blob: 2ece399f2862361aaa0789f08a49a4bae169043e [file] [log] [blame]
/*
* Copyright (C) 2007 IBM Deutschland Entwicklung GmbH
* Released under GPL v2.
*
* Partially based on net/ipv4/tcp_probe.c.
*
* Simple tracing facility for spu contexts.
*/
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/marker.h>
#include <linux/proc_fs.h>
#include <linux/wait.h>
#include <asm/atomic.h>
#include <asm/uaccess.h>
#include "spufs.h"
struct spu_probe {
const char *name;
const char *format;
marker_probe_func *probe_func;
};
struct sputrace {
ktime_t tstamp;
int owner_tid; /* owner */
int curr_tid;
const char *name;
int number;
};
static int bufsize __read_mostly = 16384;
MODULE_PARM_DESC(bufsize, "Log buffer size (number of records)");
module_param(bufsize, int, 0);
static DEFINE_SPINLOCK(sputrace_lock);
static DECLARE_WAIT_QUEUE_HEAD(sputrace_wait);
static ktime_t sputrace_start;
static unsigned long sputrace_head, sputrace_tail;
static struct sputrace *sputrace_log;
static int sputrace_used(void)
{
return (sputrace_head - sputrace_tail) % bufsize;
}
static inline int sputrace_avail(void)
{
return bufsize - sputrace_used();
}
static int sputrace_sprint(char *tbuf, int n)
{
const struct sputrace *t = sputrace_log + sputrace_tail % bufsize;
struct timespec tv =
ktime_to_timespec(ktime_sub(t->tstamp, sputrace_start));
return snprintf(tbuf, n,
"[%lu.%09lu] %d: %s (ctxthread = %d, spu = %d)\n",
(unsigned long) tv.tv_sec,
(unsigned long) tv.tv_nsec,
t->curr_tid,
t->name,
t->owner_tid,
t->number);
}
static ssize_t sputrace_read(struct file *file, char __user *buf,
size_t len, loff_t *ppos)
{
int error = 0, cnt = 0;
if (!buf || len < 0)
return -EINVAL;
while (cnt < len) {
char tbuf[128];
int width;
error = wait_event_interruptible(sputrace_wait,
sputrace_used() > 0);
if (error)
break;
spin_lock(&sputrace_lock);
if (sputrace_head == sputrace_tail) {
spin_unlock(&sputrace_lock);
continue;
}
width = sputrace_sprint(tbuf, sizeof(tbuf));
if (width < len)
sputrace_tail = (sputrace_tail + 1) % bufsize;
spin_unlock(&sputrace_lock);
if (width >= len)
break;
error = copy_to_user(buf + cnt, tbuf, width);
if (error)
break;
cnt += width;
}
return cnt == 0 ? error : cnt;
}
static int sputrace_open(struct inode *inode, struct file *file)
{
spin_lock(&sputrace_lock);
sputrace_head = sputrace_tail = 0;
sputrace_start = ktime_get();
spin_unlock(&sputrace_lock);
return 0;
}
static const struct file_operations sputrace_fops = {
.owner = THIS_MODULE,
.open = sputrace_open,
.read = sputrace_read,
};
static void sputrace_log_item(const char *name, struct spu_context *ctx,
struct spu *spu)
{
spin_lock(&sputrace_lock);
if (sputrace_avail() > 1) {
struct sputrace *t = sputrace_log + sputrace_head;
t->tstamp = ktime_get();
t->owner_tid = ctx->tid;
t->name = name;
t->curr_tid = current->pid;
t->number = spu ? spu->number : -1;
sputrace_head = (sputrace_head + 1) % bufsize;
} else {
printk(KERN_WARNING
"sputrace: lost samples due to full buffer.\n");
}
spin_unlock(&sputrace_lock);
wake_up(&sputrace_wait);
}
static void spu_context_event(void *probe_private, void *call_data,
const char *format, va_list *args)
{
struct spu_probe *p = probe_private;
struct spu_context *ctx;
struct spu *spu;
ctx = va_arg(*args, struct spu_context *);
spu = va_arg(*args, struct spu *);
sputrace_log_item(p->name, ctx, spu);
}
static void spu_context_nospu_event(void *probe_private, void *call_data,
const char *format, va_list *args)
{
struct spu_probe *p = probe_private;
struct spu_context *ctx;
ctx = va_arg(*args, struct spu_context *);
sputrace_log_item(p->name, ctx, NULL);
}
struct spu_probe spu_probes[] = {
{ "spu_bind_context__enter", "ctx %p spu %p", spu_context_event },
{ "spu_unbind_context__enter", "ctx %p spu %p", spu_context_event },
{ "spu_get_idle__enter", "ctx %p", spu_context_nospu_event },
{ "spu_get_idle__found", "ctx %p spu %p", spu_context_event },
{ "spu_get_idle__not_found", "ctx %p", spu_context_nospu_event },
{ "spu_find_victim__enter", "ctx %p", spu_context_nospu_event },
{ "spusched_tick__preempt", "ctx %p spu %p", spu_context_event },
{ "spusched_tick__newslice", "ctx %p", spu_context_nospu_event },
{ "spu_yield__enter", "ctx %p", spu_context_nospu_event },
{ "spu_deactivate__enter", "ctx %p", spu_context_nospu_event },
{ "__spu_deactivate__unload", "ctx %p spu %p", spu_context_event },
{ "spufs_ps_fault__enter", "ctx %p", spu_context_nospu_event },
{ "spufs_ps_fault__sleep", "ctx %p", spu_context_nospu_event },
{ "spufs_ps_fault__wake", "ctx %p spu %p", spu_context_event },
{ "spufs_ps_fault__insert", "ctx %p spu %p", spu_context_event },
{ "spu_acquire_saved__enter", "ctx %p", spu_context_nospu_event },
{ "destroy_spu_context__enter", "ctx %p", spu_context_nospu_event },
{ "spufs_stop_callback__enter", "ctx %p spu %p", spu_context_event },
};
static int __init sputrace_init(void)
{
struct proc_dir_entry *entry;
int i, error = -ENOMEM;
sputrace_log = kcalloc(bufsize, sizeof(struct sputrace), GFP_KERNEL);
if (!sputrace_log)
goto out;
entry = proc_create("sputrace", S_IRUSR, NULL, &sputrace_fops);
if (!entry)
goto out_free_log;
for (i = 0; i < ARRAY_SIZE(spu_probes); i++) {
struct spu_probe *p = &spu_probes[i];
error = marker_probe_register(p->name, p->format,
p->probe_func, p);
if (error)
printk(KERN_INFO "Unable to register probe %s\n",
p->name);
}
return 0;
out_free_log:
kfree(sputrace_log);
out:
return -ENOMEM;
}
static void __exit sputrace_exit(void)
{
int i;
for (i = 0; i < ARRAY_SIZE(spu_probes); i++)
marker_probe_unregister(spu_probes[i].name,
spu_probes[i].probe_func, &spu_probes[i]);
remove_proc_entry("sputrace", NULL);
kfree(sputrace_log);
marker_synchronize_unregister();
}
module_init(sputrace_init);
module_exit(sputrace_exit);
MODULE_LICENSE("GPL");