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 62079ECAAD5 for ; Mon, 5 Sep 2022 03:11:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235980AbiIEDLU (ORCPT ); Sun, 4 Sep 2022 23:11:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56872 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235922AbiIEDKc (ORCPT ); Sun, 4 Sep 2022 23:10:32 -0400 Received: from smtp-out1.suse.de (smtp-out1.suse.de [IPv6:2001:67c:2178:6::1c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4A45E21E18 for ; Sun, 4 Sep 2022 20:10:30 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id A0A4D38628; Mon, 5 Sep 2022 03:10:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1662347429; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=caEWLfqDu+y+boYO54sxVXmuA4zEki6s/GhDf6KoI7g=; b=qerU60J2ja+QkuOEQnOHj7VzwgxB+GreeesUoWr3/T3n2ts0tRYlNWte1CAesoX15Kgiop rIDJ61BB0UpW62TKmlgIPBtMeOCHLFr+u0Uxs0Nfn0nZmc4x7lye0Rrc24Y1lsMe2PoBK5 ZrZb6uoWSWsA8xBm7CmzgYjGFsEUPMU= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1662347429; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=caEWLfqDu+y+boYO54sxVXmuA4zEki6s/GhDf6KoI7g=; b=DHBa2kCPOTm3cEetEvm35ruFVo5yC5vvClo9Bhbdo0+Bzta7ytYXzl3gqtOtbQGk8Ew9il 9aqOs/1A9aTXFkCA== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id EA7CF139F9; Mon, 5 Sep 2022 03:10:28 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id EEGCNqRoFWMeHwAAMHmgww (envelope-from ); Mon, 05 Sep 2022 03:10:28 +0000 From: Oscar Salvador To: Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Michal Hocko , Vlastimil Babka , Eric Dumazet , Waiman Long , Suren Baghdasaryan , Marco Elver , Andrey Konovalov , Alexander Potapenko , Oscar Salvador Subject: [PATCH v2 3/3] mm,page_owner: Filter out stacks by a threshold counter Date: Mon, 5 Sep 2022 05:10:12 +0200 Message-Id: <20220905031012.4450-4-osalvador@suse.de> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220905031012.4450-1-osalvador@suse.de> References: <20220905031012.4450-1-osalvador@suse.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We want to be able to filter out the output on a threshold basis, in this way we can get rid of a lot of noise and focus only on those stacks which have an allegedly high counter. We can control the threshold value by a new file called 'page_owner_threshold', which is 0 by default. Signed-off-by: Oscar Salvador --- include/linux/stackdepot.h | 3 ++- lib/stackdepot.c | 6 +++-- mm/page_owner.c | 51 +++++++++++++++++++++++++++++++++++++- 3 files changed, 56 insertions(+), 4 deletions(-) diff --git a/include/linux/stackdepot.h b/include/linux/stackdepot.h index 19d3f8295df8..742038216cd0 100644 --- a/include/linux/stackdepot.h +++ b/include/linux/stackdepot.h @@ -25,7 +25,8 @@ depot_stack_handle_t __stack_depot_save(unsigned long *entries, gfp_t gfp_flags, bool can_alloc, enum stack_depot_action action); void stack_depot_dec_count(depot_stack_handle_t handle); -int stack_depot_print_stacks_threshold(char *buf, size_t size, loff_t *pos); +int stack_depot_print_stacks_threshold(char *buf, size_t size, loff_t *pos, + unsigned long threshold); /* * Every user of stack depot has to call stack_depot_init() during its own init diff --git a/lib/stackdepot.c b/lib/stackdepot.c index a198b2dbe3fb..a31e882853ab 100644 --- a/lib/stackdepot.c +++ b/lib/stackdepot.c @@ -566,7 +566,8 @@ depot_stack_handle_t stack_depot_save_action(unsigned long *entries, } EXPORT_SYMBOL_GPL(stack_depot_save_action); -int stack_depot_print_stacks_threshold(char *buf, size_t size, loff_t *pos) +int stack_depot_print_stacks_threshold(char *buf, size_t size, loff_t *pos, + unsigned long threshold) { int i = *pos, ret = 0; struct stack_record **stacks, *stack; @@ -585,7 +586,8 @@ int stack_depot_print_stacks_threshold(char *buf, size_t size, loff_t *pos) for (; stack; stack = stack->next) { if (!stack->size || stack->size < 0 || stack->size > size || stack->handle.valid != 1 || - refcount_read(&stack->count) < 1) + refcount_read(&stack->count) < 1 || + refcount_read(&stack->count) < threshold) continue; ret += stack_trace_snprint(buf, size, stack->entries, stack->size, 0); diff --git a/mm/page_owner.c b/mm/page_owner.c index d88e6b4aefa0..5b895d347c5f 100644 --- a/mm/page_owner.c +++ b/mm/page_owner.c @@ -43,6 +43,8 @@ static depot_stack_handle_t early_handle; static void init_early_allocated_pages(void); +static unsigned long threshold; + static int __init early_page_owner_param(char *buf) { int ret = kstrtobool(buf, &page_owner_enabled); @@ -675,7 +677,7 @@ static ssize_t read_page_owner_stacks(struct file *file, char __user *buf, if (!kbuf) return -ENOMEM; - ret += stack_depot_print_stacks_threshold(kbuf, count, pos); + ret += stack_depot_print_stacks_threshold(kbuf, count, pos, threshold); if (copy_to_user(buf, kbuf, ret)) ret = -EFAULT; @@ -683,6 +685,51 @@ static ssize_t read_page_owner_stacks(struct file *file, char __user *buf, return ret; } +static int page_owner_threshold_show(struct seq_file *p, void *v) +{ + seq_printf(p, "%lu\n", threshold); + return 0; +} + +static ssize_t write_page_owner_threshold(struct file *file, const char __user *buf, + size_t count, loff_t *pos) +{ + char *kbuf; + int ret = 0; + + count = min_t(size_t, count, PAGE_SIZE); + kbuf = kmalloc(count, GFP_KERNEL); + if (!kbuf) + return -ENOMEM; + + if (copy_from_user(kbuf, buf, count)) { + ret = -EFAULT; + goto out; + } + + kbuf[count - 1] = '\0'; + + ret = kstrtoul(kbuf, 10, &threshold); + +out: + kfree(kbuf); + return ret ? ret : count; +} + +static int open_page_owner_threshold(struct inode *inode, struct file *file) +{ + return single_open(file, page_owner_threshold_show, NULL); +} + + +static const struct file_operations proc_page_owner_threshold = { + .open = open_page_owner_threshold, + .read = seq_read, + .llseek = seq_lseek, + .write = write_page_owner_threshold, + .release = single_release, +}; + static const struct file_operations proc_page_owner_stacks = { .read = read_page_owner_stacks, }; @@ -702,6 +749,8 @@ static int __init pageowner_init(void) &proc_page_owner_operations); debugfs_create_file("page_owner_stacks", 0400, NULL, NULL, &proc_page_owner_stacks); + debugfs_create_file("page_owner_threshold", 0600, NULL, NULL, + &proc_page_owner_threshold); return 0; } -- 2.35.3