unsigned long __read_mostly tracing_max_latency;
unsigned long __read_mostly tracing_thresh;
+/*
+ * On boot up, the ring buffer is set to the minimum size, so that
+ * we do not waste memory on systems that are not using tracing.
+ */
+static int ring_buffer_expanded;
+
/*
* We need to change this state when a selftest is running.
* A selftest will lurk into the ring-buffer to count the
{
strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE);
default_bootup_tracer = bootup_tracer_buf;
+ /* We are using ftrace early, expand it */
+ ring_buffer_expanded = 1;
return 1;
}
__setup("ftrace=", set_ftrace);
__raw_spin_unlock(&trace_cmdline_lock);
}
-char *trace_find_cmdline(int pid)
+void trace_find_cmdline(int pid, char comm[])
{
- char *cmdline = "<...>";
unsigned map;
- if (!pid)
- return "<idle>";
+ if (!pid) {
+ strcpy(comm, "<idle>");
+ return;
+ }
- if (pid > PID_MAX_DEFAULT)
- goto out;
+ if (pid > PID_MAX_DEFAULT) {
+ strcpy(comm, "<...>");
+ return;
+ }
+ __raw_spin_lock(&trace_cmdline_lock);
map = map_pid_to_cmdline[pid];
if (map >= SAVED_CMDLINES)
goto out;
- cmdline = saved_cmdlines[map];
+ strcpy(comm, saved_cmdlines[map]);
out:
- return cmdline;
+ __raw_spin_unlock(&trace_cmdline_lock);
}
void tracing_record_cmdline(struct task_struct *tsk)
{
- if (atomic_read(&trace_record_cmdline_disabled))
+ if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on())
return;
trace_save_cmdline(tsk);
/**
- * trace_vprintk - write binary msg to tracing buffer
+ * trace_vbprintk - write binary msg to tracing buffer
*
*/
-int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args)
+int trace_vbprintk(unsigned long ip, int depth, const char *fmt, va_list args)
{
static raw_spinlock_t trace_buf_lock =
(raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
struct ring_buffer_event *event;
struct trace_array *tr = &global_trace;
struct trace_array_cpu *data;
- struct print_entry *entry;
+ struct bprint_entry *entry;
unsigned long flags;
int resched;
int cpu, len = 0, size, pc;
goto out_unlock;
size = sizeof(*entry) + sizeof(u32) * len;
- event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, flags, pc);
+ event = trace_buffer_lock_reserve(tr, TRACE_BPRINT, size, flags, pc);
if (!event)
goto out_unlock;
entry = ring_buffer_event_data(event);
return len;
}
+EXPORT_SYMBOL_GPL(trace_vbprintk);
+
+int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args)
+{
+ static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED;
+ static char trace_buf[TRACE_BUF_SIZE];
+
+ struct ring_buffer_event *event;
+ struct trace_array *tr = &global_trace;
+ struct trace_array_cpu *data;
+ int cpu, len = 0, size, pc;
+ struct print_entry *entry;
+ unsigned long irq_flags;
+
+ if (tracing_disabled || tracing_selftest_running)
+ return 0;
+
+ pc = preempt_count();
+ preempt_disable_notrace();
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+
+ if (unlikely(atomic_read(&data->disabled)))
+ goto out;
+
+ pause_graph_tracing();
+ raw_local_irq_save(irq_flags);
+ __raw_spin_lock(&trace_buf_lock);
+ len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args);
+
+ len = min(len, TRACE_BUF_SIZE-1);
+ trace_buf[len] = 0;
+
+ size = sizeof(*entry) + len + 1;
+ event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc);
+ if (!event)
+ goto out_unlock;
+ entry = ring_buffer_event_data(event);
+ entry->ip = ip;
+ entry->depth = depth;
+
+ memcpy(&entry->buf, trace_buf, len);
+ entry->buf[len] = 0;
+ ring_buffer_unlock_commit(tr->buffer, event);
+
+ out_unlock:
+ __raw_spin_unlock(&trace_buf_lock);
+ raw_local_irq_restore(irq_flags);
+ unpause_graph_tracing();
+ out:
+ preempt_enable_notrace();
+
+ return len;
+}
EXPORT_SYMBOL_GPL(trace_vprintk);
enum trace_file_type {
total = entries +
ring_buffer_overruns(iter->tr->buffer);
- seq_printf(m, "%s latency trace v1.1.5 on %s\n",
+ seq_printf(m, "# %s latency trace v1.1.5 on %s\n",
name, UTS_RELEASE);
- seq_puts(m, "-----------------------------------"
+ seq_puts(m, "# -----------------------------------"
"---------------------------------\n");
- seq_printf(m, " latency: %lu us, #%lu/%lu, CPU#%d |"
+ seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |"
" (M:%s VP:%d, KP:%d, SP:%d HP:%d",
