linux-stable/kernel/sched/debug.c
Josh Don 304000390f sched: Cgroup SCHED_IDLE support
This extends SCHED_IDLE to cgroups.

Interface: cgroup/cpu.idle.
 0: default behavior
 1: SCHED_IDLE

Extending SCHED_IDLE to cgroups means that we incorporate the existing
aspects of SCHED_IDLE; a SCHED_IDLE cgroup will count all of its
descendant threads towards the idle_h_nr_running count of all of its
ancestor cgroups. Thus, sched_idle_rq() will work properly.
Additionally, SCHED_IDLE cgroups are configured with minimum weight.

There are two key differences between the per-task and per-cgroup
SCHED_IDLE interface:

  - The cgroup interface allows tasks within a SCHED_IDLE hierarchy to
    maintain their relative weights. The entity that is "idle" is the
    cgroup, not the tasks themselves.

  - Since the idle entity is the cgroup, our SCHED_IDLE wakeup preemption
    decision is not made by comparing the current task with the woken
    task, but rather by comparing their matching sched_entity.

A typical use-case for this is a user that creates an idle and a
non-idle subtree. The non-idle subtree will dominate competition vs
the idle subtree, but the idle subtree will still be high priority vs
other users on the system. The latter is accomplished via comparing
matching sched_entity in the waken preemption path (this could also be
improved by making the sched_idle_rq() decision dependent on the
perspective of a specific task).

For now, we maintain the existing SCHED_IDLE semantics. Future patches
may make improvements that extend how we treat SCHED_IDLE entities.

The per-task_group idle field is an integer that currently only holds
either a 0 or a 1. This is explicitly typed as an integer to allow for
further extensions to this API. For example, a negative value may
indicate a highly latency-sensitive cgroup that should be preferred
for preemption/placement/etc.

Signed-off-by: Josh Don <joshdon@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lore.kernel.org/r/20210730020019.1487127-2-joshdon@google.com
2021-08-20 12:32:58 +02:00

1069 lines
26 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* kernel/sched/debug.c
*
* Print the CFS rbtree and other debugging details
*
* Copyright(C) 2007, Red Hat, Inc., Ingo Molnar
*/
#include "sched.h"
/*
* This allows printing both to /proc/sched_debug and
* to the console
*/
#define SEQ_printf(m, x...) \
do { \
if (m) \
seq_printf(m, x); \
else \
pr_cont(x); \
} while (0)
/*
* Ease the printing of nsec fields:
*/
static long long nsec_high(unsigned long long nsec)
{
if ((long long)nsec < 0) {
nsec = -nsec;
do_div(nsec, 1000000);
return -nsec;
}
do_div(nsec, 1000000);
return nsec;
}
static unsigned long nsec_low(unsigned long long nsec)
{
if ((long long)nsec < 0)
nsec = -nsec;
return do_div(nsec, 1000000);
}
#define SPLIT_NS(x) nsec_high(x), nsec_low(x)
#define SCHED_FEAT(name, enabled) \
#name ,
static const char * const sched_feat_names[] = {
#include "features.h"
};
#undef SCHED_FEAT
static int sched_feat_show(struct seq_file *m, void *v)
{
int i;
for (i = 0; i < __SCHED_FEAT_NR; i++) {
if (!(sysctl_sched_features & (1UL << i)))
seq_puts(m, "NO_");
seq_printf(m, "%s ", sched_feat_names[i]);
}
seq_puts(m, "\n");
return 0;
}
#ifdef CONFIG_JUMP_LABEL
#define jump_label_key__true STATIC_KEY_INIT_TRUE
#define jump_label_key__false STATIC_KEY_INIT_FALSE
#define SCHED_FEAT(name, enabled) \
jump_label_key__##enabled ,
