TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE;
static int trace_stop_count;
-static DEFINE_SPINLOCK(tracing_start_lock);
+static DEFINE_RAW_SPINLOCK(tracing_start_lock);
static void wakeup_work_handler(struct work_struct *work)
{
} trace_clocks[] = {
{ trace_clock_local, "local" },
{ trace_clock_global, "global" },
+ { trace_clock_counter, "counter" },
};
int trace_clock_id;
if (isspace(ch)) {
parser->buffer[parser->idx] = 0;
parser->cont = false;
- } else {
+ } else if (parser->idx < parser->size - 1) {
parser->cont = true;
parser->buffer[parser->idx++] = ch;
+ } else {
+ ret = -EINVAL;
+ goto out;
}
*ppos += read;
memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN);
max_data->pid = tsk->pid;
- max_data->uid = task_uid(tsk);
+ /*
+ * If tsk == current, then use current_uid(), as that does not use
+ * RCU. The irq tracer can be called out of RCU scope.
+ */
+ if (tsk == current)
+ max_data->uid = current_uid();
+ else
+ max_data->uid = task_uid(tsk);
+
max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO;
max_data->policy = tsk->policy;
max_data->rt_priority = tsk->rt_priority;
void
update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
{
- struct ring_buffer *buf = tr->buffer;
+ struct ring_buffer *buf;
if (trace_stop_count)
return;
}
arch_spin_lock(&ftrace_max_lock);
+ buf = tr->buffer;
tr->buffer = max_tr.buffer;
max_tr.buffer = buf;
if (tracing_disabled)
return;
- spin_lock_irqsave(&tracing_start_lock, flags);
+ raw_spin_lock_irqsave(&tracing_start_lock, flags);
if (--trace_stop_count) {
if (trace_stop_count < 0) {
/* Someone screwed up their debugging */
ftrace_start();
out:
- spin_unlock_irqrestore(&tracing_start_lock, flags);
+ raw_spin_unlock_irqrestore(&tracing_start_lock, flags);
}
/**
unsigned long flags;
ftrace_stop();
- spin_lock_irqsave(&tracing_start_lock, flags);
+ raw_spin_lock_irqsave(&tracing_start_lock, flags);
if (trace_stop_count++)
goto out;
arch_spin_unlock(&ftrace_max_lock);
out:
- spin_unlock_irqrestore(&tracing_start_lock, flags);
+ raw_spin_unlock_irqrestore(&tracing_start_lock, flags);
}
void trace_stop_cmdline_recording(void);
arch_spin_lock(&trace_cmdline_lock);
map = map_pid_to_cmdline[pid];
if (map != NO_CMDLINE_MAP)
- strcpy(comm, saved_cmdlines[map]);
+ strlcpy(comm, saved_cmdlines[map], TASK_COMM_LEN);
else
strcpy(comm, "<...>");
int cpu_file = iter->cpu_file;
u64 next_ts = 0, ts;
int next_cpu = -1;
+ int next_size = 0;
int cpu;
/*
next_cpu = cpu;
next_ts = ts;
next_lost = lost_events;
+ next_size = iter->ent_size;
}
}
+ iter->ent_size = next_size;
+
if (ent_cpu)
*ent_cpu = next_cpu;
}
}
+static void test_ftrace_alive(struct seq_file *m)
+{
+ if (!ftrace_is_dead())
+ return;
+ seq_printf(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n");
+ seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n");
+}
+
static int s_show(struct seq_file *m, void *v)
{
struct trace_iterator *iter = v;
if (iter->tr) {
seq_printf(m, "# tracer: %s\n", iter->trace->name);
seq_puts(m, "#\n");
+ test_ftrace_alive(m);
}
if (iter->trace && iter->trace->print_header)
iter->trace->print_header(m);
if (cpumask_test_cpu(cpu, tracing_cpumask) &&
!cpumask_test_cpu(cpu, tracing_cpumask_new)) {
atomic_inc(&global_trace.data[cpu]->disabled);
+ ring_buffer_record_disable_cpu(global_trace.buffer, cpu);
}
if (!cpumask_test_cpu(cpu, tracing_cpumask) &&
cpumask_test_cpu(cpu, tracing_cpumask_new)) {
atomic_dec(&global_trace.data[cpu]->disabled);
+ ring_buffer_record_enable_cpu(global_trace.buffer, cpu);
}
}
arch_spin_unlock(&ftrace_max_lock);
return -EINVAL;
}
-static void set_tracer_flags(unsigned int mask, int enabled)
+/* Some tracers require overwrite to stay enabled */
+int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set)
+{
+ if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set)
+ return -1;
+
+ return 0;
+}
+
+int set_tracer_flag(unsigned int mask, int enabled)
{
/* do nothing if flag is already set */
if (!!(trace_flags & mask) == !!enabled)
- return;
+ return 0;
+
+ /* Give the tracer a chance to approve the change */
+ if (current_trace->flag_changed)
