From: Emil Tsalapatis Date: Fri, 23 Jan 2026 03:26:03 +0000 (-0500) Subject: tools/sched_ext: add scx_userland scheduler X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cc4448d0856d424e52b5f53b2592575598233eac;p=thirdparty%2Fkernel%2Flinux.git tools/sched_ext: add scx_userland scheduler Add in the scx_userland scheduler that does vruntime-based scheduling in userspace code and communicates scheduling decisions to BPF by accessing and modifying globals through the skeleton. Cc: Tejun Heo Cc: David Vernet Signed-off-by: Emil Tsalapatis Signed-off-by: Tejun Heo --- diff --git a/tools/sched_ext/Makefile b/tools/sched_ext/Makefile index e4bda24740607..12043a82a1a90 100644 --- a/tools/sched_ext/Makefile +++ b/tools/sched_ext/Makefile @@ -189,7 +189,7 @@ $(INCLUDE_DIR)/%.bpf.skel.h: $(SCXOBJ_DIR)/%.bpf.o $(INCLUDE_DIR)/vmlinux.h $(BP SCX_COMMON_DEPS := include/scx/common.h include/scx/user_exit_info.h | $(BINDIR) -c-sched-targets = scx_simple scx_cpu0 scx_qmap scx_central scx_flatcg +c-sched-targets = scx_simple scx_cpu0 scx_qmap scx_central scx_flatcg scx_userland $(addprefix $(BINDIR)/,$(c-sched-targets)): \ $(BINDIR)/%: \ diff --git a/tools/sched_ext/scx_userland.bpf.c b/tools/sched_ext/scx_userland.bpf.c new file mode 100644 index 0000000000000..f29862b89386b --- /dev/null +++ b/tools/sched_ext/scx_userland.bpf.c @@ -0,0 +1,344 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * A minimal userland scheduler. + * + * In terms of scheduling, this provides two different types of behaviors: + * 1. A global FIFO scheduling order for _any_ tasks that have CPU affinity. + * All such tasks are direct-dispatched from the kernel, and are never + * enqueued in user space. + * 2. A primitive vruntime scheduler that is implemented in user space, for all + * other tasks. + * + * Some parts of this example user space scheduler could be implemented more + * efficiently using more complex and sophisticated data structures. For + * example, rather than using BPF_MAP_TYPE_QUEUE's, + * BPF_MAP_TYPE_{USER_}RINGBUF's could be used for exchanging messages between + * user space and kernel space. Similarly, we use a simple vruntime-sorted list + * in user space, but an rbtree could be used instead. + * + * Copyright (c) 2022 Meta Platforms, Inc. and affiliates. + * Copyright (c) 2022 Tejun Heo + * Copyright (c) 2022 David Vernet + */ +#include +#include "scx_userland.h" + +/* + * Maximum amount of tasks enqueued/dispatched between kernel and user-space. + */ +#define MAX_ENQUEUED_TASKS 4096 + +char _license[] SEC("license") = "GPL"; + +const volatile s32 usersched_pid; + +/* !0 for veristat, set during init */ +const volatile u32 num_possible_cpus = 64; + +/* Stats that are printed by user space. */ +u64 nr_failed_enqueues, nr_kernel_enqueues, nr_user_enqueues; + +/* + * Number of tasks that are queued for scheduling. + * + * This number is incremented by the BPF component when a task is queued to the + * user-space scheduler and it must be decremented by the user-space scheduler + * when a task is consumed. + */ +volatile u64 nr_queued; + +/* + * Number of tasks that are waiting for scheduling. + * + * This number must be updated by the user-space scheduler to keep track if + * there is still some scheduling work to do. + */ +volatile u64 nr_scheduled; + +UEI_DEFINE(uei); + +/* + * The map containing tasks that are enqueued in user space from the kernel. + * + * This map is drained by the user space scheduler. + */ +struct { + __uint(type, BPF_MAP_TYPE_QUEUE); + __uint(max_entries, MAX_ENQUEUED_TASKS); + __type(value, struct scx_userland_enqueued_task); +} enqueued SEC(".maps"); + +/* + * The map containing tasks that are dispatched to the kernel from user space. + * + * Drained by the kernel in userland_dispatch(). + */ +struct { + __uint(type, BPF_MAP_TYPE_QUEUE); + __uint(max_entries, MAX_ENQUEUED_TASKS); + __type(value, s32); +} dispatched SEC(".maps"); + +/* Per-task scheduling context */ +struct task_ctx { + bool force_local; /* Dispatch directly to local DSQ */ +}; + +/* Map that contains task-local storage. */ +struct { + __uint(type, BPF_MAP_TYPE_TASK_STORAGE); + __uint(map_flags, BPF_F_NO_PREALLOC); + __type(key, int); + __type(value, struct task_ctx); +} task_ctx_stor SEC(".maps"); + +/* + * Flag used to wake-up the user-space scheduler. + */ +static volatile u32 usersched_needed; + +/* + * Set user-space scheduler wake-up flag (equivalent to an atomic release + * operation). + */ +static void set_usersched_needed(void) +{ + __sync_fetch_and_or(&usersched_needed, 1); +} + +/* + * Check and clear user-space scheduler wake-up flag (equivalent to an atomic + * acquire operation). + */ +static bool test_and_clear_usersched_needed(void) +{ + return __sync_fetch_and_and(&usersched_needed, 0) == 1; +} + +static bool is_usersched_task(const struct task_struct *p) +{ + return p->pid == usersched_pid; +} + +static bool keep_in_kernel(const struct task_struct *p) +{ + return p->nr_cpus_allowed < num_possible_cpus; +} + +static struct task_struct *usersched_task(void) +{ + struct task_struct *p; + + p = bpf_task_from_pid(usersched_pid); + /* + * Should never happen -- the usersched task should always be managed + * by sched_ext. + */ + if (!p) + scx_bpf_error("Failed to find usersched task %d", usersched_pid); + + return p; +} + +s32 BPF_STRUCT_OPS(userland_select_cpu, struct task_struct *p, + s32 prev_cpu, u64 wake_flags) +{ + if (keep_in_kernel(p)) { + s32 cpu; + struct task_ctx *tctx; + + tctx = bpf_task_storage_get(&task_ctx_stor, p, 0, 0); + if (!tctx) { + scx_bpf_error("Failed to look up task-local storage for %s", p->comm); + return -ESRCH; + } + + if (p->nr_cpus_allowed == 1 || + scx_bpf_test_and_clear_cpu_idle(prev_cpu)) { + tctx->force_local = true; + return prev_cpu; + } + + cpu = scx_bpf_pick_idle_cpu(p->cpus_ptr, 0); + if (cpu >= 0) { + tctx->force_local = true; + return cpu; + } + } + + return prev_cpu; +} + +static void dispatch_user_scheduler(void) +{ + struct task_struct *p; + + p = usersched_task(); + if (p) { + scx_bpf_dsq_insert(p, SCX_DSQ_GLOBAL, SCX_SLICE_DFL, 0); + bpf_task_release(p); + } +} + +static void enqueue_task_in_user_space(struct task_struct *p, u64 enq_flags) +{ + struct scx_userland_enqueued_task task = {}; + + task.pid = p->pid; + task.sum_exec_runtime = p->se.sum_exec_runtime; + task.weight = p->scx.weight; + + if (bpf_map_push_elem(&enqueued, &task, 0)) { + /* + * If we fail to enqueue the task in user space, put it + * directly on the global DSQ. + */ + __sync_fetch_and_add(&nr_failed_enqueues, 1); + scx_bpf_dsq_insert(p, SCX_DSQ_GLOBAL, SCX_SLICE_DFL, enq_flags); + } else { + __sync_fetch_and_add(&nr_user_enqueues, 1); + set_usersched_needed(); + } +} + +void BPF_STRUCT_OPS(userland_enqueue, struct task_struct *p, u64 enq_flags) +{ + if (keep_in_kernel(p)) { + u64 dsq_id = SCX_DSQ_GLOBAL; + struct task_ctx *tctx; + + tctx = bpf_task_storage_get(&task_ctx_stor, p, 0, 0); + if (!tctx) { + scx_bpf_error("Failed to lookup task ctx for %s", p->comm); + return; + } + + if (tctx->force_local) + dsq_id = SCX_DSQ_LOCAL; + tctx->force_local = false; + scx_bpf_dsq_insert(p, dsq_id, SCX_SLICE_DFL, enq_flags); + __sync_fetch_and_add(&nr_kernel_enqueues, 1); + return; + } else if (!is_usersched_task(p)) { + enqueue_task_in_user_space(p, enq_flags); + } +} + +void BPF_STRUCT_OPS(userland_dispatch, s32 cpu, struct task_struct *prev) +{ + if (test_and_clear_usersched_needed()) + dispatch_user_scheduler(); + + bpf_repeat(MAX_ENQUEUED_TASKS) { + s32 pid; + struct task_struct *p; + + if (bpf_map_pop_elem(&dispatched, &pid)) + break; + + /* + * The task could have exited by the