struct static_key sched_feat_keys[__SCHED_FEAT_NR] = {
#include "features.h"
};
#undef SCHED_FEAT
static void sched_feat_disable(int i)
{
static_key_disable_cpuslocked(&sched_feat_keys[i]);
}
static void sched_feat_enable(int i)
{
static_key_enable_cpuslocked(&sched_feat_keys[i]);
}
#else
static void sched_feat_disable(int i) { };
static void sched_feat_enable(int i) { };
#endif /* CONFIG_JUMP_LABEL */
static int sched_feat_set(char *cmp)
{
int i;
int neg = 0;
if (strncmp(cmp, "NO_", 3) == 0) {
neg = 1;
cmp += 3;
}
i = match_string(sched_feat_names, __SCHED_FEAT_NR, cmp);
if (i < 0)
return i;
if (neg) {
sysctl_sched_features &= ~(1UL << i);
sched_feat_disable(i);
} else {
sysctl_sched_features |= (1UL << i);
sched_feat_enable(i);
}
return 0;
}
static ssize_t
sched_feat_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
char buf[64];
char *cmp;
int ret;
struct inode *inode;
if (cnt > 63)
cnt = 63;
if (copy_from_user(&buf, ubuf, cnt))
return -EFAULT;
buf[cnt] = 0;
cmp = strstrip(buf);
/* Ensure the static_key remains in a consistent state */
inode = file_inode(filp);
cpus_read_lock();
inode_lock(inode);
ret = sched_feat_set(cmp);
inode_unlock(inode);
cpus_read_unlock();
if (ret < 0)
return ret;
*ppos += cnt;
return cnt;
}
static int sched_feat_open(struct inode *inode, struct file *filp)
{
return single_open(filp, sched_feat_show, NULL);
}
static const struct file_operations sched_feat_fops = {
.open = sched_feat_open,
.write = sched_feat_write,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
#ifdef CONFIG_SMP
static ssize_t sched_scaling_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
char buf[16];
if (cnt > 15)
cnt = 15;
if (copy_from_user(&buf, ubuf, cnt))
return -EFAULT;
if (kstrtouint(buf, 10, &sysctl_sched_tunable_scaling))
return -EINVAL;
if (sched_update_scaling())
return -EINVAL;
*ppos += cnt;
return cnt;
}
static int sched_scaling_show(struct seq_file *m, void *v)
{
seq_printf(m, "%d\n", sysctl_sched_tunable_scaling);
return 0;
}
static int sched_scaling_open(struct inode *inode, struct file *filp)
{
return single_open(filp, sched_scaling_show, NULL);
}
static const struct file_operations sched_scaling_fops = {
.open = sched_scaling_open,
.write = sched_scaling_write,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
#endif /* SMP */
#ifdef CONFIG_PREEMPT_DYNAMIC
static ssize_t sched_dynamic_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
char buf[16];
int mode;
if (cnt > 15)
cnt = 15;
if (copy_from_user(&buf, ubuf, cnt))
return -EFAULT;
buf[cnt] = 0;
mode = sched_dynamic_mode(strstrip(buf));
if (mode < 0)
return mode;
sched_dynamic_update(mode);
*ppos += cnt;
return cnt;
}
static int sched_dynamic_show(struct seq_file *m, void *v)
{
static const char * preempt_modes[] = {
"none", "voluntary", "full"
};
int i;
for (i = 0; i < ARRAY_SIZE(preempt_modes); i++) {
if (preempt_dynamic_mode == i)
seq_puts(m, "(");
seq_puts(m, preempt_modes[i]);
if (preempt_dynamic_mode == i)
seq_puts(m, ")");
seq_puts(m, " ");
}
seq_puts(m, "\n");
return 0;
}
static int sched_dynamic_open(struct inode *inode, struct file *filp)
{
return single_open(filp, sched_dynamic_show, NULL);
}
static const struct file_operations sched_dynamic_fops = {
.open = sched_dynamic_open,
.write = sched_dynamic_write,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
#endif /* CONFIG_PREEMPT_DYNAMIC */
