[PATCH v1 00/11] perf script: Refactor branch flags for Arm SPE

Namhyung Kim namhyung at kernel.org
Wed Feb 12 21:29:28 PST 2025


On Wed, Feb 12, 2025 at 08:14:48AM -0800, Ian Rogers wrote:
> On Wed, Feb 12, 2025 at 12:54 AM Leo Yan <leo.yan at arm.com> wrote:
> >
> > Hi Ian,
> >
> > On Tue, Feb 11, 2025 at 02:34:46PM -0800, Ian Rogers wrote:
> > > On Wed, Feb 5, 2025 at 4:16 AM Leo Yan <leo.yan at arm.com> wrote:
> > > >
> > > > This patch series refactors branch flags for support Arm SPE.  The patch
> > > > set is divided into two parts, the first part is for refactoring common
> > > > code and the second part is for enabling Arm SPE.
> >
> > [...]
> > >
> > > Reviewed-by: Ian Rogers <irogers at google.com>
> > >
> > > Built and tested (on x86). A little strange patch 5 adds a new bit not
> > > at the end, but "Sample parsing" test wasn't broken so looks like it
> > > is good. I was surprised the use of value in the union:
> > > ```
> > > struct branch_flags {
> > > union {
> > > u64 value;
> > > struct {
> > > u64 mispred:1;
> > > u64 predicted:1;
> > > ...
> > > ```
> > > didn't get broken. Perhaps there's an opportunity for additional tests.

Probably because it just checks the value as a whole u64, not each
bitfield.  But it seems to test if the value of the input sample data
and synthesized-and-parsed output sample data is same.  So it may not be
important what value it has.

Anyway it'd be nice if any ARM folks can review this series.

Thanks,
Namhyung




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