Re: [PATCH -tip -v10 5/7] x86: add pt_regs register and stack access APIs

[Andi Kleen <andi@firstfloor.org>]

Masami Hiramatsu <mhiramat@redhat.com> writes:

> Add following APIs for accessing registers and stack entries from pt_regs.

You forgot to state who calls these functions/why are they added?
Who only has strings for registers?

I can see the point of having a function for nth argument though,
that's useful.

> +static inline unsigned long regs_get_argument_nth(struct pt_regs *regs,
> +						  unsigned n)
> +{
> +	if (n < NR_REGPARMS) {
> +		switch (n) {
> +		case 0:
> +			return regs->ax;
> +		case 1:
> +			return regs->dx;
> +		case 2:
> +			return regs->cx;


[....]

That could be done shorter with a offsetof table.

> +	if (n < NR_REGPARMS) {
> +		switch (n) {
> +		case 0:
> +			return regs->di;
> +		case 1:
> +			return regs->si;
> +		case 2:
> +			return regs->dx;
> +		case 3:
> +			return regs->cx;
> +		case 4:
> +			return regs->r8;
> +		case 5:
> +			return regs->r9;

and that too.


-Andi
-- 
ak@linux.intel.com -- Speaking for myself only.