From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-m1973196.qiye.163.com (mail-m1973196.qiye.163.com [220.197.31.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6ADA03C4552 for ; Tue, 28 Apr 2026 07:26:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=220.197.31.96 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777361218; cv=none; b=N1mminxPsgq4ao4/JNeye8AU7gnT3EmoE6fLzxsjulY73rTomHJTdoeQG+oUfUsMDJ5akYonhVuLDWrDXdcOjUBrlPHToJ8msVkmXyrr2Pykf21O+OyKjK7+MHMUWFUbDsbey+Rt7PuZAdxY9zskKbUTgKeN+beTZbcPBCko8oQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777361218; c=relaxed/simple; bh=ZNmAacTvlcxUpZTzLgEpNmjctmtoWm1BdY2OZ9tCEZY=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=oR/hLX9GSBA6cy8NoLG/GVctO+hNQ8+mQJk6iGSE6qIe97ugLZuhnWKIs8HmtMXq74EcOS2iqOyYIWys7nGj8g6n5CLzo8TF0rVCaH36nYbSrACJHDgmUDk5APk0tWBItgASiX1a7vrvpjIyTVofdEoN9GU3X5v6ubY1ilIKsVw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=easystack.cn; spf=pass smtp.mailfrom=easystack.cn; arc=none smtp.client-ip=220.197.31.96 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=easystack.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=easystack.cn Received: from localhost.localdomain (unknown [218.94.118.90]) by smtp.qiye.163.com (Hmail) with ESMTP id 197b49307; Tue, 28 Apr 2026 15:11:27 +0800 (GMT+08:00) From: Zhen Ni To: akpm@linux-foundation.org, vbabka@kernel.org Cc: surenb@google.com, mhocko@suse.com, jackmanb@google.com, hannes@cmpxchg.org, ziy@nvidia.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Zhen Ni Subject: [PATCH v3 3/4] mm/page_owner: add NUMA node filter with nodelist support Date: Tue, 28 Apr 2026 15:11:11 +0800 Message-Id: <20260428071112.1420380-4-zhen.ni@easystack.cn> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20260428071112.1420380-1-zhen.ni@easystack.cn> References: <20260428071112.1420380-1-zhen.ni@easystack.cn> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-HM-Tid: 0a9dd2edb8600229kunmb0c223f1156f22 X-HM-MType: 1 X-HM-Spam-Status: e1kfGhgUHx5ZQUpXWQgPGg8OCBgUHx5ZQUlOS1dZFg8aDwILHllBWSg2Ly tZV1koWUFJQjdXWRgWCB1ZQUpXWS1ZQUlXWQ8JGhUIEh9ZQVkaQ09PVhlCH04ZTEwaHRlNSFYVFA kWGhdVGRETFhoSFyQUDg9ZV1kYEgtZQVlJSkNVQk9VSkpDVUJLWVdZFhoPEhUdFFlBWU9LSFVKS0 lPT09IVUpLS1VKQktLWQY+ Add NUMA node filtering functionality to page_owner to allow filtering pages by specific NUMA node(s) using nodelist format. The filter allows users to focus on pages from specific NUMA nodes, which is useful for NUMA-aware memory allocation analysis and debugging. Supported input formats: - Single node: echo "2" > nid - Multiple nodes: echo "0,2,3" > nid - Node range: echo "0-3" > nid - Mixed format: echo "0,2-4,7" > nid - Disable filter: echo "-1" > nid Link: https://lore.kernel.org/linux-mm/20260417154638.22370-4-zhen.ni@easystack.cn/ Link: https://lore.kernel.org/linux-mm/20260419155540.376847-4-zhen.ni@easystack.cn/ Suggested-by: Zi Yan Signed-off-by: Zhen Ni --- Changes in v2: - Use nodemask_t instead of int to support multiple nodes - Implement nodelist_parse() to support flexible input formats * Single node: "0", "2" * Multiple nodes: "0,2,3" * Ranges: "0-3" * Mixed: "0,2-4,7" - Use %*pbl format for output (e.g., "0-2", "0,2-4,7") - Use dynamic memory allocation (kmalloc) to handle variable-length input - Follow cpuset's max_write_len pattern: (100 + 6 * MAX_NUMNODES) Changes in v3: - Remove READ_ONCE/WRITE_ONCE for nodemask_t (fixes compilation errors) * nodemask_t is a large structure (128 bytes) that triggers compile-time asserts * Direct assignment is safe for this use case - Add comment explaining input length calculation formula * 6 bytes = ",NNNNN" (comma + 5-digit node number) - Simplify "-1" check using kstrtoint() instead of dual strcmp() - Move nodemask_t mask read outside PFN iteration loop for performance * Avoids 128-byte structure copy on each iteration --- mm/page_owner.c | 82 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 82 insertions(+) diff --git a/mm/page_owner.c b/mm/page_owner.c index 6d87b6948cfa..e674a374669a 100644 --- a/mm/page_owner.c +++ b/mm/page_owner.c @@ -685,6 +685,7 @@ read_page_owner(struct file *file, char __user *buf, size_t count, loff_t *ppos) struct page_ext *page_ext; struct page_owner *page_owner; depot_stack_handle_t handle; + nodemask_t mask; if (!static_branch_unlikely(&page_owner_inited)) return -EINVAL; @@ -698,6 +699,8 @@ read_page_owner(struct file *file, char __user *buf, size_t count, loff_t *ppos) while (!pfn_valid(pfn) && (pfn & (MAX_ORDER_NR_PAGES - 1)) != 0) pfn++; + mask = owner_filter.nid_mask; + /* Find an allocated page */ for (; pfn < max_pfn; pfn++) { /* @@ -730,6 +733,14 @@ read_page_owner(struct file *file, char __user *buf, size_t count, loff_t *ppos) if (unlikely(!page_ext)) continue; + /* NUMA node filter using bitmask */ + if (!nodes_empty(mask)) { + int nid = page_to_nid(page); + + if (!node_isset(nid, mask)) + goto ext_put_continue; + } + /* * Some pages could be missed by concurrent allocation or free, * because we don't hold the zone lock. @@ -1009,6 +1020,75 @@ DEFINE_SIMPLE_ATTRIBUTE(page_owner_print_mode_fops, &page_owner_print_mode_get, &page_owner_print_mode_set, "%lld"); +static ssize_t nid_filter_write(struct file *file, + const char __user *buf, + size_t count, loff_t *ppos) +{ + char *kbuf; + nodemask_t mask; + int ret; + int val; + + /* + * Limit input size to handle worst-case nodelist (all nodes). + * Worst case per node: ",NNNNN" (comma + 5-digit node number) = 6 bytes. + * Formula: 100 bytes overhead + 6 * MAX_NUMNODES + */ + if (count > (100 + 6 * MAX_NUMNODES)) + return -EINVAL; + + kbuf = kmalloc(count + 1, GFP_KERNEL); + if (!kbuf) + return -ENOMEM; + + if (copy_from_user(kbuf, buf, count)) { + ret = -EFAULT; + goto out_free; + } + kbuf[count] = '\0'; + + /* Support: "-1" to clear, or nodelist format like "0", "0,2", "0-3" */ + if (kstrtoint(kbuf, 10, &val) == 0 && val == -1) + nodes_clear(mask); + else if (nodelist_parse(kbuf, mask)) { + ret = -EINVAL; + goto out_free; + } + + owner_filter.nid_mask = mask; + ret = count; + +out_free: + kfree(kbuf); + return ret; +} + +static int nid_filter_show(struct seq_file *m, void *v) +{ + nodemask_t mask = owner_filter.nid_mask; + + if (nodes_empty(mask)) + seq_puts(m, "-1\n"); + else + seq_printf(m, "%*pbl\n", nodemask_pr_args(&mask)); + + return 0; +} + +static int nid_filter_open(struct inode *inode, struct file *file) +{ + return single_open(file, nid_filter_show, NULL); +} + +static const struct file_operations nid_filter_fops = { + .owner = THIS_MODULE, + .open = nid_filter_open, + .read = seq_read, + .llseek = seq_lseek, + .write = nid_filter_write, + .release = single_release, +}; + static int __init pageowner_init(void) { @@ -1024,6 +1104,8 @@ static int __init pageowner_init(void) filter_dir = debugfs_create_dir("page_owner_filter", NULL); debugfs_create_file("print_mode", 0600, filter_dir, NULL, &page_owner_print_mode_fops); + debugfs_create_file("nid", 0600, filter_dir, NULL, + &nid_filter_fops); dir = debugfs_create_dir("page_owner_stacks", NULL); debugfs_create_file("show_stacks", 0400, dir, -- 2.20.1