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-rw-r--r--kernel/trace/trace.c111
1 files changed, 73 insertions, 38 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 4c187740c0df..528971714fc6 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2650,7 +2650,7 @@ void trace_buffered_event_enable(void)
preempt_disable();
if (cpu == smp_processor_id() &&
- this_cpu_read(trace_buffered_event) !=
+ __this_cpu_read(trace_buffered_event) !=
per_cpu(trace_buffered_event, cpu))
WARN_ON_ONCE(1);
preempt_enable();
@@ -5142,10 +5142,10 @@ static const char readme_msg[] =
"\t -:[<group>/]<event>\n"
#ifdef CONFIG_KPROBE_EVENTS
"\t place: [<module>:]<symbol>[+<offset>]|<memaddr>\n"
- "place (kretprobe): [<module>:]<symbol>[+<offset>]|<memaddr>\n"
+ "place (kretprobe): [<module>:]<symbol>[+<offset>]%return|<memaddr>\n"
#endif
#ifdef CONFIG_UPROBE_EVENTS
- " place (uprobe): <path>:<offset>[(ref_ctr_offset)]\n"
+ " place (uprobe): <path>:<offset>[%return][(ref_ctr_offset)]\n"
#endif
"\t args: <name>=fetcharg[:type]\n"
"\t fetcharg: %<register>, @<address>, @<symbol>[+|-<offset>],\n"
@@ -5269,7 +5269,12 @@ static const char readme_msg[] =
"\t trace(<synthetic_event>,param list) - generate synthetic event\n"
"\t save(field,...) - save current event fields\n"
#ifdef CONFIG_TRACER_SNAPSHOT
- "\t snapshot() - snapshot the trace buffer\n"
+ "\t snapshot() - snapshot the trace buffer\n\n"
+#endif
+#ifdef CONFIG_SYNTH_EVENTS
+ " events/synthetic_events\t- Create/append/remove/show synthetic events\n"
+ "\t Write into this file to define/undefine new synthetic events.\n"
+ "\t example: echo 'myevent u64 lat; char name[]' >> synthetic_events\n"
#endif
#endif
;
@@ -6682,7 +6687,6 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
written = -EFAULT;
} else
written = cnt;
- len = cnt;
if (tr->trace_marker_file && !list_empty(&tr->trace_marker_file->triggers)) {
/* do not add \n before testing triggers, but add \0 */
@@ -8658,6 +8662,24 @@ struct trace_array *trace_array_find_get(const char *instance)
return tr;
}
+static int trace_array_create_dir(struct trace_array *tr)
+{
+ int ret;
+
+ tr->dir = tracefs_create_dir(tr->name, trace_instance_dir);
+ if (!tr->dir)
+ return -EINVAL;
+
+ ret = event_trace_add_tracer(tr->dir, tr);
+ if (ret)
+ tracefs_remove(tr->dir);
+
+ init_tracer_tracefs(tr, tr->dir);
+ __update_tracer_options(tr);
+
+ return ret;
+}
+
static struct trace_array *trace_array_create(const char *name)
{
struct trace_array *tr;
@@ -8693,30 +8715,28 @@ static struct trace_array *trace_array_create(const char *name)
if (allocate_trace_buffers(tr, trace_buf_size) < 0)
goto out_free_tr;
- tr->dir = tracefs_create_dir(name, trace_instance_dir);
- if (!tr->dir)
+ if (ftrace_allocate_ftrace_ops(tr) < 0)
goto out_free_tr;
- ret = event_trace_add_tracer(tr->dir, tr);
- if (ret) {
- tracefs_remove(tr->dir);
- goto out_free_tr;
- }
-
ftrace_init_trace_array(tr);
- init_tracer_tracefs(tr, tr->dir);
init_trace_flags_index(tr);
- __update_tracer_options(tr);
+
+ if (trace_instance_dir) {
+ ret = trace_array_create_dir(tr);
+ if (ret)
+ goto out_free_tr;
+ } else
+ __trace_early_add_events(tr);
list_add(&tr->list, &ftrace_trace_arrays);
tr->ref++;
-
return tr;
out_free_tr:
+ ftrace_free_ftrace_ops(tr);
free_trace_buffers(tr);
free_cpumask_var(tr->tracing_cpumask);
kfree(tr->name);
@@ -8821,7 +8841,6 @@ static int __remove_instance(struct trace_array *tr)
free_cpumask_var(tr->tracing_cpumask);
kfree(tr->name);
kfree(tr);
- tr = NULL;
return 0;
}
@@ -8875,11 +8894,27 @@ static int instance_rmdir(const char *name)
static __init void create_trace_instances(struct dentry *d_tracer)
{
+ struct trace_array *tr;
+
trace_instance_dir = tracefs_create_instance_dir("instances", d_tracer,
instance_mkdir,
instance_rmdir);
if (MEM_FAIL(!trace_instance_dir, "Failed to create instances directory\n"))
return;
+
+ mutex_lock(&event_mutex);
+ mutex_lock(&trace_types_lock);
+
+ list_for_each_entry(tr, &ftrace_trace_arrays, list) {
+ if (!tr->name)
+ continue;
+ if (MEM_FAIL(trace_array_create_dir(tr) < 0,
+ "Failed to create instance directory\n"))
+ break;
+ }
+
+ mutex_unlock(&trace_types_lock);
+ mutex_unlock(&event_mutex);
}
static void
@@ -8993,21 +9028,21 @@ static struct vfsmount *trace_automount(struct dentry *mntpt, void *ingore)
* directory. It is called via fs_initcall() by any of the boot up code
* and expects to return the dentry of the top level tracing directory.
