ladybird/Userland/Libraries/LibC/sched.cpp
kleines Filmröllchen 6dded99777 Kernel+LibC: Report correct scheduling priority limits
The priority range was changed several years ago, but the
userland-reported limits were just forgotten :skeleyak:. Move the thread
priority constants into an API header so that userland can use it
properly.
2022-10-27 11:30:19 +01:00

57 lines
1.6 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <errno.h>
#include <sched.h>
#include <syscall.h>
extern "C" {
// https://pubs.opengroup.org/onlinepubs/9699919799/functions/sched_yield.html
int sched_yield()
{
int rc = syscall(SC_yield);
__RETURN_WITH_ERRNO(rc, rc, -1);
}
// https://pubs.opengroup.org/onlinepubs/9699919799/functions/sched_get_priority_min.html
int sched_get_priority_min([[maybe_unused]] int policy)
{
return THREAD_PRIORITY_MIN;
}
// https://pubs.opengroup.org/onlinepubs/9699919799/functions/sched_get_priority_max.html
int sched_get_priority_max([[maybe_unused]] int policy)
{
return THREAD_PRIORITY_MAX;
}
// https://pubs.opengroup.org/onlinepubs/9699919799/functions/sched_setparam.html
int sched_setparam(pid_t pid, const struct sched_param* param)
{
Syscall::SC_scheduler_parameters_params parameters {
.pid_or_tid = pid,
.mode = Syscall::SchedulerParametersMode::Process,
.parameters = *param,
};
int rc = syscall(SC_scheduler_set_parameters, &parameters);
__RETURN_WITH_ERRNO(rc, rc, -1);
}
// https://pubs.opengroup.org/onlinepubs/9699919799/functions/sched_getparam.html
int sched_getparam(pid_t pid, struct sched_param* param)
{
Syscall::SC_scheduler_parameters_params parameters {
.pid_or_tid = pid,
.mode = Syscall::SchedulerParametersMode::Process,
.parameters = {},
};
int rc = syscall(SC_scheduler_get_parameters, &parameters);
if (rc == 0)
*param = parameters.parameters;
__RETURN_WITH_ERRNO(rc, rc, -1);
}
}