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This tree adds the sched_set_fifo*() encapsulation APIs to remove

Browse source 
static priority level knowledge from non-scheduler code.
 
 The three APIs for non-scheduler code to set SCHED_FIFO are:
 
  - sched_set_fifo()
  - sched_set_fifo_low()
  - sched_set_normal()
 
 These are two FIFO priority levels: default (high), and a 'low' priority level,
 plus sched_set_normal() to set the policy back to non-SCHED_FIFO.
 
 Since the changes affect a lot of non-scheduler code, we kept this in a separate
 tree.
 
 When merging to the latest upstream tree there's a conflict in drivers/spi/spi.c,
 which can be resolved via:
 
 	sched_set_fifo(ctlr->kworker_task);
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'sched-fifo-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull sched/fifo updates from Ingo Molnar:
 "This adds the sched_set_fifo*() encapsulation APIs to remove static
  priority level knowledge from non-scheduler code.

  The three APIs for non-scheduler code to set SCHED_FIFO are:

   - sched_set_fifo()
   - sched_set_fifo_low()
   - sched_set_normal()

  These are two FIFO priority levels: default (high), and a 'low'
  priority level, plus sched_set_normal() to set the policy back to
  non-SCHED_FIFO.

  Since the changes affect a lot of non-scheduler code, we kept this in
  a separate tree"

* tag 'sched-fifo-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  sched,tracing: Convert to sched_set_fifo()
  sched: Remove sched_set_*() return value
  sched: Remove sched_setscheduler*() EXPORTs
  sched,psi: Convert to sched_set_fifo_low()
  sched,rcutorture: Convert to sched_set_fifo_low()
  sched,rcuperf: Convert to sched_set_fifo_low()
  sched,locktorture: Convert to sched_set_fifo()
  sched,irq: Convert to sched_set_fifo()
  sched,watchdog: Convert to sched_set_fifo()
  sched,serial: Convert to sched_set_fifo()
  sched,powerclamp: Convert to sched_set_fifo()
  sched,ion: Convert to sched_set_normal()
  sched,powercap: Convert to sched_set_fifo*()
  sched,spi: Convert to sched_set_fifo*()
  sched,mmc: Convert to sched_set_fifo*()
  sched,ivtv: Convert to sched_set_fifo*()
  sched,drm/scheduler: Convert to sched_set_fifo*()
  sched,msm: Convert to sched_set_fifo*()
  sched,psci: Convert to sched_set_fifo*()
  sched,drbd: Convert to sched_set_fifo*()
  ...
This commit is contained in:
Linus Torvalds 2020-08-06 11:55:43 -07:00
commit 6d2b84a4e5
25 changed files with 100 additions and 124 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

3
arch/arm/common/bL_switcher.c
View file

@ -270,12 +270,11 @@ static struct bL_thread bL_threads[NR_CPUS];
static int bL_switcher_thread(void *arg)
{
struct bL_thread *t = arg;
struct sched_param param = { .sched_priority = 1 };
int cluster;
bL_switch_completion_handler completer;
void *completer_cookie;
sched_setscheduler_nocheck(current, SCHED_FIFO, &param);
sched_set_fifo_low(current);
complete(&t->started);
do {

3
crypto/crypto_engine.c
View file

@ -482,7 +482,6 @@ struct crypto_engine *crypto_engine_alloc_init_and_set(struct device *dev,
int (*cbk_do_batch)(struct crypto_engine *engine),
bool rt, int qlen)
{
struct sched_param param = { .sched_priority = MAX_RT_PRIO / 2 };
struct crypto_engine *engine;
if (!dev)
@ -520,7 +519,7 @@ struct crypto_engine *crypto_engine_alloc_init_and_set(struct device *dev,
if (engine->rt) {
dev_info(dev, "will run requests pump with realtime priority\n");
sched_setscheduler(engine->kworker->task, SCHED_FIFO, &param);
sched_set_fifo(engine->kworker->task);
}
return engine;

