diff options
Diffstat (limited to 'tools/testing/selftests/sched_ext/init_enable_count.c')
| -rw-r--r-- | tools/testing/selftests/sched_ext/init_enable_count.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/tools/testing/selftests/sched_ext/init_enable_count.c b/tools/testing/selftests/sched_ext/init_enable_count.c new file mode 100644 index 000000000000..eddf9e0e26e7 --- /dev/null +++ b/tools/testing/selftests/sched_ext/init_enable_count.c @@ -0,0 +1,157 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2023 Meta Platforms, Inc. and affiliates. + * Copyright (c) 2023 David Vernet <dvernet@meta.com> + * Copyright (c) 2023 Tejun Heo <tj@kernel.org> + */ +#include <stdio.h> +#include <unistd.h> +#include <sched.h> +#include <bpf/bpf.h> +#include <scx/common.h> +#include <sys/wait.h> +#include "scx_test.h" +#include "init_enable_count.bpf.skel.h" + +#define SCHED_EXT 7 + +static enum scx_test_status run_test(bool global) +{ + struct init_enable_count *skel; + struct bpf_link *link; + const u32 num_children = 5, num_pre_forks = 1024; + int ret, i, status; + struct sched_param param = {}; + pid_t pids[num_pre_forks]; + + skel = init_enable_count__open(); + SCX_FAIL_IF(!skel, "Failed to open"); + SCX_ENUM_INIT(skel); + + if (!global) + skel->struct_ops.init_enable_count_ops->flags |= SCX_OPS_SWITCH_PARTIAL; + + SCX_FAIL_IF(init_enable_count__load(skel), "Failed to load skel"); + + /* + * Fork a bunch of children before we attach the scheduler so that we + * ensure (at least in practical terms) that there are more tasks that + * transition from SCHED_OTHER -> SCHED_EXT than there are tasks that + * take the fork() path either below or in other processes. + */ + for (i = 0; i < num_pre_forks; i++) { + pids[i] = fork(); + SCX_FAIL_IF(pids[i] < 0, "Failed to fork child"); + if (pids[i] == 0) { + sleep(1); + exit(0); + } + } + + link = bpf_map__attach_struct_ops(skel->maps.init_enable_count_ops); + SCX_FAIL_IF(!link, "Failed to attach struct_ops"); + + for (i = 0; i < num_pre_forks; i++) { + SCX_FAIL_IF(waitpid(pids[i], &status, 0) != pids[i], + "Failed to wait for pre-forked child\n"); + + SCX_FAIL_IF(status != 0, "Pre-forked child %d exited with status %d\n", i, + status); + } + + bpf_link__destroy(link); + SCX_GE(skel->bss->init_task_cnt, num_pre_forks); + SCX_GE(skel->bss->exit_task_cnt, num_pre_forks); + + link = bpf_map__attach_struct_ops(skel->maps.init_enable_count_ops); + SCX_FAIL_IF(!link, "Failed to attach struct_ops"); + + /* SCHED_EXT children */ + for (i = 0; i < num_children; i++) { + pids[i] = fork(); + SCX_FAIL_IF(pids[i] < 0, "Failed to fork child"); + + if (pids[i] == 0) { + ret = sched_setscheduler(0, SCHED_EXT, ¶m); + SCX_BUG_ON(ret, "Failed to set sched to sched_ext"); + + /* + * Reset to SCHED_OTHER for half of them. Counts for + * everything should still be the same regardless, as + * ops.disable() is invoked even if a task is still on + * SCHED_EXT before it exits. + */ + if (i % 2 == 0) { + ret = sched_setscheduler(0, SCHED_OTHER, ¶m); + SCX_BUG_ON(ret, "Failed to reset sched to normal"); + } + exit(0); + } + } + for (i = 0; i < num_children; i++) { + SCX_FAIL_IF(waitpid(pids[i], &status, 0) != pids[i], + "Failed to wait for SCX child\n"); + + SCX_FAIL_IF(status != 0, "SCX child %d exited with status %d\n", i, + status); + } + + /* SCHED_OTHER children */ + for (i = 0; i < num_children; i++) { + pids[i] = fork(); + if (pids[i] == 0) + exit(0); + } + + for (i = 0; i < num_children; i++) { + SCX_FAIL_IF(waitpid(pids[i], &status, 0) != pids[i], + "Failed to wait for normal child\n"); + + SCX_FAIL_IF(status != 0, "Normal child %d exited with status %d\n", i, + status); + } + + bpf_link__destroy(link); + + SCX_GE(skel->bss->init_task_cnt, 2 * num_children); + SCX_GE(skel->bss->exit_task_cnt, 2 * num_children); + + if (global) { + SCX_GE(skel->bss->enable_cnt, 2 * num_children); + SCX_GE(skel->bss->disable_cnt, 2 * num_children); + } else { + SCX_EQ(skel->bss->enable_cnt, num_children); + SCX_EQ(skel->bss->disable_cnt, num_children); + } + /* + * We forked a ton of tasks before we attached the scheduler above, so + * this should be fine. Technically it could be flaky if a ton of forks + * are happening at the same time in other processes, but that should + * be exceedingly unlikely. + */ + SCX_GT(skel->bss->init_transition_cnt, skel->bss->init_fork_cnt); + SCX_GE(skel->bss->init_fork_cnt, 2 * num_children); + + init_enable_count__destroy(skel); + + return SCX_TEST_PASS; +} + +static enum scx_test_status run(void *ctx) +{ + enum scx_test_status status; + + status = run_test(true); + if (status != SCX_TEST_PASS) + return status; + + return run_test(false); +} + +struct scx_test init_enable_count = { + .name = "init_enable_count", + .description = "Verify we correctly count the occurrences of init, " + "enable, etc callbacks.", + .run = run, +}; +REGISTER_SCX_TEST(&init_enable_count) |