Re: [PATCH v4 02/14] perf evsel: Refactor evsel__set_config_if_unset() arguments

[James Clark]

On 14/01/2026 3:47 pm, Arnaldo Carvalho de Melo wrote:
> On Wed, Jan 14, 2026 at 12:14:43PM +0000, James Clark wrote:
> > On 13/01/2026 10:13 pm, Arnaldo Carvalho de Melo wrote:
> > > On Mon, Dec 22, 2025 at 03:14:27PM +0000, James Clark wrote:
> > > > Make the evsel argument first to match the other evsel__* functions
> > > > and remove the redundant pmu argument, which can be accessed via evsel.
>
> > > I haven't checked if this is the exactly where this takes place but
> > > should be in this series, 32-bit build is broken:
>
> > >      3: almalinux:9-i386WARNING: image platform (linux/386) does not match the expected platform (linux/amd64)
> > > WARNING: image platform (linux/386) does not match the expected platform (linux/amd64)
> > >       21.72 almalinux:9-i386              : FAIL gcc version 11.4.1 20231218 (Red Hat 11.4.1-3) (GCC)
> > >        1378 |         perf_pmu__format_pack(&bits, val, vp, /*zero=*/true);
> > >             |                               ^~~~~
> > >             |                               |
> > >             |                               u64 * {aka long long unsigned int *}
> > >       In file included from util/evsel.h:14,
> > >                        from util/evsel.c:38:
> > >       util/pmu.h:282:43: note: expected ‘long unsigned int *’ but argument is of type ‘u64 *’ {aka ‘long long unsigned int *’}
> > >         282 | void perf_pmu__format_pack(unsigned long *format, __u64 value, __u64 *v,
> > >             |                            ~~~~~~~~~~~~~~~^~~~~~
>   
> > > What I have is in perf-tools-next/tmp.perf-tools-next BTW, I'll try and
> > > fix this tomorrow if you don't do it first. :-)
>   
> > Taking a look, but I'm wondering if this is already not working properly.
> > There are existing "unsigned long"s in pmu.c that operate on the config bits
> > which is what I copied.
>   
> > On this target an unsigned long is 32bits but struct
> > perf_event_attr->configs are __u64. So it looks like it might leave the top
> > bits unset sometimes.
>   
> > I'll look at a fix for that which should fix the compilation error at the
> > same time.
>   
> > Another question is, do we actually care about this platform?
>
> It failed for other 32-bit platforms too, so the question is if we care
> about 32-bit at all.
>
> - Arnaldo

I suppose the answer is we still do then.

I sent another version. A couple of patches were changed a bit where I 
used more bitfields instead of converting to u64s which was probably the 
right thing to do regardless of the build issue.