From nobody Fri Dec 19 07:31:04 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 80B0EEEAA42 for ; Fri, 15 Sep 2023 02:53:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231821AbjIOCxW (ORCPT ); Thu, 14 Sep 2023 22:53:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44940 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231759AbjIOCxM (ORCPT ); Thu, 14 Sep 2023 22:53:12 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 843B12701 for ; Thu, 14 Sep 2023 19:53:08 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BAF88C433C7; Fri, 15 Sep 2023 02:53:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1694746388; bh=wBwPsUGsJdUgsPRGuDP3t7LM9PStyxdXiFRE+6KpN8o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UNlsCXn2IBMaifeZPCzuHLGLs2hxZKyJo15KTVgqw2yb4GmWro5TL/tfPUSK6bwAq QSOAsTa0LGtwiKWKcmD1j92KgS8dR/UlLaruT1InEnnlxtuvkE5wIM8GnH2+tyScCR HMt5/hYyduUJntyRBoJPQoWIIz97O2i1IEi621u4wpsk80vovp6HWkUWxkTJjc6RjB MZymM9MTewhbrj7bf1/KSdeYXkLuE/8doyfioVpzF8G9iUZWTtpW9qXiCvu+xpL69h an2xvGCqhontwiXgJKZVeoJGDGf/60hYDKC+MCOd7c9xjhhgMRJAHQNtxTeZMy/dlP HM07jOkZBw0Cw== From: SeongJae Park To: Andrew Morton Cc: SeongJae Park , damon@lists.linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH 5/8] mm/damon/core: introduce nr_accesses_bp Date: Fri, 15 Sep 2023 02:52:48 +0000 Message-Id: <20230915025251.72816-6-sj@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230915025251.72816-1-sj@kernel.org> References: <20230915025251.72816-1-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 yet another representation of the access rate of each region, namely nr_accesses_bp. It is just same to the nr_accesses but represents the value in basis point (1 in 10,000), and updated at once in every aggregation interval. That is, moving_accesses_bp is just nr_accesses * 10000. This may seems useless at the moment. However, it will be useful for representing less than one nr_accesses value that will be needed to make moving sum-based nr_accesses. Signed-off-by: SeongJae Park --- include/linux/damon.h | 5 +++++ mm/damon/core-test.h | 5 +++++ mm/damon/core.c | 6 ++++++ 3 files changed, 16 insertions(+) diff --git a/include/linux/damon.h b/include/linux/damon.h index 487a545a11b4..15f24b23c9a0 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -40,6 +40,7 @@ struct damon_addr_range { * @ar: The address range of the region. * @sampling_addr: Address of the sample for the next access check. * @nr_accesses: Access frequency of this region. + * @nr_accesses_bp: @nr_accesses in basis point (0.01%). * @list: List head for siblings. * @age: Age of this region. * @@ -49,6 +50,9 @@ struct damon_addr_range { * not be done with direct access but with the helper function, * damon_update_region_access_rate(). * + * @nr_accesses_bp is another representation of @nr_accesses in basis point + * (1 in 10,000) that updated every aggregation interval. + * * @age is initially zero, increased for each aggregation interval, and re= set * to zero again if the access frequency is significantly changed. If two * regions are merged into a new region, both @nr_accesses and @age of the= new @@ -58,6 +62,7 @@ struct damon_region { struct damon_addr_range ar; unsigned long sampling_addr; unsigned int nr_accesses; + unsigned int nr_accesses_bp; struct list_head list; =20 unsigned int age; diff --git a/mm/damon/core-test.h b/mm/damon/core-test.h index c539f0e8377e..79f1f12e0dd5 100644 --- a/mm/damon/core-test.h +++ b/mm/damon/core-test.h @@ -94,6 +94,7 @@ static void damon_test_aggregate(struct kunit *test) for (ir =3D 0; ir < 3; ir++) { r =3D damon_new_region(saddr[it][ir], eaddr[it][ir]); r->nr_accesses =3D accesses[it][ir]; + r->nr_accesses_bp =3D accesses[it][ir] * 10000; damon_add_region(r, t); } it++; @@ -147,9 +148,11 @@ static void damon_test_merge_two(struct kunit *test) t =3D damon_new_target(); r =3D damon_new_region(0, 100); r->nr_accesses =3D 10; + r->nr_accesses_bp =3D 100000; damon_add_region(r, t); r2 =3D damon_new_region(100, 300); r2->nr_accesses =3D 20; + r2->nr_accesses_bp =3D 200000; damon_add_region(r2, t); =20 damon_merge_two_regions(t, r, r2); @@ -196,6 +199,7 @@ static void damon_test_merge_regions_of(struct kunit *t= est) for (i =3D 0; i < ARRAY_SIZE(sa); i++) { r =3D damon_new_region(sa[i], ea[i]); r->nr_accesses =3D nrs[i]; + r->nr_accesses_bp =3D nrs[i] * 10000; damon_add_region(r, t); } =20 @@ -297,6 +301,7 @@ static void damon_test_update_monitoring_result(struct = kunit *test) struct damon_region *r =3D damon_new_region(3, 7); =20 r->nr_accesses =3D 15; + r->nr_accesses_bp =3D 150000; r->age =3D 20; =20 new_attrs =3D (struct damon_attrs){ diff --git a/mm/damon/core.c b/mm/damon/core.c index b005dc15009f..ce85c00b0a4c 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -128,6 +128,7 @@ struct damon_region *damon_new_region(unsigned long sta= rt, unsigned long end) region->ar.start =3D start; region->ar.end =3D end; region->nr_accesses =3D 0; + region->nr_accesses_bp =3D 0; INIT_LIST_HEAD(®ion->list); =20 region->age =3D 0; @@ -508,6 +509,7 @@ static void damon_update_monitoring_result(struct damon= _region *r, { r->nr_accesses =3D damon_nr_accesses_for_new_attrs(r->nr_accesses, old_attrs, new_attrs); + r->nr_accesses_bp =3D r->nr_accesses * 10000; r->age =3D damon_age_for_new_attrs(r->age, old_attrs, new_attrs); } =20 @@ -1115,6 +1117,7 @@ static void damon_merge_two_regions(struct damon_targ= et *t, =20 l->nr_accesses =3D (l->nr_accesses * sz_l + r->nr_accesses * sz_r) / (sz_l + sz_r); + l->nr_accesses_bp =3D l->nr_accesses * 10000; l->age =3D (l->age * sz_l + r->age * sz_r) / (sz_l + sz_r); l->ar.end =3D r->ar.end; damon_destroy_region(r, t); @@ -1138,6 +1141,8 @@ static void damon_merge_regions_of(struct damon_targe= t *t, unsigned int thres, else r->age++; =20 + r->nr_accesses_bp =3D r->nr_accesses * 10000; + if (prev && prev->ar.end =3D=3D r->ar.start && abs(prev->nr_accesses - r->nr_accesses) <=3D thres && damon_sz_region(prev) + damon_sz_region(r) <=3D sz_limit) @@ -1186,6 +1191,7 @@ static void damon_split_region_at(struct damon_target= *t, =20 new->age =3D r->age; new->last_nr_accesses =3D r->last_nr_accesses; + new->nr_accesses_bp =3D r->nr_accesses_bp; =20 damon_insert_region(new, r, damon_next_region(r), t); } --=20 2.25.1