nsecs_to_usecs(data->saved_latency),
entries,
#else
seq_puts(m, ")\n");
#endif
- seq_puts(m, " -----------------\n");
- seq_printf(m, " | task: %.16s-%d "
+ seq_puts(m, "# -----------------\n");
+ seq_printf(m, "# | task: %.16s-%d "
"(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n",
data->comm, data->pid, data->uid, data->nice,
data->policy, data->rt_priority);
- seq_puts(m, " -----------------\n");
+ seq_puts(m, "# -----------------\n");
if (data->critical_start) {
- seq_puts(m, " => started at: ");
+ seq_puts(m, "# => started at: ");
seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags);
trace_print_seq(m, &iter->seq);
- seq_puts(m, "\n => ended at: ");
+ seq_puts(m, "\n# => ended at: ");
seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags);
trace_print_seq(m, &iter->seq);
- seq_puts(m, "\n");
+ seq_puts(m, "#\n");
}
- seq_puts(m, "\n");
+ seq_puts(m, "#\n");
}
static void test_cpu_buff_start(struct trace_iterator *iter)
return TRACE_TYPE_HANDLED;
}
+static enum print_line_t print_bprintk_msg_only(struct trace_iterator *iter)
+{
+ struct trace_seq *s = &iter->seq;
+ struct trace_entry *entry = iter->ent;
+ struct bprint_entry *field;
+ int ret;
+
+ trace_assign_type(field, entry);
+
+ ret = trace_seq_bprintf(s, field->fmt, field->buf);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ return TRACE_TYPE_HANDLED;
+}
+
static enum print_line_t print_printk_msg_only(struct trace_iterator *iter)
{
struct trace_seq *s = &iter->seq;
trace_assign_type(field, entry);
- ret = trace_seq_bprintf(s, field->fmt, field->buf);
+ ret = trace_seq_printf(s, "%s", field->buf);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
{
int cpu;
+ /* If we are looking at one CPU buffer, only check that one */
+ if (iter->cpu_file != TRACE_PIPE_ALL_CPU) {
+ cpu = iter->cpu_file;
+ if (iter->buffer_iter[cpu]) {
+ if (!ring_buffer_iter_empty(iter->buffer_iter[cpu]))
+ return 0;
+ } else {
+ if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu))
+ return 0;
+ }
+ return 1;
+ }
+
for_each_tracing_cpu(cpu) {
if (iter->buffer_iter[cpu]) {
if (!ring_buffer_iter_empty(iter->buffer_iter[cpu]))
return ret;
}
+ if (iter->ent->type == TRACE_BPRINT &&
+ trace_flags & TRACE_ITER_PRINTK &&
+ trace_flags & TRACE_ITER_PRINTK_MSGONLY)
+ return print_bprintk_msg_only(iter);
+
if (iter->ent->type == TRACE_PRINT &&
trace_flags & TRACE_ITER_PRINTK &&
trace_flags & TRACE_ITER_PRINTK_MSGONLY)
iter->buffer_iter[cpu] =
ring_buffer_read_start(iter->tr->buffer, cpu);
-
- if (!iter->buffer_iter[cpu])
- goto fail_buffer;
}
} else {
cpu = iter->cpu_file;
iter->buffer_iter[cpu] =
ring_buffer_read_start(iter->tr->buffer, cpu);
-
- if (!iter->buffer_iter[cpu])
- goto fail;
}
/* TODO stop tracer */
return t->init(tr);
}
+static int tracing_resize_ring_buffer(unsigned long size)
+{
+ int ret;
+
+ /*
+ * If kernel or user changes the size of the ring buffer
+ * we use the size that was given, and we can forget about
+ * expanding it later.
+ */
+ ring_buffer_expanded = 1;
+
+ ret = ring_buffer_resize(global_trace.buffer, size);
+ if (ret < 0)
+ return ret;
+
+ ret = ring_buffer_resize(max_tr.buffer, size);
+ if (ret < 0) {
+ int r;
+
+ r = ring_buffer_resize(global_trace.buffer,
+ global_trace.entries);
+ if (r < 0) {
+ /*
+ * AARGH! We are left with different
+ * size max buffer!!!!
+ * The max buffer is our "snapshot" buffer.
+ * When a tracer needs a snapshot (one of the
+ * latency tracers), it swaps the max buffer
+ * with the saved snap shot. We succeeded to
+ * update the size of the main buffer, but failed to
+ * update the size of the max buffer. But when we tried
+ * to reset the main buffer to the original size, we
+ * failed there too. This is very unlikely to
+ * happen, but if it does, warn and kill all
+ * tracing.
+ */
+ WARN_ON(1);
+ tracing_disabled = 1;
+ }
+ return ret;
+ }
+
+ global_trace.entries = size;
+
+ return ret;
+}
+
+/**
+ * tracing_update_buffers - used by tracing facility to expand ring buffers
+ *
+ * To save on memory when the tracing is never used on a system with it
+ * configured in. The ring buffers are set to a minimum size. But once
+ * a user starts to use the tracing facility, then they need to grow
+ * to their default size.
