From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-23.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0D9FEC433B4 for ; Wed, 14 Apr 2021 00:33:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C37DF613BA for ; Wed, 14 Apr 2021 00:33:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348858AbhDNAdf (ORCPT ); Tue, 13 Apr 2021 20:33:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49332 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348320AbhDNAdf (ORCPT ); Tue, 13 Apr 2021 20:33:35 -0400 Received: from mail-io1-xd34.google.com (mail-io1-xd34.google.com [IPv6:2607:f8b0:4864:20::d34]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B014DC061574 for ; Tue, 13 Apr 2021 17:33:14 -0700 (PDT) Received: by mail-io1-xd34.google.com with SMTP id a11so16879542ioo.0 for ; Tue, 13 Apr 2021 17:33:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=ajkY9cSvM0yJXBaUdfH+EY6hPA2iU5BvpjfgTOX51Fk=; b=H/wsEyTwh3fVtfXOc81Q37NwyeheY5mjBR6Uvlzh0UYMnxEHIMGsTJ0qcvbaInhgJc HnnScWvpxipVGxugIaipkfttKD0HHeWYixRsfHtkRfFwOvdX/Qx59YWEFMsNfmBfYz46 oK6GXu998Y3aVddI5gOMlrI+4xxUb2eDbfiAjDgj6leP2emIRJ2HtkhHTFg6qJ1u+WMl sDEs3xJbMDXMtVSqF3Wgs8rsS4sDcXvm4Uvu68+3peKDwmk1VLatWoqzLJSAmMVQlRES YNee2BQVn+nPG7oW/m/0Omix+YMMA+000P7BPmftBVQxL8hfgh76B3nBi4X7B1Vy7cex nH5Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=ajkY9cSvM0yJXBaUdfH+EY6hPA2iU5BvpjfgTOX51Fk=; b=RerAeXgclUKEdOSwlX3RSWRB1B3FEVwQDcmVJPC7+5gGyCnGFMT2/K8cWeslKscIXV pK8IVyam2HmdqRQ7WC6flVWhI+xIvGyDj/aM/zDbrQph1v16jt6pNsirtjfJiLd1XoKp HTPjE8oJ7mU7tw8q72pmf1jDuSI/rqPfmieGcvvECW4mb3EPBjtMPGXQIJccjoe4lJEp cP2bq+HYmPYH5IK0c8riYOU66E6bcNewdPon/mbbW4jq4TluXvvBkLzw6DmnC0IyTe78 PpHfGzusuk/QT2W5R/UyyWS9r7yYAUdIKs+h8vlLJZQ3GyEpDSs1T7MN28PuDNCd3c2R mgUA== X-Gm-Message-State: AOAM531PCZR5200FC3bWaAK9Pr1Bl3phkb3Wv7swpLNtsNKbkHLF7Yay LpYvB/uWFWJRkIUWkd/V2avKFxuEBo5a5AY1Yqg/EA== X-Google-Smtp-Source: ABdhPJwOKqsKv+OAXpb8uIShaFRPB3HxM8MSdwBmCP+iucCaLStLkTNLQ7R4xq+nOGbZ+syDNvZNR+vKp305VmP2cNQ= X-Received: by 2002:a6b:fa14:: with SMTP id p20mr27435380ioh.168.1618360393909; Tue, 13 Apr 2021 17:33:13 -0700 (PDT) MIME-Version: 1.0 References: <20210412190715.555883-1-dlatypov@google.com> In-Reply-To: From: Daniel Latypov Date: Tue, 13 Apr 2021 17:33:02 -0700 Message-ID: Subject: Re: [PATCH v5] lib: add basic KUnit test for lib/math To: David Gow Cc: Andy Shevchenko , Brendan Higgins , Linux Kernel Mailing List , KUnit Development , "open list:KERNEL SELFTEST FRAMEWORK" , Shuah Khan Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org On Mon, Apr 12, 2021 at 11:41 PM David Gow wrote: > > On Tue, Apr 13, 2021 at 3:07 AM Daniel Latypov wrote: > > > > Add basic test coverage for files that don't require any config options: > > * part of math.h (what seem to be the most commonly used macros) > > * gcd.c > > * lcm.c > > * int_sqrt.c > > * reciprocal_div.c > > (Ignored int_pow.c since it's a simple textbook algorithm.) > > > > These tests aren't particularly interesting, but they > > * provide short and simple examples of parameterized tests > > * provide a place to add tests for any new files