From patchwork Fri Jun 13 05:17:30 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 897218 Received: from NAM11-DM6-obe.outbound.protection.outlook.com (mail-dm6nam11on2088.outbound.protection.outlook.com [40.107.223.88]) (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 7C93D25BEE3; Fri, 13 Jun 2025 05:18:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.107.223.88 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749791904; cv=fail; b=TzaDbbNroT1TBy5vCriEW87V4JXgu7TjHfgSdlQc2wWJf/unjPRcSgQz+siSD/IzSfHCmpYLBDjgODHmBt4/mRWzCVrYGtDR3i6+8bdZznC1Z0N9swxn4EwpYtpcOqmzbXVJF5jdplTlA/xNPkeUzBLYGanVT+eykk736ajTe7Q= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749791904; c=relaxed/simple; bh=exkumhOdiw8oCUesu0VJD1IP/BQ70lXXxX8BzKUffWw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: Content-Type:MIME-Version; b=jkCfJxElc91BteZVnkZHjPQMhrJs2hwZq6mfhUU7Yz/aXyCCwE13aXx7jD43YUtZslCFWqR0LECMuFj2wIv40IiY3PobEpuJnEdcjFjlvYotVMNIpnanbDEwtLRcoPl/VMkBQ4xWbEvAY8kBcmTYiXBpnu6uTgja7A34ESLvGyQ= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com; spf=fail smtp.mailfrom=nvidia.com; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b=NznxSKKQ; arc=fail smtp.client-ip=40.107.223.88 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=nvidia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b="NznxSKKQ" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=asAQinyi4PufG/Wkx8ecOCKueVIrNY7gN9v1oolbE96XYAqJlJTrjyzC8DPYQh6LSJwa5XWEb4cL4dFKCemakbsncU4mQxDQvRNGyMEMfW9Zdv5r5JWR+LaonzxSGOGM4Q+jZZM1TfmaadNeCy1k40HLN1vlaJ6wUefoGZLq2A9NoATuOBuos9/VKLE+6aa+9DuTStkuUrZEdmHRmLqc69Q5kq/16J3Fo8jfHvvwO09xHtmTnpt9ZcuJKJcUyItyYSxt3RNLRyOTFiMGX/puDsLZzcbjP90yJm7o7kxWK3fgldGcjeWqBNQCOqj+xN/8tQCESzZdqLomoujED1IHkQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=wWQDALDMbn5MR/+nWBcS7NuCJZiB121+OKagfgAC3C4=; b=EMsOi4nhTebCkLNxjyx0dvJHOhPOSJW26ZalXSutrQickuRid+8ZoGTYn/06R3pPFemiSjH+OspK0X1AtRSktgzsXKOhv/mA2c1YcwoCs97szio6cZbb3tZodlXkEXw1PnlNhiAVHwBH1THzYWpQo4bgqM6kRvErsSFi4zwyDIPv4ctif55KBT9GzqlvMcNhhvmYfEOBGq/CSwZv681qCFTfb6Gp89Hgciq2KGZhnZXzyymQktD2YOg2T3PDIuiQNnKqsnnIpCqCjZA/Y4gdGiFSCTw8z9aYlZwwyJqMVIiNqADlgBld8Grx34pwfJ48DJFDJy3kVvTScE5if7cukg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=wWQDALDMbn5MR/+nWBcS7NuCJZiB121+OKagfgAC3C4=; b=NznxSKKQdTRF0o08RVQW9sZsr/2bWF7w6Z/wWyOdWY6UX0YUGOFmeTD7BTQdxv0JCWS9nDFBafrHnlN/zv4+ZtNPuA3Wd9URRgt8jlyYjlpvP3FKF49UWjNTl3GFZuVey5N8AB/7AmmdpmI62VcAh/J2lJYSqvpTYN5fOpzKOPU0iPnEb6wY7zgwxB449qeIW4ajttfv7qzY+Bjq14nLYUt2l7wxQ81aKrLkXoWVHLApGLJK0Moc7HAx6XgEEQdEruKUE5spKqdIhcRFO8OR7awMkaTcf5DUuopIh4Bl3GNmvzG0wOGquC72VNTquNcPo+wZGuO/Xa04CHrJWyT1ZA== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from SN7PR12MB8059.namprd12.prod.outlook.com (2603:10b6:806:32b::7) by DM4PR12MB9071.namprd12.prod.outlook.com (2603:10b6:8:bd::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8835.19; Fri, 13 Jun 2025 05:18:17 +0000 Received: from SN7PR12MB8059.namprd12.prod.outlook.com ([fe80::4ee2:654e:1fe8:4b91]) by SN7PR12MB8059.namprd12.prod.outlook.com ([fe80::4ee2:654e:1fe8:4b91%3]) with mapi id 15.20.8792.034; Fri, 13 Jun 2025 05:18:17 +0000 From: Joel Fernandes To: linux-kernel@vger.kernel.org, Tejun Heo , David Vernet , Andrea Righi , Changwoo Min , Shuah Khan Cc: Joel Fernandes , Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , linux-kselftest@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH v3 10/10] selftests/sched_ext: Add test for sched_ext dl_server Date: Fri, 13 Jun 2025 01:17:30 -0400 Message-ID: <20250613051734.4023260-11-joelagnelf@nvidia.