From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 DD56D2D47E9 for ; Tue, 7 Jul 2026 19:20:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783452019; cv=none; b=IUv+O5+hgJTLwx8P8docQVkJhhJDDLGB8gpWU/Bbc/BhXleuQUS8rw+B2PJ2bO1XfM3oRUUC/52r7ziTWJGf0ZLvVWcY5AAGJZGeEQQLuKPcT0tXcSk3uojHnD0u7R9wdaUReLTtE899TuPlaPxgMAtgfn2jl677JP22rgnl6lE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783452019; c=relaxed/simple; bh=L3AcA5Kts2EJoGwtMICYhoaR/2ETKSqpe1VCwQ8rrrI=; h=Date:To:From:Subject:Message-Id; b=WtxJZVQy9sNS8h01V/Qx0X8DEyWO6z12d5ESgMIEt74158VcDIlsm9P9VDadSbfJ54rCJGGt3/j1Ruxvvs3695nSnRGmh7NykOUW9YQ4z9ELQ1ic8IcqFRFrgsoTmqT3ROX4kEvsrr9yLPNZsF2obgi14OKsZATkYsW7yVKsfRQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=DilSL4LJ; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="DilSL4LJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8BA0E1F000E9; Tue, 7 Jul 2026 19:20:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1783452017; bh=yytq7R/WNoaIVM7aFOtzAynfJwqJA6Tb4M0OL19GDCU=; h=Date:To:From:Subject; b=DilSL4LJpv20dzG4PQWNls0rMN6h+CalcArTQWbq57mMJnFb0v0kj66TIbsQ9XLq5 xQIDURXYjQX12/kTcykyaxQsca/s5vPLnAwK0l7r71uQULc6AH5Agtl9cD+bHPoaWD qt6SzAqdBkA9BC5L9y88laTh8OuXX6Vg+TZujV4k= Date: Tue, 07 Jul 2026 12:20:17 -0700 To: mm-commits@vger.kernel.org,ziy@nvidia.com,vbabka@kernel.org,surenb@google.com,mhocko@suse.com,jackmanb@google.com,hannes@cmpxchg.org,zhen.ni@easystack.cn,akpm@linux-foundation.org From: Andrew Morton Subject: + tools-mm-add-page_owner_filter-userspace-tool.patch added to mm-unstable branch Message-Id: <20260707192017.8BA0E1F000E9@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: tools/mm: add page_owner_filter userspace tool has been added to the -mm mm-unstable branch. Its filename is tools-mm-add-page_owner_filter-userspace-tool.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/tools-mm-add-page_owner_filter-userspace-tool.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via various branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there most days ------------------------------------------------------ From: Zhen Ni Subject: tools/mm: add page_owner_filter userspace tool Date: Tue, 7 Jul 2026 19:54:10 +0800 Add a userspace filtering tool for page_owner that supports per-fd filtering with print_mode and NUMA node filters. Features: - Three print modes: stack (default), handle, stack_handle - NUMA node filtering with flexible formats (single: 0, multiple: 0,1,2, range: 0-3, mixed: 0,2-3) - Per-file-descriptor filter state for independent filtering Usage examples: # Filter by print mode ./page_owner_filter -m handle ./page_owner_filter -m stack_handle # Filter by NUMA node ./page_owner_filter -n 0 ./page_owner_filter -n 0-3 # Combined filters ./page_owner_filter -m stack -n 0,1,2 ./page_owner_filter -m handle -n 0,2-3 The tool validates inputs before sending commands to the kernel and provides clear error messages when the kernel does not support per-fd filtering. Link: https://lore.kernel.org/20260707115411.1714314-4-zhen.ni@easystack.cn Signed-off-by: Zhen Ni Tested-by: Zi Yan Acked-by: Vlastimil Babka (SUSE) Acked-by: Zi Yan Cc: Brendan Jackman Cc: Johannes Weiner Cc: Michal Hocko Cc: Suren Baghdasaryan Signed-off-by: Andrew Morton --- tools/mm/Makefile | 4 tools/mm/page_owner_filter.c | 310 +++++++++++++++++++++++++++++++++ 2 files changed, 312 insertions(+), 2 deletions(-) --- a/tools/mm/Makefile~tools-mm-add-page_owner_filter-userspace-tool +++ a/tools/mm/Makefile @@ -3,7 +3,7 @@ # include ../scripts/Makefile.include -BUILD_TARGETS=page-types slabinfo page_owner_sort thp_swap_allocator_test +BUILD_TARGETS=page-types slabinfo page_owner_sort page_owner_filter thp_swap_allocator_test INSTALL_TARGETS = $(BUILD_TARGETS) thpmaps LIB_DIR = ../lib/api @@ -23,7 +23,7 @@ $(LIBS): $(CC) $(CFLAGS) -o $@ $< $(LDFLAGS) clean: - $(RM) page-types slabinfo page_owner_sort thp_swap_allocator_test + $(RM) page-types slabinfo page_owner_sort page_owner_filter thp_swap_allocator_test make -C $(LIB_DIR) clean sbindir ?