3
drivers/acpi/acpi_pad.c
View file

@ -136,12 +136,11 @@ static unsigned int idle_pct = 5; /* percentage */
static unsigned int round_robin_time = 1; /* second */
static int power_saving_thread(void *data)
{
struct sched_param param = {.sched_priority = 1};
int do_sleep;
unsigned int tsk_index = (unsigned long)data;
u64 last_jiffies = 0;
sched_setscheduler(current, SCHED_RR, &param);
sched_set_fifo_low(current);
while (!kthread_should_stop()) {
unsigned long expire_time;

5
drivers/block/drbd/drbd_receiver.c
View file

@ -6019,11 +6019,8 @@ int drbd_ack_receiver(struct drbd_thread *thi)
unsigned int header_size = drbd_header_size(connection);
int expect = header_size;
bool ping_timeout_active = false;
struct sched_param param = { .sched_priority = 2 };
rv = sched_setscheduler(current, SCHED_RR, &param);
if (rv < 0)
drbd_err(connection, "drbd_ack_receiver: ERROR set priority, ret=%d\n", rv);
sched_set_fifo_low(current);
while (get_t_state(thi) == RUNNING) {
drbd_thread_current_set_cpu(thi);

10
drivers/firmware/psci/psci_checker.c
View file

@ -274,7 +274,6 @@ static int suspend_test_thread(void *arg)
{
int cpu = (long)arg;
int i, nb_suspend = 0, nb_shallow_sleep = 0, nb_err = 0;
struct sched_param sched_priority = { .sched_priority = MAX_RT_PRIO-1 };
struct cpuidle_device *dev;
struct cpuidle_driver *drv;
/* No need for an actual callback, we just want to wake up the CPU. */
@ -284,9 +283,7 @@ static int suspend_test_thread(void *arg)
wait_for_completion(&suspend_threads_started);
/* Set maximum priority to preempt all other threads on this CPU. */
if (sched_setscheduler_nocheck(current, SCHED_FIFO, &sched_priority))
pr_warn("Failed to set suspend thread scheduler on CPU %d\n",
cpu);
sched_set_fifo(current);
dev = this_cpu_read(cpuidle_devices);
drv = cpuidle_get_cpu_driver(dev);
@ -351,11 +348,6 @@ static int suspend_test_thread(void *arg)
if (atomic_dec_return_relaxed(&nb_active_threads) == 0)
complete(&suspend_threads_done);
/* Give up on RT scheduling and wait for termination. */
sched_priority.sched_priority = 0;
if (sched_setscheduler_nocheck(current, SCHED_NORMAL, &sched_priority))
pr_warn("Failed to set suspend thread scheduler on CPU %d\n",
cpu);
for (;;) {
/* Needs to be set first to avoid missing a wakeup. */
set_current_state(TASK_INTERRUPTIBLE);

6
drivers/gpu/drm/drm_vblank_work.c
View file

@ -248,9 +248,6 @@ EXPORT_SYMBOL(drm_vblank_work_init);
int drm_vblank_worker_init(struct drm_vblank_crtc *vblank)
{
struct sched_param param = {
.sched_priority = MAX_RT_PRIO - 1,
};
struct kthread_worker *worker;
INIT_LIST_HEAD(&vblank->pending_work);
@ -263,5 +260,6 @@ int drm_vblank_worker_init(struct drm_vblank_crtc *vblank)
vblank->worker = worker;
return sched_setscheduler(vblank->worker->task, SCHED_FIFO, &param);
sched_set_fifo(worker->task);
return 0;
}