__read_mostly bool sched_debug_verbose;
static const struct seq_operations sched_debug_sops;
static int sched_debug_open(struct inode *inode, struct file *filp)
{
return seq_open(filp, &sched_debug_sops);
}
static const struct file_operations sched_debug_fops = {
.open = sched_debug_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
static struct dentry *debugfs_sched;
static __init int sched_init_debug(void)
{
struct dentry __maybe_unused *numa;
debugfs_sched = debugfs_create_dir("sched", NULL);
debugfs_create_file("features", 0644, debugfs_sched, NULL, &sched_feat_fops);
debugfs_create_bool("verbose", 0644, debugfs_sched, &sched_debug_verbose);
#ifdef CONFIG_PREEMPT_DYNAMIC
debugfs_create_file("preempt", 0644, debugfs_sched, NULL, &sched_dynamic_fops);
#endif
debugfs_create_u32("latency_ns", 0644, debugfs_sched, &sysctl_sched_latency);
debugfs_create_u32("min_granularity_ns", 0644, debugfs_sched, &sysctl_sched_min_granularity);
debugfs_create_u32("wakeup_granularity_ns", 0644, debugfs_sched, &sysctl_sched_wakeup_granularity);
debugfs_create_u32("latency_warn_ms", 0644, debugfs_sched, &sysctl_resched_latency_warn_ms);
debugfs_create_u32("latency_warn_once", 0644, debugfs_sched, &sysctl_resched_latency_warn_once);
#ifdef CONFIG_SMP
debugfs_create_file("tunable_scaling", 0644, debugfs_sched, NULL, &sched_scaling_fops);
debugfs_create_u32("migration_cost_ns", 0644, debugfs_sched, &sysctl_sched_migration_cost);
debugfs_create_u32("nr_migrate", 0644, debugfs_sched, &sysctl_sched_nr_migrate);
mutex_lock(&sched_domains_mutex);
update_sched_domain_debugfs();
mutex_unlock(&sched_domains_mutex);
#endif
#ifdef CONFIG_NUMA_BALANCING
numa = debugfs_create_dir("numa_balancing", debugfs_sched);
debugfs_create_u32("scan_delay_ms", 0644, numa, &sysctl_numa_balancing_scan_delay);
debugfs_create_u32("scan_period_min_ms", 0644, numa, &sysctl_numa_balancing_scan_period_min);
debugfs_create_u32("scan_period_max_ms", 0644, numa, &sysctl_numa_balancing_scan_period_max);
debugfs_create_u32("scan_size_mb", 0644, numa, &sysctl_numa_balancing_scan_size);
#endif
debugfs_create_file("debug", 0444, debugfs_sched, NULL, &sched_debug_fops);
return 0;
}
late_initcall(sched_init_debug);
#ifdef CONFIG_SMP
static cpumask_var_t sd_sysctl_cpus;
static struct dentry *sd_dentry;
static int sd_flags_show(struct seq_file *m, void *v)
{
unsigned long flags = *(unsigned int *)m->private;
int idx;
for_each_set_bit(idx, &flags, __SD_FLAG_CNT) {
seq_puts(m, sd_flag_debug[idx].name);
seq_puts(m, " ");
}
seq_puts(m, "\n");
return 0;
}
static int sd_flags_open(struct inode *inode, struct file *file)
{
return single_open(file, sd_flags_show, inode->i_private);
}
static const struct file_operations sd_flags_fops = {
.open = sd_flags_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static void register_sd(struct sched_domain *sd, struct dentry *parent)
{
#define SDM(type, mode, member) \
debugfs_create_##type(#member, mode, parent, &sd->member)
SDM(ulong, 0644, min_interval);
SDM(ulong, 0644, max_interval);
SDM(u64, 0644, max_newidle_lb_cost);
SDM(u32, 0644, busy_factor);
SDM(u32, 0644, imbalance_pct);
SDM(u32, 0644, cache_nice_tries);
SDM(str, 0444, name);
#undef SDM
debugfs_create_file("flags", 0444, parent, &sd->flags, &sd_flags_fops);
}
void update_sched_domain_debugfs(void)
{
int cpu, i;
/*
* This can unfortunately be invoked before sched_debug_init() creates
* the debug directory. Don't touch sd_sysctl_cpus until then.
