Re: [PATCH 3/8] ftrace: Rename _ftrace_direct_multi APIs to _ftrace_direct APIs

Mark Rutland
2023-02-02T15:18:38Z

On Wed, Feb 01, 2023 at 05:34:15PM +0100, Florent Revest wrote:
> Now that the original _ftrace_direct APIs are gone, the "_multi"
> suffixes only add confusion.
>
> Signed-off-by: Florent Revest <revest@chromium.org>
> ---
> include/linux/ftrace.h | 16 +++++------
> kernel/bpf/trampoline.c | 14 ++++-----
> kernel/trace/ftrace.c | 32 ++++++++++-----------
> kernel/trace/trace_selftest.c | 7 +++--
> samples/Kconfig | 2 +-
> samples/ftrace/ftrace-direct-modify.c | 8 +++---
> samples/ftrace/ftrace-direct-multi-modify.c | 8 +++---
> samples/ftrace/ftrace-direct-multi.c | 6 ++--
> samples/ftrace/ftrace-direct-too.c | 6 ++--
> samples/ftrace/ftrace-direct.c | 6 ++--
> 10 files changed, 53 insertions(+), 52 deletions(-)

This looks like a sensible cleanup to me.

As with the last two patches, on x86_64 the kernel builds cleanly, the
FTRACE_STARTUP_TEST is happy, and loading each of the ftrace_direct*.ko samples
works fine. So:

Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>

Thanks,
Mark.

> diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
> index 2d7c85e47c2d..a7dbd307c3a4 100644
> --- a/include/linux/ftrace.h
> +++ b/include/linux/ftrace.h
> @@ -398,10 +398,10 @@ struct ftrace_func_entry {
> #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
> extern int ftrace_direct_func_count;
> unsigned long ftrace_find_rec_direct(unsigned long ip);
> -int register_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr);
> -int unregister_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr);
> -int modify_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr);
> -int modify_ftrace_direct_multi_nolock(struct ftrace_ops *ops, unsigned long addr);
> +int register_ftrace_direct(struct ftrace_ops *ops, unsigned long addr);
> +int unregister_ftrace_direct(struct ftrace_ops *ops, unsigned long addr);
> +int modify_ftrace_direct(struct ftrace_ops *ops, unsigned long addr);
> +int modify_ftrace_direct_nolock(struct ftrace_ops *ops, unsigned long addr);
>
> #else
> struct ftrace_ops;
> @@ -410,19 +410,19 @@ static inline unsigned long ftrace_find_rec_direct(unsigned long ip)
> {
> return 0;
> }
> -static inline int register_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)
> +static inline int register_ftrace_direct(struct ftrace_ops *ops, unsigned long addr)
> {
> return -ENODEV;
> }
> -static inline int unregister_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)
> +static inline int unregister_ftrace_direct(struct ftrace_ops *ops, unsigned long addr)
> {
> return -ENODEV;
> }
> -static inline int modify_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)
> +static inline int modify_ftrace_direct(struct ftrace_ops *ops, unsigned long addr)
> {
> return -ENODEV;
> }
> -static inline int modify_ftrace_direct_multi_nolock(struct ftrace_ops *ops, unsigned long addr)
> +static inline int modify_ftrace_direct_nolock(struct ftrace_ops *ops, unsigned long addr)
> {
> return -ENODEV;
> }
> diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
> index d0ed7d6f5eec..150b53316df2 100644
> --- a/kernel/bpf/trampoline.c
> +++ b/kernel/bpf/trampoline.c
> @@ -39,14 +39,14 @@ static int bpf_tramp_ftrace_ops_func(struct ftrace_ops *ops, enum ftrace_ops_cmd
> int ret = 0;
>
> if (cmd == FTRACE_OPS_CMD_ENABLE_SHARE_IPMODIFY_SELF) {
> - /* This is called inside register_ftrace_direct_multi(), so
> + /* This is called inside register_ftrace_direct(), so
> * tr->mutex is already locked.
> */
> lockdep_assert_held_once(&tr->mutex);
>
> /* Instead of updating the trampoline here, we propagate
> - * -EAGAIN to register_ftrace_direct_multi(). Then we can
> - * retry register_ftrace_direct_multi() after updating the
> + * -EAGAIN to register_ftrace_direct(). Then we can
> + * retry register_ftrace_direct() after updating the
> * trampoline.