in this dir > > * are written so adding new test cases to cover edge cases should be easy > > * looking at code coverage, we hit all the branches in the .c files > > > > Signed-off-by: Daniel Latypov > > This looks good to me. A few comments/observations below, but nothing > that I think should actually block this. > > Reviewed-by: David Gow > > -- David > > > --- > > Changes since v4: > > * add in test cases for some math.h macros (abs, round_up/round_down, > > div_round_down/closest) > > * use parameterized testing less to keep things terser > > > > Changes since v3: > > * fix `checkpatch.pl --strict` warnings > > * add test cases for gcd(0,0) and lcm(0,0) > > * minor: don't test both gcd(a,b) and gcd(b,a) when a == b > > > > Changes since v2: mv math_test.c => math_kunit.c > > > > Changes since v1: > > * Rebase and rewrite to use the new parameterized testing support. > > * misc: fix overflow in literal and inline int_sqrt format string. > > * related: commit 1f0e943df68a ("Documentation: kunit: provide guidance > > for testing many inputs") was merged explaining the patterns shown here. > > * there's an in-flight patch to update it for parameterized testing. > > > > v1: https://lore.kernel.org/lkml/20201019224556.3536790-1-dlatypov@google.com/ > > --- > > lib/math/Kconfig | 5 + > > lib/math/Makefile | 2 + > > lib/math/math_kunit.c | 264 ++++++++++++++++++++++++++++++++++++++++++ > > 3 files changed, 271 insertions(+) > > create mode 100644 lib/math/math_kunit.c > > > > diff --git a/lib/math/Kconfig b/lib/math/Kconfig > > index f19bc9734fa7..6ba8680439c1 100644 > > --- a/lib/math/Kconfig > > +++ b/lib/math/Kconfig > > @@ -15,3 +15,8 @@ config PRIME_NUMBERS > > > > config RATIONAL > > bool > > + > > +config MATH_KUNIT_TEST > > + tristate "KUnit test for lib/math" if !KUNIT_ALL_TESTS > > + default KUNIT_ALL_TESTS > > + depends on KUNIT > > This could have a description of the test and KUnit here, as mentioned > in the style guide doc: > https://www.kernel.org/doc/html/latest/dev-tools/kunit/style.html#test-kconfig-entries > > (I think it's sufficiently self explanatory that it's not essential, > but it could be nice to have a more detailed description of the things > being tested than just "lib/math".) > Done. I've left off the details about what the test tests so we have less places to go and update if/when new tests are added. > > diff --git a/lib/math/Makefile b/lib/math/Makefile > > index be6909e943bd..30abb7a8d564 100644 > > --- a/lib/math/Makefile > > +++ b/lib/math/Makefile > > @@ -4,3 +4,5 @@ obj-y += div64.o gcd.o lcm.o int_pow.o int_sqrt.o reciprocal_div.o > > obj-$(CONFIG_CORDIC) += cordic.o > > obj-$(CONFIG_PRIME_NUMBERS) += prime_numbers.o > > obj-$(CONFIG_RATIONAL) += rational.o > > + > > +obj-$(CONFIG_MATH_KUNIT_TEST) += math_kunit.o > > diff --git a/lib/math/math_kunit.c b/lib/math/math_kunit.c > > new file mode 100644 > > index 000000000000..80a087a32884 > > --- /dev/null > > +++ b/lib/math/math_kunit.c > > @@ -0,0 +1,264 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Simple KUnit suite for math