13
drivers/gpu/drm/msm/msm_drv.c
View file

@ -401,7 +401,6 @@ static int msm_drm_init(struct device *dev, struct drm_driver *drv)
struct msm_kms *kms;
struct msm_mdss *mdss;
int ret, i;
struct sched_param param;
ddev = drm_dev_alloc(drv, dev);
if (IS_ERR(ddev)) {
@ -507,12 +506,6 @@ static int msm_drm_init(struct device *dev, struct drm_driver *drv)
ddev->mode_config.funcs = &mode_config_funcs;
ddev->mode_config.helper_private = &mode_config_helper_funcs;
/**
* this priority was found during empiric testing to have appropriate
* realtime scheduling to process display updates and interact with
* other real time and normal priority task
*/
param.sched_priority = 16;
for (i = 0; i < priv->num_crtcs; i++) {
/* initialize event thread */
priv->event_thread[i].crtc_id = priv->crtcs[i]->base.id;
@ -524,11 +517,7 @@ static int msm_drm_init(struct device *dev, struct drm_driver *drv)
goto err_msm_uninit;
}
ret = sched_setscheduler(priv->event_thread[i].worker->task,
SCHED_FIFO, &param);
if (ret)
dev_warn(dev, "event_thread set priority failed:%d\n",
ret);
sched_set_fifo(priv->event_thread[i].worker->task);
}
ret = drm_vblank_init(ddev, priv->num_crtcs);

3
drivers/gpu/drm/scheduler/sched_main.c
View file

@ -762,11 +762,10 @@ static bool drm_sched_blocked(struct drm_gpu_scheduler *sched)
*/
static int drm_sched_main(void *param)
{
struct sched_param sparam = {.sched_priority = 1};
struct drm_gpu_scheduler *sched = (struct drm_gpu_scheduler *)param;
int r;
sched_setscheduler(current, SCHED_FIFO, &sparam);
sched_set_fifo_low(current);
while (!kthread_should_stop()) {
struct drm_sched_entity *entity = NULL;

4
drivers/media/pci/ivtv/ivtv-driver.c
View file

@ -737,8 +737,6 @@ done:
*/
static int ivtv_init_struct1(struct ivtv *itv)
{
struct sched_param param = { .sched_priority = 99 };
itv->base_addr = pci_resource_start(itv->pdev, 0);
itv->enc_mbox.max_mbox = 2; /* the encoder has 3 mailboxes (0-2) */
itv->dec_mbox.max_mbox = 1; /* the decoder has 2 mailboxes (0-1) */
@ -758,7 +756,7 @@ static int ivtv_init_struct1(struct ivtv *itv)
return -1;
}
/* must use the FIFO scheduler as it is realtime sensitive */
sched_setscheduler(itv->irq_worker_task, SCHED_FIFO, &param);
sched_set_fifo(itv->irq_worker_task);
kthread_init_work(&itv->irq_work, ivtv_irq_work_handler);

3
drivers/mmc/core/sdio_irq.c
View file

@ -139,11 +139,10 @@ EXPORT_SYMBOL_GPL(sdio_signal_irq);
static int sdio_irq_thread(void *_host)
{
struct mmc_host *host = _host;
struct sched_param param = { .sched_priority = 1 };
unsigned long period, idle_period;
int ret;
sched_setscheduler(current, SCHED_FIFO, &param);
sched_set_fifo_low(current);
/*
* We want to allow for SDIO cards to work even on non SDIO

11
drivers/platform/chrome/cros_ec_spi.c
View file

@ -709,9 +709,6 @@ static void cros_ec_spi_high_pri_release(void *worker)
static int cros_ec_spi_devm_high_pri_alloc(struct device *dev,
struct cros_ec_spi *ec_spi)
{
struct sched_param sched_priority = {
.sched_priority = MAX_RT_PRIO / 2,
};
int err;
ec_spi->high_pri_worker =
@ -728,11 +725,9 @@ static int cros_ec_spi_devm_high_pri_alloc(struct device *dev,
if (err)
return err;
err = sched_setscheduler_nocheck(ec_spi->high_pri_worker->task,
SCHED_FIFO, &sched_priority);
if (err)
dev_err(dev, "Can't set cros_ec high pri priority: %d\n", err);
return err;
sched_set_fifo(ec_spi->high_pri_worker->task);
return 0;
}
static int cros_ec_spi_probe(struct spi_device *spi)

