GitHub-Mirror/linux-bl808
2
0
Fork 0
mirror of https://github.com/Fishwaldo/linux-bl808.git synced 2025-06-17 20:25:19 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

x86: add optimized inlining

Browse source 
add CONFIG_OPTIMIZE_INLINING=y.

allow gcc to optimize the kernel image's size by uninlining
functions that have been marked 'inline'. Previously gcc was
forced by Linux to always-inline these functions via a gcc
attribute:

 #define inline	inline __attribute__((always_inline))

Especially when the user has already selected
CONFIG_OPTIMIZE_FOR_SIZE=y this can make a huge difference in
kernel image size (using a standard Fedora .config):

   text    data     bss     dec           hex filename
   5613924  562708 3854336 10030968    990f78 vmlinux.before
   5486689  562708 3854336  9903733    971e75 vmlinux.after

that's a 2.3% text size reduction (!).

Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Ingo Molnar 2008-03-03 12:38:52 +01:00
parent b1721d0da2
commit 60a3cdd063
4 changed files with 24 additions and 3 deletions
Download patch file Download diff file Expand all files Collapse all files

12
include/linux/compiler-gcc.h
View file

@ -28,9 +28,15 @@
#define __must_be_array(a) \
BUILD_BUG_ON_ZERO(__builtin_types_compatible_p(typeof(a), typeof(&a[0])))
#define inline inline __attribute__((always_inline))
#define __inline__ __inline__ __attribute__((always_inline))
#define __inline __inline __attribute__((always_inline))
/*
* Force always-inline if the user requests it so via the .config:
*/
#if !defined(CONFIG_OPTIMIZE_INLINING) && (__GNUC__ >= 4)
# define inline inline __attribute__((always_inline))
# define __inline__ __inline__ __attribute__((always_inline))
# define __inline __inline __attribute__((always_inline))
#endif
#define __deprecated __attribute__((deprecated))
#define __packed __attribute__((packed))
#define __weak __attribute__((weak))