Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Mon, 15 May 2023 12:52:33 -0400
From:   "Liam R. Howlett" <Liam.Howlett@Oracle.com>
To:     Peng Zhang <zhangpeng.00@bytedance.com>
Cc:     akpm@linux-foundation.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, maple-tree@lists.infradead.org
Subject: Re: [PATCH 02/10] maple_tree: Drop mtree_alloc_{range,rrange}() and
 related functions.
Message-ID: <20230515165233.sssqpxuxzgt77why@revolver>
Mail-Followup-To: "Liam R. Howlett" <Liam.Howlett@Oracle.com>,
        Peng Zhang <zhangpeng.00@bytedance.com>, akpm@linux-foundation.org,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        maple-tree@lists.infradead.org
References: <20230515131757.60035-1-zhangpeng.00@bytedance.com>
 <20230515131757.60035-3-zhangpeng.00@bytedance.com>
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20230515131757.60035-3-zhangpeng.00@bytedance.com>
User-Agent: NeoMutt/20220429
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?pNO6+9EfoZWttY5FOVg+/WRn+NxiZ6NQwGrAqBCEsqlnqEWfp3qfeD71Vg54?=
 =?us-ascii?Q?ldVBimX6eJ2RSN9UiFhZTzjFoYjHSobSt7JIHH4ZsireJiuyeyPhivg7Cw5F?=
 =?us-ascii?Q?xgOJp12Z6Ba0WYdCoX9OctM6Mumap0mdwcb4uZsdTnGsqouEMAxSpOdHPX3V?=
 =?us-ascii?Q?tpCYlHhSBluo3JM6KgCPQTKHc7F22qPnyGdJUK2pTEKTTn9sIwIhPd2K8K9v?=
 =?us-ascii?Q?/C3eUPGMFSqNDk+QTWxMhbHK3v7JgF35cESu+KrWHURz0sfS/8x9np1I3fF9?=
 =?us-ascii?Q?tqk71nqX5z8hx4tW+WBjHlv2Ws71YhvD0FtmRhy2aOwUZCp4TTXBzv0ZzXr+?=
 =?us-ascii?Q?bZ4W27nZdNGlodi58QFguqb6/wLS+zKDT0PL9AHdo+FqQ29H3vwjNOpvWl2H?=
 =?us-ascii?Q?BW700wp6cYs6wKvEpjUxF7XRrnKKIw+FRLrrk7YxDaTOQDLjw7mF3MPXUoRz?=
 =?us-ascii?Q?6hNtnhEVIZahD4QXLRAec3UBos75RhYVDMILarDW0ZuSgr24zMhXph5kqRtI?=
 =?us-ascii?Q?mJBOgJ4+t72QBtDB3LByHNnZjiBvwqaOm/OVAbG4INJelszDLzjiLHl2q5kf?=
 =?us-ascii?Q?auXiAYBwmju/ub91mtU+/XPYTvZ8PMQZ37uQcRx0RPjLNj5y5nrujQEuZG3w?=
 =?us-ascii?Q?LlI/O6+mycQIL1oSkmoU9vbNIDuHD78zxalDY8nQNUBUHOY+/UWjnIpMwmGV?=
 =?us-ascii?Q?XiXaV9PnTDhJZGRkyJzVbaX5gEHKVbBWqob4sB4BlI2hfo4ey8eBQUud8PNC?=
 =?us-ascii?Q?8pIu7b3z9J/ymgwnCuGiUsrUOxExhf+RNcJDMEF9l1OygXCIqNplaaM0Whdm?=
 =?us-ascii?Q?9nhnoIhx/FQo30GFeaGXY83lQbSL1L894SIFdSAM2Po6TOef4+TJSrmXDfbN?=
 =?us-ascii?Q?RTbvlRHcGiJ35k0qFuNxPae3CPqQG/3FPr103YsWShIfdF0hjlmnS5NmFj6U?=
 =?us-ascii?Q?lPI1Pok4CgmrUgxppcV3icFS7i+rwzvJBn8N62N88hqEGgw4rXwA99FGHKXI?=
 =?us-ascii?Q?vjNG5wvkqT5Ga1U1u6Pe5bn0XJm+oJVr12cbbRnH7uU02se7IzQ/btcsdHgx?=
 =?us-ascii?Q?QV6zAwl46qa5HYL8LvKkkehOSlcvOR1fTJxp7iayw6mYaWBW0B9BjErUisNQ?=
 =?us-ascii?Q?MvQJ4HcFO8W7V8H69RW+7FQxmZdNVPvHgfa0t18cEP4PTlS7LBOyXQEqCpg6?=
 =?us-ascii?Q?s4+qZFZUg23IyGDGg8iY1qWIxHCM+VAY9k0rNqvJMZSCcm4CHH4ubysSQyqS?=
 =?us-ascii?Q?Zwwc3Zey2w78gvYJIrhaYD6U7MSBv1VFGApH6DCfLmz2kGvx6gDN456mM5S5?=
 =?us-ascii?Q?VzEA9gKmTlXDdsu8VIQxuy55VlqnmP2lW/4tW8Bf+ef+7eDT8LUIXJP194NJ?=
 =?us-ascii?Q?DYGKX4xmfTjtEFbuB8g+VUYuziClAgIPpKb+m7L/EkVFSnzRtaYfbdOUO5eH?=
 =?us-ascii?Q?8vgiTqjy7rJduA8zkzahxoRgZ6OPzZeFVO0dcfarIAPVjLJr1THRPiPaJxfX?=
 =?us-ascii?Q?hvW6ov96lHI7n0WYYQafg0sdJLt2LtO69ZYzWOwlGIGlOHpqMNuPKwiOF4rK?=
