[PATCH 2/2] arm: add optimized inlining

[sboyd@codeaurora.org (Stephen Boyd)]

This patch is inspired by 60a3cdd (x86: add optimized inlining,
2008-03-03). GCC is currently being forced to inline whatever
functions are marked as inline (due to the #define of inline to
the gcc attribute always_inline). The 4.x series of GCC has a
rewritten inlining algorithm which should be good enough for the
kernel's purposes. Enabling this option will allow GCC to decide
when to inline a function marked as inline. Since it's opt-in and
doesn't affect functions marked as always_inline there shouldn't
be much harm in allowing people to enable this. If there is, we
should find the affected functions and mark them as always_inline.

	text    data     bss     dec     hex filename
	5987182  246104  926696 7159982  6d40ae vmlinux.orig
	5794190  246104  926744 6967038  6a4efe vmlinux.new

It reduces the text section of my kernel by 3.3%, which is pretty
nice.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
---
 arch/arm/Kconfig |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index db524e7..1ed7968 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -23,6 +23,7 @@ config ARM
 	select PERF_USE_VMALLOC
 	select HAVE_REGS_AND_STACK_ACCESS_API
 	select HAVE_HW_BREAKPOINT if (PERF_EVENTS && (CPU_V6 || CPU_V7))
+	select ARCH_SUPPORTS_OPTIMIZED_INLINING
 	help
 	  The ARM series is a line of low-power-consumption RISC chip designs
 	  licensed by ARM Ltd and targeted at embedded applications and
-- 
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The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.