[tip:core/types] jiffies: Force inlining of {m,u}msecs_to_jiffies ()

From: tip-bot for Denys Vlasenko
Date: Wed Aug 05 2015 - 16:14:48 EST


Commit-ID: accd0b9ec015d611eb7783dd86f1bb31bf8d62ab
Gitweb: http://git.kernel.org/tip/accd0b9ec015d611eb7783dd86f1bb31bf8d62ab
Author: Denys Vlasenko <dvlasenk@xxxxxxxxxx>
AuthorDate: Tue, 4 Aug 2015 16:15:16 +0200
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Wed, 5 Aug 2015 09:38:09 +0200

jiffies: Force inlining of {m,u}msecs_to_jiffies()

With this config:

http://busybox.net/~vda/kernel_config_OPTIMIZE_INLINING_and_Os

gcc-4.7.2 generates many copies of these tiny functions:

msecs_to_jiffies (45 copies):
55 push %rbp
48 89 e5 mov %rsp,%rbp
e8 59 ec 03 00 callq __msecs_to_jiffies
5d pop %rbp
c3 retq

usecs_to_jiffies (10 copies):
55 push %rbp
48 89 e5 mov %rsp,%rbp
e8 5d 54 5e ff callq __usecs_to_jiffies
5d pop %rbp
c3 retq

See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66122

This patch fixes this via s/inline/__always_inline/

text data bss dec filename
86970954 17195912 36659200 140826066 vmlinux.before
86966150 17195912 36659200 140821262 vmlinux

Signed-off-by: Denys Vlasenko <dvlasenk@xxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Thomas Graf <tgraf@xxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/1438697716-28121-3-git-send-email-dvlasenk@xxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
include/linux/jiffies.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/jiffies.h b/include/linux/jiffies.h
index 535fd3b..1ba48a1 100644
--- a/include/linux/jiffies.h
+++ b/include/linux/jiffies.h
@@ -351,7 +351,7 @@ static inline unsigned long _msecs_to_jiffies(const unsigned int m)
* directly here and from __msecs_to_jiffies() in the case where
* constant folding is not possible.
*/
-static inline unsigned long msecs_to_jiffies(const unsigned int m)
+static __always_inline unsigned long msecs_to_jiffies(const unsigned int m)
{
if (__builtin_constant_p(m)) {
if ((int)m < 0)
@@ -405,7 +405,7 @@ static inline unsigned long _usecs_to_jiffies(const unsigned int u)
* directly here and from __msecs_to_jiffies() in the case where
* constant folding is not possible.
*/
-static inline unsigned long usecs_to_jiffies(const unsigned int u)
+static __always_inline unsigned long usecs_to_jiffies(const unsigned int u)
{
if (__builtin_constant_p(u)) {
if (u > jiffies_to_usecs(MAX_JIFFY_OFFSET))
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/