On Thu, 21 Aug 2025 14:28:24 +0200
Peter Zijlstra <pet...@infradead.org> wrote:
> Make is_optimized() return a tri-state and avoid return through
> argument. This simplifies things a little.
>
> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org>
> ---
> arch/x86/kernel/uprobes.c | 34 +++++++++++++---------------------
> 1 file changed, 13 insertions(+), 21 deletions(-)
>
> --- a/arch/x86/kernel/uprobes.c
> +++ b/arch/x86/kernel/uprobes.c
> @@ -1047,7 +1047,7 @@ static bool __is_optimized(uprobe_opcode
> return __in_uprobe_trampoline(vaddr + 5 + call->raddr);
> }
>
> -static int is_optimized(struct mm_struct *mm, unsigned long vaddr, bool
> *optimized)
> +static int is_optimized(struct mm_struct *mm, unsigned long vaddr)
> {
> uprobe_opcode_t insn[5];
> int err;
> @@ -1055,8 +1055,7 @@ static int is_optimized(struct mm_struct
> err = copy_from_vaddr(mm, vaddr, &insn, 5);
> if (err)
> return err;
> - *optimized = __is_optimized((uprobe_opcode_t *)&insn, vaddr);
> - return 0;
> + return __is_optimized((uprobe_opcode_t *)&insn, vaddr);
> }
>
> static bool should_optimize(struct arch_uprobe *auprobe)
> @@ -1069,17 +1068,14 @@ int set_swbp(struct arch_uprobe *auprobe
> unsigned long vaddr)
> {
> if (should_optimize(auprobe)) {
> - bool optimized = false;
> - int err;
> -
> /*
> * We could race with another thread that already optimized the
> probe,
> * so let's not overwrite it with int3 again in this case.
> */
> - err = is_optimized(vma->vm_mm, vaddr, &optimized);
> - if (err)
> - return err;
> - if (optimized)
> + int ret = is_optimized(vma->vm_mm, vaddr);
> + if (ret < 0)
> + return ret;
> + if (ret)
> return 0;
Looks like you should swap over 0 and 1.
That would then be: if (ret <= 0) return ret;
David
> }
> return uprobe_write_opcode(auprobe, vma, vaddr, UPROBE_SWBP_INSN,
> @@ -1090,17 +1086,13 @@ int set_orig_insn(struct arch_uprobe *au
> unsigned long vaddr)
> {
> if (test_bit(ARCH_UPROBE_FLAG_CAN_OPTIMIZE, &auprobe->flags)) {
> - struct mm_struct *mm = vma->vm_mm;
> - bool optimized = false;
> - int err;
> -
> - err = is_optimized(mm, vaddr, &optimized);
> - if (err)
> - return err;
> - if (optimized) {
> - err = swbp_unoptimize(auprobe, vma, vaddr);
> - WARN_ON_ONCE(err);
> - return err;
> + int ret = is_optimized(vma->vm_mm, vaddr);
> + if (ret < 0)
> + return ret;
> + if (ret) {
> + ret = swbp_unoptimize(auprobe, vma, vaddr);
> + WARN_ON_ONCE(ret);
> + return ret;
> }
> }
> return uprobe_write_opcode(auprobe, vma, vaddr, *(uprobe_opcode_t
> *)&auprobe->insn,
>
>
>
