ftrace: Replace uses of _ftrace_direct APIs with _ftrace_direct_multi

JIRA: https://issues.redhat.com/browse/RHEL-101598

commit 23edf48
Author: Florent Revest <[email protected]>
Date:   Tue Mar 21 15:04:19 2023 +0100

    ftrace: Replace uses of _ftrace_direct APIs with _ftrace_direct_multi

    The _multi API requires that users keep their own ops but can enforce
    that an op is only associated to one direct call.

    Link: https://lkml.kernel.org/r/[email protected]

    Signed-off-by: Florent Revest <[email protected]>
    Acked-by: Mark Rutland <[email protected]>
    Tested-by: Mark Rutland <[email protected]>
    Acked-by: Jiri Olsa <[email protected]>
    Signed-off-by: Steven Rostedt (Google) <[email protected]>

Conflicts:
- kernel/trace/trace_selftest.c: 2 hunks modified due to already backported
fee86a4 ("ftrace: selftest: remove broken trace_direct_tramp")

Assisted-by: Patchpal AI
Signed-off-by: Jerome Marchand <[email protected]>

Author: jeromemarchand

kernel/trace/trace_selftest.c

@@ -810,6 +810,7 @@ trace_selftest_startup_function_graph(struct tracer *trace,
 	}
 
 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+static struct ftrace_ops direct;
 	tracing_reset_online_cpus(&tr->array_buffer);
 	set_graph_array(tr);
 
@@ -825,8 +826,8 @@ trace_selftest_startup_function_graph(struct tracer *trace,
 	 * Register direct function together with graph tracer
 	 * and make sure we get graph trace.
 	 */
-	ret = register_ftrace_direct((unsigned long) DYN_FTRACE_TEST_NAME,
-				     (unsigned long)ftrace_stub_direct_tramp);
+	ftrace_set_filter_ip(&direct, (unsigned long)DYN_FTRACE_TEST_NAME, 0, 0);
+	ret = register_ftrace_direct_multi(&direct, (unsigned long)ftrace_stub_direct_tramp);
 	if (ret)
 		goto out;
 
@@ -846,8 +847,9 @@ trace_selftest_startup_function_graph(struct tracer *trace,
 
 	unregister_ftrace_graph(&fgraph_ops);
 
-	ret = unregister_ftrace_direct((unsigned long) DYN_FTRACE_TEST_NAME,
-				       (unsigned long)ftrace_stub_direct_tramp);
+	ret = unregister_ftrace_direct_multi(&direct,
+					     (unsigned long)ftrace_stub_direct_tramp,
+					     true);
 	if (ret)
 		goto out;
 

samples/ftrace/ftrace-direct-modify.c

@@ -96,6 +96,8 @@ asm (
 
 #endif /* CONFIG_S390 */
 
+static struct ftrace_ops direct;
+
 static unsigned long my_tramp = (unsigned long)my_tramp1;
 static unsigned long tramps[2] = {
 	(unsigned long)my_tramp1,
@@ -114,7 +116,7 @@ static int simple_thread(void *arg)
 		if (ret)
 			continue;
 		t ^= 1;
-		ret = modify_ftrace_direct(my_ip, my_tramp, tramps[t]);
+		ret = modify_ftrace_direct_multi(&direct, tramps[t]);
 		if (!ret)
 			my_tramp = tramps[t];
 		WARN_ON_ONCE(ret);
@@ -129,7 +131,9 @@ static int __init ftrace_direct_init(void)
 {
 	int ret;
 
-	ret = register_ftrace_direct(my_ip, my_tramp);
+	ftrace_set_filter_ip(&direct, (unsigned long) my_ip, 0, 0);
+	ret = register_ftrace_direct_multi(&direct, my_tramp);
+
 	if (!ret)
 		simple_tsk = kthread_run(simple_thread, NULL, "event-sample-fn");
 	return ret;
@@ -138,12 +142,12 @@ static int __init ftrace_direct_init(void)
 static void __exit ftrace_direct_exit(void)
 {
 	kthread_stop(simple_tsk);
-	unregister_ftrace_direct(my_ip, my_tramp);
+	unregister_ftrace_direct_multi(&direct, my_tramp, true);
 }
 
 module_init(ftrace_direct_init);
 module_exit(ftrace_direct_exit);
 
 MODULE_AUTHOR("Steven Rostedt");
-MODULE_DESCRIPTION("Example use case of using modify_ftrace_direct()");
+MODULE_DESCRIPTION("Example use case of using modify_ftrace_direct_multi()");
 MODULE_LICENSE("GPL");

samples/ftrace/ftrace-direct-too.c

@@ -70,21 +70,23 @@ asm (
 
 #endif /* CONFIG_S390 */
 
+static struct ftrace_ops direct;
+
 static int __init ftrace_direct_init(void)
 {
-	return register_ftrace_direct((unsigned long)handle_mm_fault,
-				     (unsigned long)my_tramp);
+	ftrace_set_filter_ip(&direct, (unsigned long) handle_mm_fault, 0, 0);
+
+	return register_ftrace_direct_multi(&direct, (unsigned long) my_tramp);
 }
 
 static void __exit ftrace_direct_exit(void)
 {
-	unregister_ftrace_direct((unsigned long)handle_mm_fault,
-				 (unsigned long)my_tramp);
+	unregister_ftrace_direct_multi(&direct, (unsigned long)my_tramp, true);
 }
 
 module_init(ftrace_direct_init);
 module_exit(ftrace_direct_exit);
 
 MODULE_AUTHOR("Steven Rostedt");
-MODULE_DESCRIPTION("Another example use case of using register_ftrace_direct()");
+MODULE_DESCRIPTION("Another example use case of using register_ftrace_direct_multi()");
 MODULE_LICENSE("GPL");

samples/ftrace/ftrace-direct.c

@@ -63,21 +63,23 @@ asm (
 
 #endif /* CONFIG_S390 */
 
+static struct ftrace_ops direct;
+
 static int __init ftrace_direct_init(void)
 {
-	return register_ftrace_direct((unsigned long)wake_up_process,
-				     (unsigned long)my_tramp);
+	ftrace_set_filter_ip(&direct, (unsigned long) wake_up_process, 0, 0);
+
+	return register_ftrace_direct_multi(&direct, (unsigned long) my_tramp);
 }
 
 static void __exit ftrace_direct_exit(void)
 {
-	unregister_ftrace_direct((unsigned long)wake_up_process,
-				 (unsigned long)my_tramp);
+	unregister_ftrace_direct_multi(&direct, (unsigned long)my_tramp, true);
 }
 
 module_init(ftrace_direct_init);
 module_exit(ftrace_direct_exit);
 
 MODULE_AUTHOR("Steven Rostedt");
-MODULE_DESCRIPTION("Example use case of using register_ftrace_direct()");
+MODULE_DESCRIPTION("Example use case of using register_ftrace_direct_multi()");
 MODULE_LICENSE("GPL");