+ if (current_trace->flag_changed(current_trace, mask, !!enabled))
+ return -EINVAL;
if (enabled)
trace_flags |= mask;
if (mask == TRACE_ITER_RECORD_CMD)
trace_event_enable_cmd_record(enabled);
- if (mask == TRACE_ITER_OVERWRITE)
+ if (mask == TRACE_ITER_OVERWRITE) {
ring_buffer_change_overwrite(global_trace.buffer, enabled);
+#ifdef CONFIG_TRACER_MAX_TRACE
+ ring_buffer_change_overwrite(max_tr.buffer, enabled);
+#endif
+ }
+
+ return 0;
}
static ssize_t
char buf[64];
char *cmp;
int neg = 0;
- int ret;
+ int ret = 0;
int i;
if (cnt >= sizeof(buf))
cmp += 2;
}
+ mutex_lock(&trace_types_lock);
+
for (i = 0; trace_options[i]; i++) {
if (strcmp(cmp, trace_options[i]) == 0) {
- set_tracer_flags(1 << i, !neg);
+ ret = set_tracer_flag(1 << i, !neg);
break;
}
}
/* If no option could be set, test the specific tracer options */
- if (!trace_options[i]) {
- mutex_lock(&trace_types_lock);
+ if (!trace_options[i])
ret = set_tracer_option(current_trace, cmp, neg);
- mutex_unlock(&trace_types_lock);
- if (ret)
- return ret;
- }
+
+ mutex_unlock(&trace_types_lock);
+
+ if (ret)
+ return ret;
*ppos += cnt;
"# cat /sys/kernel/debug/tracing/trace_options\n"
"noprint-parent nosym-offset nosym-addr noverbose\n"
"# echo print-parent > /sys/kernel/debug/tracing/trace_options\n"
- "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n"
+ "# echo 1 > /sys/kernel/debug/tracing/tracing_on\n"
"# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n"
- "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n"
+ "# echo 0 > /sys/kernel/debug/tracing/tracing_on\n"
;
static ssize_t
goto out;
trace_branch_disable();
+
+ current_trace->enabled = false;
+
if (current_trace && current_trace->reset)
current_trace->reset(tr);
if (current_trace && current_trace->use_max_tr) {
goto out;
}
+ current_trace->enabled = true;
trace_branch_enable(tr);
out:
mutex_unlock(&trace_types_lock);
*/
return POLLIN | POLLRDNORM;
} else {
- if (!trace_empty(iter))
- return POLLIN | POLLRDNORM;
poll_wait(filp, &trace_wait, poll_table);
if (!trace_empty(iter))
return POLLIN | POLLRDNORM;
static struct tracer *old_tracer;
ssize_t sret;
- /* return any leftover data */
- sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
- if (sret != -EBUSY)
- return sret;
-
- trace_seq_init(&iter->seq);
-
/* copy the tracer to avoid using a global lock all around */
mutex_lock(&trace_types_lock);
if (unlikely(old_tracer != current_trace && current_trace)) {
* is protected.
*/
mutex_lock(&iter->mutex);
+
+ /* return any leftover data */
+ sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
+ if (sret != -EBUSY)
+ goto out;
+
+ trace_seq_init(&iter->seq);
+
if (iter->trace->read) {
sret = iter->trace->read(iter, filp, ubuf, cnt, ppos);
if (sret)
memset(&iter->seq, 0,
sizeof(struct trace_iterator) -
offsetof(struct trace_iterator, seq));
+ cpumask_clear(iter->started);
iter->pos = -1;
trace_event_read_lock();
.pages = pages_def,
.partial = partial_def,
.nr_pages = 0, /* This gets updated below. */
+ .nr_pages_max = PIPE_DEF_BUFFERS,
.flags = flags,
.ops = &tracing_pipe_buf_ops,
.spd_release = tracing_spd_release_pipe,
spd.nr_pages = i;
- ret = splice_to_pipe(pipe, &spd);
+ if (i)
+ ret = splice_to_pipe(pipe, &spd);
+ else
+ ret = 0;
out:
- splice_shrink_spd(pipe, &spd);
+ splice_shrink_spd(&spd);
return ret;
out_err:
return cnt;
}
+static ssize_t
+tracing_total_entries_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ struct trace_array *tr = filp->private_data;
+ char buf[64];
+ int r, cpu;
+ unsigned long size = 0, expanded_size = 0;
+
+ mutex_lock(&trace_types_lock);
+ for_each_tracing_cpu(cpu) {
+ size += tr->entries >> 10;
+ if (!ring_buffer_expanded)
+ expanded_size += trace_buf_size >> 10;
+ }
+ if (ring_buffer_expanded)
+ r = sprintf(buf, "%lu\n", size);
+ else
+ r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size);
+ mutex_unlock(&trace_types_lock);
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
static ssize_t
tracing_free_buffer_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
return 0;
}
-static int mark_printk(const char *fmt, ...)
