From patchwork Mon Sep 2 07:21:32 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: alexs@kernel.org X-Patchwork-Id: 13786852 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id B0710CA0ED3 for ; Mon, 2 Sep 2024 07:17:50 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3C1C78D0096; Mon, 2 Sep 2024 03:17:50 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 349866B00DB; Mon, 2 Sep 2024 03:17:50 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1C4868D0096; Mon, 2 Sep 2024 03:17:50 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id D3D1D6B00D9 for ; Mon, 2 Sep 2024 03:17:48 -0400 (EDT) Received: from smtpin16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 919B2161A99 for ; Mon, 2 Sep 2024 07:17:48 +0000 (UTC) X-FDA: 82518943416.16.EFB489F Received: from nyc.source.kernel.org (nyc.source.kernel.org [147.75.193.91]) by imf18.hostedemail.com (Postfix) with ESMTP id EEB1E1C000F for ; Mon, 2 Sep 2024 07:17:46 +0000 (UTC) Authentication-Results: imf18.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=luyybGbQ; spf=pass (imf18.hostedemail.com: domain of alexs@kernel.org designates 147.75.193.91 as permitted sender) smtp.mailfrom=alexs@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1725261444; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=cnSV+hbwD6b1KIQGP3skQkvHv4Q6qbPV3pqxOakahcQ=; b=0GzfKqshWV1NAjASWjUExEL+WHHjDF7ddYl23lYHu2KjmuKZjjLAFn5FQKHSB08T3Ja0T0 GeiWbrFzS/b50zLVn9olIVnhBJyMOK7w9zmJAlU0eEHbtIwQHPITvfaokPHEG4u22TNt+x QTqnIy1y5S4JmLwOWTlgRv9P9QGTKiM= ARC-Authentication-Results: i=1; imf18.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=luyybGbQ; spf=pass (imf18.hostedemail.com: domain of alexs@kernel.org designates 147.75.193.91 as permitted sender) smtp.mailfrom=alexs@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1725261444; a=rsa-sha256; cv=none; b=ExSjfn8VdX4P8s7bxCnQTpuOVa8vYNWeS1bJskeSCJYJF4j4gjwYu+n4dTSi3xoI1gAzdV OnqcSx9hxy4OiE1dBdNdArZp0S13ixfO5cboTBXXaFGY8qY7FQVa5/RZKxUuAGjSNL6jDz dES+mmjgpekQAtVIjydnI5gjMAMD404= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id 33F00A4174D; Mon, 2 Sep 2024 07:17:39 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1060BC4CEC2; Mon, 2 Sep 2024 07:17:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725261466; bh=8NP5E97AtP/kem4IUjjLi+FAumtWmwCjNYRbQZ4Zmwk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=luyybGbQP4t9sYIyrJgDKuirEOXTx1BKnq3ONcswGeFiP+L0aMFR8Iec24a+I+X6u DrKhRpC/OLMgaJziuSmQlKpnzOYKyvR/Vh1yQ7aDSjErHfjApKkVdb/q/2ag0XSK/B chTwLoZUDipz8l1hXp7+h3YMah7dJUleabEjOxfGT3ru9pVV5+oNWZ8b0EElUFt3q3 ZcD8H2E6p/WxIAyU7fXdmEmIjqSnXdOZHhVx6nBIht4bV2himfEqtGPEx2/cx23eoq is6MR0afprQ7E1x9B9EySSyJw7/VDVGw+49zdYW7k/vImFfc7UupAym3vgCuVPrMtk pjSj/AX+ltH6w== From: alexs@kernel.org To: Vitaly Wool , Miaohe Lin , Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, minchan@kernel.org, willy@infradead.org, senozhatsky@chromium.org, david@redhat.com, 42.hyeyoo@gmail.com, Yosry Ahmed , nphamcs@gmail.com Cc: Alex Shi Subject: [PATCH v7 21/21] mm/zsmalloc: update comments for page->zpdesc changes Date: Mon, 2 Sep 2024 15:21:32 +0800 Message-ID: <20240902072136.578720-22-alexs@kernel.org> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240902072136.578720-1-alexs@kernel.org> References: <20240902072136.578720-1-alexs@kernel.org> MIME-Version: 1.0 X-Rspam-User: X-Stat-Signature: 5f33d7otopat769d1jn3gjsz4fjoqjtx X-Rspamd-Queue-Id: EEB1E1C000F X-Rspamd-Server: rspam11 X-HE-Tag: 1725261466-468259 X-HE-Meta: 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 qWhLoH28 