+ *
+ * This function is to be called when a tracer is about to be used.
+ */
+int tracing_update_buffers(void)
+{
+ int ret = 0;
+
+ mutex_lock(&trace_types_lock);
+ if (!ring_buffer_expanded)
+ ret = tracing_resize_ring_buffer(trace_buf_size);
+ mutex_unlock(&trace_types_lock);
+
+ return ret;
+}
+
struct trace_option_dentry;
static struct trace_option_dentry *
int ret = 0;
mutex_lock(&trace_types_lock);
+
+ if (!ring_buffer_expanded) {
+ ret = tracing_resize_ring_buffer(trace_buf_size);
+ if (ret < 0)
+ goto out;
+ ret = 0;
+ }
+
for (t = trace_types; t; t = t->next) {
if (strcmp(t->name, buf) == 0)
break;
size_t cnt, loff_t *ppos)
{
struct trace_array *tr = filp->private_data;
- char buf[64];
+ char buf[96];
int r;
- r = sprintf(buf, "%lu\n", tr->entries >> 10);
+ mutex_lock(&trace_types_lock);
+ if (!ring_buffer_expanded)
+ r = sprintf(buf, "%lu (expanded: %lu)\n",
+ tr->entries >> 10,
+ trace_buf_size >> 10);
+ else
+ r = sprintf(buf, "%lu\n", tr->entries >> 10);
+ mutex_unlock(&trace_types_lock);
+
return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}
val <<= 10;
if (val != global_trace.entries) {
- ret = ring_buffer_resize(global_trace.buffer, val);
+ ret = tracing_resize_ring_buffer(val);
if (ret < 0) {
cnt = ret;
goto out;
}
-
- ret = ring_buffer_resize(max_tr.buffer, val);
- if (ret < 0) {
- int r;
- cnt = ret;
- r = ring_buffer_resize(global_trace.buffer,
- global_trace.entries);
- if (r < 0) {
- /* AARGH! We are left with different
- * size max buffer!!!! */
- WARN_ON(1);
- tracing_disabled = 1;
- }
- goto out;
- }
-
- global_trace.entries = val;
}
filp->f_pos += cnt;
(void *) cpu, &tracing_fops);
if (!entry)
pr_warning("Could not create debugfs 'trace' entry\n");
+
+ entry = debugfs_create_file("trace_pipe_raw", 0444, d_cpu,
+ (void *) cpu, &tracing_buffers_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'trace_pipe_raw' entry\n");
}
#ifdef CONFIG_FTRACE_SELFTEST
static __init int tracer_init_debugfs(void)
{
struct dentry *d_tracer;
- struct dentry *buffers;
struct dentry *entry;
int cpu;
pr_warning("Could not create debugfs "
"'trace_marker' entry\n");
- buffers = debugfs_create_dir("binary_buffers", d_tracer);
-
- if (!buffers)
- pr_warning("Could not create buffers directory\n");
- else {
- int cpu;
- char buf[64];
-
- for_each_tracing_cpu(cpu) {
- sprintf(buf, "%d", cpu);
-
- entry = debugfs_create_file(buf, 0444, buffers,
- (void *)(long)cpu,
- &tracing_buffers_fops);
- if (!entry)
- pr_warning("Could not create debugfs buffers "
- "'%s' entry\n", buf);
- }
- }
-
#ifdef CONFIG_DYNAMIC_FTRACE
entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer,
&ftrace_update_tot_cnt,
__init static int tracer_alloc_buffers(void)
{
struct trace_array_cpu *data;
+ int ring_buf_size;
int i;
int ret = -ENOMEM;
if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL))
goto out_free_tracing_cpumask;
+ /* To save memory, keep the ring buffer size to its minimum */
+ if (ring_buffer_expanded)
+ ring_buf_size = trace_buf_size;
+ else
+ ring_buf_size = 1;
+
cpumask_copy(tracing_buffer_mask, cpu_possible_mask);
cpumask_copy(tracing_cpumask, cpu_all_mask);
cpumask_clear(tracing_reader_cpumask);
/* TODO: make the number of buffers hot pluggable with CPUS */
- global_trace.buffer = ring_buffer_alloc(trace_buf_size,
+ global_trace.buffer = ring_buffer_alloc(ring_buf_size,
TRACE_BUFFER_FLAGS);
if (!global_trace.buffer) {
printk(KERN_ERR "tracer: failed to allocate ring buffer!\n");
#ifdef CONFIG_TRACER_MAX_TRACE
- max_tr.buffer = ring_buffer_alloc(trace_buf_size,
+ max_tr.buffer = ring_buffer_alloc(ring_buf_size,
TRACE_BUFFER_FLAGS);
if (!max_tr.buffer) {
printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n");
&trace_panic_notifier);
register_die_notifier(&trace_die_notifier);
- ret = 0;
+
+ return 0;
out_free_cpumask:
free_cpumask_var(tracing_reader_cpumask);
projects / linux-2.6-omap-h63xx.git / blobdiff