 =?us-ascii?Q?xY4sNI/JRDkz9tXGBfG1QGpWnJvehB7MyR8RH7W69FlDd/UG8bVlhYRGAsqc?=
 =?us-ascii?Q?Eg=3D=3D?=
X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: =?us-ascii?Q?T6+njEY+lrcM5o5l3d2RkiAebn9lvr9vLds9PqZ9IBgebOGFS3ywYvATs3YH?=
 =?us-ascii?Q?airkHs2aeNpRh91+f6jaHNiE1FueOFmDze9YNTPEfeuLm+JbnYB0pXLAG/d9?=
 =?us-ascii?Q?wl2bu3vdE2USok4d0Hq4kHky8BTPg7SpLtiquBxoeui0MR8rE1+ESEx9cC4+?=
 =?us-ascii?Q?34POcek2zhnTfko+VO+eZCYY1t5PGx2lq5nXJ9cC9Y/4wte4ebClJPFzRN5Y?=
 =?us-ascii?Q?/RWSgX9G9Te/q7zoXOZro3czm5CgimWcrXKrPN+oKNinHRa9Sitd2LghvhUl?=
 =?us-ascii?Q?dAwnO3NZweiESVycrg0zBDqBILIHKxMpozlhGsYOe6o3E2DGkxcwokVoFSaz?=
 =?us-ascii?Q?m+XxLf1A/IE1VtgVM+4DLPIuyWvUalB+1FT7C8zAHFu7WEyCTwp55EnYjfMB?=
 =?us-ascii?Q?e4OUKf6JsN7jpIXhlm2eBsuPc+U7rKPCEkCS1AJBbAKVu1ObwTogddxsl08j?=
 =?us-ascii?Q?ArivMzeR3mCNAXnPvg8d/Zy8rQPleuT5+OVWE80dPIKlbrM1KPyMAnYbvvQR?=
 =?us-ascii?Q?GWDYlZ8OyBU+zX85Iy+PscG61BUyJqtVV2827KXa9BHZiRYIEkYw/t+rFDAF?=
 =?us-ascii?Q?MaxJDP5rYiMv/ak4AYgaE1Fi2LZZ4XEgRhcXjyHwPLoPLmKLz/0UuyXrUT0R?=
 =?us-ascii?Q?6jT1cXkU6TnH0KkHp9QFUDzaE1ptLHWNNRG8f/hsE78CH6vB4Ljga1WgNDUJ?=
 =?us-ascii?Q?lMf46BpcFcdX2PZHSo07n/jo1LfkeP5ODS/27SP/+MO+/UbngP1omG82HXb1?=
 =?us-ascii?Q?9slIv6/KoKRELt2tdkr6gty3suTkHMHy1Vb1wbSL5rt5yux5ohV/ZE+JvozM?=
 =?us-ascii?Q?l+hKLh6WyBHRr9XZgEpeyrWlhF0JedOnV5G5oGTsayZxxvBc20pOMdez8oNZ?=
 =?us-ascii?Q?o+EJ6xIvjPPxkBCVMHQpyxWBQBvb6wbYN08SMvXbWhiDvpt9iUawbQNOEK1M?=
X-OriginatorOrg: oracle.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 1054a331-4123-48ff-65af-08db5564c8a4
X-MS-Exchange-CrossTenant-AuthSource: SN6PR10MB3022.namprd10.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 May 2023 16:52:35.5983
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: ExVkadTNy9im0wP1ORy7H2ej7yovFqUewqhIA1hkNgDbBjEKaX4tr641FQspDoaRnAOjNjlBkQfuPbd14waQHA==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN6PR10MB7442
X-Proofpoint-Virus-Version: vendor=baseguard
 engine=ICAP:2.0.254,Aquarius:18.0.957,Hydra:6.0.573,FMLib:17.11.170.22
 definitions=2023-05-15_14,2023-05-05_01,2023-02-09_01
X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxscore=0 phishscore=0 spamscore=0
 bulkscore=0 suspectscore=0 mlxlogscore=999 adultscore=0 malwarescore=0
 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2304280000
 definitions=main-2305150141
X-Proofpoint-GUID: 9oTSpf1eWrtac8YlAz-r-latMkr5SYnu
X-Proofpoint-ORIG-GUID: 9oTSpf1eWrtac8YlAz-r-latMkr5SYnu
X-Spam-Status: No, score=-2.8 required=5.0 tests=BAYES_00,DKIM_SIGNED,
        DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_LOW,
        RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE
        autolearn=ham autolearn_force=no version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
        lindbergh.monkeyblade.net
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

* Peng Zhang <zhangpeng.00@bytedance.com> [230515 09:18]:
> Drop mtree_alloc_{range,rrange}(), mas_{rev_}alloc() and mas_fill_gap().
