Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml

[linux-drm-fsl-dcu.git] / arch / Kconfig

diff --git a/arch/Kconfig b/arch/Kconfig
index af2cc6eabcc781c4e8f7ee2067de75844ed5874d..f1cf895c040fb674ed1c07e5cc43459e9244a8f6 100644 (file)
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -207,9 +207,6 @@ config HAVE_DMA_ATTRS
 config HAVE_DMA_CONTIGUOUS
        bool
 
-config USE_GENERIC_SMP_HELPERS
-       bool
-
 config GENERIC_SMP_IDLE_THREAD
        bool
 
@@ -353,6 +350,18 @@ config HAVE_CONTEXT_TRACKING
 config HAVE_VIRT_CPU_ACCOUNTING
        bool
 
+config HAVE_VIRT_CPU_ACCOUNTING_GEN
+       bool
+       default y if 64BIT
+       help
+         With VIRT_CPU_ACCOUNTING_GEN, cputime_t becomes 64-bit.
+         Before enabling this option, arch code must be audited
+         to ensure there are no races in concurrent read/write of
+         cputime_t. For example, reading/writing 64-bit cputime_t on
+         some 32-bit arches may require multiple accesses, so proper
+         locking is needed to protect against concurrent accesses.
+
+
 config HAVE_IRQ_TIME_ACCOUNTING
        bool
        help
@@ -390,6 +399,16 @@ config HAVE_UNDERSCORE_SYMBOL_PREFIX
          Some architectures generate an _ in front of C symbols; things like
          module loading and assembly files need to know about this.
 
+config HAVE_IRQ_EXIT_ON_IRQ_STACK
+       bool
+       help
+         Architecture doesn't only execute the irq handler on the irq stack
+         but also irq_exit(). This way we can process softirqs on this irq
+         stack instead of switching to a new one when we call __do_softirq()
+         in the end of an hardirq.
+         This spares a stack switch and improves cache usage on softirq
+         processing.
+
 #
 # ABI hall of shame
 #