jump label: Add work around to i386 gcc asm goto bug

[pandora-kernel.git] / arch / Kconfig

diff --git a/arch/Kconfig b/arch/Kconfig
index 53d7f61..8bf0fa6 100644 (file)
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -42,6 +42,20 @@ config KPROBES
          for kernel debugging, non-intrusive instrumentation and testing.
          If in doubt, say "N".
 
+config JUMP_LABEL
+       bool "Optimize trace point call sites"
+       depends on HAVE_ARCH_JUMP_LABEL
+       help
+         If it is detected that the compiler has support for "asm goto",
+        the kernel will compile trace point locations with just a
+        nop instruction. When trace points are enabled, the nop will
+        be converted to a jump to the trace function. This technique
+        lowers overhead and stress on the branch prediction of the
+        processor.
+
+        On i386, options added to the compiler flags may increase
+        the size of the kernel slightly.
+
 config OPTPROBES
        def_bool y
        depends on KPROBES && HAVE_OPTPROBES