From 43ae34cb4cd650d1eb4460a8253a8e747ba052ac Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Mon, 9 Jul 2007 18:52:00 +0200 Subject: [PATCH] sched: scheduler debugging, core scheduler debugging core: implement /proc/sched_debug and /proc//sched files for scheduler debugging. Signed-off-by: Ingo Molnar --- fs/proc/base.c | 69 +++++++++++ include/linux/sched.h | 20 +++ kernel/sched_debug.c | 275 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 364 insertions(+) create mode 100644 kernel/sched_debug.c diff --git a/fs/proc/base.c b/fs/proc/base.c index 0f40e820c7fd..46ea5d56e1bb 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -929,6 +929,69 @@ static const struct file_operations proc_fault_inject_operations = { }; #endif +#ifdef CONFIG_SCHED_DEBUG +/* + * Print out various scheduling related per-task fields: + */ +static int sched_show(struct seq_file *m, void *v) +{ + struct inode *inode = m->private; + struct task_struct *p; + + WARN_ON(!inode); + + p = get_proc_task(inode); + if (!p) + return -ESRCH; + proc_sched_show_task(p, m); + + put_task_struct(p); + + return 0; +} + +static ssize_t +sched_write(struct file *file, const char __user *buf, + size_t count, loff_t *offset) +{ + struct inode *inode = file->f_path.dentry->d_inode; + struct task_struct *p; + + WARN_ON(!inode); + + p = get_proc_task(inode); + if (!p) + return -ESRCH; + proc_sched_set_task(p); + + put_task_struct(p); + + return count; +} + +static int sched_open(struct inode *inode, struct file *filp) +{ + int ret; + + ret = single_open(filp, sched_show, NULL); + if (!ret) { + struct seq_file *m = filp->private_data; + + m->private = inode; + } + return ret; +} + +static const struct file_operations proc_pid_sched_operations = { + .open = sched_open, + .read = seq_read, + .write = sched_write, + .llseek = seq_lseek, + .release = seq_release, +}; + +#endif + static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) { struct inode *inode = dentry->d_inode; @@ -1963,6 +2026,9 @@ static const struct pid_entry tgid_base_stuff[] = { INF("environ", S_IRUSR, pid_environ), INF("auxv", S_IRUSR, pid_auxv), INF("status", S_IRUGO, pid_status), +#ifdef CONFIG_SCHED_DEBUG + REG("sched", S_IRUGO|S_IWUSR, pid_sched), +#endif INF("cmdline", S_IRUGO, pid_cmdline), INF("stat", S_IRUGO, tgid_stat), INF("statm", S_IRUGO, pid_statm), @@ -2247,6 +2313,9 @@ static const struct pid_entry tid_base_stuff[] = { INF("environ", S_IRUSR, pid_environ), INF("auxv", S_IRUSR, pid_auxv), INF("status", S_IRUGO, pid_status), +#ifdef CONFIG_SCHED_DEBUG + REG("sched", S_IRUGO|S_IWUSR, pid_sched), +#endif INF("cmdline", S_IRUGO, pid_cmdline), INF("stat", S_IRUGO, tid_stat), INF("statm", S_IRUGO, pid_statm), diff --git a/include/linux/sched.h b/include/linux/sched.h index c9d65738bb7a..785ec8465bd3 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -132,6 +132,26 @@ extern unsigned long nr_active(void); extern unsigned long nr_iowait(void); extern unsigned long weighted_cpuload(const int cpu); +struct seq_file; +struct cfs_rq; +#ifdef CONFIG_SCHED_DEBUG +extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m); +extern void proc_sched_set_task(struct task_struct *p); +extern void +print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq, u64 now); +#else +static inline void +proc_sched_show_task(struct task_struct *p, struct seq_file *m) +{ +} +static inline void proc_sched_set_task(struct task_struct *p) +{ +} +static inline void +print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq, u64 now) +{ +} +#endif /* * Task state bitmask. NOTE! These bits are also diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c new file mode 100644 index 000000000000..1baf87cceb7c --- /dev/null +++ b/kernel/sched_debug.c @@ -0,0 +1,275 @@ +/* + * kernel/time/sched_debug.c + * + * Print the CFS rbtree + * + * Copyright(C) 2007, Red Hat, Inc., Ingo Molnar + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include +#include +#include +#include + +/* + * 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 \ + printk(x); \ + } while (0) + +static void +print_task(struct seq_file *m, struct rq *rq, struct task_struct *p, u64 now) +{ + if (rq->curr == p) + SEQ_printf(m, "R"); + else + SEQ_printf(m, " "); + + SEQ_printf(m, "%15s %5d %15Ld %13Ld %13Ld %9Ld %5d " + "%15Ld %15Ld %15Ld %15Ld %15Ld\n", + p->comm, p->pid, + (long long)p->se.fair_key, + (long long)(p->se.fair_key - rq->cfs.fair_clock), + (long long)p->se.wait_runtime, + (long long)(p->nvcsw + p->nivcsw), + p->prio, + (long long)p->se.sum_exec_runtime, + (long long)p->se.sum_wait_runtime, + (long long)p->se.sum_sleep_runtime, + (long long)p->se.wait_runtime_overruns, + (long long)p->se.wait_runtime_underruns); +} + +static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu, u64 now) +{ + struct task_struct *g, *p; + + SEQ_printf(m, + "\nrunnable tasks:\n" + " task PID tree-key