4
drivers/powercap/idle_inject.c
View file

@ -268,9 +268,7 @@ void idle_inject_stop(struct idle_inject_device *ii_dev)
*/
static void idle_inject_setup(unsigned int cpu)
{
struct sched_param param = { .sched_priority = MAX_USER_RT_PRIO / 2 };
sched_setscheduler(current, SCHED_FIFO, &param);
sched_set_fifo(current);
}
/**

4
drivers/spi/spi.c
View file

@ -1626,11 +1626,9 @@ EXPORT_SYMBOL_GPL(spi_take_timestamp_post);
*/
static void spi_set_thread_rt(struct spi_controller *ctlr)
{
struct sched_param param = { .sched_priority = MAX_RT_PRIO / 2 };
dev_info(&ctlr->dev,
"will run message pump with realtime priority\n");
sched_setscheduler(ctlr->kworker->task, SCHED_FIFO, &param);
sched_set_fifo(ctlr->kworker->task);
}
static int spi_init_queue(struct spi_controller *ctlr)

4
drivers/staging/android/ion/ion_heap.c
View file

@ -244,8 +244,6 @@ static int ion_heap_deferred_free(void *data)
int ion_heap_init_deferred_free(struct ion_heap *heap)
{
struct sched_param param = { .sched_priority = 0 };
INIT_LIST_HEAD(&heap->free_list);
init_waitqueue_head(&heap->waitqueue);
heap->task = kthread_run(ion_heap_deferred_free, heap,
@ -255,7 +253,7 @@ int ion_heap_init_deferred_free(struct ion_heap *heap)
__func__);
return PTR_ERR_OR_ZERO(heap->task);
}
sched_setscheduler(heap->task, SCHED_IDLE, &param);
sched_set_normal(heap->task, 19);
return 0;
}

5
drivers/thermal/intel/intel_powerclamp.c
View file

@ -70,9 +70,6 @@ static unsigned int control_cpu; /* The cpu assigned to collect stat and update
*/
static bool clamping;
static const struct sched_param sparam = {
.sched_priority = MAX_USER_RT_PRIO / 2,
};
struct powerclamp_worker_data {
struct kthread_worker *worker;
struct kthread_work balancing_work;
@ -488,7 +485,7 @@ static void start_power_clamp_worker(unsigned long cpu)
w_data->cpu = cpu;
w_data->clamping = true;
set_bit(cpu, cpu_clamping_mask);
sched_setscheduler(worker->task, SCHED_FIFO, &sparam);
sched_set_fifo(worker->task);
kthread_init_work(&w_data->balancing_work, clamp_balancing_func);
kthread_init_delayed_work(&w_data->idle_injection_work,
clamp_idle_injection_func);

3
drivers/tty/serial/sc16is7xx.c
View file

@ -1179,7 +1179,6 @@ static int sc16is7xx_probe(struct device *dev,
const struct sc16is7xx_devtype *devtype,
struct regmap *regmap, int irq)
{
struct sched_param sched_param = { .sched_priority = MAX_RT_PRIO / 2 };
unsigned long freq = 0, *pfreq = dev_get_platdata(dev);
unsigned int val;
u32 uartclk = 0;
@ -1239,7 +1238,7 @@ static int sc16is7xx_probe(struct device *dev,
ret = PTR_ERR(s->kworker_task);
goto out_clk;
}
sched_setscheduler(s->kworker_task, SCHED_FIFO, &sched_param);
sched_set_fifo(s->kworker_task);
#ifdef CONFIG_GPIOLIB
if (devtype->nr_gpio) {

