Re: [PATCH v5] arm64: implement ftrace with regs

From: Torsten Duwe
Date: Fri Dec 14 2018 - 04:47:17 EST


On Thu, Dec 13, 2018 at 11:01:38PM +0530, Amit Daniel Kachhap wrote:
> On Fri, Nov 30, 2018 at 9:53 PM Torsten Duwe <duwe@xxxxxx> wrote:
>
> Hi Torsten,
>
> I was testing your patch and it seems to work fine for function trace. However
> function graph trace seems broken. Is it work in progress ? or I am
> missing something.

What did you base your tests on, you didn't specify?
OTOH neither did I ;-) I precluded all addressees had the full picture.

Precisely, I basically start with 4.19, but 4.20-rc shouldn't make a
difference. BUT...

> > [Changes from v4]
> >
> > * include Ard's feedback and pending changes:
> > - ADR/ADRP veneers
> > - ftrace_trampolines[2]
> > - add a .req for fp, just in case
" [PATCH 1/2] arm64/insn: add support for emitting ADR/ADRP instructions "
<20181122084646.3247-2-ard.biesheuvel@xxxxxxxxxx> et.al, esp:
Git-commit: bdb85cd1d20669dfae813555dddb745ad09323ba

> > - comment on the pt_regs.stackframe[2] mapping
> > * include Mark's ftrace cleanup
> > - GLOBAL()
> > - prepare_ftrace_return(pc, &lr, fp)
> >
" [PATCH 1/6] linkage: add generic GLOBAL() macro "
<20181115224203.24847-2-mark.rutland@xxxxxxx> et.al., esp:
Git-commit: 7dc48bf96aa0fc8aa5b38cc3e5c36ac03171e680

change the API this patch set relies on. AFAIU they are on their way into
mainline so I updated v5 accordingly. If you don't have these, just use v4;
the other changes are only for compatibility and cosmetics.

HTH,
Torsten