[PATCH v6 1/6] perf arm64: Allow version comparisons of CPU IDs

[John Garry]

On 16/08/2023 12:47, James Clark wrote:
> Currently variant and revision fields are masked out of the MIDR so
> it's not possible to compare different versions of the same CPU.
> In a later commit a workaround will be removed just for N2 r0p3, so
> enable comparisons on version.
> 
> This has the side effect of changing the MIDR stored in the header of
> the perf.data file to no longer have masked version fields. It also
> affects the lookups in mapfile.csv, but as that currently only has
> zeroed version fields, it has no actual effect. The mapfile.csv
> documentation also states to zero the version fields, so unless this
> isn't done it will continue to have no effect.
> 
> There is an existing weak default strcmp_cpuid_str() function, and an
> x86 version. This adds another version for arm64.
> 
> Signed-off-by: James Clark<james.clark at arm.com>

Reviewed-by: John Garry <john.g.garry at oracle.com>