static bool traceoff_after_boot __initdata;
static DEFINE_STATIC_KEY_FALSE(tracepoint_printk_key);
+/* Store tracers and their flags per instance */
+struct tracers {
+ struct list_head list;
+ struct tracer *tracer;
+ struct tracer_flags *flags;
+};
+
/*
* To prevent the comm cache from being overwritten when no
* tracing is active, only save the comm when a trace event
static int run_tracer_selftest(struct tracer *type)
{
struct trace_array *tr = &global_trace;
+ struct tracer_flags *saved_flags = tr->current_trace_flags;
struct tracer *saved_tracer = tr->current_trace;
int ret;
tracing_reset_online_cpus(&tr->array_buffer);
tr->current_trace = type;
+ tr->current_trace_flags = type->flags ? : type->default_flags;
#ifdef CONFIG_TRACER_MAX_TRACE
if (type->use_max_tr) {
ret = type->selftest(type, tr);
/* the test is responsible for resetting too */
tr->current_trace = saved_tracer;
+ tr->current_trace_flags = saved_flags;
if (ret) {
printk(KERN_CONT "FAILED!\n");
/* Add the warning after printing 'FAILED' */
}
#endif /* CONFIG_FTRACE_STARTUP_TEST */
-static int add_tracer_options(struct trace_array *tr, struct tracer *t);
+static int add_tracer(struct trace_array *tr, struct tracer *t);
static void __init apply_trace_boot_options(void);
+static void free_tracers(struct trace_array *tr)
+{
+ struct tracers *t, *n;
+
+ lockdep_assert_held(&trace_types_lock);
+
+ list_for_each_entry_safe(t, n, &tr->tracers, list) {
+ list_del(&t->list);
+ kfree(t->flags);
+ kfree(t);
+ }
+}
+
/**
* register_tracer - register a tracer with the ftrace system.
* @type: the plugin for the tracer
*/
int __init register_tracer(struct tracer *type)
{
+ struct trace_array *tr;
struct tracer *t;
int ret = 0;
if (ret < 0)
goto out;
- ret = add_tracer_options(&global_trace, type);
- if (ret < 0) {
- pr_warn("Failed to create tracer options for %s\n", type->name);
- goto out;
+ list_for_each_entry(tr, &ftrace_trace_arrays, list) {
+ ret = add_tracer(tr, type);
+ if (ret < 0) {
+ /* The tracer will still exist but without options */
+ pr_warn("Failed to create tracer options for %s\n", type->name);
+ break;
+ }
}
type->next = trace_types;
printk(KERN_INFO "Starting tracer '%s'\n", type->name);
/* Do we want this tracer to start on bootup? */
- tracing_set_tracer(&global_trace, type->name);
+ WARN_ON(tracing_set_tracer(&global_trace, type->name) < 0);
default_bootup_tracer = NULL;
apply_trace_boot_options();
{
struct tracer_opt *trace_opts;
struct trace_array *tr = m->private;
+ struct tracer_flags *flags;
struct tracer *trace;
u32 tracer_flags;
int i;
seq_printf(m, "no%s\n", trace_options[i]);
}
- trace = tr->current_trace;
- if (!trace->flags || !trace->flags->opts)
+ flags = tr->current_trace_flags;
+ if (!flags || !flags->opts)
return 0;
- tracer_flags = tr->current_trace->flags->val;
- trace_opts = tr->current_trace->flags->opts;
+ trace = tr->current_trace;
+
+ tracer_flags = flags->val;
+ trace_opts = flags->opts;
for (i = 0; trace_opts[i].name; i++) {
if (tracer_flags & trace_opts[i].bit)
/* Try to assign a tracer specific option */
static int set_tracer_option(struct trace_array *tr, char *cmp, int neg)
{
- struct tracer *trace = tr->current_trace;
- struct tracer_flags *tracer_flags = trace->flags;
+ struct tracer_flags *tracer_flags = tr->current_trace_flags;
struct tracer_opt *opts = NULL;
int i;
opts = &tracer_flags->opts[i];
if (strcmp(cmp, opts->name) == 0)
- return __set_tracer_option(tr, trace->flags, opts, neg);
+ return __set_tracer_option(tr, tracer_flags, opts, neg);
}
return -EINVAL;
return ret;
}
-struct trace_option_dentry;
-
-static int
-create_trace_option_files(struct trace_array *tr, struct tracer *tracer);
-
/*
* Used to clear out the tracer before deletion of an instance.