time we get around to + * dispatching it. Treat this as a normal occurrence, and simply + * move onto the next iteration. + */ + p = bpf_task_from_pid(pid); + if (!p) + continue; + + scx_bpf_dsq_insert(p, SCX_DSQ_GLOBAL, SCX_SLICE_DFL, 0); + bpf_task_release(p); + } +} + +/* + * A CPU is about to change its idle state. If the CPU is going idle, ensure + * that the user-space scheduler has a chance to run if there is any remaining + * work to do. + */ +void BPF_STRUCT_OPS(userland_update_idle, s32 cpu, bool idle) +{ + /* + * Don't do anything if we exit from and idle state, a CPU owner will + * be assigned in .running(). + */ + if (!idle) + return; + /* + * A CPU is now available, notify the user-space scheduler that tasks + * can be dispatched, if there is at least one task waiting to be + * scheduled, either queued (accounted in nr_queued) or scheduled + * (accounted in nr_scheduled). + * + * NOTE: nr_queued is incremented by the BPF component, more exactly in + * enqueue(), when a task is sent to the user-space scheduler, then + * the scheduler drains the queued tasks (updating nr_queued) and adds + * them to its internal data structures / state; at this point tasks + * become "scheduled" and the user-space scheduler will take care of + * updating nr_scheduled accordingly; lastly tasks will be dispatched + * and the user-space scheduler will update nr_scheduled again. + * + * Checking both counters allows to determine if there is still some + * pending work to do for the scheduler: new tasks have been queued + * since last check, or there are still tasks "queued" or "scheduled" + * since the previous user-space scheduler run. If the counters are + * both zero it is pointless to wake-up the scheduler (even if a CPU + * becomes idle), because there is nothing to do. + * + * Keep in mind that update_idle() doesn't run concurrently with the + * user-space scheduler (that is single-threaded): this function is + * naturally serialized with the user-space scheduler code, therefore + * this check here is also safe from a concurrency perspective. + */ + if (nr_queued || nr_scheduled) { + /* + * Kick the CPU to make it immediately ready to accept + * dispatched tasks. + */ + set_usersched_needed(); + scx_bpf_kick_cpu(cpu, 0); + } +} + +s32 BPF_STRUCT_OPS(userland_init_task, struct task_struct *p, + struct scx_init_task_args *args) +{ + if (bpf_task_storage_get(&task_ctx_stor, p, 0, + BPF_LOCAL_STORAGE_GET_F_CREATE)) + return 0; + else + return -ENOMEM; +} + +s32 BPF_STRUCT_OPS(userland_init) +{ + if (num_possible_cpus == 0) { + scx_bpf_error("User scheduler # CPUs uninitialized (%d)", + num_possible_cpus); + return -EINVAL; + } + + if (usersched_pid <= 0) { + scx_bpf_error("User scheduler pid uninitialized (%d)", + usersched_pid); + return -EINVAL; + } + + return 0; +} + +void BPF_STRUCT_OPS(userland_exit, struct scx_exit_info *ei) +{ + UEI_RECORD(uei, ei); +} + +SCX_OPS_DEFINE(userland_ops, + .select_cpu = (void *)userland_select_cpu, + .enqueue = (void *)userland_enqueue, + .dispatch = (void *)userland_dispatch, + .update_idle = (void *)userland_update_idle, + .init_task = (void *)userland_init_task, + .init = (void *)userland_init, + .exit = (void *)userland_exit, + .flags = SCX_OPS_ENQ_LAST | + SCX_OPS_KEEP_BUILTIN_IDLE, + .name = "userland"); diff --git a/tools/sched_ext/scx_userland.c b/tools/sched_ext/scx_userland.c new file mode 100644 index 0000000000000..10b31020f44f0 --- /dev/null +++ b/tools/sched_ext/scx_userland.c @@ -0,0 +1,437 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * A demo sched_ext user space scheduler which provides vruntime semantics + * using a simple ordered-list implementation. + * + * Each CPU in the system resides in a single, global domain. This precludes + * the need to do any load balancing between domains. The