tracing: Move trace_flags from global to a trace_array field
In preparation to make trace options per instance, the global trace_flags
needs to be moved from being a global variable to a field within the trace
instance trace_array structure.
There's still more work to do, as there's some functions that use
trace_flags without passing in a way to get to the current_trace array. For
those, the global_trace is used directly (from trace.c). This includes
setting and clearing the trace_flags. This means that when a new instance is
created, it just gets the trace_flags of the global_trace and will not be
able to modify them. Depending on the functions that have access to the
trace_array, the flags of an instance may not affect parts of its trace,
where the global_trace is used. These will be fixed in future changes.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index e26933c..4e82f4a 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -250,6 +250,14 @@
return nsec;
}
+/* trace_flags holds trace_options default values */
+#define TRACE_DEFAULT_FLAGS \
+ (FUNCTION_DEFAULT_FLAGS | \
+ TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | \
+ TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | \
+ TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | \
+ TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS)
+
/*
* The global_trace is the descriptor that holds the tracing
* buffers for the live tracing. For each CPU, it contains
@@ -262,7 +270,9 @@
* pages for the buffer for that CPU. Each CPU has the same number
* of pages allocated for its buffer.
*/
-static struct trace_array global_trace;
+static struct trace_array global_trace = {
+ .trace_flags = TRACE_DEFAULT_FLAGS,
+};
LIST_HEAD(ftrace_trace_arrays);
@@ -490,15 +500,6 @@
#endif
-/* trace_flags holds trace_options default values */
-unsigned long trace_flags =
- FUNCTION_DEFAULT_FLAGS |
- TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK |
- TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO |
- TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE |
- TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS
- ;
-
static void tracer_tracing_on(struct trace_array *tr)
{
if (tr->trace_buffer.buffer)
@@ -543,7 +544,7 @@
int alloc;
int pc;
- if (!(trace_flags & TRACE_ITER_PRINTK))
+ if (!(global_trace.trace_flags & TRACE_ITER_PRINTK))
return 0;
pc = preempt_count();
@@ -593,7 +594,7 @@
int size = sizeof(struct bputs_entry);
int pc;
- if (!(trace_flags & TRACE_ITER_PRINTK))
+ if (!(global_trace.trace_flags & TRACE_ITER_PRINTK))
return 0;
pc = preempt_count();
@@ -1875,7 +1876,7 @@
unsigned long flags,
int skip, int pc, struct pt_regs *regs)
{
- if (!(trace_flags & TRACE_ITER_STACKTRACE))
+ if (!(global_trace.trace_flags & TRACE_ITER_STACKTRACE))
return;
__ftrace_trace_stack(buffer, flags, skip, pc, regs);
@@ -1919,7 +1920,7 @@
struct userstack_entry *entry;
struct stack_trace trace;
- if (!(trace_flags & TRACE_ITER_USERSTACKTRACE))
+ if (!(global_trace.trace_flags & TRACE_ITER_USERSTACKTRACE))
return;
/*
@@ -2236,7 +2237,7 @@
int ret;
va_list ap;
- if (!(trace_flags & TRACE_ITER_PRINTK))
+ if (!(global_trace.trace_flags & TRACE_ITER_PRINTK))
return 0;
va_start(ap, fmt);
@@ -2251,7 +2252,7 @@
int ret;
va_list ap;
- if (!(trace_flags & TRACE_ITER_PRINTK))
+ if (!(global_trace.trace_flags & TRACE_ITER_PRINTK))
return 0;
va_start(ap, fmt);
@@ -2592,7 +2593,7 @@
void
print_trace_header(struct seq_file *m, struct trace_iterator *iter)
{
- unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