3
drivers/watchdog/watchdog_dev.c
View file

@ -1144,14 +1144,13 @@ void watchdog_dev_unregister(struct watchdog_device *wdd)
int __init watchdog_dev_init(void)
{
int err;
struct sched_param param = {.sched_priority = MAX_RT_PRIO - 1,};
watchdog_kworker = kthread_create_worker(0, "watchdogd");
if (IS_ERR(watchdog_kworker)) {
pr_err("Failed to create watchdog kworker\n");
return PTR_ERR(watchdog_kworker);
}
sched_setscheduler(watchdog_kworker->task, SCHED_FIFO, &param);
sched_set_fifo(watchdog_kworker->task);
err = class_register(&watchdog_class);
if (err < 0) {

3
include/linux/sched.h
View file

@ -1648,6 +1648,9 @@ extern int idle_cpu(int cpu);
extern int available_idle_cpu(int cpu);
extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *);
extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *);
extern void sched_set_fifo(struct task_struct *p);
extern void sched_set_fifo_low(struct task_struct *p);
extern void sched_set_normal(struct task_struct *p, int nice);
extern int sched_setattr(struct task_struct *, const struct sched_attr *);
extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *);
extern struct task_struct *idle_task(int cpu);

6
kernel/irq/manage.c
View file

@ -1308,9 +1308,6 @@ static int
setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
{
struct task_struct *t;
struct sched_param param = {
.sched_priority = MAX_USER_RT_PRIO/2,
};
if (!secondary) {
t = kthread_create(irq_thread, new, "irq/%d-%s", irq,
@ -1318,13 +1315,12 @@ setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary)
} else {
t = kthread_create(irq_thread, new, "irq/%d-s-%s", irq,
new->name);
param.sched_priority -= 1;
}
if (IS_ERR(t))
return PTR_ERR(t);
sched_setscheduler_nocheck(t, SCHED_FIFO, &param);
sched_set_fifo(t);
/*
* We keep the reference to the task struct even if

10
kernel/locking/locktorture.c
View file

@ -436,8 +436,6 @@ static int torture_rtmutex_lock(void) __acquires(torture_rtmutex)
static void torture_rtmutex_boost(struct torture_random_state *trsp)
{
int policy;
struct sched_param param;
const unsigned int factor = 50000; /* yes, quite arbitrary */
if (!rt_task(current)) {
@ -448,8 +446,7 @@ static void torture_rtmutex_boost(struct torture_random_state *trsp)
*/
if (trsp && !(torture_random(trsp) %
(cxt.nrealwriters_stress * factor))) {
policy = SCHED_FIFO;
param.sched_priority = MAX_RT_PRIO - 1;
sched_set_fifo(current);
} else /* common case, do nothing */
return;
} else {
@ -462,13 +459,10 @@ static void torture_rtmutex_boost(struct torture_random_state *trsp)
*/
if (!trsp || !(torture_random(trsp) %
(cxt.nrealwriters_stress * factor * 2))) {
policy = SCHED_NORMAL;
param.sched_priority = 0;
sched_set_normal(current, 0);
} else /* common case, do nothing */
return;
}
sched_setscheduler_nocheck(current, policy, &param);
}
static void torture_rtmutex_delay(struct torture_random_state *trsp)

8
kernel/rcu/rcuperf.c
View file

@ -361,7 +361,6 @@ rcu_perf_writer(void *arg)
int i_max;
long me = (long)arg;
struct rcu_head *rhp = NULL;
struct sched_param sp;
bool started = false, done = false, alldone = false;
u64 t;
u64 *wdp;
@ -370,8 +369,7 @@ rcu_perf_writer(void *arg)
VERBOSE_PERFOUT_STRING("rcu_perf_writer task started");
WARN_ON(!wdpp);
set_cpus_allowed_ptr(current, cpumask_of(me % nr_cpu_ids));
sp.sched_priority = 1;
sched_setscheduler_nocheck(current, SCHED_FIFO, &sp);
sched_set_fifo_low(current);
if (holdoff)
schedule_timeout_uninterruptible(holdoff * HZ);
@ -427,9 +425,7 @@ retry:
started = true;
if (!done && i >= MIN_MEAS) {
done = true;
sp.sched_priority = 0;
sched_setscheduler_nocheck(current,
SCHED_NORMAL, &sp);
sched_set_normal(current, 0);
pr_alert("%s%s rcu_perf_writer %ld has %d measurements\n",
perf_type, PERF_FLAG, me, MIN_MEAS);
if (atomic_inc_return(&n_rcu_perf_writer_finished) >=

