From patchwork Wed May 27 04:01:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Coly Li X-Patchwork-Id: 11571731 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9E04A166C for ; Wed, 27 May 2020 04:03:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 868B4208FE for ; Wed, 27 May 2020 04:03:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726120AbgE0EDW (ORCPT ); Wed, 27 May 2020 00:03:22 -0400 Received: from mx2.suse.de ([195.135.220.15]:57462 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726063AbgE0EDV (ORCPT ); Wed, 27 May 2020 00:03:21 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id AE08DAE2C; Wed, 27 May 2020 04:03:22 +0000 (UTC) From: Coly Li To: axboe@kernel.dk Cc: linux-bcache@vger.kernel.org, linux-block@vger.kernel.org, Coly Li Subject: [PATCH v2 5/5] bcache: configure the asynchronous registertion to be experimental Date: Wed, 27 May 2020 12:01:55 +0800 Message-Id: <20200527040155.43690-6-colyli@suse.de> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200527040155.43690-1-colyli@suse.de> References: <20200527040155.43690-1-colyli@suse.de> MIME-Version: 1.0 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org In order to avoid the experimental async registration interface to be treated as new kernel ABI for common users, this patch makes it as an experimental kernel configure BCACHE_ASYNC_REGISTRAION. This interface is for extreme large cached data situation, to make sure the bcache device can always created without the udev timeout issue. For normal users the async or sync registration does not make difference. In future when we decide to use the asynchronous registration as default behavior, this experimental interface may be removed. Signed-off-by: Coly Li --- drivers/md/bcache/Kconfig | 9 +++++++++ drivers/md/bcache/super.c | 2 ++ 2 files changed, 11 insertions(+) diff --git a/drivers/md/bcache/Kconfig b/drivers/md/bcache/Kconfig index 6dfa653d30db..bf7dd96db9b3 100644 --- a/drivers/md/bcache/Kconfig +++ b/drivers/md/bcache/Kconfig @@ -26,3 +26,12 @@ config BCACHE_CLOSURES_DEBUG Keeps all active closures in a linked list and provides a debugfs interface to list them, which makes it possible to see asynchronous operations that get stuck. + +config BCACHE_ASYNC_REGISTRAION + bool "Asynchronous device registration (EXPERIMENTAL)" + depends on BCACHE + help + Add a sysfs file /sys/fs/bcache/register_async. Writing registering + device path into this file will returns immediately and the real + registration work is handled in kernel work queue in asynchronous + way. diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index b971d8e916d5..f9975c22bf7e 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -2765,7 +2765,9 @@ static int __init bcache_init(void) static const struct attribute *files[] = { &ksysfs_register.attr, &ksysfs_register_quiet.attr, +#ifdef CONFIG_BCACHE_ASYNC_REGISTRAION &ksysfs_register_async.attr, +#endif &ksysfs_pendings_cleanup.attr, NULL };