From nobody Wed Dec 17 10:05:35 2025 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 E1CB4C77B75 for ; Fri, 21 Apr 2023 10:15:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231719AbjDUKPI (ORCPT ); Fri, 21 Apr 2023 06:15:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48760 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231478AbjDUKOm (ORCPT ); Fri, 21 Apr 2023 06:14:42 -0400 Received: from smtp-out2.suse.de (smtp-out2.suse.de [IPv6:2001:67c:2178:6::1d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6A5F1BBA4 for ; Fri, 21 Apr 2023 03:14:41 -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-out2.suse.de (Postfix) with ESMTPS id 1AD021FDDD; Fri, 21 Apr 2023 10:14:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1682072080; 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=MPdsIHAkF3dojDaKePRBYhF7VPy8HOJoJzQ2IPR70Ow=; b=DdqlQbKRzrk0ecb+luhX0blRgkUDuGYm7WDDLDbPi4vbYnYkhLJT1pTwGhsTuvYWAEJqri kt5QbY3sB5G4gVZ9eIoQ6+DLmEsMikliivsd9cqxZT4qwbGlwF7i+ONMsDKtZ/Y2fep0fG 7oIwPv7A4PDhJeFJjeNvR+3jlGc4xXY= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1682072080; 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=MPdsIHAkF3dojDaKePRBYhF7VPy8HOJoJzQ2IPR70Ow=; b=x4vnIpaKeT0Oe6Mjy4yVpvO3QSsS3+iLzk0GjWPcysPnP0FWH94mz8RNdbfDyx1Ki8iouK v40Oc8hZwlD9BJBA== 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 BABC11390E; Fri, 21 Apr 2023 10:14:38 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id UDFAKg5iQmRNaAAAMHmgww (envelope-from ); Fri, 21 Apr 2023 10:14:38 +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 v4 3/3] mm,page_owner: Filter out stacks by a threshold counter Date: Fri, 21 Apr 2023 12:14:15 +0200 Message-Id: <20230421101415.5734-4-osalvador@suse.de> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230421101415.5734-1-osalvador@suse.de> References: <20230421101415.5734-1-osalvador@suse.de> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" 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 | 17 ++++++++++++++++- mm/page_owner.c | 5 +++++ 3 files changed, 24 insertions(+), 1 deletion(-) diff --git a/include/linux/stackdepot.h b/include/linux/stackdepot.h index e1d05d9adcd1..c6b54199ea26 100644 --- a/include/linux/stackdepot.h +++ b/include/linux/stackdepot.h @@ -120,6 +120,9 @@ depot_stack_handle_t stack_depot_save_action(unsigned l= ong *entries, void *stack_start(struct seq_file *m, loff_t *ppos); void *stack_next(struct seq_file *m, void *v, loff_t *ppos); int stack_print(struct seq_file *m, void *v); + +int page_owner_threshold_get(void *data, u64 *val); +int page_owner_threshold_set(void *data, u64 val); #endif =20 /** diff --git a/lib/stackdepot.c b/lib/stackdepot.c index d0a4e6ac0bc9..2f1a41f0ae4f 100644 --- a/lib/stackdepot.c +++ b/lib/stackdepot.c @@ -502,6 +502,9 @@ static struct stack_record *stack_depot_getstack(depot_= stack_handle_t handle) } =20 #ifdef CONFIG_PAGE_OWNER + +static unsigned long page_owner_stack_threshold =3D 0; + void *stack_start(struct seq_file *m, loff_t *ppos) { unsigned long *table =3D m->private; @@ -557,7 +560,7 @@ int stack_print(struct seq_file *m, void *v) =20 if (!stack->size || stack->size < 0 || stack->size > PAGE_SIZE || stack->handle.valid !=3D 1 || - refcount_read(&stack->count) < 1) + refcount_read(&stack->count) < page_owner_stack_threshold) return 0; =20 buf =3D kzalloc(PAGE_SIZE, GFP_KERNEL); @@ -570,6 +573,18 @@ int stack_print(struct seq_file *m, void *v) =20 return 0; } + +int page_owner_threshold_get(void *data, u64 *val) +{ + *val =3D page_owner_stack_threshold; + return 0; +} + +int page_owner_threshold_set(void *data, u64 val) +{ + page_owner_stack_threshold =3D val; + return 0; +} #endif =20 unsigned int stack_depot_fetch(depot_stack_handle_t handle, diff --git a/mm/page_owner.c b/mm/page_owner.c index b191ad1d41f9..daec789b0b50 100644 --- a/mm/page_owner.c +++ b/mm/page_owner.c @@ -743,6 +743,9 @@ const struct file_operations page_owner_stack_operation= s =3D { .release =3D seq_release, }; =20 +DEFINE_SIMPLE_ATTRIBUTE(proc_page_owner_threshold, &page_owner_threshold_g= et, + &page_owner_threshold_set, "%lu"); + static int __init pageowner_init(void) { if (!static_branch_unlikely(&page_owner_inited)) { @@ -755,6 +758,8 @@ static int __init pageowner_init(void) =20 debugfs_create_file("page_owner_stacks", S_IRUSR, NULL, NULL, &page_owner_stack_operations); + debugfs_create_file("page_owner_threshold", 0600, NULL, NULL, + &proc_page_owner_threshold); =20 return 0; } --=20 2.35.3