From nobody Fri Dec 19 07:30:13 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 10BBBC4167B for ; Tue, 5 Dec 2023 02:38:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376443AbjLECiM (ORCPT ); Mon, 4 Dec 2023 21:38:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59268 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346389AbjLECiI (ORCPT ); Mon, 4 Dec 2023 21:38:08 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1621F184 for ; Mon, 4 Dec 2023 18:29:09 -0800 (PST) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4EF36C433C7; Tue, 5 Dec 2023 02:29:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1701743348; bh=E477KEEpVfXYBLYCDBbDHRJITkivLWed5UVr6LwW/WM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jngeDOXKER4A8iR1WtRk2Q+VSSXWfsEjUkLKHDo5gl9pr5B546BF+p4Ih9ogHv/gd 3j69ZEx7YNQra9zB8utvELkTvedAI3ffNHroQG1gcpuQah3zv+sddfG/nNHJn9ou6S V0w2KF3S6nz+YbsqEFzG+OzOZhS4KVVv6Kn1osxhYFIOLBAbQcEh2xNbZeBSZMHLjN rmFPkmKu5dKkqh+PyAVPcNDF0TKhEyCuWIYnRSxwIjfg2tI9e/JnNNypV5nyWeHzks t4LyV4p1qOS8rNrGRHVZ64HFNT8LC3wuXLEBuNYV8ZZfKVtkbe2iA31eO8zza3RRqJ mwHIOcSmOtT0Q== From: SeongJae Park To: Andrew Morton Cc: SeongJae Park , damon@lists.linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/3] samples: add proactive reclamation DAMON sample module Date: Tue, 5 Dec 2023 02:28:58 +0000 Message-Id: <20231205022858.1540-4-sj@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231205022858.1540-1-sj@kernel.org> References: <20231205022858.1540-1-sj@kernel.org> 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" Add a sample DAMON application kernel module, namely damon_sample_prcl. It is same to the one of the example kernel modules that presented at kernel summit 2021 with 10 minutes live coding[1] but updated for the latest DAMON interface. The sample module receives a pid of a process to monitor the access, monitors the access to the virtual address space of the process, find regions that not accessed and proactively reclaim those using DAMOS. [1] https://linuxplumbersconf.org/event/11/contributions/984/ Signed-off-by: SeongJae Park --- samples/damon/Kconfig | 13 ++++ samples/damon/Makefile | 1 + samples/damon/damon_sample_prcl.c | 102 ++++++++++++++++++++++++++++++ 3 files changed, 116 insertions(+) create mode 100644 samples/damon/damon_sample_prcl.c diff --git a/samples/damon/Kconfig b/samples/damon/Kconfig index f8b9a73717f9..459042ce5958 100644 --- a/samples/damon/Kconfig +++ b/samples/damon/Kconfig @@ -14,4 +14,17 @@ config SAMPLE_DAMON_WSSE =20 If unsure, say N. =20 +config SAMPLE_DAMON_PRCL + tristate "DAMON sameple module for access-aware proactive reclamation" + depends on DAMON && DAMON_VADDR + help + This builds DAMON sample module for access-aware proactive + reclamation. + + The module receives pid of a process, monitor access to the virtual + address space of the process, find memory regions that not accessed, + and proactively reclaim the regions. + + If unsure, say N. + endmenu diff --git a/samples/damon/Makefile b/samples/damon/Makefile index 1ace3ad4aff0..509f6a619dc4 100644 --- a/samples/damon/Makefile +++ b/samples/damon/Makefile @@ -1,2 +1,3 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_SAMPLE_DAMON_WSSE) +=3D damon_sample_wsse.o +obj-$(CONFIG_SAMPLE_DAMON_PRCL) +=3D damon_sample_prcl.o diff --git a/samples/damon/damon_sample_prcl.c b/samples/damon/damon_sample= _prcl.c new file mode 100644 index 000000000000..487196f18864 --- /dev/null +++ b/samples/damon/damon_sample_prcl.c @@ -0,0 +1,102 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * proactive reclamation: monitor access pattern of a given process, find + * regiosn that seems not accessed, and proactively page out the regions. + */ + +#define pr_fmt(fmt) "damon_sample_prcl: " fmt + +#include +#include +#include +#include + +static int target_pid __read_mostly; +module_param(target_pid, int, 0600); + +static struct damon_ctx *ctx; +static struct pid *target_pidp; + +static int damon_sample_prcl_after_aggregate(struct damon_ctx *c) +{ + struct damon_target *t; + + damon_for_each_target(t, c) { + struct damon_region *r; + unsigned long wss =3D 0; + + damon_for_each_region(r, t) { + if (r->nr_accesses > 0) + wss +=3D r->ar.end - r->ar.start; + } + pr_info("wss: %lu\n", wss); + } + return 0; +} + +static int __init damon_sample_prcl_init(void) +{ + struct damon_target *target; + struct damos *scheme; + + pr_info("Hello\n"); + + ctx =3D damon_new_ctx(); + if (!ctx) + return -ENOMEM; + if (damon_select_ops(ctx, DAMON_OPS_VADDR)) { + damon_destroy_ctx(ctx); + return -EINVAL; + } + + target =3D damon_new_target(); + if (!target) { + damon_destroy_ctx(ctx); + return -ENOMEM; + } + damon_add_target(ctx, target); + target_pidp =3D find_get_pid(target_pid); + if (!target_pidp) { + damon_destroy_ctx(ctx); + return -EINVAL; + } + target->pid =3D target_pidp; + + ctx->callback.after_aggregation =3D damon_sample_prcl_after_aggregate; + + scheme =3D damon_new_scheme( + &(struct damos_access_pattern) { + .min_sz_region =3D PAGE_SIZE, + .max_sz_region =3D ULONG_MAX, + .min_nr_accesses =3D 0, + .max_nr_accesses =3D 0}, + DAMOS_PAGEOUT, + 0, + &(struct damos_quota){}, + &(struct damos_watermarks){}); + if (!scheme) { + damon_destroy_ctx(ctx); + return -ENOMEM; + } + damon_set_schemes(ctx, &scheme, 1); + + return damon_start(&ctx, 1, true); +} + +static void __exit damon_sample_prcl_exit(void) +{ + pr_info("Goodbye\n"); + if (ctx) { + damon_stop(&ctx, 1); + damon_destroy_ctx(ctx); + } + if (target_pidp) + put_pid(target_pidp); +} + +module_init(damon_sample_prcl_init); +module_exit(damon_sample_prcl_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("SeongJae Park"); +MODULE_DESCRIPTION("DAMON sample module for proactive reclamation"); --=20 2.34.1