From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta1.migadu.com (out-1.mta1.migadu.com [95.215.58.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4279944607C for ; Wed, 26 Aug 2026 14:57:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.1 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787756235; cv=none; b=jlScYew/4zrzhIeSbwBU8jhe31zc4Iimi+0LvKg40JL/V8awoHPfgFLuS1zq+vuxUqKztRDrwOWezbZHwtgYygyuP1dbo8BEUCI0wpWp1WzBDIMlobaEyLXsX+WLe+08F7LSZmoPnCwTewXNQ0PDrXH7pW8mgz5dfDfzDqoDpDY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787756235; c=relaxed/simple; bh=P61/CZ4aaAwA+5xlFDVZ1Xvshkk76UHu0j9/A+GJqM4=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=ax/DqB0HVRBjv9DHCJSDYODp2wnr94HpU2ogAgYkcqOw4d3eEZTHL+VuPGRGlcjUePvD3CFmKy+koLYqytSmB669heCwdzQBtiQcWwod1knAbcddokLKPWRwd8nZbBL6M+loRJCXtqzGhA6oPBh4IMHcEOWmBb+Ls4w1uKcDKQA= 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=Rzf9IDFw; arc=none smtp.client-ip=95.215.58.1 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="Rzf9IDFw" X-Envelope-To: bpf@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=P61/CZ4aaAwA+5xlFDVZ1Xvshkk76UHu0j9/A+GJqM4=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1787756230; v=1; x=1788361030; b=Rzf9IDFwMKl6KzknVjsVfIR6cmuh2fPklErq+Hc8B+eNsk9LwNRtb394htFmWHrwqveLznPp K/zKFqRTRw2yiwF62iqEUe8PtjbxJsQIUvktouNxbVxDrkba0LAEbhQmismHjN1or6odpw36Hts Z3YpR4FpyF1q3rATP+1sQORQ= X-Envelope-To: bpf@vger.kernel.org Received: from .linux.dev (117.20.148.1) by smtp.migadu.com with ESMTPS id 99426f2ea7423afc; Wed, 26 Aug 2026 14:57:09 +0000 X-Mizu-Trace-ID: 99426f2ea7423afc X-Migadu-Flow: FLOW_OUT From: Leon Hwang To: bpf@vger.kernel.org Cc: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Eduard Zingerman , Kumar Kartikeya Dwivedi , Martin KaFai Lau , Song Liu , Yonghong Song , Jiri Olsa , Emil Tsalapatis , Ihor Solodrai , Shuah Khan , Leon Hwang , linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH bpf-next v3] selftests/bpf: Avoid flaky resize value test for percpu data Date: Wed, 26 Aug 2026 22:56:13 +0800 Message-ID: <20260826145613.34182-1-leon.hwang@linux.dev> X-Mailer: git-send-email 2.55.0 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The bpf_map__set_value_size() test for percpu data relies on the tail 'cpu_id' field in the ".percpu" map. The test would fail, when 'cpu_id' is not the last field in the map. To avoid the flaky test, factor out a subtest to use a dedicated ".percpu.arr" map that only has one field 'int arr[1]'. And, skip the subtest when fail to load skel with errno E2BIG and the new value size is larger than ALIGN(32KiB, PAGE_SIZE). And, drop 'args' in test_percpu_data_on_cpus(), which isn't used in bpf prog side. And, enhance the test to cover 'set' and 'nums[6]'. Fixes: 4c9241bd731a ("selftests/bpf: Add tests to verify global percpu data") Signed-off-by: Leon Hwang --- v2 -> v3: * Drop 4KiB page size guard. (Andrii) * Expect -E2BIG, and skip the test, when PAGE_SIZE is >= 64KiB. (Andrii) * v2: https://lore.kernel.org/bpf/20260818153202.90714-1-leon.hwang@linux.dev/ v1 -> v2: * Factor out a subtest to test bpf_map__set_value_size(). * Run the new subtest only on 4K page systems. (Sashiko) * v1: https://lore.kernel.org/bpf/20260814173206.93082-5-leon.hwang@linux.dev/ --- .../bpf/prog_tests/global_data_init.c | 96 ++++++++++++++----- .../bpf/progs/test_global_percpu_data.c | 10 +- 2 files changed, 80 insertions(+), 26 deletions(-) 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 5671c31085cd..7c539cbcf3a1 100644 --- a/tools/testing/selftests/bpf/prog_tests/global_data_init.c +++ b/tools/testing/selftests/bpf/prog_tests/global_data_init.c @@ -68,12 +68,9 @@ static void test_percpu_data_on_cpus(struct bpf_map *map, int map_fd, int prog_f { struct test_global_percpu_data__percpu *data = NULL; int i, err, key = 0, num_online, run = 0; - __u64 args[2] = {0x1234ULL, 0x5678ULL}; size_t data_sz; bool *online; LIBBPF_OPTS(bpf_test_run_opts, topts, - .ctx_in = args, - .ctx_size_in = sizeof(args), .flags = BPF_F_TEST_RUN_ON_CPU, ); @@ -81,7 +78,7 @@ static void test_percpu_data_on_cpus(struct bpf_map *map, int map_fd, int prog_f if (!ASSERT_OK(err, "parse_cpu_mask_file")) return; - data_sz = map ? bpf_map__value_size(map) : sizeof(*data); + data_sz = sizeof(*data); data = calloc(1, data_sz); if (!ASSERT_OK_PTR(data, "calloc percpu data")) goto out; @@ -109,7 +106,7 @@ static void test_percpu_data_on_cpus(struct bpf_map *map, int map_fd, int prog_f break; ASSERT_EQ(*runp, ++run, "run"); - ASSERT_EQ(data->cpu_id[0], i, "cpu_id"); + ASSERT_EQ(data->cpu_id, i, "cpu_id"); ASSERT_EQ(data->data, 1, "data"); ASSERT_TRUE(data->set, "set"); ASSERT_EQ(data->nums[6], 0xc0de, "nums[6]"); @@ -127,7 +124,6 @@ static void test_global_percpu_data_init(void) { struct test_global_percpu_data__percpu init_value = {}; struct test_global_percpu_data__percpu *init_data; - const __u32 desired_sz = sysconf(_SC_PAGE_SIZE); struct test_global_percpu_data *skel = NULL; size_t init_data_sz; struct bpf_map *map; @@ -163,9 +159,11 @@ static void test_global_percpu_data_init(void) if (!ASSERT_EQ(bpf_map__type(map), BPF_MAP_TYPE_PERCPU_ARRAY, "bpf_map__type")) goto out; + init_value.set = 1; init_value.data = 2; init_value.nums[6] = -1; init_value.struct_data.i = 2; + init_value.struct_data.set = 1; init_value.struct_data.nums[6] = -1; err = bpf_map__set_initial_value(map, &init_value, sizeof(init_value)); if (!ASSERT_OK(err, "bpf_map__set_initial_value")) @@ -177,35 +175,24 @@ static void test_global_percpu_data_init(void) ASSERT_EQ(init_data->data, init_value.data, "init_value data"); ASSERT_EQ(init_data->set, init_value.set, "init_value set"); + ASSERT_EQ(init_data->nums[6], init_value.nums[6], "init_value nums[6]"); ASSERT_EQ(init_data->struct_data.i, init_value.struct_data.i, "init_value struct_data.i"); + ASSERT_EQ(init_data->struct_data.set, init_value.struct_data.set, + "init_value struct_data.set"); ASSERT_EQ(init_data->struct_data.nums[6], init_value.struct_data.nums[6], "init_value struct_data.nums[6]"); ASSERT_EQ(init_data_sz, sizeof(init_value), "init_value size"); ASSERT_EQ((void *) init_data, (void *) skel->percpu, "skel->percpu eq init_data"); ASSERT_EQ(skel->percpu->data, init_value.data, "skel->percpu->data"); ASSERT_EQ(skel->percpu->set, init_value.set, "skel->percpu->set"); + ASSERT_EQ(skel->percpu->nums[6], init_value.nums[6], "skel->percpu->nums[6]"); ASSERT_EQ(skel->percpu->struct_data.i, init_value.struct_data.i, "skel->percpu->struct_data.i"); + ASSERT_EQ(skel->percpu->struct_data.set, init_value.struct_data.set, + "skel->percpu->struct_data.set"); ASSERT_EQ(skel->percpu->struct_data.nums[6], init_value.struct_data.nums[6], "skel->percpu->struct_data.nums[6]"); - ASSERT_GT(desired_sz, sizeof(init_value), "desired_sz"); - err = bpf_map__set_value_size(map, desired_sz); - if (!ASSERT_OK(err, "bpf_map__set_value_size")) - goto out; - if (!ASSERT_EQ(bpf_map__value_size(map), desired_sz, "percpu value size")) - goto out; - if (!ASSERT_NEQ(bpf_map__btf_value_type_id(map), 0, "percpu BTF value type")) - goto out; - - init_data = bpf_map__initial_value(map, &init_data_sz); - if (!ASSERT_OK_PTR(init_data, "resized bpf_map__initial_value")) - goto out; - if (!ASSERT_EQ(init_data_sz, desired_sz, "resized initial value size")) - goto out; - if (!ASSERT_EQ(init_data->data, init_value.data, "resized initial value data")) - goto out; - err = test_global_percpu_data__load(skel); if (!ASSERT_OK(err, "test_global_percpu_data__load")) goto out; @@ -236,6 +223,67 @@ static void test_global_percpu_data_lskel(void) test_global_percpu_data_lskel__destroy(lskel); } +#define PCPU_MIN_UNIT_SIZE (32 << 10) + +static void test_global_percpu_data_map_resize(void) +{ + const __u32 page_size = sysconf(_SC_PAGE_SIZE); + const __u32 pcpu_max_value_size = ALIGN(PCPU_MIN_UNIT_SIZE, page_size); + const __u32 desired_sz = page_size * 2; + struct test_global_percpu_data *skel; + const int arr_value = -1; + struct bpf_map *map; + int err, prog_fd; + size_t data_sz; + + skel = test_global_percpu_data__open(); + if (!ASSERT_OK_PTR(skel, "test_global_percpu_data__open")) + return; + + map = skel->maps.percpu_arr; + skel->percpu_arr->arr[0] = arr_value; + err = bpf_map__set_value_size(map, desired_sz); + if (!ASSERT_OK(err, "bpf_map__set_value_size")) + goto out; + if (!ASSERT_EQ(bpf_map__value_size(map), desired_sz, "bpf_map__value_size")) + goto out; + if (!ASSERT_NEQ(bpf_map__btf_value_type_id(map), 0, "bpf_map__btf_value_type_id")) + goto out; + + skel->percpu_arr = bpf_map__initial_value(map, &data_sz); + if (!ASSERT_EQ(data_sz, desired_sz, "data_sz")) + goto out; + if (!ASSERT_OK_PTR(skel->percpu_arr, "skel->percpu_arr")) + goto out; + if (!ASSERT_EQ(skel->percpu_arr->arr[0], arr_value, "arr[0]")) + goto out; + + err = test_global_percpu_data__load(skel); + if (bpf_map__value_size(map) > pcpu_max_value_size) { + if (ASSERT_EQ(err, -E2BIG, "test_global_percpu_data__load E2BIG")) + /* + * When the PAGE_SIZE is 64KiB, the new value size will + * be 128KiB. Creating a percpu_array map with the new + * value size will fail with -E2BIG due to percpu_array + * map value size limit 64KiB, which is calculated by + * PFN_ALIGN(32KiB). + * Let's skip the test for such case. + */ + test__skip(); + goto out; + } + if (!ASSERT_OK(err, "test_global_percpu_data__load")) + goto out; + + map = skel->maps.percpu; + prog_fd = bpf_program__fd(skel->progs.update_percpu_data); + test_percpu_data_on_cpus(map, bpf_map__fd(map), prog_fd, &skel->bss->run); + ASSERT_EQ(skel->bss->arr_sum, arr_value * skel->bss->run, "arr_sum"); + +out: + test_global_percpu_data__destroy(skel); +} + static int create_rdonly_percpu_array(void) { LIBBPF_OPTS(bpf_map_create_opts, map_opts, @@ -388,6 +436,8 @@ void test_global_percpu_data(void) test_global_percpu_data_init(); if (test__start_subtest("lskel")) test_global_percpu_data_lskel(); + if (test__start_subtest("map_resize")) + test_global_percpu_data_map_resize(); if (test__start_subtest("rdonly_direct_read")) test_global_percpu_data_rdonly_direct_read(); if (test__start_subtest("rdonly_direct_write")) 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 5dc21b3b4cb5..2765cd46e9af 100644 --- a/tools/testing/selftests/bpf/progs/test_global_percpu_data.c +++ b/tools/testing/selftests/bpf/progs/test_global_percpu_data.c @@ -8,9 +8,12 @@ int loong SEC(".percpu.looooooooong"); int data3 SEC(".data.percpu"); int data2 SEC(".percpu.data"); +/* Used for testing bpf_map__set_value_size(). */ +int arr[1] SEC(".percpu.arr"); +int arr_sum; + int run; -/* cpu_id as array to verify map value resizing. */ -int cpu_id[1] SEC(".percpu"); +int cpu_id SEC(".percpu"); int data SEC(".percpu") = -1; int nums[7] SEC(".percpu"); bool set SEC(".percpu") = false; @@ -34,7 +37,8 @@ int update_percpu_data(void *ctx) data = 1; run++; set = true; - cpu_id[0] = bpf_get_smp_processor_id(); + cpu_id = bpf_get_smp_processor_id(); + arr_sum += arr[0]; return 0; } -- 2.55.0