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 743D332E6BD; Sat, 20 Jun 2026 17:23:10 +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=1781976191; cv=none; b=a7JeB9ibppkxBOJMkcz7nrzs1xvERuwvIEhEfrB0u+nBPpeBr4jq8iHKfzsSjAgGhWFURVqmM3KezueuKDFixQq9TPAWivbnN6WL/38udIeVflASMnYPieWnmTDNcOX6b/D71L+IWrsZxg2jIsYO21hAH5V0ML1HjyLHn2RX3dI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781976191; c=relaxed/simple; bh=StZJS8x4LUv8h1L7ZDg1KAq2Bf+sG/tg7ahu7lA0q9w=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=pdeBKW0kf9d2nEp5P6sc9ECjppKzLaizh12n8VIWGjqyRaVZLaTlmZJefHclmFA/jyD9mfZirxe3m+uSkEI0i+XHQ8PIl75vYWPrWVodCGElCBduRgmmfNtQJ72Z8343w7ZtgRFQQ4Pa/Ohr3b85S6Nvkh6DoHh+dRdDvUFOSY4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=L/vk2Zwl; 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="L/vk2Zwl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9CDE31F00ACF; Sat, 20 Jun 2026 17:23:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1781976190; bh=A3RbtE69bByxdhP29KXrthoi8Z7pSsaegAvxhCquZFE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=L/vk2ZwlDmGI/W/mpDtQp9cU6aMHFl1EwT3t32yZv5rgtmnJuTNsVJYSW2RAVeaA7 IZQqQoMQK3rJXD1rBEgiANFF62acHACc3TTeELWr7AjucHjLIjQKDdQsDjcdN6cv3U YoIp67dl7f6C6eRAdqoGsEVjUKccDIGIR1EWc8G7SVRVOmDEePg1QNSuvHwZn27qim 3CZmluttVnUJfuD8UuQ/m/UvvKWpa7BcS6JqI+Q8jV4SgYiX84SzniGwPuRZetyNzV ljeGpT1OzyzAgqefxdeQJ0dwIdXEn+HijU2Dp95Kri8dIqkFLVzle1y/sMQ2UJHgMg p+nZZWJi7OqSg== From: SeongJae Park To: Cc: SeongJae Park , Andrew Morton , damon@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [RFC PATCH v1.1 12/13] mm/damon/core: remove damon_moving_sum() and its unit test Date: Sat, 20 Jun 2026 10:22:42 -0700 Message-ID: <20260620172244.90953-13-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260620172244.90953-1-sj@kernel.org> References: <20260620172244.90953-1-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 damon_moving_sum() is no longer being called for real purpose but its unit test. Testing a function that is not being used for real users makes no sense. Remove the test and the function. Signed-off-by: SeongJae Park --- mm/damon/core.c | 40 ------------------------------------- mm/damon/tests/core-kunit.h | 16 --------------- 2 files changed, 56 deletions(-) diff --git a/mm/damon/core.c b/mm/damon/core.c index 471b58e8e31b9..f96f54a7f178a 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -3720,46 +3720,6 @@ int damon_set_region_system_rams_default(struct damon_target *t, return damon_set_regions(t, &addr_range, 1, min_region_sz); } -/* - * damon_moving_sum() - Calculate an inferred moving sum value. - * @mvsum: Inferred sum of the last @len_window values. - * @nomvsum: Non-moving sum of the last discrete @len_window window values. - * @len_window: The number of last values to take care of. - * @new_value: New value that will be added to the pseudo moving sum. - * - * Moving sum (moving average * window size) is good for handling noise, but - * the cost of keeping past values can be high for arbitrary window size. This - * function implements a lightweight pseudo moving sum function that doesn't - * keep the past window values. - * - * It simply assumes there was no noise in the past, and get the no-noise - * assumed past value to drop from @nomvsum and @len_window. @nomvsum is a - * non-moving sum of the last window. For example, if @len_window is 10 and we - * have 25 values, @nomvsum is the sum of the 11th to 20th values of the 25 - * values. Hence, this function simply drops @nomvsum / @len_window from - * given @mvsum and add @new_value. - * - * For example, if @len_window is 10 and @nomvsum is 50, the last 10 values for - * the last window could be vary, e.g., 0, 10, 0, 10, 0, 10, 0, 0, 0, 20. For - * calculating next moving sum with a new value, we should drop 0 from 50 and - * add the new value. However, this function assumes it got value 5 for each - * of the last ten times. Based on the assumption, when the next value is - * measured, it drops the assumed past value, 5 from the current sum, and add - * the new value to get the updated pseduo-moving average. - * - * This means the value could have errors, but the errors will be disappeared - * for every @len_window aligned calls. For example, if @len_window is 10, the - * pseudo moving sum with 11th value to 19th value would have an error. But - * the sum with 20th value will not have the error. - * - * Return: Pseudo-moving average after getting the @new_value. - */ -static unsigned int damon_moving_sum(unsigned int mvsum, unsigned int nomvsum, - unsigned int len_window, unsigned int new_value) -{ - return mvsum - nomvsum / len_window + new_value; -} - /** * damon_update_region_access_rate() - Update the access rate of a region. * @r: The DAMON region to update for its access check result. diff --git a/mm/damon/tests/core-kunit.h b/mm/damon/tests/core-kunit.h index d1f019ab6fc25..df16cc070eeb0 100644 --- a/mm/damon/tests/core-kunit.h +++ b/mm/damon/tests/core-kunit.h @@ -600,21 +600,6 @@ static void damon_test_set_attrs(struct kunit *test) damon_destroy_ctx(c); } -static void damon_test_moving_sum(struct kunit *test) -{ - unsigned int mvsum = 50000, nomvsum = 50000, len_window = 10; - unsigned int new_values[] = {10000, 0, 10000, 0, 0, 0, 10000, 0, 0, 0}; - unsigned int expects[] = {55000, 50000, 55000, 50000, 45000, 40000, - 45000, 40000, 35000, 30000}; - int i; - - for (i = 0; i < ARRAY_SIZE(new_values); i++) { - mvsum = damon_moving_sum(mvsum, nomvsum, len_window, - new_values[i]); - KUNIT_EXPECT_EQ(test, mvsum, expects[i]); - } -} - static void damon_test_mvsum(struct kunit *test) { unsigned long input_expects[] = { @@ -1516,7 +1501,6 @@ static struct kunit_case damon_test_cases[] = { KUNIT_CASE(damon_test_nr_accesses_to_accesses_bp), KUNIT_CASE(damon_test_update_monitoring_result), KUNIT_CASE(damon_test_set_attrs), - KUNIT_CASE(damon_test_moving_sum), KUNIT_CASE(damon_test_mvsum), KUNIT_CASE(damos_test_new_filter), KUNIT_CASE(damos_test_commit_quota_goal), -- 2.47.3