Commit-ID:  accd0b9ec015d611eb7783dd86f1bb31bf8d62ab
Gitweb:     http://git.kernel.org/tip/accd0b9ec015d611eb7783dd86f1bb31bf8d62ab
Author:     Denys Vlasenko <dvlas...@redhat.com>
AuthorDate: Tue, 4 Aug 2015 16:15:16 +0200
Committer:  Ingo Molnar <mi...@kernel.org>
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 <dvlas...@redhat.com>
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: David Rientjes <rient...@google.com>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Thomas Graf <tg...@suug.ch>
Cc: linux-kernel@vger.kernel.org
Link: 
http://lkml.kernel.org/r/1438697716-28121-3-git-send-email-dvlas...@redhat.com
Signed-off-by: Ingo Molnar <mi...@kernel.org>
---
 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))
--
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