+ unsigned long sym_flags = (global_trace.trace_flags & TRACE_ITER_SYM_MASK);
struct trace_buffer *buf = iter->trace_buffer;
struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu);
struct tracer *type = iter->trace;
@@ -2654,8 +2655,9 @@
static void test_cpu_buff_start(struct trace_iterator *iter)
{
struct trace_seq *s = &iter->seq;
+ struct trace_array *tr = iter->tr;
- if (!(trace_flags & TRACE_ITER_ANNOTATE))
+ if (!(tr->trace_flags & TRACE_ITER_ANNOTATE))
return;
if (!(iter->iter_flags & TRACE_FILE_ANNOTATE))
@@ -2677,8 +2679,9 @@
static enum print_line_t print_trace_fmt(struct trace_iterator *iter)
{
+ struct trace_array *tr = iter->tr;
struct trace_seq *s = &iter->seq;
- unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
+ unsigned long sym_flags = (tr->trace_flags & TRACE_ITER_SYM_MASK);
struct trace_entry *entry;
struct trace_event *event;
@@ -2688,7 +2691,7 @@
event = ftrace_find_event(entry->type);
- if (trace_flags & TRACE_ITER_CONTEXT_INFO) {
+ if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) {
if (iter->iter_flags & TRACE_FILE_LAT_FMT)
trace_print_lat_context(iter);
else
@@ -2708,13 +2711,14 @@
static enum print_line_t print_raw_fmt(struct trace_iterator *iter)
{
+ struct trace_array *tr = iter->tr;
struct trace_seq *s = &iter->seq;
struct trace_entry *entry;
struct trace_event *event;
entry = iter->ent;
- if (trace_flags & TRACE_ITER_CONTEXT_INFO)
+ if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO)
trace_seq_printf(s, "%d %d %llu ",
entry->pid, iter->cpu, iter->ts);
@@ -2732,6 +2736,7 @@
static enum print_line_t print_hex_fmt(struct trace_iterator *iter)
{
+ struct trace_array *tr = iter->tr;
struct trace_seq *s = &iter->seq;
unsigned char newline = '\n';
struct trace_entry *entry;
@@ -2739,7 +2744,7 @@
entry = iter->ent;
- if (trace_flags & TRACE_ITER_CONTEXT_INFO) {
+ if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) {
SEQ_PUT_HEX_FIELD(s, entry->pid);
SEQ_PUT_HEX_FIELD(s, iter->cpu);
SEQ_PUT_HEX_FIELD(s, iter->ts);
@@ -2761,13 +2766,14 @@
static enum print_line_t print_bin_fmt(struct trace_iterator *iter)
{
+ struct trace_array *tr = iter->tr;
struct trace_seq *s = &iter->seq;
struct trace_entry *entry;
struct trace_event *event;
entry = iter->ent;
- if (trace_flags & TRACE_ITER_CONTEXT_INFO) {
+ if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) {
SEQ_PUT_FIELD(s, entry->pid);
SEQ_PUT_FIELD(s, iter->cpu);
SEQ_PUT_FIELD(s, iter->ts);
@@ -2816,6 +2822,8 @@
/* Called with trace_event_read_lock() held. */
enum print_line_t print_trace_line(struct trace_iterator *iter)
{
+ struct trace_array *tr = iter->tr;
+ unsigned long trace_flags = tr->trace_flags;
enum print_line_t ret;
if (iter->lost_events) {
@@ -2861,6 +2869,7 @@
void trace_latency_header(struct seq_file *m)
{
struct trace_iterator *iter = m->private;
+ struct trace_array *tr = iter->tr;
/* print nothing if the buffers are empty */
if (trace_empty(iter))
@@ -2869,13 +2878,15 @@
if (iter->iter_flags & TRACE_FILE_LAT_FMT)
print_trace_header(m, iter);
- if (!(trace_flags & TRACE_ITER_VERBOSE))
+ if (!(tr->trace_flags & TRACE_ITER_VERBOSE))
print_lat_help_header(m);
}
void trace_default_header(struct seq_file *m)
{
struct trace_iterator *iter = m->private;
+ struct trace_array *tr = iter->tr;
+ unsigned long trace_flags = tr->trace_flags;
if (!(trace_flags & TRACE_ITER_CONTEXT_INFO))
return;
@@ -3220,7 +3231,7 @@
iter = __tracing_open(inode, file, false);
if (IS_ERR(iter))
ret = PTR_ERR(iter);
- else if (trace_flags & TRACE_ITER_LATENCY_FMT)
+ else if (tr->trace_flags & TRACE_ITER_LATENCY_FMT)
