Re: tprof(8) ABI

[Nick Hudson <nick.hudson%gmx.co.uk@localhost>]

On 15/04/2026 05:09, Kevin Bowling wrote:
> I implemented a tprof driver for mips octeon, but the port typically
> runs an n32 userland.  This can be worked around by compiling an LP64
> tprof(8), but I am not sure how that would work with the package sets.
> Since it is a developer tool, I propose intentionally breaking the ABI
> like the following patch.  I think it would improve other 32 on 64
> situations at the cost of an ABI break, but it is a developer tool in
> /usr/sbin so maybe this is the most pragmatic solution?
> --- a/sys/dev/tprof/tprof_types.h
> +++ b/sys/dev/tprof/tprof_types.h
> @@ -50,7 +50,8 @@ typedef struct {
>         uint32_t s_flags;       /* flags and counterID */
>  #define TPROF_SAMPLE_INKERNEL  0x00000001 /* s_pc is in kernel address space */
>  #define        TPROF_SAMPLE_COUNTER_MASK 0xff000000 /*
> 0..(TPROF_MAXCOUNTERS-1) */
> -       uintptr_t s_pc;         /* program counter */
> +       uint64_t s_pc;          /* program counter; uint64_t for ABI compat
> +                                * with 64-bit kernels and n32/ILP32 userland */
>  } tprof_sample_t;
>  typedef struct tprof_param {

I have mostly completely forgotten MIPS ABIs, but shouldn't the PC just be sign extended?