OvnYCTEC/5jIdUka3rUzh7MRBuGSB+pmHTyeOHBgoQxWIcwdbQX7GfFydmYFti1UNySHNkfZ3K3FNSaMspqcvDKLf+QpDwZ97OKy7Y/8gYS6TboDappoPfUZ37CarsnYM4dYB/L7DVD0RqUBtEwQ3a+vHHwDHvikltdVOKaQsRXXLnQH0FfwaYyjGEifiYP0vvdZvpYfODlTC5I+XkWctRA04EPTei+oj9QnCSIRCITdTrdXi4oJ+NuiS7CtnXFSGLp9V0nATgfBIhf4KiYcvIfI0iVgnI29PX3lZhpc8ATdLtwnYJ6BYeoyb0g== 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: List-Subscribe: List-Unsubscribe: From: Alex Shi After the page to zpdesc conversion, there still left few comments or function named with page not zpdesc, let's update the comments and rename function create_page_chain() as create_zpdesc_chain(). Signed-off-by: Alex Shi --- mm/zsmalloc.c | 61 ++++++++++++++++++++++++++------------------------- 1 file changed, 31 insertions(+), 30 deletions(-) diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index 849f192d4937..1e47cda05c83 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -13,20 +13,19 @@ /* * Following is how we use various fields and flags of underlying - * struct page(s) to form a zspage. + * struct zpdesc(page) to form a zspage. * - * Usage of struct page fields: - * page->private: points to zspage - * page->index: links together all component pages of a zspage + * Usage of struct zpdesc fields: + * zpdesc->zspage: points to zspage + * zpdesc->next: links together all component zpdescs of a zspage * For the huge page, this is always 0, so we use this field * to store handle. - * page->page_type: PGTY_zsmalloc, lower 24 bits locate the first object - * offset in a subpage of a zspage - * - * Usage of struct page flags: - * PG_private: identifies the first component page - * PG_owner_priv_1: identifies the huge component page + * zpdesc->first_obj_offset: PGTY_zsmalloc, lower 24 bits locate the first + * object offset in a subpage of a zspage * + * Usage of struct zpdesc(page) flags: + * PG_private: identifies the first component zpdesc + * PG_lock: lock all component zpdescs for a zspage free, serialize with */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt @@ -191,7 +190,10 @@ struct size_class { */ int size; int objs_per_zspage; - /* Number of PAGE_SIZE sized pages to combine to form a 'zspage' */ + /* + * Number of PAGE_SIZE sized zpdescs/pages to combine to + * form a 'zspage' + */ int pages_per_zspage; unsigned int index; @@ -900,7 +902,7 @@ static void free_zspage(struct zs_pool *pool, struct size_class *class, /* * Since zs_free couldn't be sleepable, this function cannot call - * lock_page. The page locks trylock_zspage got will be released + * lock_page. The zpdesc locks trylock_zspage got will be released * by __free_zspage. */ if (!trylock_zspage(zspage)) { @@ -957,7 +959,7 @@ static void init_zspage(struct size_class *class, struct zspage *zspage) set_freeobj(zspage, 0); } -static void create_page_chain(struct size_class *class, struct zspage *zspage, +static void create_zpdesc_chain(struct size_class *class, struct zspage *zspage, struct zpdesc *zpdescs[]) { int i; @@ -966,9 +968,9 @@ static void create_page_chain(struct size_class *class, struct zspage *zspage, int nr_zpdescs = class->pages_per_zspage; /* - * Allocate individual pages and link them together as: - * 1. all pages are linked together using zpdesc->next - * 2. each sub-page point to zspage using zpdesc->zspage + * Allocate individual zpdescs and link them together as: + * 1. all zpdescs are linked together using zpdesc->next + * 2. each sub-zpdesc point to zspage using zpdesc->zspage * * we set PG_private to identify the first zpdesc (i.e. no other zpdesc * has this flag set). @@ -1026,7 +1028,7 @@ static struct zspage *alloc_zspage(struct zs_pool *pool, zpdescs[i] = zpdesc; } - create_page_chain(class, zspage, zpdescs); + create_zpdesc_chain(class, zspage, zpdescs); init_zspage(class, zspage); zspage->pool = pool; zspage->class = class->index; @@ -1353,7 +1355,7 @@ static unsigned long obj_malloc(struct zs_pool *pool, /* record handle in the header of allocated chunk */ link->handle = handle | OBJ_ALLOCATED_TAG; else - /* record handle to page->index */ + /* record handle to zpdesc->handle */ zspage->first_zpdesc->handle = handle | OBJ_ALLOCATED_TAG; kunmap_atomic(vaddr); @@ -1443,7 +1445,6 @@ static void obj_free(int class_size, unsigned long obj) unsigned int f_objidx; void *vaddr; - obj_to_location(obj, &f_zpdesc, &f_objidx); f_offset = offset_in_page(class_size * f_objidx); zspage = get_zspage(f_zpdesc); @@ -1686,19 +1687,19 @@ static int putback_zspage(struct size_class *class, struct zspage *zspage) #ifdef CONFIG_COMPACTION /* * To prevent zspage destroy during migration, zspage freeing should - * hold locks of all pages in the zspage. + * hold locks of all component zpdesc in the zspage. */ static void lock_zspage(struct zspage *zspage) { struct zpdesc *curr_zpdesc, *zpdesc; /* - * Pages we haven't locked yet can be migrated off the list while we're + * Zpdesc we haven't locked yet can be migrated off the list while we're * trying to lock them, so we need to be careful and only attempt to - * lock each page under migrate_read_lock(). Otherwise, the page we lock - * may no longer belong to the zspage. This means that we may wait for - * the wrong page to unlock, so we must take a reference to the page - * prior to waiting for it to unlock outside migrate_read_lock(). + * lock each zpdesc under migrate_read_lock(). Otherwise, the zpdesc we + * lock may no longer belong to the zspage. This means that we may wait + * for the wrong zpdesc to unlock, so we must take a reference to the + * zpdesc prior to waiting for it to unlock outside migrate_read_lock(). */ while (1) { migrate_read_lock(zspage); @@ -1773,7 +1774,7 @@ static void replace_sub_page(struct size_class *class, struct zspage *zspage, idx++; } while ((zpdesc = get_next_zpdesc(zpdesc)) != NULL); - create_page_chain(class, zspage, zpdescs); + create_zpdesc_chain(class, zspage, zpdescs); first_obj_offset = get_first_obj_offset(oldzpdesc); set_first_obj_offset(newzpdesc, first_obj_offset); if (unlikely(ZsHugePage(zspage))) @@ -1784,8 +1785,8 @@ static void replace_sub_page(struct size_class *class, struct zspage *zspage, static bool zs_page_isolate(struct page *page, isolate_mode_t mode) { /* - * Page is locked so zspage couldn't be destroyed. For detail, look at - * lock_zspage in free_zspage. + * Page/zpdesc is locked so zspage couldn't be destroyed. For detail, + * look at lock_zspage in free_zspage. */ VM_BUG_ON_PAGE(PageIsolated(page), page); @@ -1812,7 +1813,7 @@ static int zs_page_migrate(struct page *newpage, struct page *page, /* We're committed, tell the world that this is a Zsmalloc page. */ __zpdesc_set_zsmalloc(newzpdesc); - /* The page is locked, so this pointer must remain valid */ + /* The zpdesc/page is locked, so this pointer must remain valid */ zspage = get_zspage(zpdesc); pool = zspage->pool; @@ -1885,7 +1886,7 @@ static const struct movable_operations zsmalloc_mops = { }; /* - * Caller should hold page_lock of all pages in the zspage + * Caller should hold zpdesc locks of all in the zspage * In here, we cannot use zspage meta data. */ static void async_free_zspage(struct work_struct *work)