tracing: Pass the trace_array into ftrace_probe_ops functions

Pass the trace_array associated to a ftrace_probe_ops into the probe_ops
func(), init() and free() functions. The trace_array is the descriptor that
describes a tracing instance. This will help create the infrastructure that
will allow having function probes unique to tracing instances.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

1 files changed, 9 insertions, 4 deletions

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index ea208e93f000..e51cd6b51253 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -3791,6 +3791,7 @@ static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip,
                                       struct ftrace_ops *op, struct pt_regs *pt_regs)
 {
         struct ftrace_probe_ops *probe_ops;
+        struct trace_array *tr = op->private;
 
         probe_ops = container_of(op, struct ftrace_probe_ops, ops);
 
@@ -3800,7 +3801,7 @@ static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip,
          * on the hash. rcu_read_lock is too dangerous here.
          */
         preempt_disable_notrace();
-        probe_ops->func(ip, parent_ip, probe_ops, NULL);
+        probe_ops->func(ip, parent_ip, tr, probe_ops, NULL);
         preempt_enable_notrace();
 }
 
@@ -3969,6 +3970,7 @@ register_ftrace_function_probe(char *glob, struct trace_array *tr,
                 ops->ops.func = function_trace_probe_call;
                 ftrace_ops_init(&ops->ops);
                 INIT_LIST_HEAD(&ops->list);
+                ops->ops.private = tr;
         }
 
         mutex_lock(&ops->ops.func_hash->regex_lock);
@@ -3997,7 +3999,7 @@ register_ftrace_function_probe(char *glob, struct trace_array *tr,
                          * to give the caller an opportunity to do so.
                          */
                         if (ops->init) {
-                                ret = ops->init(ops, entry->ip, data);
+                                ret = ops->init(ops, tr, entry->ip, data);
                                 if (ret < 0)
                                         goto out;
                         }
@@ -4038,7 +4040,7 @@ register_ftrace_function_probe(char *glob, struct trace_array *tr,
                 hlist_for_each_entry(entry, &hash->buckets[i], hlist) {
                         if (ftrace_lookup_ip(old_hash, entry->ip))
                                 continue;
-                        ops->free(ops, entry->ip, NULL);
+                        ops->free(ops, tr, entry->ip, NULL);
                 }
         }
         goto out_unlock;
@@ -4055,6 +4057,7 @@ unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops)
         struct ftrace_hash *hash = NULL;
         struct hlist_node *tmp;
         struct hlist_head hhd;
+        struct trace_array *tr;
         char str[KSYM_SYMBOL_LEN];
         int i, ret;
         int size;
@@ -4062,6 +4065,8 @@ unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops)
         if (!(ops->ops.flags & FTRACE_OPS_FL_INITIALIZED))
                 return -EINVAL;
 
+        tr = ops->ops.private;
+
         if (glob && (strcmp(glob, "*") == 0 || !strlen(glob)))
                 func_g.search = NULL;
         else if (glob) {
@@ -4139,7 +4144,7 @@ unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops)
         hlist_for_each_entry_safe(entry, tmp, &hhd, hlist) {
                 hlist_del(&entry->hlist);
                 if (ops->free)
-                        ops->free(ops, entry->ip, NULL);
+                        ops->free(ops, tr, entry->ip, NULL);
                 kfree(entry);
         }
         mutex_unlock(&ftrace_lock);