helper funcs that are always enabled. > > + * > > + * Copyright (C) 2020, Google LLC. > > + * Author: Daniel Latypov > > + */ > > + > > +#include > > +#include > > +#include > > +#include > > +#include > > + > > +static void abs_test(struct kunit *test) > > +{ > > There's something weird about taking the absolute values of char > literals. I'm not sure if it's better to case integer literals (like > with 'short' below), or keep it as-is. I just thought it was amusing :) Converting it to be like the short test below. > > + KUNIT_EXPECT_EQ(test, abs('\0'), '\0'); > > + KUNIT_EXPECT_EQ(test, abs('a'), 'a'); > > + KUNIT_EXPECT_EQ(test, abs(-'a'), 'a'); > > + > > + /* The expression in the macro is actually promoted to an int. */ > > + KUNIT_EXPECT_EQ(test, abs((short)0), 0); > > + KUNIT_EXPECT_EQ(test, abs((short)42), 42); > > + KUNIT_EXPECT_EQ(test, abs((short)-42), 42); > > + > > + KUNIT_EXPECT_EQ(test, abs(0), 0); > > + KUNIT_EXPECT_EQ(test, abs(42), 42); > > + KUNIT_EXPECT_EQ(test, abs(-42), 42); > > + > > + KUNIT_EXPECT_EQ(test, abs(0L), 0L); > > + KUNIT_EXPECT_EQ(test, abs(42L), 42L); > > + KUNIT_EXPECT_EQ(test, abs(-42L), 42L); > > + > > + KUNIT_EXPECT_EQ(test, abs(0LL), 0LL); > > + KUNIT_EXPECT_EQ(test, abs(42LL), 42LL); > > + KUNIT_EXPECT_EQ(test, abs(-42LL), 42LL); > > + > > + /* Unsigned types get casted to signed. */ > > + KUNIT_EXPECT_EQ(test, abs(0ULL), 0LL); > > + KUNIT_EXPECT_EQ(test, abs(42ULL), 42LL); > > A part of me is curious what the result is for -0x80000000, but I > guess that's not defined, so shouldn't be tested. :-) abs(-42ULL) == 42, but the compiler spits out a warning. > > +} > > + > > +static void int_sqrt_test(struct kunit *test) > > +{ > > + KUNIT_EXPECT_EQ(test, int_sqrt(0UL), 0UL); > > + KUNIT_EXPECT_EQ(test, int_sqrt(1UL), 1UL); > > + KUNIT_EXPECT_EQ(test, int_sqrt(4UL), 2UL); > > + KUNIT_EXPECT_EQ(test, int_sqrt(5UL), 2UL); > > + KUNIT_EXPECT_EQ(test, int_sqrt(8UL), 2UL); > > + KUNIT_EXPECT_EQ(test, int_sqrt(1UL << 30), 1UL << 15); > > +} > > + > > _Maybe_ it's worth a comment here that round_up (and round_down) only > support rounding to powers of two? > (Either that, or also test roundup/rounddown to provide the contrast.) Adding in those test cases for v6. Andy had asked for those as well but I had forgotten them by the time I sent out v5. > > > +static void round_up_test(struct kunit *test) > > +{ > > + KUNIT_EXPECT_EQ(test, round_up(0, 1), 0); > > + KUNIT_EXPECT_EQ(test, round_up(1, 2), 2); > > + KUNIT_EXPECT_EQ(test, round_up(3, 2), 4); > > + KUNIT_EXPECT_EQ(test, round_up((1 << 30) - 1, 2), 1 << 30); > > + KUNIT_EXPECT_EQ(test, round_up((1 << 30) - 1, 1 << 29), 1 << 30); > > +} > > + > > +static void round_down_test(struct kunit *test) > > +{ > > + KUNIT_EXPECT_EQ(test, round_down(0, 1), 0); > > + KUNIT_EXPECT_EQ(test, round_down(1, 2), 0); > > + KUNIT_EXPECT_EQ(test, round_down(3, 2), 2); > > + KUNIT_EXPECT_EQ(test, round_down((1 << 30) - 1, 2), (1 << 30) - 2); > > + KUNIT_EXPECT_EQ(test, round_down((1 << 30) - 1, 1 << 29), 1 << 29); > > +} > > + > > +static void div_round_up_test(struct