> */
> if ((tr->flags & BPF_TRAMP_F_CALL_ORIG) &&
> @@ -198,7 +198,7 @@ static int unregister_fentry(struct bpf_trampoline *tr, void *old_addr)
> int ret;
>
> if (tr->func.ftrace_managed)
> - ret = unregister_ftrace_direct_multi(tr->fops, (long)old_addr);
> + ret = unregister_ftrace_direct(tr->fops, (long)old_addr);
> else
> ret = bpf_arch_text_poke(ip, BPF_MOD_CALL, old_addr, NULL);
>
> @@ -215,9 +215,9 @@ static int modify_fentry(struct bpf_trampoline *tr, void *old_addr, void *new_ad
>
> if (tr->func.ftrace_managed) {
> if (lock_direct_mutex)
> - ret = modify_ftrace_direct_multi(tr->fops, (long)new_addr);
> + ret = modify_ftrace_direct(tr->fops, (long)new_addr);
> else
> - ret = modify_ftrace_direct_multi_nolock(tr->fops, (long)new_addr);
> + ret = modify_ftrace_direct_nolock(tr->fops, (long)new_addr);
> } else {
> ret = bpf_arch_text_poke(ip, BPF_MOD_CALL, old_addr, new_addr);
> }
> @@ -243,7 +243,7 @@ static int register_fentry(struct bpf_trampoline *tr, void *new_addr)
>
> if (tr->func.ftrace_managed) {
> ftrace_set_filter_ip(tr->fops, (unsigned long)ip, 0, 1);
> - ret = register_ftrace_direct_multi(tr->fops, (long)new_addr);
> + ret = register_ftrace_direct(tr->fops, (long)new_addr);
> } else {
> ret = bpf_arch_text_poke(ip, BPF_MOD_CALL, NULL, new_addr);
> }
> diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
> index 5efe201428fa..cb77a0a208c7 100644
> --- a/kernel/trace/ftrace.c
> +++ b/kernel/trace/ftrace.c
> @@ -5312,7 +5312,7 @@ static void remove_direct_functions_hash(struct ftrace_hash *hash, unsigned long
> }
>
> /**
> - * register_ftrace_direct_multi - Call a custom trampoline directly
> + * register_ftrace_direct - Call a custom trampoline directly
> * for multiple functions registered in @ops
> * @ops: The address of the struct ftrace_ops object
> * @addr: The address of the trampoline to call at @ops functions
> @@ -5333,7 +5333,7 @@ static void remove_direct_functions_hash(struct ftrace_hash *hash, unsigned long
> * -ENODEV - @ip does not point to a ftrace nop location (or not supported)
> * -ENOMEM - There was an allocation failure.
> */
> -int register_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)
> +int register_ftrace_direct(struct ftrace_ops *ops, unsigned long addr)
> {
> struct ftrace_hash *hash, *free_hash = NULL;
> struct ftrace_func_entry *entry, *new;
> @@ -5391,11 +5391,11 @@ int register_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)
> }
> return err;
> }
> -EXPORT_SYMBOL_GPL(register_ftrace_direct_multi);
> +EXPORT_SYMBOL_GPL(register_ftrace_direct);
>
> /**
> - * unregister_ftrace_direct_multi - Remove calls to custom trampoline
> - * previously registered by register_ftrace_direct_multi for @ops object.
> + * unregister_ftrace_direct - Remove calls to custom trampoline
> + * previously registered by register_ftrace_direct for @ops object.
> * @ops: The address of the struct ftrace_ops object
> *
> * This is used to remove a direct calls to @addr from the nop locations
> @@ -5406,7 +5406,7 @@ EXPORT_SYMBOL_GPL(register_ftrace_direct_multi);
> * 0 on success
> * -EINVAL - The @ops object was not properly registered.