-{
- int ret;
- va_list args;
- va_start(args, fmt);
- ret = trace_vprintk(0, fmt, args);
- va_end(args);
- return ret;
-}
-
static ssize_t
tracing_mark_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *fpos)
{
- char *buf;
- size_t written;
+ unsigned long addr = (unsigned long)ubuf;
+ struct ring_buffer_event *event;
+ struct ring_buffer *buffer;
+ struct print_entry *entry;
+ unsigned long irq_flags;
+ struct page *pages[2];
+ int nr_pages = 1;
+ ssize_t written;
+ void *page1;
+ void *page2;
+ int offset;
+ int size;
+ int len;
+ int ret;
if (tracing_disabled)
return -EINVAL;
if (cnt > TRACE_BUF_SIZE)
cnt = TRACE_BUF_SIZE;
- buf = kmalloc(cnt + 2, GFP_KERNEL);
- if (buf == NULL)
- return -ENOMEM;
+ /*
+ * Userspace is injecting traces into the kernel trace buffer.
+ * We want to be as non intrusive as possible.
+ * To do so, we do not want to allocate any special buffers
+ * or take any locks, but instead write the userspace data
+ * straight into the ring buffer.
+ *
+ * First we need to pin the userspace buffer into memory,
+ * which, most likely it is, because it just referenced it.
+ * But there's no guarantee that it is. By using get_user_pages_fast()
+ * and kmap_atomic/kunmap_atomic() we can get access to the
+ * pages directly. We then write the data directly into the
+ * ring buffer.
+ */
+ BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE);
- if (copy_from_user(buf, ubuf, cnt)) {
- kfree(buf);
- return -EFAULT;
+ /* check if we cross pages */
+ if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK))
+ nr_pages = 2;
+
+ offset = addr & (PAGE_SIZE - 1);
+ addr &= PAGE_MASK;
+
+ ret = get_user_pages_fast(addr, nr_pages, 0, pages);
+ if (ret < nr_pages) {
+ while (--ret >= 0)
+ put_page(pages[ret]);
+ written = -EFAULT;
+ goto out;
}
- if (buf[cnt-1] != '\n') {
- buf[cnt] = '\n';
- buf[cnt+1] = '\0';
+
+ page1 = kmap_atomic(pages[0]);
+ if (nr_pages == 2)
+ page2 = kmap_atomic(pages[1]);
+
+ local_save_flags(irq_flags);
+ size = sizeof(*entry) + cnt + 2; /* possible \n added */
+ buffer = global_trace.buffer;
+ event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size,
+ irq_flags, preempt_count());
+ if (!event) {
+ /* Ring buffer disabled, return as if not open for write */
+ written = -EBADF;
+ goto out_unlock;
+ }
+
+ entry = ring_buffer_event_data(event);
+ entry->ip = _THIS_IP_;
+
+ if (nr_pages == 2) {
+ len = PAGE_SIZE - offset;
+ memcpy(&entry->buf, page1 + offset, len);
+ memcpy(&entry->buf[len], page2, cnt - len);
} else
- buf[cnt] = '\0';
+ memcpy(&entry->buf, page1 + offset, cnt);
- written = mark_printk("%s", buf);
- kfree(buf);
- *fpos += written;
+ if (entry->buf[cnt - 1] != '\n') {
+ entry->buf[cnt] = '\n';
+ entry->buf[cnt + 1] = '\0';
+ } else
+ entry->buf[cnt] = '\0';
- /* don't tell userspace we wrote more - it might confuse them */
- if (written > cnt)
- written = cnt;
+ ring_buffer_unlock_commit(buffer, event);
+
+ written = cnt;
+ *fpos += written;
+
+ out_unlock:
+ if (nr_pages == 2)
+ kunmap_atomic(page2);
+ kunmap_atomic(page1);
+ while (nr_pages > 0)
+ put_page(pages[--nr_pages]);
+ out:
return written;
}
.llseek = generic_file_llseek,
};
+static const struct file_operations tracing_total_entries_fops = {
+ .open = tracing_open_generic,
+ .read = tracing_total_entries_read,
+ .llseek = generic_file_llseek,
+};
+
static const struct file_operations tracing_free_buffer_fops = {
.write = tracing_free_buffer_write,
.release = tracing_free_buffer_release,
if (info->read < PAGE_SIZE)
goto read;
- info->read = 0;
-
trace_access_lock(info->cpu);
ret = ring_buffer_read_page(info->tr->buffer,
&info->spare,
if (ret < 0)
return 0;
+ info->read = 0;
+
read:
size = PAGE_SIZE - info->read;
if (size > count)
struct splice_pipe_desc spd = {
.pages = pages_def,
.partial = partial_def,
+ .nr_pages_max = PIPE_DEF_BUFFERS,
.flags = flags,
.ops = &buffer_pipe_buf_ops,