* Must have trace_types_lock held.
tr->current_trace->reset(tr);
tr->current_trace = &nop_trace;
+ tr->current_trace_flags = nop_trace.flags;
}
static bool tracer_options_updated;
-static int add_tracer_options(struct trace_array *tr, struct tracer *t)
-{
- /* Only enable if the directory has been created already. */
- if (!tr->dir && !(tr->flags & TRACE_ARRAY_FL_GLOBAL))
- return 0;
-
- /* Only create trace option files after update_tracer_options finish */
- if (!tracer_options_updated)
- return 0;
-
- return create_trace_option_files(tr, t);
-}
-
int tracing_set_tracer(struct trace_array *tr, const char *buf)
{
- struct tracer *t;
+ struct tracer *trace = NULL;
+ struct tracers *t;
#ifdef CONFIG_TRACER_MAX_TRACE
bool had_max_tr;
#endif
ret = 0;
}
- for (t = trace_types; t; t = t->next) {
- if (strcmp(t->name, buf) == 0)
+ list_for_each_entry(t, &tr->tracers, list) {
+ if (strcmp(t->tracer->name, buf) == 0) {
+ trace = t->tracer;
break;
+ }
}
- if (!t)
+ if (!trace)
return -EINVAL;
- if (t == tr->current_trace)
+ if (trace == tr->current_trace)
return 0;
#ifdef CONFIG_TRACER_SNAPSHOT
- if (t->use_max_tr) {
+ if (trace->use_max_tr) {
local_irq_disable();
arch_spin_lock(&tr->max_lock);
ret = tr->cond_snapshot ? -EBUSY : 0;
}
#endif
/* Some tracers won't work on kernel command line */
- if (system_state < SYSTEM_RUNNING && t->noboot) {
+ if (system_state < SYSTEM_RUNNING && trace->noboot) {
pr_warn("Tracer '%s' is not allowed on command line, ignored\n",
- t->name);
+ trace->name);
return -EINVAL;
}
/* Some tracers are only allowed for the top level buffer */
- if (!trace_ok_for_array(t, tr))
+ if (!trace_ok_for_array(trace, tr))
return -EINVAL;
/* If trace pipe files are being read, we can't change the tracer */
/* Current trace needs to be nop_trace before synchronize_rcu */
tr->current_trace = &nop_trace;
+ tr->current_trace_flags = nop_trace.flags;
- if (had_max_tr && !t->use_max_tr) {
+ if (had_max_tr && !trace->use_max_tr) {
/*
* We need to make sure that the update_max_tr sees that
* current_trace changed to nop_trace to keep it from
tracing_disarm_snapshot(tr);
}
- if (!had_max_tr && t->use_max_tr) {
+ if (!had_max_tr && trace->use_max_tr) {
ret = tracing_arm_snapshot_locked(tr);
if (ret)
return ret;
tr->current_trace = &nop_trace;
#endif
- if (t->init) {
- ret = tracer_init(t, tr);
+ tr->current_trace_flags = t->flags ? : t->tracer->flags;
+
+ if (trace->init) {
+ ret = tracer_init(trace, tr);
if (ret) {
#ifdef CONFIG_TRACER_MAX_TRACE
- if (t->use_max_tr)
+ if (trace->use_max_tr)
tracing_disarm_snapshot(tr);
#endif
+ tr->current_trace_flags = nop_trace.flags;
return ret;
}
}
- tr->current_trace = t;
+ tr->current_trace = trace;
tr->current_trace->enabled++;
trace_branch_enable(tr);
topt->entry = trace_create_file(opt->name, TRACE_MODE_WRITE,
t_options, topt, &trace_options_fops);
-
}
static int
-create_trace_option_files(struct trace_array *tr, struct tracer *tracer)
+create_trace_option_files(struct trace_array *tr, struct tracer *tracer,
+ struct tracer_flags *flags)
{
struct trace_option_dentry *topts;
struct trace_options *tr_topts;
- struct tracer_flags *flags;
struct tracer_opt *opts;
int cnt;
- int i;
-
- if (!tracer)
- return 0;
-
- flags = tracer->flags;
if (!flags || !flags->opts)
return 0;
- /*
- * If this is an instance, only create flags for tracers
- * the instance may have.