> */
> -int unregister_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)
> +int unregister_ftrace_direct(struct ftrace_ops *ops, unsigned long addr)
> {
> struct ftrace_hash *hash = ops->func_hash->filter_hash;
> int err;
> @@ -5426,10 +5426,10 @@ int unregister_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)
> ops->trampoline = 0;
> return err;
> }
> -EXPORT_SYMBOL_GPL(unregister_ftrace_direct_multi);
> +EXPORT_SYMBOL_GPL(unregister_ftrace_direct);
>
> static int
> -__modify_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)
> +__modify_ftrace_direct(struct ftrace_ops *ops, unsigned long addr)
> {
> struct ftrace_hash *hash;
> struct ftrace_func_entry *entry, *iter;
> @@ -5476,7 +5476,7 @@ __modify_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)
> }
>
> /**
> - * modify_ftrace_direct_multi_nolock - Modify an existing direct 'multi' call
> + * modify_ftrace_direct_nolock - Modify an existing direct 'multi' call
> * to call something else
> * @ops: The address of the struct ftrace_ops object
> * @addr: The address of the new trampoline to call at @ops functions
> @@ -5493,19 +5493,19 @@ __modify_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)
> * Returns: zero on success. Non zero on error, which includes:
> * -EINVAL - The @ops object was not properly registered.
> */
> -int modify_ftrace_direct_multi_nolock(struct ftrace_ops *ops, unsigned long addr)
> +int modify_ftrace_direct_nolock(struct ftrace_ops *ops, unsigned long addr)
> {
> if (check_direct_multi(ops))
> return -EINVAL;
> if (!(ops->flags & FTRACE_OPS_FL_ENABLED))
> return -EINVAL;
>
> - return __modify_ftrace_direct_multi(ops, addr);
> + return __modify_ftrace_direct(ops, addr);
> }
> -EXPORT_SYMBOL_GPL(modify_ftrace_direct_multi_nolock);
> +EXPORT_SYMBOL_GPL(modify_ftrace_direct_nolock);
>
> /**
> - * modify_ftrace_direct_multi - Modify an existing direct 'multi' call
> + * modify_ftrace_direct - Modify an existing direct 'multi' call
> * to call something else
> * @ops: The address of the struct ftrace_ops object
> * @addr: The address of the new trampoline to call at @ops functions
> @@ -5519,7 +5519,7 @@ EXPORT_SYMBOL_GPL(modify_ftrace_direct_multi_nolock);
> * Returns: zero on success. Non zero on error, which includes:
> * -EINVAL - The @ops object was not properly registered.
> */
> -int modify_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)
> +int modify_ftrace_direct(struct ftrace_ops *ops, unsigned long addr)
> {
> int err;
>
> @@ -5529,11 +5529,11 @@ int modify_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)
> return -EINVAL;
>
> mutex_lock(&direct_mutex);
> - err = __modify_ftrace_direct_multi(ops, addr);
> + err = __modify_ftrace_direct(ops, addr);
> mutex_unlock(&direct_mutex);
> return err;
> }
> -EXPORT_SYMBOL_GPL(modify_ftrace_direct_multi);
> +EXPORT_SYMBOL_GPL(modify_ftrace_direct);
> #endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */
>
> /**
> diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
> index 9b7f10cbc51d..06218fc9374b 100644
> --- a/kernel/trace/trace_selftest.c
> +++ b/kernel/trace/trace_selftest.c
> @@ -874,7 +874,8 @@ trace_selftest_startup_function_graph(struct tracer *trace,
> * and make sure we get graph trace.
> */
> ftrace_set_filter_ip(&direct, (unsigned long)DYN_FTRACE_TEST_NAME, 0, 0);
> - ret = register_ftrace_direct_multi(&direct, (unsigned long)trace_direct_tramp);
> + ret = register_ftrace_direct(&direct,
> + (unsigned long)trace_direct_tramp);
> if (ret)
> goto out;
>
> @@ -894,8 +895,8 @@ trace_selftest_startup_function_graph(struct tracer *trace,
>
> unregister_ftrace_graph(&fgraph_ops);
>
> - ret = unregister_ftrace_direct_multi(&direct,
> - (unsigned long) trace_direct_tramp);
> + ret = unregister_ftrace_direct(&direct,
> + (unsigned long)trace_direct_tramp);
> if (ret)
> goto out;
>
> diff --git a/samples/Kconfig b/samples/Kconfig
> index 0d81c00289ee..e85998ca354d 100644
> --- a/samples/Kconfig
> +++ b/samples/Kconfig
> @@ -38,7 +38,7 @@ config SAMPLE_FTRACE_DIRECT
> that hooks to wake_up_process and prints the parameters.
