spc_bitmap_free(unsigned long *bitmap, uint32_t thresh) { - return DATA_BLOCK_SIZE * (thresh - bitmap_weight(bitmap, thresh)); + return thresh - bitmap_weight(bitmap, thresh); } /* @@ -715,8 +715,9 @@ static bool is_ring_space_avail(struct tcmu_dev *udev, struct tcmu_cmd *cmd, /* try to check and get the data blocks as needed */ space = spc_bitmap_free(udev->data_bitmap, udev->dbi_thresh); - if (space < data_needed) { - unsigned long blocks_left = DATA_BLOCK_BITS - udev->dbi_thresh; + if ((space * DATA_BLOCK_SIZE) < data_needed) { + unsigned long blocks_left = DATA_BLOCK_BITS - udev->dbi_thresh + + space; unsigned long grow; if (blocks_left < blocks_needed) {