*/
-struct dentry *tracing_init_dentry(void)
+int tracing_init_dentry(void)
{
struct trace_array *tr = &global_trace;
if (security_locked_down(LOCKDOWN_TRACEFS)) {
pr_warn("Tracing disabled due to lockdown\n");
- return ERR_PTR(-EPERM);
+ return -EPERM;
}
/* The top level trace array uses NULL as parent */
if (tr->dir)
- return NULL;
+ return 0;
if (WARN_ON(!tracefs_initialized()))
- return ERR_PTR(-ENODEV);
+ return -ENODEV;
/*
* As there may still be users that expect the tracing
@@ -9018,7 +9053,7 @@ struct dentry *tracing_init_dentry(void)
tr->dir = debugfs_create_automount("tracing", NULL,
trace_automount, NULL);
- return NULL;
+ return 0;
}
extern struct trace_eval_map *__start_ftrace_eval_maps[];
@@ -9105,48 +9140,48 @@ static struct notifier_block trace_module_nb = {
static __init int tracer_init_tracefs(void)
{
- struct dentry *d_tracer;
+ int ret;
trace_access_lock_init();
- d_tracer = tracing_init_dentry();
- if (IS_ERR(d_tracer))
+ ret = tracing_init_dentry();
+ if (ret)
return 0;
event_trace_init();
- init_tracer_tracefs(&global_trace, d_tracer);
- ftrace_init_tracefs_toplevel(&global_trace, d_tracer);
+ init_tracer_tracefs(&global_trace, NULL);
+ ftrace_init_tracefs_toplevel(&global_trace, NULL);
- trace_create_file("tracing_thresh", 0644, d_tracer,
+ trace_create_file("tracing_thresh", 0644, NULL,
&global_trace, &tracing_thresh_fops);
- trace_create_file("README", 0444, d_tracer,
+ trace_create_file("README", 0444, NULL,
NULL, &tracing_readme_fops);
- trace_create_file("saved_cmdlines", 0444, d_tracer,
+ trace_create_file("saved_cmdlines", 0444, NULL,
NULL, &tracing_saved_cmdlines_fops);
- trace_create_file("saved_cmdlines_size", 0644, d_tracer,
+ trace_create_file("saved_cmdlines_size", 0644, NULL,
NULL, &tracing_saved_cmdlines_size_fops);
- trace_create_file("saved_tgids", 0444, d_tracer,
+ trace_create_file("saved_tgids", 0444, NULL,
NULL, &tracing_saved_tgids_fops);
trace_eval_init();
- trace_create_eval_file(d_tracer);
+ trace_create_eval_file(NULL);
#ifdef CONFIG_MODULES
register_module_notifier(&trace_module_nb);
#endif
#ifdef CONFIG_DYNAMIC_FTRACE
- trace_create_file("dyn_ftrace_total_info", 0444, d_tracer,
+ trace_create_file("dyn_ftrace_total_info", 0444, NULL,
NULL, &tracing_dyn_info_fops);
#endif
- create_trace_instances(d_tracer);
+ create_trace_instances(NULL);
update_tracer_options(&global_trace);
@@ -9309,7 +9344,7 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
}
/*
- * We need to stop all tracing on all CPUS to read the
+ * We need to stop all tracing on all CPUS to read
* the next buffer. This is a bit expensive, but is
* not done often. We fill all what we can read,
* and then release the locks again.
@@ -9452,7 +9487,7 @@ __init static int tracer_alloc_buffers(void)
}
/*
- * Make sure we don't accidently add more trace options
+ * Make sure we don't accidentally add more trace options
* than we have bits for.
*/
BUILD_BUG_ON(TRACE_ITER_LAST_BIT > TRACE_FLAGS_MAX_SIZE);
@@ -9481,7 +9516,7 @@ __init static int tracer_alloc_buffers(void)
/*
* The prepare callbacks allocates some memory for the ring buffer. We
- * don't free the buffer if the if the CPU goes down. If we were to free
+ * don't free the buffer if the CPU goes down. If we were to free
* the buffer, then the user would lose any trace that was in the
* buffer. The memory will be removed once the "instance" is removed.
*/
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.