sched, x86: add HAVE_UNSTABLE_SCHED_CLOCK

add the HAVE_UNSTABLE_SCHED_CLOCK, for architectures to select.

the next change utilizes it.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 7 insertions, 0 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 845ea2b2d487..bbcafaa160c0 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -18,6 +18,7 @@ config X86_64
 ### Arch settings
 config X86
         def_bool y
+        select HAVE_UNSTABLE_SCHED_CLOCK
         select HAVE_IDE
         select HAVE_OPROFILE
         select HAVE_KPROBES
diff --git a/init/Kconfig b/init/Kconfig
index f0e62e5ce0dc..fa42e6b549d3 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -316,6 +316,12 @@ config CPUSETS
 
           Say N if unsure.
 
+#
+# Architectures with an unreliable sched_clock() should select this:
+#
+config HAVE_UNSTABLE_SCHED_CLOCK
+        bool
+
 config GROUP_SCHED
         bool "Group CPU scheduler"
         default y