[PATCH 2/2] x86-64: Inline vdso clock_gettime helpers

From: Andy Lutomirski
Date: Fri Mar 23 2012 - 00:16:02 EST


From: Andy Lutomirski <luto@xxxxxxx>

This is about a 3% speedup on Sandy Bridge.

Signed-off-by: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
---
arch/x86/vdso/vclock_gettime.c | 9 +++++----
1 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/x86/vdso/vclock_gettime.c b/arch/x86/vdso/vclock_gettime.c
index 6eea70b8..885eff4 100644
--- a/arch/x86/vdso/vclock_gettime.c
+++ b/arch/x86/vdso/vclock_gettime.c
@@ -94,7 +94,8 @@ notrace static inline long vgetns(void)
return (v * gtod->clock.mult) >> gtod->clock.shift;
}

-notrace static noinline int do_realtime(struct timespec *ts)
+/* Code size doesn't matter (vdso is 4k anyway) and this is faster. */
+notrace static int __always_inline do_realtime(struct timespec *ts)
{
unsigned long seq, ns;
int mode;
@@ -111,7 +112,7 @@ notrace static noinline int do_realtime(struct timespec *ts)
return mode;
}

-notrace static noinline int do_monotonic(struct timespec *ts)
+notrace static int do_monotonic(struct timespec *ts)
{
unsigned long seq, ns;
int mode;
@@ -128,7 +129,7 @@ notrace static noinline int do_monotonic(struct timespec *ts)
return mode;
}

-notrace static noinline int do_realtime_coarse(struct timespec *ts)
+notrace static int do_realtime_coarse(struct timespec *ts)
{
unsigned long seq;
do {
@@ -139,7 +140,7 @@ notrace static noinline int do_realtime_coarse(struct timespec *ts)
return 0;
}

-notrace static noinline int do_monotonic_coarse(struct timespec *ts)
+notrace static int do_monotonic_coarse(struct timespec *ts)
{
unsigned long seq;
do {
--
1.7.7.6

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