*/
if (!debugfs_sched)
return;
if (!cpumask_available(sd_sysctl_cpus)) {
if (!alloc_cpumask_var(&sd_sysctl_cpus, GFP_KERNEL))
return;
cpumask_copy(sd_sysctl_cpus, cpu_possible_mask);
}
if (!sd_dentry)
sd_dentry = debugfs_create_dir("domains", debugfs_sched);
for_each_cpu(cpu, sd_sysctl_cpus) {
struct sched_domain *sd;
struct dentry *d_cpu;
char buf[32];
snprintf(buf, sizeof(buf), "cpu%d", cpu);
debugfs_remove(debugfs_lookup(buf, sd_dentry));
d_cpu = debugfs_create_dir(buf, sd_dentry);
i = 0;
for_each_domain(cpu, sd) {
struct dentry *d_sd;
snprintf(buf, sizeof(buf), "domain%d", i);
d_sd = debugfs_create_dir(buf, d_cpu);
register_sd(sd, d_sd);
i++;
}
__cpumask_clear_cpu(cpu, sd_sysctl_cpus);
}
}
void dirty_sched_domain_sysctl(int cpu)
{
if (cpumask_available(sd_sysctl_cpus))
__cpumask_set_cpu(cpu, sd_sysctl_cpus);
}
#endif /* CONFIG_SMP */
#ifdef CONFIG_FAIR_GROUP_SCHED
static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group *tg)
{
struct sched_entity *se = tg->se[cpu];
#define P(F) SEQ_printf(m, " .%-30s: %lld\n", #F, (long long)F)
#define P_SCHEDSTAT(F) SEQ_printf(m, " .%-30s: %lld\n", #F, (long long)schedstat_val(F))
#define PN(F) SEQ_printf(m, " .%-30s: %lld.%06ld\n", #F, SPLIT_NS((long long)F))
#define PN_SCHEDSTAT(F) SEQ_printf(m, " .%-30s: %lld.%06ld\n", #F, SPLIT_NS((long long)schedstat_val(F)))
if (!se)
return;
PN(se->exec_start);
PN(se->vruntime);
PN(se->sum_exec_runtime);
if (schedstat_enabled()) {
PN_SCHEDSTAT(se->statistics.wait_start);
PN_SCHEDSTAT(se->statistics.sleep_start);
PN_SCHEDSTAT(se->statistics.block_start);
PN_SCHEDSTAT(se->statistics.sleep_max);
PN_SCHEDSTAT(se->statistics.block_max);
PN_SCHEDSTAT(se->statistics.exec_max);
PN_SCHEDSTAT(se->statistics.slice_max);
PN_SCHEDSTAT(se->statistics.wait_max);
PN_SCHEDSTAT(se->statistics.wait_sum);
P_SCHEDSTAT(se->statistics.wait_count);
}
P(se->load.weight);
#ifdef CONFIG_SMP
P(se->avg.load_avg);
P(se->avg.util_avg);
P(se->avg.runnable_avg);
#endif
#undef PN_SCHEDSTAT
#undef PN
#undef P_SCHEDSTAT
#undef P
}
#endif
#ifdef CONFIG_CGROUP_SCHED
static DEFINE_SPINLOCK(sched_debug_lock);
static char group_path[PATH_MAX];
static void task_group_path(struct task_group *tg, char *path, int plen)
{
if (autogroup_path(tg, path, plen))
return;
cgroup_path(tg->css.cgroup, path, plen);
}
/*
* Only 1 SEQ_printf_task_group_path() caller can use the full length
* group_path[] for cgroup path. Other simultaneous callers will have
* to use a shorter stack buffer. A "..." suffix is appended at the end
* of the stack buffer so that it will show up in case the output length
* matches the given buffer size to indicate possible path name truncation.
*/
#define SEQ_printf_task_group_path(m, tg, fmt...) \
{ \
if (spin_trylock(&sched_debug_lock)) { \
task_group_path(tg, group_path, sizeof(group_path)); \
SEQ_printf(m, fmt, group_path); \
spin_unlock(&sched_debug_lock); \
} else { \
char buf[128]; \
char *bufend = buf + sizeof(buf) - 3; \
task_group_path(tg, buf, bufend - buf); \
strcpy(bufend - 1, "..."); \
SEQ_printf(m, fmt, buf); \
} \
}
#endif
static void
print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
{
if (task_current(rq, p))
SEQ_printf(m, ">R");
else
SEQ_printf(m, " %c", task_state_to_char(p));
SEQ_printf(m, " %15s %5d %9Ld.%06ld %9Ld %5d ",
p->comm, task_pid_nr(p),
SPLIT_NS(p->se.vruntime),
(long long)(p->nvcsw + p->nivcsw),
p->prio);
SEQ_printf(m, "%9Ld.%06ld %9Ld.%06ld %9Ld.%06ld",
SPLIT_NS(schedstat_val_or_zero(p->se.statistics.wait_sum)),
SPLIT_NS(p->se.sum_exec_runtime),
SPLIT_NS(schedstat_val_or_zero(p->se.statistics.sum_sleep_runtime)));
#ifdef CONFIG_NUMA_BALANCING
SEQ_printf(m, " %d %d", task_node(p), task_numa_group_id(p));
#endif
#ifdef CONFIG_CGROUP_SCHED
