Commit e764295a authored by Andrea Righi's avatar Andrea Righi Committed by Tejun Heo
Browse files

selftests/sched_ext: Add test for scx_bpf_select_cpu_and() via test_run 



Update the allowed_cpus selftest to include a check to validate the
behavior of scx_bpf_select_cpu_and() when invoked via a BPF test_run
call.

Signed-off-by: default avatarAndrea Righi <arighi@nvidia.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent 4ac760bd

tools/testing/selftests/sched_ext/allowed_cpus.bpf.c

+23 −0
Original line number Diff line number Diff line
@@ -111,6 +111,29 @@ void BPF_STRUCT_OPS(allowed_cpus_exit, struct scx_exit_info *ei) 
	UEI_RECORD(uei, ei);

}



struct task_cpu_arg {

	pid_t pid;

};



SEC("syscall")

int select_cpu_from_user(struct task_cpu_arg *input)

{

	struct task_struct *p;

	int cpu;



	p = bpf_task_from_pid(input->pid);

	if (!p)

		return -EINVAL;



	bpf_rcu_read_lock();

	cpu = scx_bpf_select_cpu_and(p, bpf_get_smp_processor_id(), 0, p->cpus_ptr, 0);

	bpf_rcu_read_unlock();



	bpf_task_release(p);



	return cpu;

}



SEC(".struct_ops.link")

struct sched_ext_ops allowed_cpus_ops = {

	.select_cpu		= (void *)allowed_cpus_select_cpu,

tools/testing/selftests/sched_ext/allowed_cpus.c

+27 −0
Original line number Diff line number Diff line
@@ -23,6 +23,30 @@ static enum scx_test_status setup(void **ctx) 
	return SCX_TEST_PASS;

}



static int test_select_cpu_from_user(const struct allowed_cpus *skel)

{

	int fd, ret;

	__u64 args[1];



	LIBBPF_OPTS(bpf_test_run_opts, attr,

		.ctx_in = args,

		.ctx_size_in = sizeof(args),

	);



	args[0] = getpid();

	fd = bpf_program__fd(skel->progs.select_cpu_from_user);

	if (fd < 0)

		return fd;



	ret = bpf_prog_test_run_opts(fd, &attr);

	if (ret < 0)

		return ret;



	fprintf(stderr, "%s: CPU %d\n", __func__, attr.retval);



	return 0;

}



static enum scx_test_status run(void *ctx)

{

	struct allowed_cpus *skel = ctx;
@@ -31,6 +55,9 @@ static enum scx_test_status run(void *ctx) 
	link = bpf_map__attach_struct_ops(skel->maps.allowed_cpus_ops);

	SCX_FAIL_IF(!link, "Failed to attach scheduler");



	/* Pick an idle CPU from user-space */

	SCX_FAIL_IF(test_select_cpu_from_user(skel), "Failed to pick idle CPU");



	/* Just sleeping is fine, plenty of scheduling events happening */

	sleep(1);