7
kernel/rcu/rcutorture.c
View file

@ -895,16 +895,11 @@ static int rcu_torture_boost(void *arg)
unsigned long endtime;
unsigned long oldstarttime;
struct rcu_boost_inflight rbi = { .inflight = 0 };
struct sched_param sp;
VERBOSE_TOROUT_STRING("rcu_torture_boost started");
/* Set real-time priority. */
sp.sched_priority = 1;
if (sched_setscheduler(current, SCHED_FIFO, &sp) < 0) {
VERBOSE_TOROUT_STRING("rcu_torture_boost RT prio failed!");
n_rcu_torture_boost_rterror++;
}
sched_set_fifo_low(current);
init_rcu_head_on_stack(&rbi.rcu);
/* Each pass through the following loop does one boost-test cycle. */

50
kernel/sched/core.c
View file

@ -5496,6 +5496,8 @@ static int _sched_setscheduler(struct task_struct *p, int policy,
* @policy: new policy.
* @param: structure containing the new RT priority.
*
* Use sched_set_fifo(), read its comment.
*
* Return: 0 on success. An error code otherwise.
*
* NOTE that the task may be already dead.
@ -5505,13 +5507,11 @@ int sched_setscheduler(struct task_struct *p, int policy,
{
return _sched_setscheduler(p, policy, param, true);
}
EXPORT_SYMBOL_GPL(sched_setscheduler);
int sched_setattr(struct task_struct *p, const struct sched_attr *attr)
{
return __sched_setscheduler(p, attr, true, true);
}
EXPORT_SYMBOL_GPL(sched_setattr);
int sched_setattr_nocheck(struct task_struct *p, const struct sched_attr *attr)
{
@ -5536,7 +5536,51 @@ int sched_setscheduler_nocheck(struct task_struct *p, int policy,
{
return _sched_setscheduler(p, policy, param, false);
}
EXPORT_SYMBOL_GPL(sched_setscheduler_nocheck);
/*
* SCHED_FIFO is a broken scheduler model; that is, it is fundamentally
* incapable of resource management, which is the one thing an OS really should
* be doing.
*
* This is of course the reason it is limited to privileged users only.
*
* Worse still; it is fundamentally impossible to compose static priority
* workloads. You cannot take two correctly working static prio workloads
* and smash them together and still expect them to work.
*
* For this reason 'all' FIFO tasks the kernel creates are basically at:
*
* MAX_RT_PRIO / 2
*
* The administrator _MUST_ configure the system, the kernel simply doesn't
* know enough information to make a sensible choice.
*/
void sched_set_fifo(struct task_struct *p)
{
struct sched_param sp = { .sched_priority = MAX_RT_PRIO / 2 };
WARN_ON_ONCE(sched_setscheduler_nocheck(p, SCHED_FIFO, &sp) != 0);
}
EXPORT_SYMBOL_GPL(sched_set_fifo);
/*
* For when you don't much care about FIFO, but want to be above SCHED_NORMAL.
*/
void sched_set_fifo_low(struct task_struct *p)
{
struct sched_param sp = { .sched_priority = 1 };
WARN_ON_ONCE(sched_setscheduler_nocheck(p, SCHED_FIFO, &sp) != 0);
}
EXPORT_SYMBOL_GPL(sched_set_fifo_low);
void sched_set_normal(struct task_struct *p, int nice)
{
struct sched_attr attr = {
.sched_policy = SCHED_NORMAL,
.sched_nice = nice,
};
WARN_ON_ONCE(sched_setattr_nocheck(p, &attr) != 0);
}
EXPORT_SYMBOL_GPL(sched_set_normal);
static int
do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param)