> mtree_alloc_{range,rrange}() currently have no users and can be easily
> implemented with mas_empty_area{_rev}(). mas_{rev_}alloc() and
> mas_fill_gap() are just their internal functions, drop them together.
> 
> Signed-off-by: Peng Zhang <zhangpeng.00@bytedance.com>

Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>

> ---
>  include/linux/maple_tree.h |   7 --
>  lib/maple_tree.c           | 177 -------------------------------------
>  2 files changed, 184 deletions(-)
> 
> diff --git a/include/linux/maple_tree.h b/include/linux/maple_tree.h
> index 542b09118a09f..3dd6edccf83af 100644
> --- a/include/linux/maple_tree.h
> +++ b/include/linux/maple_tree.h
> @@ -306,13 +306,6 @@ int mtree_insert(struct maple_tree *mt, unsigned long index,
>  		void *entry, gfp_t gfp);
>  int mtree_insert_range(struct maple_tree *mt, unsigned long first,
>  		unsigned long last, void *entry, gfp_t gfp);
> -int mtree_alloc_range(struct maple_tree *mt, unsigned long *startp,
> -		void *entry, unsigned long size, unsigned long min,
> -		unsigned long max, gfp_t gfp);
> -int mtree_alloc_rrange(struct maple_tree *mt, unsigned long *startp,
> -		void *entry, unsigned long size, unsigned long min,
> -		unsigned long max, gfp_t gfp);
> -
>  int mtree_store_range(struct maple_tree *mt, unsigned long first,
>  		      unsigned long last, void *entry, gfp_t gfp);
>  int mtree_store(struct maple_tree *mt, unsigned long index,
> diff --git a/lib/maple_tree.c b/lib/maple_tree.c
> index b37065a6f570d..49dfe81dfa1b6 100644
> --- a/lib/maple_tree.c
> +++ b/lib/maple_tree.c
> @@ -5120,46 +5120,6 @@ static inline void mas_awalk(struct ma_state *mas, unsigned long size)
>  	}
>  }
>  
> -/*
> - * mas_fill_gap() - Fill a located gap with @entry.
> - * @mas: The maple state
> - * @entry: The value to store
> - * @slot: The offset into the node to store the @entry
> - * @size: The size of the entry
> - * @index: The start location
> - */
> -static inline void mas_fill_gap(struct ma_state *mas, void *entry,
> -		unsigned char slot, unsigned long size, unsigned long *index)
> -{
> -	MA_WR_STATE(wr_mas, mas, entry);
> -	unsigned char pslot = mte_parent_slot(mas->node);
> -	struct maple_enode *mn = mas->node;
> -	unsigned long *pivots;
> -	enum maple_type ptype;
> -	/*
> -	 * mas->index is the start address for the search
> -	 *  which may no longer be needed.
> -	 * mas->last is the end address for the search
> -	 */
> -
> -	*index = mas->index;
> -	mas->last = mas->index + size - 1;
> -
> -	/*
> -	 * It is possible that using mas->max and mas->min to correctly
> -	 * calculate the index and last will cause an issue in the gap
> -	 * calculation, so fix the ma_state here
> -	 */
> -	mas_ascend(mas);
> -	ptype = mte_node_type(mas->node);
> -	pivots = ma_pivots(mas_mn(mas), ptype);
> -	mas->max = mas_safe_pivot(mas, pivots, pslot, ptype);
> -	mas->min = mas_safe_min(mas, pivots, pslot);
> -	mas->node = mn;
> -	mas->offset = slot;
> -	mas_wr_store_entry(&wr_mas);
> -}
> -
>  /*
>   * mas_sparse_area() - Internal function.  Return upper or lower limit when
>   * searching for a gap in an empty tree.