- */
- if (!trace_ok_for_array(tracer, tr))
- return 0;
-
- for (i = 0; i < tr->nr_topts; i++) {
- /* Make sure there's no duplicate flags. */
- if (WARN_ON_ONCE(tr->topts[i].tracer->flags == tracer->flags))
- return -EINVAL;
- }
-
opts = flags->opts;
for (cnt = 0; opts[cnt].name; cnt++)
return 0;
}
+static int get_global_flags_val(struct tracer *tracer)
+{
+ struct tracers *t;
+
+ list_for_each_entry(t, &global_trace.tracers, list) {
+ if (t->tracer != tracer)
+ continue;
+ if (!t->flags)
+ return -1;
+ return t->flags->val;
+ }
+ return -1;
+}
+
+static int add_tracer_options(struct trace_array *tr, struct tracers *t)
+{
+ struct tracer *tracer = t->tracer;
+ struct tracer_flags *flags = t->flags ?: tracer->flags;
+
+ if (!flags)
+ return 0;
+
+ /* Only add tracer options after update_tracer_options finish */
+ if (!tracer_options_updated)
+ return 0;
+
+ return create_trace_option_files(tr, tracer, flags);
+}
+
+static int add_tracer(struct trace_array *tr, struct tracer *tracer)
+{
+ struct tracer_flags *flags;
+ struct tracers *t;
+ int ret;
+
+ /* Only enable if the directory has been created already. */
+ if (!tr->dir && !(tr->flags & TRACE_ARRAY_FL_GLOBAL))
+ return 0;
+
+ /*
+ * If this is an instance, only create flags for tracers
+ * the instance may have.
+ */
+ if (!trace_ok_for_array(tracer, tr))
+ return 0;
+
+ t = kmalloc(sizeof(*t), GFP_KERNEL);
+ if (!t)
+ return -ENOMEM;
+
+ t->tracer = tracer;
+ t->flags = NULL;
+ list_add(&t->list, &tr->tracers);
+
+ flags = tracer->flags;
+ if (!flags) {
+ if (!tracer->default_flags)
+ return 0;
+
+ /*
+ * If the tracer defines default flags, it means the flags are
+ * per trace instance.
+ */
+ flags = kmalloc(sizeof(*flags), GFP_KERNEL);
+ if (!flags)
+ return -ENOMEM;
+
+ *flags = *tracer->default_flags;
+ flags->trace = tracer;
+
+ t->flags = flags;
+
+ /* If this is an instance, inherit the global_trace flags */
+ if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL)) {
+ int val = get_global_flags_val(tracer);
+ if (!WARN_ON_ONCE(val < 0))
+ flags->val = val;
+ }
+ }
+
+ ret = add_tracer_options(tr, t);
+ if (ret < 0) {
+ list_del(&t->list);
+ kfree(t->flags);
+ kfree(t);
+ }
+
+ return ret;
+}
+
static struct dentry *
create_trace_option_core_file(struct trace_array *tr,
const char *option, long index)
tr->trace_flags_index[i] = i;
}
-static int __update_tracer_options(struct trace_array *tr)
+static int __update_tracer(struct trace_array *tr)
{
struct tracer *t;
int ret = 0;
for (t = trace_types; t && !ret; t = t->next)
+ ret = add_tracer(tr, t);
+
+ return ret;
+}
+
+static __init int __update_tracer_options(struct trace_array *tr)
+{
+ struct tracers *t;
+ int ret = 0;
+
+ list_for_each_entry(t, &tr->tracers, list) {
ret = add_tracer_options(tr, t);
+ if (ret < 0)
+ break;
+ }
return ret;
}
}
init_tracer_tracefs(tr, tr->dir);
- ret = __update_tracer_options(tr);
+ ret = __update_tracer(tr);
if (ret) {
event_trace_del_tracer(tr);
tracefs_remove(tr->dir);
spin_lock_init(&tr->snapshot_trigger_lock);
#endif
tr->current_trace = &nop_trace;
+ tr->current_trace_flags = nop_trace.flags;
INIT_LIST_HEAD(&tr->systems);
INIT_LIST_HEAD(&tr->events);
INIT_LIST_HEAD(&tr->hist_vars);
INIT_LIST_HEAD(&tr->err_log);
+ INIT_LIST_HEAD(&tr->tracers);
INIT_LIST_HEAD(&tr->marker_list);
#ifdef CONFIG_MODULES
free_percpu(tr->last_func_repeats);
free_trace_buffers(tr);
clear_tracing_err_log(tr);
+ free_tracers(tr);
if (tr->range_name) {
reserve_mem_release_by_name(tr->range_name);
* just a bootstrap of current_trace anyway.
*/
global_trace.current_trace = &nop_trace;
+ global_trace.current_trace_flags = nop_trace.flags;
global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
#ifdef CONFIG_TRACER_MAX_TRACE
init_trace_flags_index(&global_trace);
- register_tracer(&nop_trace);
-
- /* Function tracing may start here (via kernel command line) */
- init_function_trace();
+ INIT_LIST_HEAD(&global_trace.tracers);
/* All seems OK, enable tracing */
tracing_disabled = 0;
list_add(&global_trace.marker_list, &marker_copies);
list_add(&global_trace.list, &ftrace_trace_arrays);
+ register_tracer(&nop_trace);
+
+ /* Function tracing may start here (via kernel command line) */
+ init_function_trace();
+
apply_trace_boot_options();
register_snapshot_cmd();
gentwo / linux / .git / commitdiff