From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-181.mta1.migadu.com (out-181.mta1.migadu.com [95.215.58.181]) (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 7817F3E6DDA for ; Tue, 14 Apr 2026 13:26:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.181 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776173163; cv=none; b=JlLEpnE32nfXrOUZDSUp3yVJuQ6pXFyM0DlyPqwF9uDD0pjoPOfIydg0vRhv0S71ZNVZyJm1OPczlOiv36BHlSlei2YKLRWe2595jqaZRXilR9hTwI5jgKWKRHP8l4uhwScwkWIVTmkQq6LOCdHodXGqmVoUoCscvM3rKQn4dV4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776173163; c=relaxed/simple; bh=zSQdD2Q0MsdiSayYIbFrHXBJOq4ODP5pBF6xVJ9Z+rY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=KeZcH9xHvrQDxtrhKTThZup1tvKcb7TjCOVtfJ9BmoTQOw3/gfVVDe67RnQowoXXwiP+WkD43C9TPvIeQ73RGBNqtvZiqnpdi027ziupw7AvWLwV2BVok9rnbdHNmwFBa6USeIg7xcYo2MekM0+Sy5jweP4CQZAjOtEl4Gwoy00= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=QkGhQ7Ov; arc=none smtp.client-ip=95.215.58.181 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="QkGhQ7Ov" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1776173160; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=SLsBEILRFj2uxpy0K8iic1oVr+hSITfXzsUFYSG7iJk=; b=QkGhQ7Ovf1X3ZPSHr91p0lFuorOSL4dJtDHvSdPLMxTHCYpvuCkPlAc+hegAa7HQY6Y3OR vuSz/+gAJTy5QWsZbONAteFjfzy+bVKPD9KuB705zRjOqzjIl0tye91ULw7Otrmb+gjiof gW4azHU87z23lc2uywnpBMHXIdf6vyQ= From: Leon Hwang To: bpf@vger.kernel.org Cc: ast@kernel.org, andrii@kernel.org, daniel@iogearbox.net, yonghong.song@linux.dev, song@kernel.org, eddyz87@gmail.com, qmo@kernel.org, dxu@dxuuu.xyz, leon.hwang@linux.dev, kernel-patches-bot@fb.com Subject: [PATCH bpf-next v4 8/8] selftests/bpf: Add a test to verify bpf_iter for global percpu data Date: Tue, 14 Apr 2026 21:24:20 +0800 Message-ID: <20260414132421.63409-9-leon.hwang@linux.dev> In-Reply-To: <20260414132421.63409-1-leon.hwang@linux.dev> References: <20260414132421.63409-1-leon.hwang@linux.dev> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT Add a test to verify that it is OK to iter the percpu_array map used for global percpu data. Signed-off-by: Leon Hwang --- .../bpf/prog_tests/global_data_init.c | 53 +++++++++++++++++++ .../bpf/progs/test_global_percpu_data.c | 36 +++++++++++++ 2 files changed, 89 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/global_data_init.c b/tools/testing/selftests/bpf/prog_tests/global_data_init.c index 0b0384b6515e..9ff09ff1981c 100644 --- a/tools/testing/selftests/bpf/prog_tests/global_data_init.c +++ b/tools/testing/selftests/bpf/prog_tests/global_data_init.c @@ -269,6 +269,57 @@ static void test_global_percpu_data_verifier_failure(void) RUN_TESTS(test_global_percpu_data); } +static void test_global_percpu_data_iter(void) +{ + DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts); + struct test_global_percpu_data *skel; + union bpf_iter_link_info linfo = {}; + struct bpf_link *link = NULL; + int fd, num_cpus, len, err; + char buf[16]; + + num_cpus = libbpf_num_possible_cpus(); + if (!ASSERT_GT(num_cpus, 0, "libbpf_num_possible_cpus")) + return; + + skel = test_global_percpu_data__open(); + if (!ASSERT_OK_PTR(skel, "test_global_percpu_data__open")) + return; + + skel->rodata->num_cpus = num_cpus; + skel->percpu->struct_data.nums[6] = 0xc0de; + + err = test_global_percpu_data__load(skel); + if (err == -EOPNOTSUPP) { + test__skip(); + goto out; + } + if (!ASSERT_OK(err, "test_global_percpu_data__load")) + goto out; + + linfo.map.map_fd = bpf_map__fd(skel->maps.percpu); + opts.link_info = &linfo; + opts.link_info_len = sizeof(linfo); + link = bpf_program__attach_iter(skel->progs.dump_percpu_data, &opts); + if (!ASSERT_OK_PTR(link, "bpf_program__attach_iter")) + goto out; + + fd = bpf_iter_create(bpf_link__fd(link)); + if (!ASSERT_GE(fd, 0, "bpf_iter_create")) + goto out; + + while ((len = read(fd, buf, sizeof(buf))) > 0) + do { } while (0); + ASSERT_EQ(len, 0, "read iter"); + ASSERT_TRUE(skel->bss->run_iter, "run_iter"); + ASSERT_EQ(skel->bss->percpu_data_sum, 0xc0de * num_cpus, "percpu_data_sum"); + + close(fd); +out: + bpf_link__destroy(link); + test_global_percpu_data__destroy(skel); +} + void test_global_percpu_data(void) { if (!feat_supported(NULL, FEAT_PERCPU_DATA)) { @@ -282,4 +333,6 @@ void test_global_percpu_data(void) test_global_percpu_data_lskel(); if (test__start_subtest("verifier_failure")) test_global_percpu_data_verifier_failure(); + if (test__start_subtest("iter")) + test_global_percpu_data_iter(); } diff --git a/tools/testing/selftests/bpf/progs/test_global_percpu_data.c b/tools/testing/selftests/bpf/progs/test_global_percpu_data.c index 947721c21f30..0ddb820509eb 100644 --- a/tools/testing/selftests/bpf/progs/test_global_percpu_data.c +++ b/tools/testing/selftests/bpf/progs/test_global_percpu_data.c @@ -63,4 +63,40 @@ int verifier_percpu_read(void *ctx) return c == 'd'; } +volatile const __u32 num_cpus = 0; +__u32 percpu_data_sum = 0; +bool run_iter = false; + +SEC("iter/bpf_map_elem") +__auxiliary +int dump_percpu_data(struct bpf_iter__bpf_map_elem *ctx) +{ + struct { + int data; + char run; + struct { + char set; + int i; + int nums[7]; + } struct_data; + int nums[7]; + } *pptr = ctx->value; + __u32 step; + int i; + + if (!pptr) + return 0; + + run_iter = true; + + /* percpu array element size is aligned to 8 */ + step = (sizeof(*pptr) + 7) & ~7; + + for (i = 0; i < num_cpus; i++) { + percpu_data_sum += pptr->struct_data.nums[6]; + pptr = (void *)pptr + step; + } + return 0; +} + char _license[] SEC("license") = "GPL"; -- 2.53.0