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 BBEFC265CDD; Sun, 5 Jul 2026 20:57:54 +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=1783285075; cv=none; b=GbFzwr+rvsNT63k0XKUd6sV+WtU4W9a9Zh9WnyQ/eqBw3Z0xDpvukQTDSpA+8JB2AUktEc4jRZEtRKm84RPDvAm5B3WMGbFiykYcgcR5k+35uHzE1ehh1agyvx/tWi7en8IGF13DJKXguzhULQ2BHmbgq7cbXTIIjzz4/v20HWM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783285075; c=relaxed/simple; bh=Oijb/VRXjah1nMArgNjWjULNdaSTTgNNIu0vr3yHjUk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=J5yPCVZDRCaZUA1deYJtCFqyrH0Ub90SRG73CJq3iThLD+HQ0GLEATH7qCd1uN7/UG1Lg39ReLuawCzEH5pMQG5duEtVY98yhO9i1Inc1zHT0DvBnQ+JneyLnb10uKJESCK1qL/C2neXkUEiDrduploksUDVmu2ji+hlaUdKsdI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=K7T23N2r; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="K7T23N2r" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5EF341F00A3E; Sun, 5 Jul 2026 20:57:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783285074; bh=7ea4i8Dv0CoJkmGdBeb8J00MLK5gjFTil2XSf1WpbBk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=K7T23N2r1WUdhw6SQgrU+YiIab7SEZgfNIAuf1MuNya6JXnVyZAULGYW6wYNuk14e 9b2M+08a6V9izNVw93MHqqL9Z8pbdQRYTdDrowDiOVCUtuB8Dtet0mCcPerCQBtBWc 2dFjQqhEtFbYDtmkJpeJ0rIrBkfQo6Tzmu+qIOa6TcWYLxma4m3KN2ncWxfXZTiWNx 4f+EBJv5wls0bdCTKKLPV/GwtxSG+Jali7Epik1aTWHrpXfi25DJdAYo1lqSbxxYOD pRelZaXsVKDvLNncTLGUVcaFkdlN0bXn+xqxuqY+6IGkjUopldP0KmAvy6YebuFkWq ND3uGTd5BQ3pA== From: SJ Park To: Cc: SJ Park , Andrew Morton , damon@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [RFC PATCH 04/16] mm/damon/core: ask apply_probe() to return max probe hits weighted sum Date: Sun, 5 Jul 2026 13:57:26 -0700 Message-ID: <20260705205743.98656-5-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260705205743.98656-1-sj@kernel.org> References: <20260705205743.98656-1-sj@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit check_accesses() DAMON ops callback returns the maximum nr_accesses of regions. DAMON core uses it to calculate a reasonable region merge threshold. The core will need to adjust regions for not nr_accesses but probe hits weighted sum in future. For that, the core needs to know the maximum weighted sum of the regions. Update the protocol for the task. Signed-off-by: SJ Park --- include/linux/damon.h | 7 +++++-- mm/damon/core.c | 2 +- mm/damon/paddr.c | 4 +++- 3 files changed, 9 insertions(+), 4 deletions(-) diff --git a/include/linux/damon.h b/include/linux/damon.h index 4dec5d314c782..62caa67a3c40c 100644 --- a/include/linux/damon.h +++ b/include/linux/damon.h @@ -648,7 +648,9 @@ enum damon_ops_id { * of its update. The value will be used for regions adjustment threshold. * @apply_probes should apply the data attribute probes to each region and * accordingly update the probe hits counter of the region. It should also - * &set sampling_addr or each region if &set_samples is true. + * &set sampling_addr or each region if &set_samples is true. It should also + * return maximum probe hits weighted sum of regions if &return_max_wsum is + * true. * @get_scheme_score should return the priority score of a region for a scheme * as an integer in [0, &DAMOS_MAX_SCORE]. * @apply_scheme is called from @kdamond when a region for user provided @@ -666,7 +668,8 @@ struct damon_operations { void (*update)(struct damon_ctx *context); void (*prepare_access_checks)(struct damon_ctx *context); unsigned int (*check_accesses)(struct damon_ctx *context); - void (*apply_probes)(struct damon_ctx *context, bool set_samples); + unsigned int (*apply_probes)(struct damon_ctx *context, + bool set_samples, bool return_max_wsum); int (*get_scheme_score)(struct damon_ctx *context, struct damon_region *r, struct damos *scheme); unsigned long (*apply_scheme)(struct damon_ctx *context, diff --git a/mm/damon/core.c b/mm/damon/core.c index 7c0184cb78a50..e42f512d87a11 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -3675,7 +3675,7 @@ static int kdamond_fn(void *data) if (ctx->ops.check_accesses) max_nr_accesses = ctx->ops.check_accesses(ctx); if (ctx->ops.apply_probes) - ctx->ops.apply_probes(ctx, false); + ctx->ops.apply_probes(ctx, false, false); if (time_after_eq(ctx->passed_sample_intervals, next_aggregation_sis)) { diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c index ff4fcca949660..3eba3564a31fc 100644 --- a/mm/damon/paddr.c +++ b/mm/damon/paddr.c @@ -166,7 +166,8 @@ static bool damon_pa_filter_pass(phys_addr_t pa, struct folio *folio, return pass; } -static void damon_pa_apply_probes(struct damon_ctx *ctx, bool set_samples) +static unsigned int damon_pa_apply_probes(struct damon_ctx *ctx, + bool set_samples, bool return_max_wsum) { struct damon_target *t; struct damon_region *r; @@ -194,6 +195,7 @@ static void damon_pa_apply_probes(struct damon_ctx *ctx, bool set_samples) folio_put(folio); } } + return 0; } /* -- 2.47.3