[PATCH v1 1/4] lib/vdso: Mark do_hres_timens() and do_coarse_timens() __always_inline()

From: Christophe Leroy
Date: Wed Mar 31 2021 - 10:50:47 EST


In the same spirit as commit c966533f8c6c ("lib/vdso: Mark do_hres()
and do_coarse() as __always_inline"), mark do_hres_timens() and
do_coarse_timens() __always_inline.

The measurement below in on a non timens process, ie on the fastest path.

On powerpc32, without the patch:

clock-gettime-monotonic-raw: vdso: 1155 nsec/call
clock-gettime-monotonic-coarse: vdso: 813 nsec/call
clock-gettime-monotonic: vdso: 1076 nsec/call

With the patch:

clock-gettime-monotonic-raw: vdso: 1100 nsec/call
clock-gettime-monotonic-coarse: vdso: 667 nsec/call
clock-gettime-monotonic: vdso: 1025 nsec/call

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
---
lib/vdso/gettimeofday.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/lib/vdso/gettimeofday.c b/lib/vdso/gettimeofday.c
index 2919f1698140..c6f6dee08746 100644
--- a/lib/vdso/gettimeofday.c
+++ b/lib/vdso/gettimeofday.c
@@ -46,8 +46,8 @@ static inline bool vdso_cycles_ok(u64 cycles)
#endif

#ifdef CONFIG_TIME_NS
-static int do_hres_timens(const struct vdso_data *vdns, clockid_t clk,
- struct __kernel_timespec *ts)
+static __always_inline int do_hres_timens(const struct vdso_data *vdns, clockid_t clk,
+ struct __kernel_timespec *ts)
{
const struct vdso_data *vd = __arch_get_timens_vdso_data();
const struct timens_offset *offs = &vdns->offset[clk];
@@ -97,8 +97,8 @@ static __always_inline const struct vdso_data *__arch_get_timens_vdso_data(void)
return NULL;
}

-static int do_hres_timens(const struct vdso_data *vdns, clockid_t clk,
- struct __kernel_timespec *ts)
+static __always_inline int do_hres_timens(const struct vdso_data *vdns, clockid_t clk,
+ struct __kernel_timespec *ts)
{
return -EINVAL;
}
@@ -159,8 +159,8 @@ static __always_inline int do_hres(const struct vdso_data *vd, clockid_t clk,
}

#ifdef CONFIG_TIME_NS
-static int do_coarse_timens(const struct vdso_data *vdns, clockid_t clk,
- struct __kernel_timespec *ts)
+static __always_inline int do_coarse_timens(const struct vdso_data *vdns, clockid_t clk,
+ struct __kernel_timespec *ts)
{
const struct vdso_data *vd = __arch_get_timens_vdso_data();
const struct vdso_timestamp *vdso_ts = &vd->basetime[clk];
@@ -188,8 +188,8 @@ static int do_coarse_timens(const struct vdso_data *vdns, clockid_t clk,
return 0;
}
#else
-static int do_coarse_timens(const struct vdso_data *vdns, clockid_t clk,
- struct __kernel_timespec *ts)
+static __always_inline int do_coarse_timens(const struct vdso_data *vdns, clockid_t clk,
+ struct __kernel_timespec *ts)
{
return -1;
}
--
2.25.0