From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout-p-201.mailbox.org (mout-p-201.mailbox.org [80.241.56.171]) (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 C633D31E830; Sat, 1 Aug 2026 11:01:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=80.241.56.171 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785582071; cv=none; b=dLk7F15I91eSfzVGMl6ildzzomuyeiQ6QqyTw/diRGvXGRysDD6Sso8wZgmq6OJ+Jm8w1zs7CmjP8KPMHWDZljCkePZScSKtBF6FcVUDhqZaKB2mD7FhbFffFc2ig17gpwzZFOxyPsiYb7sF0Z5azscwREO3CaDw0lX1OlcUdIU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785582071; c=relaxed/simple; bh=eH7MOUuGodxq09rRikBFhUdpvaOczF07qkwIpXsPdnM=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=bJv4LWnduxfzEyPFK6iujCAXFmBl4gGBs/P3D/AcPqdNRvo/MQ/SClwo96OQDkAvDKKVmTXjPPVFPusG0bvOOWPs5FeZCpPOEb+lkhB8DvSRtXTaUcdFvy5DR1xQFfCm2pE4xkAACh5C78l8SsSIILWMTFaW2gckyRq541DIWgI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=mavick.dev; spf=pass smtp.mailfrom=mavick.dev; dkim=pass (2048-bit key) header.d=mavick.dev header.i=@mavick.dev header.b=xQS5CzkI; arc=none smtp.client-ip=80.241.56.171 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=mavick.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mavick.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=mavick.dev header.i=@mavick.dev header.b="xQS5CzkI" Received: from smtp1.mailbox.org (smtp1.mailbox.org [IPv6:2001:67c:2050:b231:465::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mout-p-201.mailbox.org (Postfix) with ESMTPS id 4hC0Nf70nBzMlGF; Sat, 01 Aug 2026 13:01:06 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mavick.dev; s=MBO0001; t=1785582067; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=jTMRjFLThSMMc/w3StUWqu1LpTWLAsUOncWy0PHshAk=; b=xQS5CzkIcPO109Cb+436Qqh/cxYj3inN1re6Kjq5Boj4l3I1jsOvvNNKHFxwTEa+mnx5YT x8s+MjZu0OWymu98RI9/82lzQcCq+5xcpxjoM2ziXjyF6FhkJm3vslJ/Mr9rBm1jxMMFPU HNfDwHkPmKwNzJbuXSzQeUPfgKjbDHpJwAQjzOPGqB125yBnQ8tJzMcSotAA5FcPRnveHW OiUDYFDo4YJIFn8+mfHqQu+E79pWcbroR1NktHv5qvX+TePUiUdc+DeZRB4PB+1v0Uycg6 gp3BlzM4yye6JXSBRrlw7mUXCkB4wqZLmBCPZQBorRKi0smgiPiRAjT310k3xA== Authentication-Results: outgoing_mbo_mout; dkim=none; spf=pass (outgoing_mbo_mout: domain of m@mavick.dev designates 2001:67c:2050:b231:465::1 as permitted sender) smtp.mailfrom=m@mavick.dev From: Eugene Mavick Date: Sat, 01 Aug 2026 18:59:44 +0800 Subject: [PATCH v4 4/5] kunit: add test for ref_trace_final_put Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260801-refcount-final-put-trace-v4-4-2e58678f0ffd@mavick.dev> References: <20260801-refcount-final-put-trace-v4-0-2e58678f0ffd@mavick.dev> In-Reply-To: <20260801-refcount-final-put-trace-v4-0-2e58678f0ffd@mavick.dev> To: Will Deacon , Peter Zijlstra , Boqun Feng , Mark Rutland , Gary Guo , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Andrew Morton , Dennis Zhou , Tejun Heo , Christoph Lameter Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-mm@kvack.org, Eugene Mavick X-Developer-Signature: v=1; a=openpgp-sha256; l=5222; i=m@mavick.dev; h=from:subject:message-id; bh=eH7MOUuGodxq09rRikBFhUdpvaOczF07qkwIpXsPdnM=; b=owGbwMvMwCU2V/5U3e1aE3/G02pJDFm5Fzd2a7LeeL66USZ99ZaZBwMjjzFOvK/B4bGnofX9+ Wb+hIspHaUsDGJcDLJiiiw1WQnuGStnJRofndQDM4eVCWQIAxenAExk7TSG36yLF5nvyLvHoHNv nZQ0wzRDhdyY6Ih0u79mvhcnaO340cvwv1TgpVYAuwuPSIqFlf4WA7GDt81l+iRYLmrNPH3VJPo bHwA= X-Developer-Key: i=m@mavick.dev; a=openpgp; fpr=7C6A604768A99A6133C5928C9D1FCA7EDB7D344F X-Rspamd-Queue-Id: 4hC0Nf70nBzMlGF Add a KUnit test suite for the ref_trace_final_put tracepoint. The test registers a probe function and triggers both refcount_t and percpu_ref final put paths, verifying that the tracepoint fires correctly and that the recorded fields match expected values. Signed-off-by: Eugene Mavick --- lib/Kconfig | 10 ++++ lib/tests/Makefile | 1 + lib/tests/ref_trace_kunit.c | 141 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 152 insertions(+) diff --git a/lib/Kconfig