SEQ_printf_task_group_path(m, task_group(p), " %s")
#endif
SEQ_printf(m, "\n");
}
static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
{
struct task_struct *g, *p;
SEQ_printf(m, "\n");
SEQ_printf(m, "runnable tasks:\n");
SEQ_printf(m, " S task PID tree-key switches prio"
" wait-time sum-exec sum-sleep\n");
SEQ_printf(m, "-------------------------------------------------------"
"------------------------------------------------------\n");
rcu_read_lock();
for_each_process_thread(g, p) {
if (task_cpu(p) != rq_cpu)
continue;
print_task(m, rq, p);
}
rcu_read_unlock();
}
void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
{
s64 MIN_vruntime = -1, min_vruntime, max_vruntime = -1,
spread, rq0_min_vruntime, spread0;
struct rq *rq = cpu_rq(cpu);
struct sched_entity *last;
unsigned long flags;
#ifdef CONFIG_FAIR_GROUP_SCHED
SEQ_printf(m, "\n");
SEQ_printf_task_group_path(m, cfs_rq->tg, "cfs_rq[%d]:%s\n", cpu);
#else
SEQ_printf(m, "\n");
SEQ_printf(m, "cfs_rq[%d]:\n", cpu);
#endif
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "exec_clock",
SPLIT_NS(cfs_rq->exec_clock));
raw_spin_rq_lock_irqsave(rq, flags);
if (rb_first_cached(&cfs_rq->tasks_timeline))
MIN_vruntime = (__pick_first_entity(cfs_rq))->vruntime;
last = __pick_last_entity(cfs_rq);
if (last)
max_vruntime = last->vruntime;
min_vruntime = cfs_rq->min_vruntime;
rq0_min_vruntime = cpu_rq(0)->cfs.min_vruntime;
raw_spin_rq_unlock_irqrestore(rq, flags);
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "MIN_vruntime",
SPLIT_NS(MIN_vruntime));
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "min_vruntime",
SPLIT_NS(min_vruntime));
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "max_vruntime",
SPLIT_NS(max_vruntime));
spread = max_vruntime - MIN_vruntime;
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "spread",
SPLIT_NS(spread));
spread0 = min_vruntime - rq0_min_vruntime;
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "spread0",
SPLIT_NS(spread0));
SEQ_printf(m, " .%-30s: %d\n", "nr_spread_over",
cfs_rq->nr_spread_over);
SEQ_printf(m, " .%-30s: %d\n", "nr_running", cfs_rq->nr_running);
SEQ_printf(m, " .%-30s: %d\n", "h_nr_running", cfs_rq->h_nr_running);
SEQ_printf(m, " .%-30s: %d\n", "idle_h_nr_running",
cfs_rq->idle_h_nr_running);
SEQ_printf(m, " .%-30s: %ld\n", "load", cfs_rq->load.weight);
#ifdef CONFIG_SMP
SEQ_printf(m, " .%-30s: %lu\n", "load_avg",
cfs_rq->avg.load_avg);
SEQ_printf(m, " .%-30s: %lu\n", "runnable_avg",
cfs_rq->avg.runnable_avg);
SEQ_printf(m, " .%-30s: %lu\n", "util_avg",
cfs_rq->avg.util_avg);
SEQ_printf(m, " .%-30s: %u\n", "util_est_enqueued",
cfs_rq->avg.util_est.enqueued);
SEQ_printf(m, " .%-30s: %ld\n", "removed.load_avg",
cfs_rq->removed.load_avg);
SEQ_printf(m, " .%-30s: %ld\n", "removed.util_avg",
cfs_rq->removed.util_avg);
SEQ_printf(m, " .%-30s: %ld\n", "removed.runnable_avg",
cfs_rq->removed.runnable_avg);
#ifdef CONFIG_FAIR_GROUP_SCHED
SEQ_printf(m, " .%-30s: %lu\n", "tg_load_avg_contrib",
cfs_rq->tg_load_avg_contrib);
SEQ_printf(m, " .%-30s: %ld\n", "tg_load_avg",
atomic_long_read(&cfs_rq->tg->load_avg));
#endif
#endif
#ifdef CONFIG_CFS_BANDWIDTH
SEQ_printf(m, " .%-30s: %d\n", "throttled",
cfs_rq->throttled);
SEQ_printf(m, " .%-30s: %d\n", "throttle_count",
cfs_rq->throttle_count);
#endif
#ifdef CONFIG_FAIR_GROUP_SCHED
print_cfs_group_stats(m, cpu, cfs_rq->tg);
#endif
}
void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
{
#ifdef CONFIG_RT_GROUP_SCHED
SEQ_printf(m, "\n");
SEQ_printf_task_group_path(m, rt_rq->tg, "rt_rq[%d]:%s\n", cpu);
#else
SEQ_printf(m, "\n");
SEQ_printf(m, "rt_rq[%d]:\n", cpu);
#endif
#define P(x) \
SEQ_printf(m, " .%-30s: %Ld\n", #x, (long long)(rt_rq->x))
#define PU(x) \