scheduler could + * easily be extended to support multiple domains, with load balancing + * happening in user space. + * + * Any task which has any CPU affinity is scheduled entirely in BPF. This + * program only schedules tasks which may run on any CPU. + * + * Copyright (c) 2022 Meta Platforms, Inc. and affiliates. + * Copyright (c) 2022 Tejun Heo + * Copyright (c) 2022 David Vernet + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include "scx_userland.h" +#include "scx_userland.bpf.skel.h" + +const char help_fmt[] = +"A minimal userland sched_ext scheduler.\n" +"\n" +"See the top-level comment in .bpf.c for more details.\n" +"\n" +"Try to reduce `sysctl kernel.pid_max` if this program triggers OOMs.\n" +"\n" +"Usage: %s [-b BATCH]\n" +"\n" +" -b BATCH The number of tasks to batch when dispatching (default: 8)\n" +" -v Print libbpf debug messages\n" +" -h Display this help and exit\n"; + +/* Defined in UAPI */ +#define SCHED_EXT 7 + +/* Number of tasks to batch when dispatching to user space. */ +static __u32 batch_size = 8; + +static bool verbose; +static volatile int exit_req; +static int enqueued_fd, dispatched_fd; + +static struct scx_userland *skel; +static struct bpf_link *ops_link; + +/* Stats collected in user space. */ +static __u64 nr_vruntime_enqueues, nr_vruntime_dispatches, nr_vruntime_failed; + +/* Number of tasks currently enqueued. */ +static __u64 nr_curr_enqueued; + +/* The data structure containing tasks that are enqueued in user space. */ +struct enqueued_task { + LIST_ENTRY(enqueued_task) entries; + __u64 sum_exec_runtime; + double vruntime; +}; + +/* + * Use a vruntime-sorted list to store tasks. This could easily be extended to + * a more optimal data structure, such as an rbtree as is done in CFS. We + * currently elect to use a sorted list to simplify the example for + * illustrative purposes. + */ +LIST_HEAD(listhead, enqueued_task); + +/* + * A vruntime-sorted list of tasks. The head of the list contains the task with + * the lowest vruntime. That is, the task that has the "highest" claim to be + * scheduled. + */ +static struct listhead vruntime_head = LIST_HEAD_INITIALIZER(vruntime_head); + +/* + * The main array of tasks. The array is allocated all at once during + * initialization, based on /proc/sys/kernel/pid_max, to avoid having to + * dynamically allocate memory on the enqueue path, which could cause a + * deadlock. A more substantive user space scheduler could e.g. provide a hook + * for newly enabled tasks that are passed to the scheduler from the + * .prep_enable() callback to allows the scheduler to allocate on safe paths. + */ +struct enqueued_task *tasks; +static int pid_max; + +static double min_vruntime; + +static int libbpf_print_fn(enum libbpf_print_level level, const char *format, va_list args) +{ + if (level == LIBBPF_DEBUG && !verbose) + return 0; + return vfprintf(stderr, format, args); +} + +static void sigint_handler(int userland) +{ + exit_req = 1; +} + +static int get_pid_max(void) +{ + FILE *fp; + int pid_max; + + fp = fopen("/proc/sys/kernel/pid_max", "r"); + if (fp == NULL) { + fprintf(stderr, "Error opening /proc/sys/kernel/pid_max\n"); + return -1; + } + if (fscanf(fp, "%d", &pid_max) != 1) { + fprintf(stderr, "Error reading from /proc/sys/kernel/pid_max\n"); + fclose(fp); + return -1; + } + fclose(fp); + + return pid_max; +} + +static int init_tasks(void) +{ + pid_max = get_pid_max(); + if (pid_max < 0) + return pid_max; + + tasks = calloc(pid_max, sizeof(*tasks)); + if (!tasks) { + fprintf(stderr, "Error allocating tasks array\n"); + return -ENOMEM; + } + + return 0; +} + +static __u32 task_pid(const struct enqueued_task *task) +{ + return ((uintptr_t)task - (uintptr_t)tasks) / sizeof(*task); +} + +static int dispatch_task(__s32 pid) +{ + int err; + + err = bpf_map_update_elem(dispatched_fd, NULL, &pid, 0); + if (err) { + nr_vruntime_failed++; + } else { + nr_vruntime_dispatches++; + } + + return err; +} + +static struct enqueued_task *get_enqueued_task(__s32 pid) +{ + if (pid >= pid_max) + return NULL; + + return &tasks[pid]; +} + +static double calc_vruntime_delta(__u64 weight, __u64 delta) +{ + double weight_f = (double)weight / 100.0; + double delta_f = (double)delta; + + return delta_f / weight_f; +} + +static void update_enqueued(struct enqueued_task *enqueued, const struct scx_userland_enqueued_task *bpf_task) +{ + __u64 delta; + + delta = bpf_task->sum_exec_runtime - enqueued->sum_exec_runtime; + + enqueued->vruntime += calc_vruntime_delta(bpf_task->weight, delta); + if (min_vruntime > enqueued->vruntime) + enqueued->vruntime = min_vruntime; + enqueued->sum_exec_runtime = bpf_task->sum_exec_runtime; +} + +static int vruntime_enqueue(const struct scx_userland_enqueued_task *bpf_task) +{ + struct enqueued_task *curr, *enqueued, *prev; + + curr = get_enqueued_task(bpf_task->pid); + if (!curr) + return ENOENT; + + update_enqueued(curr, bpf_task); + nr_vruntime_enqueues++; + nr_curr_enqueued++; + + /* + * Enqueue the task in a vruntime-sorted list. A more optimal data + * structure such as an rbtree could easily be used as well. We elect + * to use a list here simply because it's less code, and thus the + * example is less convoluted and better serves to illustrate what a + * user space scheduler could look like. + */ + + if (LIST_EMPTY(&vruntime_head)) { + LIST_INSERT_HEAD(&vruntime_head, curr, entries); + return 0; + } + + LIST_FOREACH(enqueued, &vruntime_head, entries) { + if (curr->vruntime <= enqueued->vruntime) { + LIST_INSERT_BEFORE(enqueued, curr, entries); + return 0; + } + prev = enqueued; + } + + LIST_INSERT_AFTER(prev, curr, entries); + + return 0; +} + +static void drain_enqueued_map(void) +{ + while (1) { + struct scx_userland_enqueued_task task; + int err; + + if (bpf_map_lookup_and_delete_elem(enqueued_fd, NULL, &task)) { + skel->bss->nr_queued = 0; + skel->bss->nr_scheduled = nr_curr_enqueued; + return; + } + + err = vruntime_enqueue(&task); + if (err) { + fprintf(stderr, "Failed to enqueue task %d: %s\n", + task.pid, strerror(err)); + exit_req = 1; + return; + } + } +} + +static void dispatch_batch(void) +{ + __u32 i; + + for (i = 0; i < batch_size; i++) { + struct enqueued_task *task; + int err; + __s32 pid; + + task = LIST_FIRST(&vruntime_head); + if (!task) + break; + + min_vruntime = task->vruntime; + pid = task_pid(task); + LIST_REMOVE(task, entries); + err = dispatch_task(pid); + if (err) { + /* + * If we fail to dispatch, put the task back to the + * vruntime_head list and stop dispatching additional + * tasks in this batch. + */ + LIST_INSERT_HEAD(&vruntime_head, task, entries); + break; + } + nr_curr_enqueued--; + } + skel->bss->nr_scheduled = nr_curr_enqueued; +} + +static void *run_stats_printer(void *arg) +{ + while (!exit_req) { + __u64 nr_failed_enqueues, nr_kernel_enqueues, nr_user_enqueues, total; + + nr_failed_enqueues = skel->bss->nr_failed_enqueues; + nr_kernel_enqueues = skel->bss->nr_kernel_enqueues; + nr_user_enqueues = skel->bss->nr_user_enqueues; + total = nr_failed_enqueues + nr_kernel_enqueues + nr_user_enqueues; + + printf("o-----------------------o\n"); + printf("| BPF ENQUEUES |\n"); + printf("|-----------------------|\n"); + printf("| kern: %10llu |\n", nr_kernel_enqueues); + printf("| user: %10llu |\n", nr_user_enqueues); + printf("| failed: %10llu |\n", nr_failed_enqueues); + printf("| -------------------- |\n"); + printf("| total: %10llu |\n", total); + printf("| |\n"); + printf("|-----------------------|\n"); + printf("| VRUNTIME / USER |\n"); + printf("|-----------------------|\n"); + printf("| enq: %10llu |\n", nr_vruntime_enqueues); + printf("| disp: %10llu |\n", nr_vruntime_dispatches); + printf("| failed: %10llu |\n", nr_vruntime_failed); + printf("o-----------------------o\n"); + printf("\n\n"); + fflush(stdout); + sleep(1); + } + + return NULL; +} + +static int spawn_stats_thread(void) +{ + pthread_t stats_printer; + + return pthread_create(&stats_printer, NULL, run_stats_printer, NULL); +} + +static void pre_bootstrap(int argc, char **argv) +{ + int err; + __u32 opt; + struct sched_param sched_param = { + .sched_priority = sched_get_priority_max(SCHED_EXT), + }; + + err = init_tasks(); + if (err) + exit(err); + + libbpf_set_print(libbpf_print_fn); + signal(SIGINT, sigint_handler); + signal(SIGTERM, sigint_handler); + + /* + * Enforce that the user scheduler task is managed by sched_ext. The + * task eagerly drains the list of enqueued tasks in its main work + * loop, and then yields the CPU. The BPF scheduler only schedules the + * user space scheduler task when at least one other task in the system + * needs to be scheduled. + */ + err = syscall(__NR_sched_setscheduler, getpid(), SCHED_EXT, &sched_param); + SCX_BUG_ON(err, "Failed to set scheduler to SCHED_EXT"); + + while ((opt = getopt(argc, argv, "b:vh")) != -1) { + switch (opt) { + case 'b': + batch_size = strtoul(optarg, NULL, 0); + break; + case 'v': + verbose = true; + break; + default: + fprintf(stderr, help_fmt, basename(argv[0])); + exit(opt != 'h'); + } + } + + /* + * It's not always safe to allocate in a user space scheduler, as an + * enqueued task could hold a lock that we require in order to be able + * to allocate. + */ + err = mlockall(MCL_CURRENT | MCL_FUTURE); + SCX_BUG_ON(err, "Failed to prefault and lock address space"); +} + +static void bootstrap(char *comm) +{ + skel = SCX_OPS_OPEN(userland_ops, scx_userland); + + skel->rodata->num_possible_cpus = libbpf_num_possible_cpus(); + assert(skel->rodata->num_possible_cpus > 0); + skel->rodata->usersched_pid = getpid(); + assert(skel->rodata->usersched_pid > 0); + + SCX_OPS_LOAD(skel, userland_ops, scx_userland, uei); + + enqueued_fd = bpf_map__fd(skel->maps.enqueued); + dispatched_fd = bpf_map__fd(skel->maps.dispatched); + assert(enqueued_fd > 0); + assert(dispatched_fd > 0); + + SCX_BUG_ON(spawn_stats_thread(), "Failed to spawn stats thread"); + + ops_link = SCX_OPS_ATTACH(skel, userland_ops, scx_userland); +} + +static void sched_main_loop(void) +{ + while (!exit_req) { + /* + * Perform the following work in the main user space scheduler + * loop: + * + * 1. Drain all tasks from the enqueued map, and enqueue them + * to the vruntime sorted list. + * + * 2. Dispatch a batch of tasks from the vruntime sorted list + * down to the kernel. + * + * 3. Yield the CPU back to the system. The BPF scheduler will + * reschedule the user space scheduler once another task has + * been enqueued to user space. + */ + drain_enqueued_map(); + dispatch_batch(); + sched_yield(); + } +} + +int main(int argc, char **argv) +{ + __u64 ecode; + + pre_bootstrap(argc, argv); +restart: + bootstrap(argv[0]); + sched_main_loop(); + + exit_req = 1; + bpf_link__destroy(ops_link); + ecode = UEI_REPORT(skel, uei); + scx_userland__destroy(skel); + + if (UEI_ECODE_RESTART(ecode)) + goto restart; + return 0; +} diff --git a/tools/sched_ext/scx_userland.h b/tools/sched_ext/scx_userland.h new file mode 100644 index 0000000000000..684fb2dd5de96 --- /dev/null +++ b/tools/sched_ext/scx_userland.h @@ -0,0 +1,17 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2022 Meta, Inc */ + +#ifndef __SCX_USERLAND_COMMON_H +#define __SCX_USERLAND_COMMON_H + +/* + * An instance of a task that has been enqueued by the kernel for consumption + * by a user space global scheduler thread. + */ +struct scx_userland_enqueued_task { + __s32 pid; + u64 sum_exec_runtime; + u64 weight; +}; + +#endif // __SCX_USERLAND_COMMON_H