>
> config SAMPLE_FTRACE_DIRECT_MULTI
> - tristate "Build register_ftrace_direct_multi() example"
> + tristate "Build register_ftrace_direct() on multiple ips example"
> depends on DYNAMIC_FTRACE_WITH_DIRECT_CALLS && m
> depends on HAVE_SAMPLE_FTRACE_DIRECT_MULTI
> help
> diff --git a/samples/ftrace/ftrace-direct-modify.c b/samples/ftrace/ftrace-direct-modify.c
> index e1e6c286970c..0f1b8859e1e1 100644
> --- a/samples/ftrace/ftrace-direct-modify.c
> +++ b/samples/ftrace/ftrace-direct-modify.c
> @@ -116,7 +116,7 @@ static int simple_thread(void *arg)
> if (ret)
> continue;
> t ^= 1;
> - ret = modify_ftrace_direct_multi(&direct, tramps[t]);
> + ret = modify_ftrace_direct(&direct, tramps[t]);
> if (!ret)
> my_tramp = tramps[t];
> WARN_ON_ONCE(ret);
> @@ -132,7 +132,7 @@ static int __init ftrace_direct_init(void)
> int ret;
>
> ftrace_set_filter_ip(&direct, (unsigned long) my_ip, 0, 0);
> - ret = register_ftrace_direct_multi(&direct, my_tramp);
> + ret = register_ftrace_direct(&direct, my_tramp);
> if (!ret)
> simple_tsk = kthread_run(simple_thread, NULL, "event-sample-fn");
> return ret;
> @@ -141,12 +141,12 @@ static int __init ftrace_direct_init(void)
> static void __exit ftrace_direct_exit(void)
> {
> kthread_stop(simple_tsk);
> - unregister_ftrace_direct_multi(&direct, my_tramp);
> + unregister_ftrace_direct(&direct, my_tramp);
> }
>
> module_init(ftrace_direct_init);
> module_exit(ftrace_direct_exit);
>
> MODULE_AUTHOR("Steven Rostedt");
> -MODULE_DESCRIPTION("Example use case of using modify_ftrace_direct_multi()");
> +MODULE_DESCRIPTION("Example use case of using modify_ftrace_direct()");
> MODULE_LICENSE("GPL");
> diff --git a/samples/ftrace/ftrace-direct-multi-modify.c b/samples/ftrace/ftrace-direct-multi-modify.c
> index d52370cad0b6..407c56325e65 100644
> --- a/samples/ftrace/ftrace-direct-multi-modify.c
> +++ b/samples/ftrace/ftrace-direct-multi-modify.c
> @@ -123,7 +123,7 @@ static int simple_thread(void *arg)
> if (ret)
> continue;
> t ^= 1;
> - ret = modify_ftrace_direct_multi(&direct, tramps[t]);
> + ret = modify_ftrace_direct(&direct, tramps[t]);
> if (!ret)
> my_tramp = tramps[t];
> WARN_ON_ONCE(ret);
> @@ -141,7 +141,7 @@ static int __init ftrace_direct_multi_init(void)
> ftrace_set_filter_ip(&direct, (unsigned long) wake_up_process, 0, 0);
> ftrace_set_filter_ip(&direct, (unsigned long) schedule, 0, 0);
>
> - ret = register_ftrace_direct_multi(&direct, my_tramp);
> + ret = register_ftrace_direct(&direct, my_tramp);
>
> if (!ret)
> simple_tsk = kthread_run(simple_thread, NULL, "event-sample-fn");
> @@ -151,12 +151,12 @@ static int __init ftrace_direct_multi_init(void)
> static void __exit ftrace_direct_multi_exit(void)
> {
> kthread_stop(simple_tsk);
> - unregister_ftrace_direct_multi(&direct, my_tramp);
> + unregister_ftrace_direct(&direct, my_tramp);
> }
>
> module_init(ftrace_direct_multi_init);
> module_exit(ftrace_direct_multi_exit);
>
> MODULE_AUTHOR("Jiri Olsa");
> -MODULE_DESCRIPTION("Example use case of using modify_ftrace_direct_multi()");