SEQ_printf(m, " .%-30s: %lu\n", #x, (unsigned long)(rt_rq->x))
#define PN(x) \
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rt_rq->x))
PU(rt_nr_running);
#ifdef CONFIG_SMP
PU(rt_nr_migratory);
#endif
P(rt_throttled);
PN(rt_time);
PN(rt_runtime);
#undef PN
#undef PU
#undef P
}
void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq)
{
struct dl_bw *dl_bw;
SEQ_printf(m, "\n");
SEQ_printf(m, "dl_rq[%d]:\n", cpu);
#define PU(x) \
SEQ_printf(m, " .%-30s: %lu\n", #x, (unsigned long)(dl_rq->x))
PU(dl_nr_running);
#ifdef CONFIG_SMP
PU(dl_nr_migratory);
dl_bw = &cpu_rq(cpu)->rd->dl_bw;
#else
dl_bw = &dl_rq->dl_bw;
#endif
SEQ_printf(m, " .%-30s: %lld\n", "dl_bw->bw", dl_bw->bw);
SEQ_printf(m, " .%-30s: %lld\n", "dl_bw->total_bw", dl_bw->total_bw);
#undef PU
}
static void print_cpu(struct seq_file *m, int cpu)
{
struct rq *rq = cpu_rq(cpu);
#ifdef CONFIG_X86
{
unsigned int freq = cpu_khz ? : 1;
SEQ_printf(m, "cpu#%d, %u.%03u MHz\n",
cpu, freq / 1000, (freq % 1000));
}
#else
SEQ_printf(m, "cpu#%d\n", cpu);
#endif
#define P(x) \
do { \
if (sizeof(rq->x) == 4) \
SEQ_printf(m, " .%-30s: %ld\n", #x, (long)(rq->x)); \
else \
SEQ_printf(m, " .%-30s: %Ld\n", #x, (long long)(rq->x));\
} while (0)
#define PN(x) \
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rq->x))
P(nr_running);
P(nr_switches);
P(nr_uninterruptible);
PN(next_balance);
SEQ_printf(m, " .%-30s: %ld\n", "curr->pid", (long)(task_pid_nr(rq->curr)));
PN(clock);
PN(clock_task);
#undef P
#undef PN
#ifdef CONFIG_SMP
#define P64(n) SEQ_printf(m, " .%-30s: %Ld\n", #n, rq->n);
P64(avg_idle);
P64(max_idle_balance_cost);
#undef P64
#endif
#define P(n) SEQ_printf(m, " .%-30s: %d\n", #n, schedstat_val(rq->n));
if (schedstat_enabled()) {
P(yld_count);
P(sched_count);
P(sched_goidle);
P(ttwu_count);
P(ttwu_local);
}
#undef P
print_cfs_stats(m, cpu);
print_rt_stats(m, cpu);
print_dl_stats(m, cpu);
print_rq(m, rq, cpu);
SEQ_printf(m, "\n");
}
static const char *sched_tunable_scaling_names[] = {
"none",
"logarithmic",
"linear"
};
static void sched_debug_header(struct seq_file *m)
{
u64 ktime, sched_clk, cpu_clk;
unsigned long flags;
local_irq_save(flags);
ktime = ktime_to_ns(ktime_get());
sched_clk = sched_clock();
cpu_clk = local_clock();
local_irq_restore(flags);
SEQ_printf(m, "Sched Debug Version: v0.11, %s %.*s\n",
init_utsname()->release,
(int)strcspn(init_utsname()->version, " "),
init_utsname()->version);
#define P(x) \
SEQ_printf(m, "%-40s: %Ld\n", #x, (long long)(x))
#define PN(x) \
SEQ_printf(m, "%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
PN(ktime);
PN(sched_clk);
PN(cpu_clk);
P(jiffies);
#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
P(sched_clock_stable());
#endif
#undef PN
#undef P
SEQ_printf(m, "\n");
SEQ_printf(m, "sysctl_sched\n");
#define P(x) \
SEQ_printf(m, " .%-40s: %Ld\n", #x, (long long)(x))
#define PN(x) \
SEQ_printf(m, " .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
PN(sysctl_sched_latency);
PN(sysctl_sched_min_granularity);
PN(sysctl_sched_wakeup_granularity);
P(sysctl_sched_child_runs_first);
P(sysctl_sched_features);
#undef PN
#undef P
SEQ_printf(m, " .%-40s: %d (%s)\n",
"sysctl_sched_tunable_scaling",
sysctl_sched_tunable_scaling,
sched_tunable_scaling_names[sysctl_sched_tunable_scaling]);
SEQ_printf(m, "\n");
}
static int sched_debug_show(struct seq_file *m, void *v)
{
int cpu = (unsigned long)(v - 2);
if (cpu != -1)
print_cpu(m, cpu);
else
sched_debug_header(m);
return 0;
}
void sysrq_sched_debug_show(void)
{
int cpu;
sched_debug_header(NULL);
for_each_online_cpu(cpu) {
/*
* Need to reset softlockup watchdogs on all CPUs, because
* another CPU might be blocked waiting for us to process
* an IPI or stop_machine.
