* Re: [PATCH] uprobe: Move arch_uprobe_optimize right after handlers execution
2025-10-01 13:24 [PATCH] uprobe: Move arch_uprobe_optimize right after handlers execution Jiri Olsa
@ 2025-10-01 16:39 ` Andrii Nakryiko
2025-10-01 23:20 ` Masami Hiramatsu
2025-10-03 11:48 ` Oleg Nesterov
2 siblings, 0 replies; 4+ messages in thread
From: Andrii Nakryiko @ 2025-10-01 16:39 UTC (permalink / raw)
To: Jiri Olsa
Cc: Oleg Nesterov, Peter Zijlstra, Andrii Nakryiko, Linus Torvalds,
bpf, linux-kernel, linux-trace-kernel, x86, Song Liu,
Yonghong Song, John Fastabend, Hao Luo, Steven Rostedt,
Masami Hiramatsu, Alan Maguire, David Laight,
Thomas Weißschuh, Ingo Molnar, Jann Horn, Alejandro Colomar
On Wed, Oct 1, 2025 at 6:25 AM Jiri Olsa <jolsa@kernel.org> wrote:
>
> It's less confusing to optimize uprobe right after handlers execution
> and before we do the check for changed ip register to avoid situations
> where changed ip register would skip uprobe optimization.
>
> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> ---
> kernel/events/uprobes.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
makes sense
Acked-by: Andrii Nakryiko <andrii@kernel.org>
> diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
> index 5dcf927310fd..c14ec27b976d 100644
> --- a/kernel/events/uprobes.c
> +++ b/kernel/events/uprobes.c
> @@ -2765,6 +2765,9 @@ static void handle_swbp(struct pt_regs *regs)
>
> handler_chain(uprobe, regs);
>
> + /* Try to optimize after first hit. */
> + arch_uprobe_optimize(&uprobe->arch, bp_vaddr);
> +
> /*
> * If user decided to take execution elsewhere, it makes little sense
> * to execute the original instruction, so let's skip it.
> @@ -2772,9 +2775,6 @@ static void handle_swbp(struct pt_regs *regs)
> if (instruction_pointer(regs) != bp_vaddr)
> goto out;
>
> - /* Try to optimize after first hit. */
> - arch_uprobe_optimize(&uprobe->arch, bp_vaddr);
> -
> if (arch_uprobe_skip_sstep(&uprobe->arch, regs))
> goto out;
>
> --
> 2.51.0
>
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] uprobe: Move arch_uprobe_optimize right after handlers execution
2025-10-01 13:24 [PATCH] uprobe: Move arch_uprobe_optimize right after handlers execution Jiri Olsa
2025-10-01 16:39 ` Andrii Nakryiko
@ 2025-10-01 23:20 ` Masami Hiramatsu
2025-10-03 11:48 ` Oleg Nesterov
2 siblings, 0 replies; 4+ messages in thread
From: Masami Hiramatsu @ 2025-10-01 23:20 UTC (permalink / raw)
To: Jiri Olsa
Cc: Oleg Nesterov, Peter Zijlstra, Andrii Nakryiko, Linus Torvalds,
bpf, linux-kernel, linux-trace-kernel, x86, Song Liu,
Yonghong Song, John Fastabend, Hao Luo, Steven Rostedt,
Masami Hiramatsu, Alan Maguire, David Laight,
Thomas Weißschuh, Ingo Molnar, Jann Horn, Alejandro Colomar
On Wed, 1 Oct 2025 15:24:49 +0200
Jiri Olsa <jolsa@kernel.org> wrote:
> It's less confusing to optimize uprobe right after handlers execution
> and before we do the check for changed ip register to avoid situations
> where changed ip register would skip uprobe optimization.
>
> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Looks good to me.
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Thanks,
> ---
> kernel/events/uprobes.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
> index 5dcf927310fd..c14ec27b976d 100644
> --- a/kernel/events/uprobes.c
> +++ b/kernel/events/uprobes.c
> @@ -2765,6 +2765,9 @@ static void handle_swbp(struct pt_regs *regs)
>
> handler_chain(uprobe, regs);
>
> + /* Try to optimize after first hit. */
> + arch_uprobe_optimize(&uprobe->arch, bp_vaddr);
> +
> /*
> * If user decided to take execution elsewhere, it makes little sense
> * to execute the original instruction, so let's skip it.
> @@ -2772,9 +2775,6 @@ static void handle_swbp(struct pt_regs *regs)
> if (instruction_pointer(regs) != bp_vaddr)
> goto out;
>
> - /* Try to optimize after first hit. */
> - arch_uprobe_optimize(&uprobe->arch, bp_vaddr);
> -
> if (arch_uprobe_skip_sstep(&uprobe->arch, regs))
> goto out;
>
> --
> 2.51.0
>
--
Masami Hiramatsu (Google) <mhiramat@kernel.org>
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] uprobe: Move arch_uprobe_optimize right after handlers execution
2025-10-01 13:24 [PATCH] uprobe: Move arch_uprobe_optimize right after handlers execution Jiri Olsa
2025-10-01 16:39 ` Andrii Nakryiko
2025-10-01 23:20 ` Masami Hiramatsu
@ 2025-10-03 11:48 ` Oleg Nesterov
2 siblings, 0 replies; 4+ messages in thread
From: Oleg Nesterov @ 2025-10-03 11:48 UTC (permalink / raw)
To: Jiri Olsa
Cc: Peter Zijlstra, Andrii Nakryiko, Linus Torvalds, bpf,
linux-kernel, linux-trace-kernel, x86, Song Liu, Yonghong Song,
John Fastabend, Hao Luo, Steven Rostedt, Masami Hiramatsu,
Alan Maguire, David Laight, Thomas Weißschuh, Ingo Molnar,
Jann Horn, Alejandro Colomar
On 10/01, Jiri Olsa wrote:
>
> --- a/kernel/events/uprobes.c
> +++ b/kernel/events/uprobes.c
> @@ -2765,6 +2765,9 @@ static void handle_swbp(struct pt_regs *regs)
>
> handler_chain(uprobe, regs);
>
> + /* Try to optimize after first hit. */
> + arch_uprobe_optimize(&uprobe->arch, bp_vaddr);
> +
> /*
> * If user decided to take execution elsewhere, it makes little sense
> * to execute the original instruction, so let's skip it.
> @@ -2772,9 +2775,6 @@ static void handle_swbp(struct pt_regs *regs)
> if (instruction_pointer(regs) != bp_vaddr)
> goto out;
>
> - /* Try to optimize after first hit. */
> - arch_uprobe_optimize(&uprobe->arch, bp_vaddr);
> -
> if (arch_uprobe_skip_sstep(&uprobe->arch, regs))
> goto out;
Acked-by: Oleg Nesterov <oleg@redhat.com>
^ permalink raw reply [flat|nested] 4+ messages in thread