5
kernel/sched/psi.c
View file

@ -616,11 +616,8 @@ out:
static int psi_poll_worker(void *data)
{
struct psi_group *group = (struct psi_group *)data;
struct sched_param param = {
.sched_priority = 1,
};
sched_setscheduler_nocheck(current, SCHED_FIFO, &param);
sched_set_fifo_low(current);
while (true) {
wait_event_interruptible(group->poll_wait,

48
kernel/trace/ring_buffer_benchmark.c
View file

@ -45,8 +45,8 @@ MODULE_PARM_DESC(write_iteration, "# of writes between timestamp readings");
static int producer_nice = MAX_NICE;
static int consumer_nice = MAX_NICE;
static int producer_fifo = -1;
static int consumer_fifo = -1;
static int producer_fifo;
static int consumer_fifo;
module_param(producer_nice, int, 0644);
MODULE_PARM_DESC(producer_nice, "nice prio for producer");
@ -55,10 +55,10 @@ module_param(consumer_nice, int, 0644);
MODULE_PARM_DESC(consumer_nice, "nice prio for consumer");
module_param(producer_fifo, int, 0644);
MODULE_PARM_DESC(producer_fifo, "fifo prio for producer");
MODULE_PARM_DESC(producer_fifo, "use fifo for producer: 0 - disabled, 1 - low prio, 2 - fifo");
module_param(consumer_fifo, int, 0644);
MODULE_PARM_DESC(consumer_fifo, "fifo prio for consumer");
MODULE_PARM_DESC(consumer_fifo, "use fifo for consumer: 0 - disabled, 1 - low prio, 2 - fifo");
static int read_events;
@ -303,22 +303,22 @@ static void ring_buffer_producer(void)
trace_printk("ERROR!\n");
if (!disable_reader) {
if (consumer_fifo < 0)
if (consumer_fifo)
trace_printk("Running Consumer at SCHED_FIFO %s\n",
consumer_fifo == 1 ? "low" : "high");
else
trace_printk("Running Consumer at nice: %d\n",
consumer_nice);
else
trace_printk("Running Consumer at SCHED_FIFO %d\n",
consumer_fifo);
}
if (producer_fifo < 0)
if (producer_fifo)
trace_printk("Running Producer at SCHED_FIFO %s\n",
producer_fifo == 1 ? "low" : "high");
else
trace_printk("Running Producer at nice: %d\n",
producer_nice);
else
trace_printk("Running Producer at SCHED_FIFO %d\n",
producer_fifo);
/* Let the user know that the test is running at low priority */
if (producer_fifo < 0 && consumer_fifo < 0 &&
if (!producer_fifo && !consumer_fifo &&
producer_nice == MAX_NICE && consumer_nice == MAX_NICE)
trace_printk("WARNING!!! This test is running at lowest priority.\n");
@ -455,21 +455,19 @@ static int __init ring_buffer_benchmark_init(void)
* Run them as low-prio background tasks by default:
*/
if (!disable_reader) {
if (consumer_fifo >= 0) {
struct sched_param param = {
.sched_priority = consumer_fifo
};
sched_setscheduler(consumer, SCHED_FIFO, &param);
} else
if (consumer_fifo >= 2)
sched_set_fifo(consumer);
else if (consumer_fifo == 1)
sched_set_fifo_low(consumer);
else
set_user_nice(consumer, consumer_nice);
}
if (producer_fifo >= 0) {
struct sched_param param = {
.sched_priority = producer_fifo
};
sched_setscheduler(producer, SCHED_FIFO, &param);
} else
if (producer_fifo >= 2)
sched_set_fifo(producer);
else if (producer_fifo == 1)
sched_set_fifo_low(producer);
else
set_user_nice(producer, producer_nice);
return 0;