*/
touch_nmi_watchdog();
touch_all_softlockup_watchdogs();
print_cpu(NULL, cpu);
}
}
/*
* This iterator needs some explanation.
* It returns 1 for the header position.
* This means 2 is CPU 0.
* In a hotplugged system some CPUs, including CPU 0, may be missing so we have
* to use cpumask_* to iterate over the CPUs.
*/
static void *sched_debug_start(struct seq_file *file, loff_t *offset)
{
unsigned long n = *offset;
if (n == 0)
return (void *) 1;
n--;
if (n > 0)
n = cpumask_next(n - 1, cpu_online_mask);
else
n = cpumask_first(cpu_online_mask);
*offset = n + 1;
if (n < nr_cpu_ids)
return (void *)(unsigned long)(n + 2);
return NULL;
}
static void *sched_debug_next(struct seq_file *file, void *data, loff_t *offset)
{
(*offset)++;
return sched_debug_start(file, offset);
}
static void sched_debug_stop(struct seq_file *file, void *data)
{
}
static const struct seq_operations sched_debug_sops = {
.start = sched_debug_start,
.next = sched_debug_next,
.stop = sched_debug_stop,
.show = sched_debug_show,
};
#define __PS(S, F) SEQ_printf(m, "%-45s:%21Ld\n", S, (long long)(F))
#define __P(F) __PS(#F, F)
#define P(F) __PS(#F, p->F)
#define PM(F, M) __PS(#F, p->F & (M))
#define __PSN(S, F) SEQ_printf(m, "%-45s:%14Ld.%06ld\n", S, SPLIT_NS((long long)(F)))
#define __PN(F) __PSN(#F, F)
#define PN(F) __PSN(#F, p->F)
#ifdef CONFIG_NUMA_BALANCING
void print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
unsigned long tpf, unsigned long gsf, unsigned long gpf)
{
SEQ_printf(m, "numa_faults node=%d ", node);
SEQ_printf(m, "task_private=%lu task_shared=%lu ", tpf, tsf);
SEQ_printf(m, "group_private=%lu group_shared=%lu\n", gpf, gsf);
}
#endif
static void sched_show_numa(struct task_struct *p, struct seq_file *m)
{
#ifdef CONFIG_NUMA_BALANCING
struct mempolicy *pol;
if (p->mm)
P(mm->numa_scan_seq);
task_lock(p);
pol = p->mempolicy;
if (pol && !(pol->flags & MPOL_F_MORON))
pol = NULL;
mpol_get(pol);
task_unlock(p);
P(numa_pages_migrated);
P(numa_preferred_nid);
P(total_numa_faults);
SEQ_printf(m, "current_node=%d, numa_group_id=%d\n",
task_node(p), task_numa_group_id(p));
show_numa_stats(p, m);
mpol_put(pol);
#endif
}
void proc_sched_show_task(struct task_struct *p, struct pid_namespace *ns,
struct seq_file *m)
{
unsigned long nr_switches;
SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, task_pid_nr_ns(p, ns),
get_nr_threads(p));
SEQ_printf(m,
"---------------------------------------------------------"
"----------\n");
#define P_SCHEDSTAT(F) __PS(#F, schedstat_val(p->F))
#define PN_SCHEDSTAT(F) __PSN(#F, schedstat_val(p->F))
PN(se.exec_start);
PN(se.vruntime);
PN(se.sum_exec_runtime);
nr_switches = p->nvcsw + p->nivcsw;
P(se.nr_migrations);
if (schedstat_enabled()) {
u64 avg_atom, avg_per_cpu;
PN_SCHEDSTAT(se.statistics.sum_sleep_runtime);
PN_SCHEDSTAT(se.statistics.wait_start);