> +MODULE_DESCRIPTION("Example use case of using modify_ftrace_direct()");
> MODULE_LICENSE("GPL");
> diff --git a/samples/ftrace/ftrace-direct-multi.c b/samples/ftrace/ftrace-direct-multi.c
> index ec1088922517..42a94806a446 100644
> --- a/samples/ftrace/ftrace-direct-multi.c
> +++ b/samples/ftrace/ftrace-direct-multi.c
> @@ -73,17 +73,17 @@ static int __init ftrace_direct_multi_init(void)
> ftrace_set_filter_ip(&direct, (unsigned long) wake_up_process, 0, 0);
> ftrace_set_filter_ip(&direct, (unsigned long) schedule, 0, 0);
>
> - return register_ftrace_direct_multi(&direct, (unsigned long) my_tramp);
> + return register_ftrace_direct(&direct, (unsigned long) my_tramp);
> }
>
> static void __exit ftrace_direct_multi_exit(void)
> {
> - unregister_ftrace_direct_multi(&direct, (unsigned long) my_tramp);
> + unregister_ftrace_direct(&direct, (unsigned long) my_tramp);
> }
>
> module_init(ftrace_direct_multi_init);
> module_exit(ftrace_direct_multi_exit);
>
> MODULE_AUTHOR("Jiri Olsa");
> -MODULE_DESCRIPTION("Example use case of using register_ftrace_direct_multi()");
> +MODULE_DESCRIPTION("Example use case of using register_ftrace_direct()");
> MODULE_LICENSE("GPL");
> diff --git a/samples/ftrace/ftrace-direct-too.c b/samples/ftrace/ftrace-direct-too.c
> index 0e907092e2c0..7ee5dd3cc61d 100644
> --- a/samples/ftrace/ftrace-direct-too.c
> +++ b/samples/ftrace/ftrace-direct-too.c
> @@ -76,17 +76,17 @@ static int __init ftrace_direct_init(void)
> {
> ftrace_set_filter_ip(&direct, (unsigned long) handle_mm_fault, 0, 0);
>
> - return register_ftrace_direct_multi(&direct, (unsigned long) my_tramp);
> + return register_ftrace_direct(&direct, (unsigned long) my_tramp);
> }
>
> static void __exit ftrace_direct_exit(void)
> {
> - unregister_ftrace_direct_multi(&direct, (unsigned long)my_tramp);
> + unregister_ftrace_direct(&direct, (unsigned long)my_tramp);
> }
>
> 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_multi()");
> +MODULE_DESCRIPTION("Another example use case of using register_ftrace_direct()");
> MODULE_LICENSE("GPL");
> diff --git a/samples/ftrace/ftrace-direct.c b/samples/ftrace/ftrace-direct.c
> index e446c38f6b58..5ffce87fa83e 100644
> --- a/samples/ftrace/ftrace-direct.c
> +++ b/samples/ftrace/ftrace-direct.c
> @@ -69,17 +69,17 @@ static int __init ftrace_direct_init(void)
> {
> ftrace_set_filter_ip(&direct, (unsigned long) wake_up_process, 0, 0);
>
> - return register_ftrace_direct_multi(&direct, (unsigned long) my_tramp);
> + return register_ftrace_direct(&direct, (unsigned long) my_tramp);
> }
>
> static void __exit ftrace_direct_exit(void)
> {
> - unregister_ftrace_direct_multi(&direct, (unsigned long)my_tramp);
> + unregister_ftrace_direct(&direct, (unsigned long)my_tramp);
> }
>
> module_init(ftrace_direct_init);
> module_exit(ftrace_direct_exit);
>
> MODULE_AUTHOR("Steven Rostedt");
> -MODULE_DESCRIPTION("Example use case of using register_ftrace_direct_multi()");
> +MODULE_DESCRIPTION("Example use case of using register_ftrace_direct()");
> MODULE_LICENSE("GPL");
> --
> 2.39.1.519.gcb327c4b5f-goog