Messages in this thread | | | Date | Mon, 29 Nov 2021 07:54:24 +0100 | From | Greg Kroah-Hartman <> | Subject | Re: [PATCH 2/3] topology/sysfs: export cluster attributes only if an architectures has support |
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On Sun, Nov 28, 2021 at 10:22:20PM +0100, Heiko Carstens wrote: > The cluster_id and cluster_cpus topology sysfs attributes have been > added with c5e22feffdd7 ("topology: Represent clusters of CPUs within > a die"). > > They are currently only used for x86, arm64, and riscv (via generic > arch topology), however they are still present with bogus default > values for all other architectures. Instead of enforcing such new > sysfs attributes to all architectures, make them only optional visible > if an architecture opts in by defining both the topology_cluster_id > and topology_cluster_cpumask attributes. > > This is similar to what was done when the book and drawer topology > levels were introduced: avoid useless and therefore confusing sysfs > attributes for architectures which cannot make use of them. > > This should not break any existing applications, since this is a > new interface introduced with the v5.16 merge window. > > Signed-off-by: Heiko Carstens <hca@linux.ibm.com> > --- > Documentation/admin-guide/cputopology.rst | 4 ++-- > drivers/base/topology.c | 8 ++++++++ > include/linux/topology.h | 2 ++ > 3 files changed, 12 insertions(+), 2 deletions(-) > > diff --git a/Documentation/admin-guide/cputopology.rst b/Documentation/admin-guide/cputopology.rst > index c68d07533c45..ad2238b41439 100644 > --- a/Documentation/admin-guide/cputopology.rst > +++ b/Documentation/admin-guide/cputopology.rst > @@ -11,8 +11,8 @@ Architecture-neutral, drivers/base/topology.c, exports these attributes. > However, the book and drawer related sysfs files will only be created if > CONFIG_SCHED_BOOK and CONFIG_SCHED_DRAWER are selected, respectively. > > -The die hierarchy related sysfs files will only be created if an architecture > -provides the related macros as described below. > +The die and cluster hierarchy related sysfs files will only be created if an > +architecture provides the related macros as described below. > > CONFIG_SCHED_BOOK and CONFIG_SCHED_DRAWER are currently only used on s390, > where they reflect the cpu and cache hierarchy. > diff --git a/drivers/base/topology.c b/drivers/base/topology.c > index 7fa5a7fbef25..1a288eac2c44 100644 > --- a/drivers/base/topology.c > +++ b/drivers/base/topology.c > @@ -50,8 +50,10 @@ define_id_show_func(die_id); > static DEVICE_ATTR_RO(die_id); > #endif > > +#ifndef topology_cluster_no_sysfs
Same comment here, do not enable an option that disables something :)
thanks,
greg k-h
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