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250613051734.4023260-1-joelagnelf@nvidia.com> References: <20250613051734.4023260-1-joelagnelf@nvidia.com> X-ClientProxiedBy: BL0PR02CA0017.namprd02.prod.outlook.com (2603:10b6:207:3c::30) To SN7PR12MB8059.namprd12.prod.outlook.com (2603:10b6:806:32b::7) Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SN7PR12MB8059:EE_|DM4PR12MB9071:EE_ X-MS-Office365-Filtering-Correlation-Id: 5b29f82d-4c67-4b4b-302d-08ddaa39b3e0 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|7416014|376014|1800799024; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:SN7PR12MB8059.namprd12.prod.outlook.com; PTR:; CAT:NONE; SFS:(13230040)(366016)(7416014)(376014)(1800799024); DIR:OUT; SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: 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 X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 5b29f82d-4c67-4b4b-302d-08ddaa39b3e0 X-MS-Exchange-CrossTenant-AuthSource: SN7PR12MB8059.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Jun 2025 05:18:16.5584 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: wRq+UDYv6s4bjHs3bAjGBXVudF9De6X5aX1k43Ad+I1Ua3MhuZxLoHHUYLh3qjoMAEqzFAYOuUFjrOTsltCp+Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB9071 From: Andrea Righi Add a selftest to validate the correct behavior of the deadline server for the ext_sched_class. [ Joel: Replaced occurences of CFS in the test with EXT. ] Signed-off-by: Joel Fernandes Signed-off-by: Andrea Righi --- tools/testing/selftests/sched_ext/Makefile | 1 + .../selftests/sched_ext/rt_stall.bpf.c | 23 ++ tools/testing/selftests/sched_ext/rt_stall.c | 213 ++++++++++++++++++ 3 files changed, 237 insertions(+) create mode 100644 tools/testing/selftests/sched_ext/rt_stall.bpf.c create mode 100644 tools/testing/selftests/sched_ext/rt_stall.c diff --git a/tools/testing/selftests/sched_ext/Makefile b/tools/testing/selftests/sched_ext/Makefile index f4531327b8e7..dcc803eeab39 100644 --- a/tools/testing/selftests/sched_ext/Makefile +++ b/tools/testing/selftests/sched_ext/Makefile @@ -181,6 +181,7 @@ auto-test-targets := \ select_cpu_dispatch_bad_dsq \ select_cpu_dispatch_dbl_dsp \ select_cpu_vtime \ + rt_stall \ test_example \ testcase-targets := $(addsuffix .o,$(addprefix $(SCXOBJ_DIR)/,$(auto-test-targets))) diff --git a/tools/testing/selftests/sched_ext/rt_stall.bpf.c b/tools/testing/selftests/sched_ext/rt_stall.bpf.c new file mode 100644 index 000000000000..80086779dd1e --- /dev/null +++ b/tools/testing/selftests/sched_ext/rt_stall.bpf.c @@ -0,0 +1,23 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * A scheduler that verified if RT tasks can stall SCHED_EXT tasks. + * + * Copyright (c) 2025 NVIDIA Corporation. + */ + +#include + +char _license[] SEC("license") = "GPL"; + +UEI_DEFINE(uei); + +void BPF_STRUCT_OPS(rt_stall_exit, struct scx_exit_info *ei) +{ + UEI_RECORD(uei, ei); +} + +SEC(".struct_ops.link") +struct sched_ext_ops rt_stall_ops = { + .exit = (void *)rt_stall_exit, + .name = "rt_stall", +}; diff --git a/tools/testing/selftests/sched_ext/rt_stall.c b/tools/testing/selftests/sched_ext/rt_stall.c new file mode 100644 index 000000000000..d4cb545ebfd8 --- /dev/null +++ b/tools/testing/selftests/sched_ext/rt_stall.c @@ -0,0 +1,213 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2025 NVIDIA Corporation. + */ +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "rt_stall.bpf.skel.h" +#include "scx_test.h" +#include "../kselftest.h" + +#define CORE_ID 0 /* CPU to pin tasks to */ +#define RUN_TIME 5 /* How long to run the test in seconds */ + +/* Simple busy-wait function for test tasks */ +static void process_func(void) +{ + while (1) { + /* Busy wait */ + for (volatile unsigned long i = 0; i < 10000000UL; i++); + } +} + +/* Set CPU affinity to a specific core */ +static void set_affinity(int cpu) +{ + cpu_set_t mask; + + CPU_ZERO(&mask); + CPU_SET(cpu, &mask); + if (sched_setaffinity(0, sizeof(mask), &mask) != 0) { + perror("sched_setaffinity"); + exit(EXIT_FAILURE); + } +} + +/* Set task scheduling policy and priority */ +static void set_sched(int policy, int priority) +{ + struct sched_param param; + + param.sched_priority = priority; + if (sched_setscheduler(0, policy, ¶m) != 0) { + perror("sched_setscheduler"); + exit(EXIT_FAILURE); + } +} + +/* Get process runtime from /proc//stat */ +static float get_process_runtime(int pid) +{ + char path[256]; + FILE *file; + long utime, stime; + int fields; + + snprintf(path, sizeof(path), "/proc/%d/stat", pid); + file = fopen(path, "r"); + if (file == NULL) { + perror("Failed to open stat file"); + return -1; + } + + /* Skip the first 13 fields and read the 14th and 15th */ + fields = fscanf(file, + "%*d %*s %*c %*d %*d %*d %*d %*d %*u %*u %*u %*u %*u %lu %lu", + &utime, &stime); + fclose(file); + + if (fields != 2) { + fprintf(stderr, "Failed to read stat file\n"); + return -1; + } + + /* Calculate the total time spent in the process */ + long total_time = utime + stime; + long ticks_per_second = sysconf(_SC_CLK_TCK); + float runtime_seconds = total_time * 1.0 / ticks_per_second; + + return runtime_seconds; +} + +static enum scx_test_status setup(void **ctx) +{ + struct rt_stall *skel; + + skel = rt_stall__open(); + SCX_FAIL_IF(!skel, "Failed to open"); + SCX_ENUM_INIT(skel); + SCX_FAIL_IF(rt_stall__load(skel), "Failed to load skel"); + + *ctx = skel; + + return SCX_TEST_PASS; +} + +static bool sched_stress_test(void) +{ + float cfs_runtime, rt_runtime; + int cfs_pid, rt_pid; + float expected_min_ratio = 0.04; /* 4% */ + + ksft_print_header(); + ksft_set_plan(1); + + /* Create and set up a EXT task */ + cfs_pid = fork(); + if (cfs_pid == 0) { + set_affinity(CORE_ID); + process_func(); + exit(0); + } else if (cfs_pid < 0) { + perror("fork for EXT task"); + ksft_exit_fail(); + } + + /* Create an RT task */ + rt_pid = fork(); + if (rt_pid == 0) { + set_affinity(CORE_ID); + set_sched(SCHED_FIFO, 50); + process_func(); + exit(0); + } else if (rt_pid < 0) { + perror("fork for RT task"); + ksft_exit_fail(); + } + + /* Let the processes run for the specified time */ + sleep(RUN_TIME); + + /* Get runtime for the EXT task */ + cfs_runtime = get_process_runtime(cfs_pid); + if (cfs_runtime != -1) + ksft_print_msg("Runtime of EXT task (PID %d) is %f seconds\n", cfs_pid, cfs_runtime); + else + ksft_exit_fail_msg("Error getting runtime for EXT task (PID %d)\n", cfs_pid); + + /* Get runtime for the RT task */ + rt_runtime = get_process_runtime(rt_pid); + if (rt_runtime != -1) + ksft_print_msg("Runtime of RT task (PID %d) is %f seconds\n", rt_pid, rt_runtime); + else + ksft_exit_fail_msg("Error getting runtime for RT task (PID %d)\n", rt_pid); + + /* Kill the processes */ + kill(cfs_pid, SIGKILL); + kill(rt_pid, SIGKILL); + waitpid(cfs_pid, NULL, 0); + waitpid(rt_pid, NULL, 0); + + /* Verify that the scx task got enough runtime */ + float actual_ratio = cfs_runtime / (cfs_runtime + rt_runtime); + ksft_print_msg("EXT task got %.2f%% of total runtime\n", actual_ratio * 100); + + if (actual_ratio >= expected_min_ratio) { + ksft_test_result_pass("PASS: EXT task got more than %.2f%% of runtime\n", + expected_min_ratio * 100); + return true; + } else { + ksft_test_result_fail("FAIL: EXT task got less than %.2f%% of runtime\n", + expected_min_ratio * 100); + return false; + } +} + +static enum scx_test_status run(void *ctx) +{ + struct rt_stall *skel = ctx; + struct bpf_link *link; + bool res; + + link = bpf_map__attach_struct_ops(skel->maps.rt_stall_ops); + SCX_FAIL_IF(!link, "Failed to attach scheduler"); + + res = sched_stress_test(); + + SCX_EQ(skel->data->uei.kind, EXIT_KIND(SCX_EXIT_NONE)); + bpf_link__destroy(link); + + if (!res) + ksft_exit_fail(); + + return SCX_TEST_PASS; +} + +static void cleanup(void *ctx) +{ + struct rt_stall *skel = ctx; + + rt_stall__destroy(skel); +} + +struct scx_test rt_stall = { + .name = "rt_stall", + .description = "Verify that RT tasks cannot stall SCHED_EXT tasks", + .setup = setup, + .run = run, + .cleanup = cleanup, +}; +REGISTER_SCX_TEST(&rt_stall)