iter->iter_flags |= TRACE_FILE_LAT_FMT;
}
@@ -3467,7 +3478,7 @@
trace_opts = tr->current_trace->flags->opts;
for (i = 0; trace_options[i]; i++) {
- if (trace_flags & (1 << i))
+ if (tr->trace_flags & (1 << i))
seq_printf(m, "%s\n", trace_options[i]);
else
seq_printf(m, "no%s\n", trace_options[i]);
@@ -3532,7 +3543,7 @@
int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled)
{
/* do nothing if flag is already set */
- if (!!(trace_flags & mask) == !!enabled)
+ if (!!(tr->trace_flags & mask) == !!enabled)
return 0;
/* Give the tracer a chance to approve the change */
@@ -3541,9 +3552,9 @@
return -EINVAL;
if (enabled)
- trace_flags |= mask;
+ tr->trace_flags |= mask;
else
- trace_flags &= ~mask;
+ tr->trace_flags &= ~mask;
if (mask == TRACE_ITER_RECORD_CMD)
trace_event_enable_cmd_record(enabled);
@@ -4558,7 +4569,7 @@
/* trace pipe does not show start of buffer */
cpumask_setall(iter->started);
- if (trace_flags & TRACE_ITER_LATENCY_FMT)
+ if (tr->trace_flags & TRACE_ITER_LATENCY_FMT)
iter->iter_flags |= TRACE_FILE_LAT_FMT;
/* Output in nanoseconds only if we are using a clock in nanoseconds. */
@@ -4615,11 +4626,13 @@
static unsigned int
trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table)
{
+ struct trace_array *tr = iter->tr;
+
/* Iterators are static, they should be filled or empty */
if (trace_buffer_iter(iter, iter->cpu_file))
return POLLIN | POLLRDNORM;
- if (trace_flags & TRACE_ITER_BLOCK)
+ if (tr->trace_flags & TRACE_ITER_BLOCK)
/*
* Always select as readable when in blocking mode
*/
@@ -5036,7 +5049,7 @@
struct trace_array *tr = inode->i_private;
/* disable tracing ? */
- if (trace_flags & TRACE_ITER_STOP_ON_FREE)
+ if (tr->trace_flags & TRACE_ITER_STOP_ON_FREE)
tracer_tracing_off(tr);
/* resize the ring buffer to 0 */
tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS);
@@ -5069,7 +5082,7 @@
if (tracing_disabled)
return -EINVAL;
- if (!(trace_flags & TRACE_ITER_MARKERS))
+ if (!(tr->trace_flags & TRACE_ITER_MARKERS))
return -EINVAL;
if (cnt > TRACE_BUF_SIZE)
@@ -6180,7 +6193,7 @@
long index = (long)filp->private_data;
char *buf;
- if (trace_flags & (1 << index))
+ if (global_trace.trace_flags & (1 << index))
buf = "1\n";
else
buf = "0\n";
@@ -6407,7 +6420,7 @@
{
enum ring_buffer_flags rb_flags;
- rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0;
+ rb_flags = tr->trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0;
buf->tr = tr;
@@ -6502,6 +6515,8 @@
if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL))
goto out_free_tr;
+ tr->trace_flags = global_trace.trace_flags;
+
cpumask_copy(tr->tracing_cpumask, cpu_all_mask);
raw_spin_lock_init(&tr->start_lock);
@@ -6938,6 +6953,7 @@
/* use static because iter can be a bit big for the stack */
static struct trace_iterator iter;
static atomic_t dump_running;
+ struct trace_array *tr = &global_trace;
unsigned int old_userobj;
unsigned long flags;
int cnt = 0, cpu;
@@ -6967,10 +6983,10 @@
atomic_inc(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled);
}
- old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ;
+ old_userobj = tr->trace_flags & TRACE_ITER_SYM_USEROBJ;
/* don't look at user memory in panic mode */
- trace_flags &= ~TRACE_ITER_SYM_USEROBJ;
+ tr->trace_flags &= ~TRACE_ITER_SYM_USEROBJ;
switch (oops_dump_mode) {
case DUMP_ALL:
@@ -7033,7 +7049,7 @@
printk(KERN_TRACE "---------------------------------\n");
out_enable:
- trace_flags |= old_userobj;
+ tr->trace_flags |= old_userobj;
for_each_tracing_cpu(cpu) {
atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled);
