sched: latencytop support

LatencyTOP kernel infrastructure; it measures latencies in the
scheduler and tracks it system wide and per process.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Arjan van de Ven
2008-01-25 21:08:34 +01:00
committed by Ingo Molnar
parent 326587b840
commit 9745512ce7
11 changed files with 429 additions and 1 deletions

View File

@@ -310,6 +310,77 @@ static int proc_pid_schedstat(struct task_struct *task, char *buffer)
}
#endif
#ifdef CONFIG_LATENCYTOP
static int lstats_show_proc(struct seq_file *m, void *v)
{
int i;
struct task_struct *task = m->private;
seq_puts(m, "Latency Top version : v0.1\n");
for (i = 0; i < 32; i++) {
if (task->latency_record[i].backtrace[0]) {
int q;
seq_printf(m, "%i %li %li ",
task->latency_record[i].count,
task->latency_record[i].time,
task->latency_record[i].max);
for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
char sym[KSYM_NAME_LEN];
char *c;
if (!task->latency_record[i].backtrace[q])
break;
if (task->latency_record[i].backtrace[q] == ULONG_MAX)
break;
sprint_symbol(sym, task->latency_record[i].backtrace[q]);
c = strchr(sym, '+');
if (c)
*c = 0;
seq_printf(m, "%s ", sym);
}
seq_printf(m, "\n");
}
}
return 0;
}
static int lstats_open(struct inode *inode, struct file *file)
{
int ret;
struct seq_file *m;
struct task_struct *task = get_proc_task(inode);
ret = single_open(file, lstats_show_proc, NULL);
if (!ret) {
m = file->private_data;
m->private = task;
}
return ret;
}
static ssize_t lstats_write(struct file *file, const char __user *buf,
size_t count, loff_t *offs)
{
struct seq_file *m;
struct task_struct *task;
m = file->private_data;
task = m->private;
clear_all_latency_tracing(task);
return count;
}
static const struct file_operations proc_lstats_operations = {
.open = lstats_open,
.read = seq_read,
.write = lstats_write,
.llseek = seq_lseek,
.release = single_release,
};
#endif
/* The badness from the OOM killer */
unsigned long badness(struct task_struct *p, unsigned long uptime);
static int proc_oom_score(struct task_struct *task, char *buffer)
@@ -1020,6 +1091,7 @@ static const struct file_operations proc_fault_inject_operations = {
};
#endif
#ifdef CONFIG_SCHED_DEBUG
/*
* Print out various scheduling related per-task fields:
@@ -2230,6 +2302,9 @@ static const struct pid_entry tgid_base_stuff[] = {
#ifdef CONFIG_SCHEDSTATS
INF("schedstat", S_IRUGO, pid_schedstat),
#endif
#ifdef CONFIG_LATENCYTOP
REG("latency", S_IRUGO, lstats),
#endif
#ifdef CONFIG_PROC_PID_CPUSET
REG("cpuset", S_IRUGO, cpuset),
#endif
@@ -2555,6 +2630,9 @@ static const struct pid_entry tid_base_stuff[] = {
#ifdef CONFIG_SCHEDSTATS
INF("schedstat", S_IRUGO, pid_schedstat),
#endif
#ifdef CONFIG_LATENCYTOP
REG("latency", S_IRUGO, lstats),
#endif
#ifdef CONFIG_PROC_PID_CPUSET
REG("cpuset", S_IRUGO, cpuset),
#endif