kunit *test) > > +{ > > + KUNIT_EXPECT_EQ(test, DIV_ROUND_UP(0, 1), 0); > > + KUNIT_EXPECT_EQ(test, DIV_ROUND_UP(20, 10), 2); > > + KUNIT_EXPECT_EQ(test, DIV_ROUND_UP(21, 10), 3); > > + KUNIT_EXPECT_EQ(test, DIV_ROUND_UP(21, 20), 2); > > + KUNIT_EXPECT_EQ(test, DIV_ROUND_UP(21, 99), 1); > > +} > > + > > +static void div_round_closest_test(struct kunit *test) > > +{ > > + KUNIT_EXPECT_EQ(test, DIV_ROUND_CLOSEST(0, 1), 0); > > + KUNIT_EXPECT_EQ(test, DIV_ROUND_CLOSEST(20, 10), 2); > > + KUNIT_EXPECT_EQ(test, DIV_ROUND_CLOSEST(21, 10), 2); > > + KUNIT_EXPECT_EQ(test, DIV_ROUND_CLOSEST(25, 10), 3); > > +} > > + > > +/* Generic test case for unsigned long inputs. */ > > +struct test_case { > > + unsigned long a, b; > > + unsigned long result; > > +}; > > + > > +static struct test_case gcd_cases[] = { > > + { > > + .a = 0, .b = 0, > > + .result = 0, > > + }, > > + { > > + .a = 0, .b = 1, > > + .result = 1, > > + }, > > + { > > + .a = 2, .b = 2, > > + .result = 2, > > + }, > > + { > > + .a = 2, .b = 4, > > + .result = 2, > > + }, > > + { > > + .a = 3, .b = 5, > > + .result = 1, > > + }, > > + { > > + .a = 3 * 9, .b = 3 * 5, > > + .result = 3, > > + }, > > + { > > + .a = 3 * 5 * 7, .b = 3 * 5 * 11, > > + .result = 15, > > + }, > > + { > > + .a = 1 << 21, > > + .b = (1 << 21) - 1, > > + .result = 1, > > + }, > > +}; > > + > > +KUNIT_ARRAY_PARAM(gcd, gcd_cases, NULL); > > + > > +static void gcd_test(struct kunit *test) > > +{ > > + const char *message_fmt = "gcd(%lu, %lu)"; > > + const struct test_case *test_param = test->param_value; > > + > > + KUNIT_EXPECT_EQ_MSG(test, test_param->result, > > + gcd(test_param->a, test_param->b), > > + message_fmt, test_param->a, > > + test_param->b); > > + > > + if (test_param->a == test_param->b) > > + return; > > + > > + /* gcd(a,b) == gcd(b,a) */ > > + KUNIT_EXPECT_EQ_MSG(test, test_param->result, > > + gcd(test_param->b, test_param->a), > > + message_fmt, test_param->b, > > + test_param->a); > > +} > > + > > +static struct test_case lcm_cases[] = { > > + { > > + .a = 0, .b = 0, > > + .result = 0, > > + }, > > + { > > + .a = 0, .b = 1, > > + .result = 0, > > + }, > > + { > > + .a = 1, .b = 2, > > + .result = 2, > > + }, > > + { > > + .a = 2, .b = 2, > > + .result = 2, > > + }, > > + { > > + .a = 3 * 5, .b = 3 * 7, > > + .result = 3 * 5 * 7, > > + }, > > +}; > > + > > +KUNIT_ARRAY_PARAM(lcm, lcm_cases, NULL); > > + > > +static void lcm_test(struct kunit *test) > > +{ > > + const char *message_fmt = "lcm(%lu, %lu)"; > > + const struct test_case *test_param = test->param_value; > > + > > + KUNIT_EXPECT_EQ_MSG(test, test_param->result, > > + lcm(test_param->a, test_param->b), > > + message_fmt, test_param->a, > > + test_param->b); > > + > > + if (test_param->a == test_param->b) > > + return; > > + > > + /* lcm(a,b) == lcm(b,a) */ > > + KUNIT_EXPECT_EQ_MSG(test, test_param->result, > > + lcm(test_param->b, test_param->a), > > + message_fmt, test_param->b, > > + test_param->a); > > +} > > + > > +struct u32_test_case { > > + u32 a, b; > > + u32 result; > > +}; > > + > > +static struct