diff options
| author | Kiryl Shutsemau (Meta) <kas@kernel.org> | 2026-07-08 12:14:02 +0100 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2026-08-04 19:18:36 -0700 |
| commit | c6f11553c067d7d9ed2dcffe1e01780441d4e6e2 (patch) | |
| tree | 2a4b40169ce1cc719a4d9979820ca32a767a6af7 /init/Kconfig | |
| parent | 889d3783ae3f78c8593bc7837a2a68b49db4166d (diff) | |
mm: decouple protnone helpers from CONFIG_NUMA_BALANCING
Patch series "userfaultfd: working set tracking for VM guest memory", v10.
This series adds userfaultfd support for tracking the working set of VM
guest memory, so a VMM can identify hot pages and reclaim cold ones to
tiered or remote storage.
This patch (of 15):
pte_protnone() and pmd_protnone() detect present-but-inaccessible page
table entries. This capability is useful beyond NUMA balancing -- for
example, userfaultfd working set tracking uses protnone PTEs to track page
access without unmapping pages.
Introduce CONFIG_ARCH_HAS_PTE_PROTNONE to decouple the protnone PTE
infrastructure from CONFIG_NUMA_BALANCING. The six architectures that
support protnone PTEs (x86_64, arm64, powerpc, s390, riscv, loongarch) now
select this option, and CONFIG_NUMA_BALANCING depends on it.
No functional change -- the same set of architectures continues to have
working protnone support, but the infrastructure is now available
independently of NUMA balancing.
Link: https://lore.kernel.org/20260708111417.173443-1-kirill@shutemov.name
Link: https://lore.kernel.org/20260708111417.173443-2-kirill@shutemov.name
Signed-off-by: Kiryl Shutsemau (Meta) <kas@kernel.org>
Assisted-by: Claude:claude-opus-4-6
Acked-by: SeongJae Park <sj@kernel.org>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: James Houghton <jthoughton@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'init/Kconfig')
| -rw-r--r-- | init/Kconfig | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/init/Kconfig b/init/Kconfig index 10f2013b5321..c24f345f794b 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -948,6 +948,13 @@ config SCHED_PROXY_EXEC endmenu # +# For architectures that support present-but-inaccessible (PROT_NONE) page +# table entries detectable via pte_protnone() / pmd_protnone(): +# +config ARCH_HAS_PTE_PROTNONE + bool + +# # For architectures that want to enable the support for NUMA-affine scheduler # balancing logic: # @@ -1013,6 +1020,7 @@ config ARCH_WANT_NUMA_VARIABLE_LOCALITY config NUMA_BALANCING bool "Memory placement aware NUMA scheduler" depends on ARCH_SUPPORTS_NUMA_BALANCING + depends on ARCH_HAS_PTE_PROTNONE depends on !ARCH_WANT_NUMA_VARIABLE_LOCALITY depends on SMP && NUMA_MIGRATION && !PREEMPT_RT help |