From patchwork Tue Nov 28 18:40:29 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Christie X-Patchwork-Id: 10080871 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 DAD74602BC for ; Tue, 28 Nov 2017 18:40:51 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D0A8E29584 for ; Tue, 28 Nov 2017 18:40:51 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C2E162958B; Tue, 28 Nov 2017 18:40:51 +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 597B729584 for ; Tue, 28 Nov 2017 18:40:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753950AbdK1Sku (ORCPT ); Tue, 28 Nov 2017 13:40:50 -0500 Received: from mx1.redhat.com ([209.132.183.28]:42148 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753753AbdK1Skt (ORCPT ); Tue, 28 Nov 2017 13:40:49 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0048EC0587C0; Tue, 28 Nov 2017 18:40:49 +0000 (UTC) Received: from rh2.redhat.com (ovpn-125-222.rdu2.redhat.com [10.10.125.222]) by smtp.corp.redhat.com (Postfix) with ESMTP id 64B12600D1; Tue, 28 Nov 2017 18:40:48 +0000 (UTC) From: Mike Christie To: target-devel@vger.kernel.org, nab@linux-iscsi.org Cc: Mike Christie Subject: [PATCH 03/15] tcmu: split unmap_thread_fn Date: Tue, 28 Nov 2017 12:40:29 -0600 Message-Id: <1511894441-8626-4-git-send-email-mchristi@redhat.com> In-Reply-To: <1511894441-8626-1-git-send-email-mchristi@redhat.com> References: <1511894441-8626-1-git-send-email-mchristi@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Tue, 28 Nov 2017 18:40:49 +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 Separate unmap_thread_fn to make it easier to read. Note: this patch does not fix the bug where we might miss a wake up call. The next patch will fix that. This patch only separates the code into functions. Signed-off-by: Mike Christie --- drivers/target/target_core_user.c | 120 ++++++++++++++++++++++---------------- 1 file changed, 70 insertions(+), 50 deletions(-) diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c index d9fd91e..cab6c72 100644 --- a/drivers/target/target_core_user.c +++ b/drivers/target/target_core_user.c @@ -1973,71 +1973,91 @@ static ssize_t tcmu_emulate_write_cache_store(struct config_item *item, .tb_dev_attrib_attrs = NULL, }; -static int unmap_thread_fn(void *data) + +static void find_free_blocks(void) { struct tcmu_dev *udev; loff_t off; uint32_t start, end, block; - while (!kthread_should_stop()) { - DEFINE_WAIT(__wait); - - prepare_to_wait(&unmap_wait, &__wait, TASK_INTERRUPTIBLE); - schedule(); - finish_wait(&unmap_wait, &__wait); + mutex_lock(&root_udev_mutex); + list_for_each_entry(udev, &root_udev, node) { + mutex_lock(&udev->cmdr_lock); - if (kthread_should_stop()) - break; + /* Try to complete the finished commands first */ + tcmu_handle_completions(udev); - mutex_lock(&root_udev_mutex); - list_for_each_entry(udev, &root_udev, node) { - mutex_lock(&udev->cmdr_lock); + /* Skip the udevs waiting the global pool or in idle */ + if (udev->waiting_global || !udev->dbi_thresh) { + mutex_unlock(&udev->cmdr_lock); + continue; + } - /* Try to complete the finished commands first */ - tcmu_handle_completions(udev); + end = udev->dbi_max + 1; + block = find_last_bit(udev->data_bitmap, end); + if (block == udev->dbi_max) { + /* + * The last bit is dbi_max, so there is + * no need to shrink any blocks. + */ + mutex_unlock(&udev->cmdr_lock); + continue; + } else if (block == end) { + /* The current udev will goto idle state */ + udev->dbi_thresh = start = 0; + udev->dbi_max = 0; + } else { + udev->dbi_thresh = start = block + 1; + udev->dbi_max = block; + } - /* Skip the udevs waiting the global pool or in idle */ - if (udev->waiting_global || !udev->dbi_thresh) { - mutex_unlock(&udev->cmdr_lock); - continue; - } + /* Here will truncate the data area from off */ + off = udev->data_off + start * DATA_BLOCK_SIZE; + unmap_mapping_range(udev->inode->i_mapping, off, 0, 1); - end = udev->dbi_max + 1; - block = find_last_bit(udev->data_bitmap, end); - if (block == udev->dbi_max) { - /* - * The last bit is dbi_max, so there is - * no need to shrink any blocks. - */ - mutex_unlock(&udev->cmdr_lock); - continue; - } else if (block == end) { - /* The current udev will goto idle state */ - udev->dbi_thresh = start = 0; - udev->dbi_max = 0; - } else { - udev->dbi_thresh = start = block + 1; - udev->dbi_max = block; - } + /* Release the block pages */ + tcmu_blocks_release(&udev->data_blocks, start, end); + mutex_unlock(&udev->cmdr_lock); + } + mutex_unlock(&root_udev_mutex); +} - /* Here will truncate the data area from off */ - off = udev->data_off + start * DATA_BLOCK_SIZE; - unmap_mapping_range(udev->inode->i_mapping, off, 0, 1); +static void run_cmdr_queues(void) +{ + struct tcmu_dev *udev; - /* Release the block pages */ - tcmu_blocks_release(&udev->data_blocks, start, end); + /* + * Try to wake up the udevs who are waiting + * for the global data block pool. + */ + mutex_lock(&root_udev_mutex); + list_for_each_entry(udev, &root_udev, node) { + mutex_lock(&udev->cmdr_lock); + if (!udev->waiting_global) { mutex_unlock(&udev->cmdr_lock); + break; } + mutex_unlock(&udev->cmdr_lock); - /* - * Try to wake up the udevs who are waiting - * for the global data pool. - */ - list_for_each_entry(udev, &root_udev, node) { - if (udev->waiting_global) - wake_up(&udev->wait_cmdr); - } - mutex_unlock(&root_udev_mutex); + wake_up(&udev->wait_cmdr); + } + mutex_unlock(&root_udev_mutex); +} + +static int unmap_thread_fn(void *data) +{ + while (!kthread_should_stop()) { + DEFINE_WAIT(__wait); + + prepare_to_wait(&unmap_wait, &__wait, TASK_INTERRUPTIBLE); + schedule(); + finish_wait(&unmap_wait, &__wait); + + if (kthread_should_stop()) + break; + + find_free_blocks(); + run_cmdr_queues(); } return 0;