u32_test_case reciprocal_div_cases[] = { > > + { > > + .a = 0, .b = 1, > > + .result = 0, > > + }, > > + { > > + .a = 42, .b = 20, > > + .result = 2, > > + }, > > + { > > + .a = 42, .b = 9999, > > + .result = 0, > > + }, > > + { > > + .a = (1 << 16), .b = (1 << 14), > > + .result = 1 << 2, > > + }, > > +}; > > + > > +KUNIT_ARRAY_PARAM(reciprocal_div, reciprocal_div_cases, NULL); > > Is there a reason this test is using KUNIT_EXPECT_EQ_MSG() rather than > a get_desc function in KUNIT_ARRAY_PARAM()? I can sort-of see how the > former is a little simpler, so I'm not opposed to keeping it as-is, > but it's nice to have KUnit aware of a nicer name for the parameter if > all else is equal. > (I think there's a stronger case for keeping the gcd/lcm tests as is > because they actually have two checks per parameter, but even then, > it's not absurdly silly. And it'd be possible to have both a get_desc > function and use EXPECT_..._MSG() to get the best of both worlds, > albeit with twice as much work.) I can add in the get_desc for it if you want. That's partly a relic of the previous versions of this patchset where I reused the case arrays for the unary funcs as well. But now the unary use case has disappeared and we only need to write one get_desc. But yeah, given it can test two calls of gcd, I've opted to keep it using _MSG(). And I figured I'd keep the reciprocal_div test the same for consistency (aka, I just copy-pasted it from gcd). > > > + > > +static void reciprocal_div_test(struct kunit *test) > > +{ > > + const struct u32_test_case *test_param = test->param_value; > > + struct reciprocal_value rv = reciprocal_value(test_param->b); > > + > > + KUNIT_EXPECT_EQ_MSG(test, test_param->result, > > + reciprocal_divide(test_param->a, rv), > > + "reciprocal_divide(%u, %u)", > > + test_param->a, test_param->b); > > +} > > + > > +static void reciprocal_scale_test(struct kunit *test) > > +{ > > + KUNIT_EXPECT_EQ(test, reciprocal_scale(0u, 100), 0u); > > + KUNIT_EXPECT_EQ(test, reciprocal_scale(1u, 100), 0u); > > + KUNIT_EXPECT_EQ(test, reciprocal_scale(1u << 4, 1 << 28), 1u); > > + KUNIT_EXPECT_EQ(test, reciprocal_scale(1u << 16, 1 << 28), 1u << 12); > > + KUNIT_EXPECT_EQ(test, reciprocal_scale(~0u, 1 << 28), (1u << 28) - 1); > > +} > > + > > +static struct kunit_case math_test_cases[] = { > > + KUNIT_CASE(abs_test), > > + KUNIT_CASE(int_sqrt_test), > > + KUNIT_CASE(round_up_test), > > + KUNIT_CASE(round_down_test), > > + KUNIT_CASE(div_round_up_test), > > + KUNIT_CASE(div_round_closest_test), > > + KUNIT_CASE_PARAM(gcd_test, gcd_gen_params), > > + KUNIT_CASE_PARAM(lcm_test, lcm_gen_params), > > + KUNIT_CASE_PARAM(reciprocal_div_test, reciprocal_div_gen_params), > > + KUNIT_CASE(reciprocal_scale_test), > > + {} > > +}; > > + > > +static struct kunit_suite math_test_suite = { > > + .name = "lib-math", > > + .test_cases = math_test_cases, > > +}; > > + > > +kunit_test_suites(&math_test_suite); > > + > > +MODULE_LICENSE("GPL v2"); > > > > base-commit: 4fa56ad0d12e24df768c98bffe9039f915d1bc02 > > -- > > 2.31.1.295.g9ea45b61b8-goog > >