PN_SCHEDSTAT(se.statistics.sleep_start);
PN_SCHEDSTAT(se.statistics.block_start);
PN_SCHEDSTAT(se.statistics.sleep_max);
PN_SCHEDSTAT(se.statistics.block_max);
PN_SCHEDSTAT(se.statistics.exec_max);
PN_SCHEDSTAT(se.statistics.slice_max);
PN_SCHEDSTAT(se.statistics.wait_max);
PN_SCHEDSTAT(se.statistics.wait_sum);
P_SCHEDSTAT(se.statistics.wait_count);
PN_SCHEDSTAT(se.statistics.iowait_sum);
P_SCHEDSTAT(se.statistics.iowait_count);
P_SCHEDSTAT(se.statistics.nr_migrations_cold);
P_SCHEDSTAT(se.statistics.nr_failed_migrations_affine);
P_SCHEDSTAT(se.statistics.nr_failed_migrations_running);
P_SCHEDSTAT(se.statistics.nr_failed_migrations_hot);
P_SCHEDSTAT(se.statistics.nr_forced_migrations);
P_SCHEDSTAT(se.statistics.nr_wakeups);
P_SCHEDSTAT(se.statistics.nr_wakeups_sync);
P_SCHEDSTAT(se.statistics.nr_wakeups_migrate);
P_SCHEDSTAT(se.statistics.nr_wakeups_local);
P_SCHEDSTAT(se.statistics.nr_wakeups_remote);
P_SCHEDSTAT(se.statistics.nr_wakeups_affine);
P_SCHEDSTAT(se.statistics.nr_wakeups_affine_attempts);
P_SCHEDSTAT(se.statistics.nr_wakeups_passive);
P_SCHEDSTAT(se.statistics.nr_wakeups_idle);
avg_atom = p->se.sum_exec_runtime;
if (nr_switches)
avg_atom = div64_ul(avg_atom, nr_switches);
else
avg_atom = -1LL;
avg_per_cpu = p->se.sum_exec_runtime;
if (p->se.nr_migrations) {
avg_per_cpu = div64_u64(avg_per_cpu,
p->se.nr_migrations);
} else {
avg_per_cpu = -1LL;
}
__PN(avg_atom);
__PN(avg_per_cpu);
}
__P(nr_switches);
__PS("nr_voluntary_switches", p->nvcsw);
__PS("nr_involuntary_switches", p->nivcsw);
P(se.load.weight);
#ifdef CONFIG_SMP
P(se.avg.load_sum);
P(se.avg.runnable_sum);
P(se.avg.util_sum);
P(se.avg.load_avg);
P(se.avg.runnable_avg);
P(se.avg.util_avg);
P(se.avg.last_update_time);
P(se.avg.util_est.ewma);
PM(se.avg.util_est.enqueued, ~UTIL_AVG_UNCHANGED);
#endif
#ifdef CONFIG_UCLAMP_TASK
__PS("uclamp.min", p->uclamp_req[UCLAMP_MIN].value);
__PS("uclamp.max", p->uclamp_req[UCLAMP_MAX].value);
__PS("effective uclamp.min", uclamp_eff_value(p, UCLAMP_MIN));
__PS("effective uclamp.max", uclamp_eff_value(p, UCLAMP_MAX));
#endif
P(policy);
P(prio);
if (task_has_dl_policy(p)) {
P(dl.runtime);
P(dl.deadline);
}
#undef PN_SCHEDSTAT
#undef P_SCHEDSTAT
{
unsigned int this_cpu = raw_smp_processor_id();
u64 t0, t1;
t0 = cpu_clock(this_cpu);
t1 = cpu_clock(this_cpu);
__PS("clock-delta", t1-t0);
}
sched_show_numa(p, m);
}
void proc_sched_set_task(struct task_struct *p)
{
#ifdef CONFIG_SCHEDSTATS
memset(&p->se.statistics, 0, sizeof(p->se.statistics));
#endif
}
void resched_latency_warn(int cpu, u64 latency)
{
static DEFINE_RATELIMIT_STATE(latency_check_ratelimit, 60 * 60 * HZ, 1);
WARN(__ratelimit(&latency_check_ratelimit),
"sched: CPU %d need_resched set for > %llu ns (%d ticks) "
"without schedule\n",
cpu, latency, cpu_rq(cpu)->ticks_without_resched);
}