> @@ -5307,74 +5267,6 @@ int mas_empty_area_rev(struct ma_state *mas, unsigned long min,
>  }
>  EXPORT_SYMBOL_GPL(mas_empty_area_rev);
>  
> -static inline int mas_alloc(struct ma_state *mas, void *entry,
> -		unsigned long size, unsigned long *index)
> -{
> -	unsigned long min;
> -
> -	mas_start(mas);
> -	if (mas_is_none(mas) || mas_is_ptr(mas)) {
> -		mas_root_expand(mas, entry);
> -		if (mas_is_err(mas))
> -			return xa_err(mas->node);
> -
> -		if (!mas->index)
> -			return mas_pivot(mas, 0);
> -		return mas_pivot(mas, 1);
> -	}
> -
> -	/* Must be walking a tree. */
> -	mas_awalk(mas, size);
> -	if (mas_is_err(mas))
> -		return xa_err(mas->node);
> -
> -	if (mas->offset == MAPLE_NODE_SLOTS)
> -		goto no_gap;
> -
> -	/*
> -	 * At this point, mas->node points to the right node and we have an
> -	 * offset that has a sufficient gap.
> -	 */
> -	min = mas->min;
> -	if (mas->offset)
> -		min = mas_pivot(mas, mas->offset - 1) + 1;
> -
> -	if (mas_is_err(mas))
> -		return xa_err(mas->node);
> -
> -	if (mas->index < min)
> -		mas->index = min;
> -
> -	mas_fill_gap(mas, entry, mas->offset, size, index);
> -	return 0;
> -
> -no_gap:
> -	return -EBUSY;
> -}
> -
> -static inline int mas_rev_alloc(struct ma_state *mas, unsigned long min,
> -				unsigned long max, void *entry,
> -				unsigned long size, unsigned long *index)
> -{
> -	int ret = 0;
> -
> -	ret = mas_empty_area_rev(mas, min, max, size);
> -	if (ret)
> -		return ret;
> -
> -	if (mas_is_err(mas))
> -		return xa_err(mas->node);
> -
> -	if (mas->offset == MAPLE_NODE_SLOTS)
> -		goto no_gap;
> -
> -	mas_fill_gap(mas, entry, mas->offset, size, index);
> -	return 0;
> -
> -no_gap:
> -	return -EBUSY;
> -}
> -
>  /*
>   * mte_dead_leaves() - Mark all leaves of a node as dead.
>   * @mas: The maple state
> @@ -6481,75 +6373,6 @@ int mtree_insert(struct maple_tree *mt, unsigned long index, void *entry,
>  }
>  EXPORT_SYMBOL(mtree_insert);
>  
> -int mtree_alloc_range(struct maple_tree *mt, unsigned long *startp,
> -		void *entry, unsigned long size, unsigned long min,
> -		unsigned long max, gfp_t gfp)
> -{
> -	int ret = 0;
> -
> -	MA_STATE(mas, mt, min, min);
> -	if (!mt_is_alloc(mt))
> -		return -EINVAL;
> -
> -	if (WARN_ON_ONCE(mt_is_reserved(entry)))
> -		return -EINVAL;
> -
> -	if (min > max)
> -		return -EINVAL;
> -
> -	if (max < size)
> -		return -EINVAL;
> -
> -	if (!size)
> -		return -EINVAL;
> -
> -	mtree_lock(mt);
> -retry:
> -	mas.offset = 0;
> -	mas.index = min;
> -	mas.last = max - size + 1;
> -	ret = mas_alloc(&mas, entry, size, startp);
> -	if (mas_nomem(&mas, gfp))
> -		goto retry;
> -
> -	mtree_unlock(mt);
> -	return ret;
> -}
> -EXPORT_SYMBOL(mtree_alloc_range);
> -
> -int mtree_alloc_rrange(struct maple_tree *mt, unsigned long *startp,
> -		void *entry, unsigned long size, unsigned long min,
> -		unsigned long max, gfp_t gfp)
> -{
> -	int ret = 0;
> -
> -	MA_STATE(mas, mt, min, max - size + 1);
> -	if (!mt_is_alloc(mt))
> -		return -EINVAL;
> -
> -	if (WARN_ON_ONCE(mt_is_reserved(entry)))
> -		return -EINVAL;
> -
> -	if (min > max)
> -		return -EINVAL;
> -
> -	if (max < size - 1)
> -		return -EINVAL;
> -
> -	if (!size)
> -		return -EINVAL;
> -
> -	mtree_lock(mt);
> -retry:
> -	ret = mas_rev_alloc(&mas, min, max, entry, size, startp);
> -	if (mas_nomem(&mas, gfp))
> -		goto retry;
> -
> -	mtree_unlock(mt);
> -	return ret;
> -}
> -EXPORT_SYMBOL(mtree_alloc_rrange);
> -
>  /**
>   * mtree_erase() - Find an index and erase the entire range.
>   * @mt: The maple tree
> -- 
> 2.20.1
>