= /usr/sbin diff --git a/tools/mm/page_owner_filter.c a/tools/mm/page_owner_filter.c new file mode 100644 --- /dev/null +++ a/tools/mm/page_owner_filter.c @@ -0,0 +1,310 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * User-space helper to filter page_owner output per-fd + * + * Example use: + * ./page_owner_filter -m handle + * ./page_owner_filter -m stack_handle + * ./page_owner_filter -n 0,1,2 + * + * See Documentation/mm/page_owner.rst + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define MAX_CMD_LEN 512 + +static void usage(const char *prog) +{ + fprintf(stderr, "Usage: %s [OPTIONS]\n", prog); + fprintf(stderr, "\nOptions:\n"); + fprintf(stderr, " -m, --mode MODE : print_mode (stack, handle, or stack_handle)\n"); + fprintf(stderr, " -n, --nid NID_LIST : NUMA node IDs (comma-separated or ranges)\n"); + fprintf(stderr, " -o, --output FILE : output file (default: stdout)\n"); + fprintf(stderr, " -h, --help : show this help message\n"); + fprintf(stderr, "\nExamples:\n"); + fprintf(stderr, " %s -m stack\n", prog); + fprintf(stderr, " %s -m handle\n", prog); + fprintf(stderr, " %s -m stack_handle\n", prog); + fprintf(stderr, " %s -m stack -o output.txt\n", prog); + fprintf(stderr, " %s -n 0,1,2\n", prog); + fprintf(stderr, " %s -m stack -n 0\n", prog); +} + +static int validate_mode(const char *mode) +{ + if (strcmp(mode, "stack") == 0 || + strcmp(mode, "handle") == 0 || + strcmp(mode, "stack_handle") == 0) + return 0; + + fprintf(stderr, "Error: Invalid mode '%s'\n", mode); + fprintf(stderr, "Valid modes: stack, handle, stack_handle\n"); + return -1; +} + +static int validate_nid_list(const char *nid_list) +{ + const char *p; + int i = 0; + int has_digit = 0; + int in_range = 0; + int prev_num = 0; + int curr_num = 0; + + if (!nid_list || strlen(nid_list) == 0) + return 0; + + for (p = nid_list; *p; p++) { + if (*p == ',') { + if (!has_digit) { + fprintf(stderr, "Error: Invalid nid_list format\n"); + return -1; + } + if (in_range && prev_num > curr_num) { + fprintf(stderr, + "Error: Invalid range %d-%d (start must be <= end)\n", + prev_num, curr_num); + return -1; + } + i = 0; + has_digit = 0; + in_range = 0; + prev_num = 0; + curr_num = 0; + continue; + } + + if (*p == '-') { + if (!has_digit) { + fprintf(stderr, + "Error: Invalid nid_list format "); + fprintf(stderr, + "(dash without preceding number)\n"); + return -1; + } + if (in_range) { + fprintf(stderr, "Error: Multiple dashes in nid_list\n"); + return -1; + } + prev_num = curr_num; + curr_num = 0; + i = 0; + has_digit = 0; + in_range = 1; + continue; + } + + if (!isdigit((unsigned char)*p)) { + fprintf(stderr, "Error: Invalid character '%c' in nid_list\n", *p); + return -1; + } + + if (i > 5) { + fprintf(stderr, "Error: NID too long (max 65536)\n"); + return -1; + } + curr_num = curr_num * 10 + (*p - '0'); + i++; + has_digit = 1; + } + + if (!has_digit) { + fprintf(stderr, "Error: Invalid nid_list format\n"); + return -1; + } + + if (in_range && prev_num > curr_num) { + fprintf(stderr, + "Error: Invalid range %d-%d (start must be <= end)\n", + prev_num, curr_num); + return -1; + } + + return 0; +} + +int main(int argc, char *argv[]) +{ + const char *output_file = NULL; + char filter_cmd[MAX_CMD_LEN]; + FILE *output = NULL; + int fd = -1; + ssize_t ret; + char buf[4096]; + int opt; + size_t cmd_len = 0; + + signal(SIGPIPE, SIG_IGN); + + static struct option long_options[] = { + {"mode", required_argument, 0, 'm'}, + {"nid", required_argument, 0, 'n'}, + {"output", required_argument, 0, 'o'}, + {"help", no_argument, 0, 'h'}, + {0, 0, 0, 0} + }; + + filter_cmd[0] = '\0'; + + if (argc > 1) { + for (int i = 1; i < argc; i++) { + if (strcmp(argv[i], "-h") == 0 || strcmp(argv[i], "--help") == 0) { + usage(argv[0]); + return 0; + } + } + } + + /* Check if page_owner exists and is readable */ + if (access("/sys/kernel/debug/page_owner", F_OK) != 0) { + if (errno == ENOENT) + fprintf(stderr, "Error: /sys/kernel/debug/page_owner does not exist\n"); + else + perror("Error accessing /sys/kernel/debug/page_owner"); + fprintf(stderr, "Make sure page_owner is enabled in kernel\n"); + return 1; + } + + while ((opt = getopt_long(argc, argv, "m:n:o:h", long_options, NULL)) != -1) { + int len; + + switch (opt) { + case 'm': { + const char *mode = optarg; + + if (validate_mode(mode) < 0) + return 1; + len = snprintf(filter_cmd + cmd_len, MAX_CMD_LEN - cmd_len, + "%smode=%s", cmd_len > 0 ? " " : "", mode); + if (len < 0 || cmd_len + len >= MAX_CMD_LEN) { + fprintf(stderr, "Error: Command too long\n"); + return 1; + } + cmd_len += len; + break; + } + case 'n': { + const char *nid_list = optarg; + + if (validate_nid_list(nid_list) < 0) + return 1; + len = snprintf(filter_cmd + cmd_len, MAX_CMD_LEN - cmd_len, + "%snid=%s", cmd_len > 0 ? " " : "", nid_list); + if (len < 0 || cmd_len + len >= MAX_CMD_LEN) { + fprintf(stderr, "Error: Command too long\n"); + return 1; + } + cmd_len += len; + break; + } + case 'o': + output_file = optarg; + break; + case 'h': + /* Already handled above */ + break; + default: + usage(argv[0]); + return 1; + } + } + + /* At least one filter must be specified */ + if (cmd_len == 0) { + fprintf(stderr, "Error: At least one filter (-m or -n) must be specified\n\n"); + usage(argv[0]); + return 1; + } + + /* Open page_owner for read-write - this will fail if kernel doesn't support write */ + fd = open("/sys/kernel/debug/page_owner", O_RDWR); + if (fd < 0) { + if (errno == EACCES || errno == EPERM) { + fprintf(stderr, "Error: /sys/kernel/debug/page_owner "); + fprintf(stderr, "does not support write access\n"); + fprintf(stderr, "This kernel does not support "); + fprintf(stderr, "per-fd filtering.\n"); + fprintf(stderr, "Please ensure you have a kernel with "); + fprintf(stderr, "per-fd filtering support.\n"); + } else { + perror("Error opening /sys/kernel/debug/page_owner"); + } + return 1; + } + + if (output_file) { + output = fopen(output_file, "w"); + if (!output) { + perror("open output file"); + close(fd); + return 1; + } + } else { + output = stdout; + } + + ret = write(fd, filter_cmd, strlen(filter_cmd)); + + if (ret < 0) { + if (errno == EINVAL) { + fprintf(stderr, "Error: Kernel rejected the filter command.\n"); + fprintf(stderr, "Possible causes:\n"); + fprintf(stderr, " - Kernel does not support per-fd filtering\n"); + fprintf(stderr, " - NUMA node has no memory\n"); + fprintf(stderr, " - Unknown reason\n"); + } else { + perror("write filter command"); + } + goto out; + } + + if ((size_t)ret != strlen(filter_cmd)) + fprintf(stderr, "Warning: Partial write (%zd/%zu)\n", ret, strlen(filter_cmd)); + + /* Read and display filtered output */ + ret = 0; + while ((ret = read(fd, buf, sizeof(buf))) > 0) { + size_t written = fwrite(buf, 1, ret, output); + + if (written != (size_t)ret) { + if (errno == EPIPE) { + /* Pipe closed, treat as success */ + ret = 0; + goto out; + } + perror("write output"); + ret = -1; + goto out; + } + } + + if (ret < 0) { + perror("read page_owner"); + goto out; + } + + if (fflush(output)) { + if (errno == EPIPE) { + /* Pipe closed, treat as success */ + ret = 0; + } else { + perror("flush output"); + ret = -1; + } + } + +out: + close(fd); + if (output != stdout) + fclose(output); + return ret < 0 ? 1 : 0; +} _ Patches currently in -mm which might be from zhen.ni@easystack.cn are mm-page_owner-add-print_mode-filter.patch mm-page_owner-add-numa-node-filter.patch tools-mm-add-page_owner_filter-userspace-tool.patch mm-page_owner-document-page_owner-filter.patch