[PATCH] s390: remove useless preempt_(dis/en)able calls in ftrace code

[PATCH] s390: remove useless preempt_(dis/en)able calls in ftrace code

[Wander Lairson Costa]

Commit ce5e48036c9e("ftrace: disable preemption when recursion locked")
moved the preempt disabling/enabling code to
ftrace_test_recursion_trylock() and ftrace_test_recursion_unlock(), and
cleaned up all direct calls in the ftrace code. But it left s390 behind.

Signed-off-by: Wander Lairson Costa <wander@redhat.com>
---
 arch/s390/kernel/ftrace.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/arch/s390/kernel/ftrace.c b/arch/s390/kernel/ftrace.c
index 5510c7d10ddc..21d62d8b6b9a 100644
--- a/arch/s390/kernel/ftrace.c
+++ b/arch/s390/kernel/ftrace.c
@@ -290,7 +290,6 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
 		return;
 
 	regs = ftrace_get_regs(fregs);
-	preempt_disable_notrace();
 	p = get_kprobe((kprobe_opcode_t *)ip);
 	if (unlikely(!p) || kprobe_disabled(p))
 		goto out;
@@ -318,7 +317,6 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
 	}
 	__this_cpu_write(current_kprobe, NULL);
 out:
-	preempt_enable_notrace();
 	ftrace_test_recursion_unlock(bit);
 }
 NOKPROBE_SYMBOL(kprobe_ftrace_handler);
-- 
2.27.0

Re: [PATCH] s390: remove useless preempt_(dis/en)able calls in ftrace code

[Heiko Carstens]

On Wed, Dec 08, 2021 at 01:27:19PM -0300, Wander Lairson Costa wrote:
> Commit ce5e48036c9e("ftrace: disable preemption when recursion locked")
> moved the preempt disabling/enabling code to
> ftrace_test_recursion_trylock() and ftrace_test_recursion_unlock(), and
> cleaned up all direct calls in the ftrace code. But it left s390 behind.
> 
> Signed-off-by: Wander Lairson Costa <wander@redhat.com>
> ---
>  arch/s390/kernel/ftrace.c | 2 --
>  1 file changed, 2 deletions(-)

Thanks, but I applied already this one:
https://lore.kernel.org/r/20211208151503.1510381-1-jmarchan@redhat.com