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| author | Andrei Vagin <avagin@gmail.com> | 2019-11-12 02:26:51 +0100 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2020-01-14 12:20:48 +0100 |
| commit | c966533f8c6c45f93c52599f8460e7695f0b7eaa (patch) | |
| tree | 3c2e611e0ec306e6e0fe30003b7305e9c483928c | |
| parent | lib/vdso: Add unlikely() hint into vdso_read_begin() (diff) | |
| download | linux-c966533f8c6c45f93c52599f8460e7695f0b7eaa.tar.xz linux-c966533f8c6c45f93c52599f8460e7695f0b7eaa.zip | |
lib/vdso: Mark do_hres() and do_coarse() as __always_inline
Performance numbers for Intel(R) Core(TM) i5-6300U CPU @ 2.40GHz
(more clock_gettime() cycles - the better):
clock | before | after | diff
----------------------------------------------------------
monotonic | 153222105 | 166775025 | 8.8%
monotonic-coarse | 671557054 | 691513017 | 3.0%
monotonic-raw | 147116067 | 161057395 | 9.5%
boottime | 153446224 | 166962668 | 9.1%
The improvement for arm64 for monotonic and boottime is around 3.5%.
clock | before | after | diff
==================================================
monotonic 17326692 17951770 3.6%
monotonic-coarse 43624027 44215292 1.3%
monotonic-raw 17541809 17554932 0.1%
boottime 17334982 17954361 3.5%
[ tglx: Avoid the goto ]
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-3-dima@arista.com
| -rw-r--r-- | lib/vdso/gettimeofday.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/lib/vdso/gettimeofday.c b/lib/vdso/gettimeofday.c index fac9e86ef124..b453d2469b63 100644 --- a/lib/vdso/gettimeofday.c +++ b/lib/vdso/gettimeofday.c @@ -38,7 +38,7 @@ u64 vdso_calc_delta(u64 cycles, u64 last, u64 mask, u32 mult) } #endif -static int do_hres(const struct vdso_data *vd, clockid_t clk, +static __always_inline int do_hres(const struct vdso_data *vd, clockid_t clk, struct __kernel_timespec *ts) { const struct vdso_timestamp *vdso_ts = &vd->basetime[clk]; @@ -68,8 +68,8 @@ static int do_hres(const struct vdso_data *vd, clockid_t clk, return 0; } -static int do_coarse(const struct vdso_data *vd, clockid_t clk, - struct __kernel_timespec *ts) +static __always_inline int do_coarse(const struct vdso_data *vd, clockid_t clk, + struct __kernel_timespec *ts) { const struct vdso_timestamp *vdso_ts = &vd->basetime[clk]; u32 seq; @@ -99,13 +99,15 @@ __cvdso_clock_gettime_common(clockid_t clock, struct __kernel_timespec *ts) */ msk = 1U << clock; if (likely(msk & VDSO_HRES)) - return do_hres(&vd[CS_HRES_COARSE], clock, ts); + vd = &vd[CS_HRES_COARSE]; else if (msk & VDSO_COARSE) return do_coarse(&vd[CS_HRES_COARSE], clock, ts); else if (msk & VDSO_RAW) - return do_hres(&vd[CS_RAW], clock, ts); + vd = &vd[CS_RAW]; + else + return -1; - return -1; + return do_hres(vd, clock, ts); } static __maybe_unused int |