[PATCH 2/7] ftrace: Replace uses of _ftrace_direct APIs with _ftrace_direct_multi

Florent Revest
2023-03-16T17:38:43Z

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

Signed-off-by: Florent Revest <revest@chromium.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
---
kernel/trace/trace_selftest.c | 10 ++++++----
samples/ftrace/ftrace-direct-modify.c | 12 ++++++++----
samples/ftrace/ftrace-direct-too.c | 12 +++++++-----
samples/ftrace/ftrace-direct.c | 12 +++++++-----
4 files changed, 28 insertions(+), 18 deletions(-)

diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index ff0536cea968..9ce80b3ad06d 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -785,6 +785,7 @@ static struct fgraph_ops fgraph_ops __initdata = {
};

#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+static struct ftrace_ops direct;
#ifndef CALL_DEPTH_ACCOUNT
#define CALL_DEPTH_ACCOUNT ""
#endif
@@ -870,8 +871,8 @@ 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) trace_direct_tramp);
+ ftrace_set_filter_ip(&direct, (unsigned long)DYN_FTRACE_TEST_NAME, 0, 0);
+ ret = register_ftrace_direct_multi(&direct, (unsigned long)trace_direct_tramp);
if (ret)
goto out;

@@ -891,8 +892,9 @@ 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) trace_direct_tramp);
+ ret = unregister_ftrace_direct_multi(&direct,
+ (unsigned long) trace_direct_tramp,
+ true);
if (ret)
goto out;

diff --git a/samples/ftrace/ftrace-direct-modify.c b/samples/ftrace/ftrace-direct-modify.c
index d93abbcb1f4c..f01ac74bac10 100644
--- a/samples/ftrace/ftrace-direct-modify.c
+++ b/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");
diff --git a/samples/ftrace/ftrace-direct-too.c b/samples/ftrace/ftrace-direct-too.c
index 8139dce2a31c..05c3585ac15e 100644
--- a/samples/ftrace/ftrace-direct-too.c
+++ b/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");
diff --git a/samples/ftrace/ftrace-direct.c b/samples/ftrace/ftrace-direct.c
index 1d3d307ca33d..42ec9e39453b 100644
--- a/samples/ftrace/ftrace-direct.c
+++ b/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");
--
2.40.0.rc2.332.ga46443480c-goog