[PATCH RT] Revert "cpumask: Disable CONFIG_CPUMASK_OFFSTACK for RT"

From: Sebastian Andrzej Siewior
Date: Wed Dec 18 2019 - 12:42:04 EST


The one x86 case we had was fixed in commit
832df3d47badc ("x86/smp: Enhance native_send_call_func_ipi()")

I didn't find another in-IRQ user. Most callers use GFP_KERNEL and the
ATOMIC users are allocating the mask while holding a spinlock_t.

Allow to use CPUMASK_OFFSTACK becauase it no longer is a problem on RT.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
---
arch/x86/Kconfig | 2 +-
lib/Kconfig | 1 -
2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 7f359aacf8148..4b77b3273051e 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -967,7 +967,7 @@ config CALGARY_IOMMU_ENABLED_BY_DEFAULT
config MAXSMP
bool "Enable Maximum number of SMP Processors and NUMA Nodes"
depends on X86_64 && SMP && DEBUG_KERNEL
- select CPUMASK_OFFSTACK if !PREEMPT_RT
+ select CPUMASK_OFFSTACK
---help---
Enable maximum number of CPUS and NUMA Nodes for this architecture.
If unsure, say N.
diff --git a/lib/Kconfig b/lib/Kconfig
index 298b41298e487..3321d04dfa5a5 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -468,7 +468,6 @@ config CHECK_SIGNATURE

config CPUMASK_OFFSTACK
bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
- depends on !PREEMPT_RT
help
Use dynamic allocation for cpumask_var_t, instead of putting
them on the stack. This is a bit more expensive, but avoids
--
2.24.0