.spd_release = buffer_spd_release,
}
ret = splice_to_pipe(pipe, &spd);
- splice_shrink_spd(pipe, &spd);
+ splice_shrink_spd(&spd);
out:
return ret;
}
struct trace_array *tr = &global_trace;
struct trace_seq *s;
unsigned long cnt;
+ unsigned long long t;
+ unsigned long usec_rem;
s = kmalloc(sizeof(*s), GFP_KERNEL);
if (!s)
cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu);
trace_seq_printf(s, "commit overrun: %ld\n", cnt);
+ cnt = ring_buffer_bytes_cpu(tr->buffer, cpu);
+ trace_seq_printf(s, "bytes: %ld\n", cnt);
+
+ t = ns2usecs(ring_buffer_oldest_event_ts(tr->buffer, cpu));
+ usec_rem = do_div(t, USEC_PER_SEC);
+ trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", t, usec_rem);
+
+ t = ns2usecs(ring_buffer_time_stamp(tr->buffer, cpu));
+ usec_rem = do_div(t, USEC_PER_SEC);
+ trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem);
+
count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len);
kfree(s);
if (val != 0 && val != 1)
return -EINVAL;
- set_tracer_flags(1 << index, val);
+
+ mutex_lock(&trace_types_lock);
+ ret = set_tracer_flag(1 << index, val);
+ mutex_unlock(&trace_types_lock);
+
+ if (ret < 0)
+ return ret;
*ppos += cnt;
trace_access_lock_init();
d_tracer = tracing_init_dentry();
+ if (!d_tracer)
+ return 0;
trace_create_file("tracing_enabled", 0644, d_tracer,
&global_trace, &tracing_ctrl_fops);
trace_create_file("buffer_size_kb", 0644, d_tracer,
&global_trace, &tracing_entries_fops);
+ trace_create_file("buffer_total_size_kb", 0444, d_tracer,
+ &global_trace, &tracing_total_entries_fops);
+
trace_create_file("free_buffer", 0644, d_tracer,
&global_trace, &tracing_free_buffer_fops);
iter->cpu_file = TRACE_PIPE_ALL_CPU;
}
-static void
-__ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode)
+void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
{
- static arch_spinlock_t ftrace_dump_lock =
- (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
/* use static because iter can be a bit big for the stack */
static struct trace_iterator iter;
+ static atomic_t dump_running;
unsigned int old_userobj;
- static int dump_ran;
unsigned long flags;
int cnt = 0, cpu;
- /* only one dump */
- local_irq_save(flags);
- arch_spin_lock(&ftrace_dump_lock);
- if (dump_ran)
- goto out;
-
- dump_ran = 1;
+ /* Only allow one dump user at a time. */
+ if (atomic_inc_return(&dump_running) != 1) {
+ atomic_dec(&dump_running);
+ return;
+ }
+ /*
+ * Always turn off tracing when we dump.
+ * We don't need to show trace output of what happens
+ * between multiple crashes.
+ *
+ * If the user does a sysrq-z, then they can re-enable
+ * tracing with echo 1 > tracing_on.
+ */
tracing_off();
- if (disable_tracing)
- ftrace_kill();
+ local_irq_save(flags);
trace_init_global_iter(&iter);
printk(KERN_TRACE "Dumping ftrace buffer:\n");
+ /* Did function tracer already get disabled? */
+ if (ftrace_is_dead()) {
+ printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n");
+ printk("# MAY BE MISSING FUNCTION EVENTS\n");
+ }
+
/*
* We need to stop all tracing on all CPUS to read the
* the next buffer. This is a bit expensive, but is
printk(KERN_TRACE "---------------------------------\n");
out_enable:
- /* Re-enable tracing if requested */
- if (!disable_tracing) {
- trace_flags |= old_userobj;
+ trace_flags |= old_userobj;
- for_each_tracing_cpu(cpu) {
- atomic_dec(&iter.tr->data[cpu]->disabled);
- }
- tracing_on();
+ for_each_tracing_cpu(cpu) {
+ atomic_dec(&iter.tr->data[cpu]->disabled);
}
-
- out:
- arch_spin_unlock(&ftrace_dump_lock);
+ atomic_dec(&dump_running);
local_irq_restore(flags);
}
-
-/* By default: disable tracing after the dump */
-void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
-{
- __ftrace_dump(true, oops_dump_mode);
-}
+EXPORT_SYMBOL_GPL(ftrace_dump);
__init static int tracer_alloc_buffers(void)
{
git.openpandora.org / pandora-kernel.git / blobdiff