[PATCH v2 1/2] arch: Introduce ARCH_HAS_CPUMASK_BITS

Yair Podemsky
2023-06-20T14:52:26Z

Some architectures set and maintain the mm_cpumask bits when loading
or removing process from cpu.
This Kconfig will mark those to allow different behavior between
kernels that maintain the mm_cpumask and those that do not.

Signed-off-by: Yair Podemsky <ypodemsk@redhat.com>
---
arch/Kconfig | 8 ++++++++
arch/arm/Kconfig | 1 +
arch/powerpc/Kconfig | 1 +
arch/s390/Kconfig | 1 +
arch/sparc/Kconfig | 1 +
arch/x86/Kconfig | 1 +
6 files changed, 13 insertions(+)

diff --git a/arch/Kconfig b/arch/Kconfig
index 205fd23e0cad..953fbfa5a2ad 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -1466,6 +1466,14 @@ config ARCH_HAS_NONLEAF_PMD_YOUNG
address translations. Page table walkers that clear the accessed bit
may use this capability to reduce their search space.

+config ARCH_HAS_CPUMASK_BITS
+ bool
+ help
+ Architectures that select this option set bits on the mm_cpumask
+ to mark which cpus loaded the mm, The mask can then be used to
+ control mm specific actions such as tlb_flush.
+
+
source "kernel/gcov/Kconfig"

source "scripts/gcc-plugins/Kconfig"
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 0fb4b218f665..cd20e96bc1dc 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -70,6 +70,7 @@ config ARM
select GENERIC_SMP_IDLE_THREAD
select HARDIRQS_SW_RESEND
select HAS_IOPORT
+ select ARCH_HAS_CPUMASK_BITS
select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT
select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index bff5820b7cda..c9218722aa2f 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -156,6 +156,7 @@ config PPC
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
select ARCH_HAS_UACCESS_FLUSHCACHE
select ARCH_HAS_UBSAN_SANITIZE_ALL
+ select ARCH_HAS_CPUMASK_BITS
select ARCH_HAVE_NMI_SAFE_CMPXCHG
select ARCH_KEEP_MEMBLOCK
select ARCH_MIGHT_HAVE_PC_PARPORT
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 6dab9c1be508..60bf29bc3f87 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -84,6 +84,7 @@ config S390
select ARCH_HAS_SYSCALL_WRAPPER
select ARCH_HAS_UBSAN_SANITIZE_ALL
select ARCH_HAS_VDSO_DATA
+ select ARCH_HAS_CPUMASK_BITS
select ARCH_HAVE_NMI_SAFE_CMPXCHG
select ARCH_INLINE_READ_LOCK
select ARCH_INLINE_READ_LOCK_BH
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 8535e19062f6..e8bf4d769306 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -99,6 +99,7 @@ config SPARC64
select ARCH_HAS_PTE_SPECIAL
select PCI_DOMAINS if PCI
select ARCH_HAS_GIGANTIC_PAGE
+ select ARCH_HAS_CPUMASK_BITS
select HAVE_SOFTIRQ_ON_OWN_STACK
select HAVE_SETUP_PER_CPU_AREA
select NEED_PER_CPU_EMBED_FIRST_CHUNK
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 53bab123a8ee..b351421695f3 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -185,6 +185,7 @@ config X86
select HAVE_ARCH_THREAD_STRUCT_WHITELIST
select HAVE_ARCH_STACKLEAK
select HAVE_ARCH_TRACEHOOK
+ select ARCH_HAS_CPUMASK_BITS
select HAVE_ARCH_TRANSPARENT_HUGEPAGE
select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
select HAVE_ARCH_USERFAULTFD_WP if X86_64 && USERFAULTFD
--
2.39.3