From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 14FE3C433FE for ; Mon, 21 Feb 2022 12:36:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1358028AbiBUMge (ORCPT ); Mon, 21 Feb 2022 07:36:34 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:51986 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1358044AbiBUMgd (ORCPT ); Mon, 21 Feb 2022 07:36:33 -0500 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D1F6A17ABE; Mon, 21 Feb 2022 04:36:09 -0800 (PST) Received: from kwepemi100009.china.huawei.com (unknown [172.30.72.55]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4K2MDy0MFyz9ssW; Mon, 21 Feb 2022 20:34:26 +0800 (CST) Received: from kwepemm600009.china.huawei.com (7.193.23.164) by kwepemi100009.china.huawei.com (7.221.188.242) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Mon, 21 Feb 2022 20:36:07 +0800 Received: from [10.174.176.73] (10.174.176.73) by kwepemm600009.china.huawei.com (7.193.23.164) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Mon, 21 Feb 2022 20:36:07 +0800 Subject: Re: [PATCH v13 05/12] bcache: bch_nvmpg_free_pages() of the buddy allocator To: Coly Li , CC: , , Jianpeng Ma , Qiaowei Ren , "Christoph Hellwig" , Dan Williams , "Hannes Reinecke" References: <20211212170552.2812-1-colyli@suse.de> <20211212170552.2812-6-colyli@suse.de> From: "yukuai (C)" Message-ID: Date: Mon, 21 Feb 2022 20:36:05 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20211212170552.2812-6-colyli@suse.de> Content-Type: text/plain; charset="gbk"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.174.176.73] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To kwepemm600009.china.huawei.com (7.193.23.164) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-bcache@vger.kernel.org ÔÚ 2021/12/13 1:05, Coly Li дµÀ: > From: Jianpeng Ma > > This patch implements the bch_nvmpg_free_pages() of the buddy allocator. > > The difference between this and page-buddy-free: > it need owner_uuid to free owner allocated pages, and must > persistent after free. > > Signed-off-by: Jianpeng Ma > Co-developed-by: Qiaowei Ren > Signed-off-by: Qiaowei Ren > Cc: Christoph Hellwig > Cc: Dan Williams > Cc: Hannes Reinecke > Cc: Jens Axboe > --- > drivers/md/bcache/nvmpg.c | 164 ++++++++++++++++++++++++++++++++++++-- > drivers/md/bcache/nvmpg.h | 3 + > 2 files changed, 160 insertions(+), 7 deletions(-) > > diff --git a/drivers/md/bcache/nvmpg.c b/drivers/md/bcache/nvmpg.c > index a920779eb548..8ce0c4389b42 100644 > --- a/drivers/md/bcache/nvmpg.c > +++ b/drivers/md/bcache/nvmpg.c > @@ -248,6 +248,57 @@ static int init_nvmpg_set_header(struct bch_nvmpg_ns *ns) > return rc; > } > > +static void __free_space(struct bch_nvmpg_ns *ns, unsigned long nvmpg_offset, > + int order) > +{ > + unsigned long add_pages = (1L << order); > + pgoff_t pgoff; > + struct page *page; > + void *va; > + > + if (nvmpg_offset == 0) { > + pr_err("free pages on offset 0\n"); > + return; > + } > + > + page = bch_nvmpg_va_to_pg(bch_nvmpg_offset_to_ptr(nvmpg_offset)); > + WARN_ON((!page) || (page->private != order)); > + pgoff = page->index; > + > + while (order < BCH_MAX_ORDER - 1) { > + struct page *buddy_page; > + > + pgoff_t buddy_pgoff = pgoff ^ (1L << order); > + pgoff_t parent_pgoff = pgoff & ~(1L << order); > + > + if ((parent_pgoff + (1L << (order + 1)) > ns->pages_total)) > + break; > + > + va = bch_nvmpg_pgoff_to_ptr(ns, buddy_pgoff); > + buddy_page = bch_nvmpg_va_to_pg(va); > + WARN_ON(!buddy_page); > + > + if (PageBuddy(buddy_page) && (buddy_page->private == order)) { > + list_del((struct list_head *)&buddy_page->zone_device_data); > + __ClearPageBuddy(buddy_page); > + pgoff = parent_pgoff; > + order++; > + continue; > + } > + break; > + } > + > + va = bch_nvmpg_pgoff_to_ptr(ns, pgoff); > + page = bch_nvmpg_va_to_pg(va); > + WARN_ON(!page); > + list_add((struct list_head *)&page->zone_device_data, > + &ns->free_area[order]); > + page->index = pgoff; > + set_page_private(page, order); > + __SetPageBuddy(page); > + ns->free += add_pages; > +} > + > static void bch_nvmpg_init_free_space(struct bch_nvmpg_ns *ns) > { > unsigned int start, end, pages; > @@ -261,21 +312,19 @@ static void bch_nvmpg_init_free_space(struct bch_nvmpg_ns *ns) > pages = end - start; > > while (pages) { > - void *addr; > - > for (i = BCH_MAX_ORDER - 1; i >= 0; i--) { > if ((pgoff_start % (1L << i) == 0) && > (pages >= (1L << i))) > break; > } > > - addr = bch_nvmpg_pgoff_to_ptr(ns, pgoff_start); > - page = bch_nvmpg_va_to_pg(addr); > + page = bch_nvmpg_va_to_pg( > + bch_nvmpg_pgoff_to_ptr(ns, pgoff_start)); > set_page_private(page, i); > page->index = pgoff_start; > - __SetPageBuddy(page); > - list_add((struct list_head *)&page->zone_device_data, > - &ns->free_area[i]); > + > + /* In order to update ns->free */ > + __free_space(ns, pgoff_start, i); Hi, While testing this patchset, we found that this is probably wrong, pgoff_start represent page number here, however, __free_space expect this to be page offset. Maybe this should be: __free_space(ns, pgoff_start << PAGE_SHIFT, i); Thanks, Kuai