[PATCH] Make CONFIG_REGPARM enabled by default

Make CONFIG_REGPARM enabled by default.  It's a noticable win both for size
and for performance, and gcc[34] handles it correctly.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 10 insertions, 2 deletions

diff --git a/arch/i386/Kconfig b/arch/i386/Kconfig
index 69c8a70e854..5f89c74537e 100644
--- a/arch/i386/Kconfig
+++ b/arch/i386/Kconfig
@@ -661,9 +661,17 @@ config BOOT_IOREMAP
 
 config REGPARM
         bool "Use register arguments"
+        default y
         help
-        Compile the kernel with -mregparm=3. This uses a different ABI
-        and passes the first three arguments of a function call in registers.
+        Compile the kernel with -mregparm=3. This instructs gcc to use
+        a more efficient function call ABI which passes the first three
+        arguments of a function call via registers, which results in denser
+        and faster code.
+
+        If this option is disabled, then the default ABI of passing
+        arguments via the stack is used.
+
+        If unsure, say Y.
 
 config SECCOMP
         bool "Enable seccomp to safely compute untrusted bytecode"