b/lib/Kconfig index 00a9509636c1..7e2746be6d16 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -52,6 +52,16 @@ config PACKING_KUNIT_TEST When in doubt, say N. +config REF_TRACE_KUNIT_TEST + bool "ref_trace kunit test" if !KUNIT_ALL_TESTS + depends on KUNIT && TRACEPOINTS + default KUNIT_ALL_TESTS + help + This option enables the KUnit test suite for the ref_trace_final_put + tracepoint. + + If unsure, say N. + config BITREVERSE tristate diff --git a/lib/tests/Makefile b/lib/tests/Makefile index 7e9c2fa52e35..828a030ad8c7 100644 --- a/lib/tests/Makefile +++ b/lib/tests/Makefile @@ -57,5 +57,6 @@ obj-$(CONFIG_USERCOPY_KUNIT_TEST) += usercopy_kunit.o obj-$(CONFIG_UTIL_MACROS_KUNIT) += util_macros_kunit.o obj-$(CONFIG_RATELIMIT_KUNIT_TEST) += test_ratelimit.o obj-$(CONFIG_UUID_KUNIT_TEST) += uuid_kunit.o +obj-$(CONFIG_REF_TRACE_KUNIT_TEST) += ref_trace_kunit.o obj-$(CONFIG_TEST_RUNTIME_MODULE) += module/ diff --git a/lib/tests/ref_trace_kunit.c b/lib/tests/ref_trace_kunit.c new file mode 100644 index 000000000000..17f6936ecc1a --- /dev/null +++ b/lib/tests/ref_trace_kunit.c @@ -0,0 +1,141 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct data { + unsigned long caller; + unsigned long ip; + const void *obj; + atomic_t count; +}; + +struct data capture; + +const void *chk_obj; + +#define test_init() \ + do { \ + KUNIT_EXPECT_FALSE( \ + test, register_trace_ref_trace_final_put(probe, NULL)); \ + \ + atomic_set_release(&capture.count, 0); \ + \ + chk_obj = &obj; \ + } while (0) + + +#define test_exit() \ + do { \ + /* wait for probe completion */ \ + int notimeout = wait_var_event_timeout( \ + &capture.count, \ + atomic_read_acquire(&capture.count), \ + msecs_to_jiffies(10000) \ + ); \ + \ + unregister_trace_ref_trace_final_put(probe, NULL); \ + tracepoint_synchronize_unregister(); \ + \ + KUNIT_ASSERT_TRUE(test, notimeout); \ + \ + KUNIT_EXPECT_EQ(test, atomic_read_acquire(&capture.count), 1); \ + \ + KUNIT_EXPECT_TRUE(test, __kernel_text_address(capture.caller)); \ + KUNIT_EXPECT_TRUE(test, __kernel_text_address(capture.ip)); \ + \ + KUNIT_EXPECT_PTR_EQ(test, capture.obj, &obj); \ + } while (0) + +static void probe( + void *ignore, + unsigned long caller, + unsigned long ip, + const void *obj) +{ + //prevent non test func final_puts from changing captured values + if (chk_obj != obj) + return; + + capture.caller = caller; + capture.ip = ip; + capture.obj = obj; + + atomic_inc_return_release(&capture.count); //increase count +} + +static void test_refcount_sub_and_test(struct kunit *test) +{ + refcount_t obj; + + test_init(); + refcount_set(&obj, 2); + + KUNIT_EXPECT_FALSE(test, refcount_dec_and_test(&obj)); + KUNIT_EXPECT_TRUE(test, refcount_dec_and_test(&obj)); + + test_exit(); +} + +static void test_refcount_dec_if_one(struct kunit *test) +{ + refcount_t obj; + + test_init(); + refcount_set(&obj, 2); + + KUNIT_EXPECT_FALSE(test, refcount_dec_and_test(&obj)); + KUNIT_EXPECT_TRUE(test, refcount_dec_if_one(&obj)); + + test_exit(); +} +static void dummy_release(struct percpu_ref *ref) {} + +static void test_percpu_ref_put_many(struct kunit *test) +{ + struct percpu_ref obj; + + test_init(); + + KUNIT_ASSERT_FALSE(test, percpu_ref_init(&obj, dummy_release, 0, GFP_KERNEL)); + + percpu_ref_get(&obj); + percpu_ref_get(&obj); + + percpu_ref_put(&obj); + percpu_ref_put(&obj); + + percpu_ref_switch_to_atomic_sync(&obj); + + percpu_ref_put(&obj); + + test_exit(); + percpu_ref_exit(&obj); +} + +static struct kunit_case __refdata ref_trace_test_cases[] = { + KUNIT_CASE(test_refcount_sub_and_test), + KUNIT_CASE(test_refcount_dec_if_one), + KUNIT_CASE(test_percpu_ref_put_many), + {} +}; + +static struct kunit_suite ref_trace_test_suite = { + .name = "ref-trace", + .test_cases = ref_trace_test_cases +}; + +kunit_test_suites(&ref_trace_test_suite); + +MODULE_AUTHOR("Eugene Mavick "); +MODULE_DESCRIPTION("KUnit test for ref_trace"); +MODULE_LICENSE("GPL"); -- 2.51.2