delta waiting" + " switches prio" + " sum-exec sum-wait sum-sleep" + " wait-overrun wait-underrun\n" + "------------------------------------------------------------------" + "----------------" + "------------------------------------------------" + "--------------------------------\n"); + + read_lock_irq(&tasklist_lock); + + do_each_thread(g, p) { + if (!p->se.on_rq || task_cpu(p) != rq_cpu) + continue; + + print_task(m, rq, p, now); + } while_each_thread(g, p); + + read_unlock_irq(&tasklist_lock); +} + +static void +print_cfs_rq_runtime_sum(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) +{ + s64 wait_runtime_rq_sum = 0; + struct task_struct *p; + struct rb_node *curr; + unsigned long flags; + struct rq *rq = &per_cpu(runqueues, cpu); + + spin_lock_irqsave(&rq->lock, flags); + curr = first_fair(cfs_rq); + while (curr) { + p = rb_entry(curr, struct task_struct, se.run_node); + wait_runtime_rq_sum += p->se.wait_runtime; + + curr = rb_next(curr); + } + spin_unlock_irqrestore(&rq->lock, flags); + + SEQ_printf(m, " .%-30s: %Ld\n", "wait_runtime_rq_sum", + (long long)wait_runtime_rq_sum); +} + +void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq, u64 now) +{ + SEQ_printf(m, "\ncfs_rq %p\n", cfs_rq); + +#define P(x) \ + SEQ_printf(m, " .%-30s: %Ld\n", #x, (long long)(cfs_rq->x)) + + P(fair_clock); + P(exec_clock); + P(wait_runtime); + P(wait_runtime_overruns); + P(wait_runtime_underruns); + P(sleeper_bonus); +#undef P + + print_cfs_rq_runtime_sum(m, cpu, cfs_rq); +} + +static void print_cpu(struct seq_file *m, int cpu, u64 now) +{ + struct rq *rq = &per_cpu(runqueues, cpu); + +#ifdef CONFIG_X86 + { + unsigned int freq = cpu_khz ? : 1; + + SEQ_printf(m, "\ncpu#%d, %u.%03u MHz\n", + cpu, freq / 1000, (freq % 1000)); + } +#else + SEQ_printf(m, "\ncpu#%d\n", cpu); +#endif + +#define P(x) \ + SEQ_printf(m, " .%-30s: %Ld\n", #x, (long long)(rq->x)) + + P(nr_running); + SEQ_printf(m, " .%-30s: %lu\n", "load", + rq->ls.load.weight); + P(ls.delta_fair); + P(ls.delta_exec); + P(nr_switches); + P(nr_load_updates); + P(nr_uninterruptible); + SEQ_printf(m, " .%-30s: %lu\n", "jiffies", jiffies); + P(next_balance); + P(curr->pid); + P(clock); + P(prev_clock_raw); + P(clock_warps); + P(clock_overflows); + P(clock_unstable_events); + P(clock_max_delta); + P(cpu_load[0]); + P(cpu_load[1]); + P(cpu_load[2]); + P(cpu_load[3]); + P(cpu_load[4]); +#undef P + + print_cfs_stats(m, cpu, now); + + print_rq(m, rq, cpu, now); +} + +static int sched_debug_show(struct seq_file *m, void *v) +{ + u64 now = ktime_to_ns(ktime_get()); + int cpu; + + SEQ_printf(m, "Sched Debug Version: v0.04, cfs-v20, %s %.*s\n", + init_utsname()->release, + (int)strcspn(init_utsname()->version, " "), + init_utsname()->version); + + SEQ_printf(m, "now at %Lu nsecs\n", (unsigned long long)now); + + for_each_online_cpu(cpu) + print_cpu(m, cpu, now); + + SEQ_printf(m, "\n"); + + return 0; +} + +void sysrq_sched_debug_show(void) +{ + sched_debug_show(NULL, NULL); +} + +static int sched_debug_open(struct inode *inode, struct file *filp) +{ + return single_open(filp, sched_debug_show, NULL); +} + +static struct file_operations sched_debug_fops = { + .open = sched_debug_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +static int __init init_sched_debug_procfs(void) +{ + struct proc_dir_entry *pe; + + pe = create_proc_entry("sched_debug", 0644, NULL); + if (!pe) + return -ENOMEM; + + pe->proc_fops = &sched_debug_fops; + + return 0; +} + +__initcall(init_sched_debug_procfs); + +void proc_sched_show_task(struct task_struct *p, struct seq_file *m) +{ + unsigned long flags; + int num_threads = 1; + + rcu_read_lock(); + if (lock_task_sighand(p, &flags)) { + num_threads = atomic_read(&p->signal->count); + unlock_task_sighand(p, &flags); + } + rcu_read_unlock(); + + SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, p->pid, num_threads); + SEQ_printf(m, "----------------------------------------------\n"); +#define P(F) \ + SEQ_printf(m, "%-25s:%20Ld\n", #F, (long long)p->F) + + P(se.wait_start); + P(se.wait_start_fair); + P(se.exec_start); + P(se.sleep_start); + P(se.sleep_start_fair); + P(se.block_start); + P(se.sleep_max); + P(se.block_max); + P(se.exec_max); + P(se.wait_max); + P(se.wait_runtime); + P(se.wait_runtime_overruns); + P(se.wait_runtime_underruns); + P(se.sum_wait_runtime); + P(se.sum_exec_runtime); + SEQ_printf(m, "%-25s:%20Ld\n", + "nr_switches", (long long)(p->nvcsw + p->nivcsw)); + P(se.load.weight); + P(policy); + P(prio); +#undef P + + { + u64 t0, t1; + + t0 = sched_clock(); + t1 = sched_clock(); + SEQ_printf(m, "%-25s:%20Ld\n", + "clock-delta", (long long)(t1-t0)); + } +} + +void proc_sched_set_task(struct task_struct *p) +{ + p->se.sleep_max = p->se.block_max = p->se.exec_max = p->se.wait_max = 0; + p->se.wait_runtime_overruns = p->se.wait_runtime_underruns = 0; + p->se.sum_exec_runtime = 0; +} -- 2.39.5