clock_getres in the vDSO library has to preserve the same behaviour of posix_get_hrtimer_res().
In particular, posix_get_hrtimer_res() does: sec = 0; ns = hrtimer_resolution; and hrtimer_resolution depends on the enablement of the high resolution timers that can happen either at compile or at run time.
Fix the nds32 vdso implementation of clock_getres keeping a copy of hrtimer_resolution in vdso data and using that directly.
Cc: Greentime Hu green.hu@gmail.com Cc: Vincent Chen deanbo422@gmail.com Signed-off-by: Vincenzo Frascino vincenzo.frascino@arm.com --- arch/nds32/include/asm/vdso_datapage.h | 1 + arch/nds32/kernel/vdso.c | 1 + arch/nds32/kernel/vdso/gettimeofday.c | 4 +++- 3 files changed, 5 insertions(+), 1 deletion(-)
diff --git a/arch/nds32/include/asm/vdso_datapage.h b/arch/nds32/include/asm/vdso_datapage.h index 79db5a12ca5e..34d80548297f 100644 --- a/arch/nds32/include/asm/vdso_datapage.h +++ b/arch/nds32/include/asm/vdso_datapage.h @@ -20,6 +20,7 @@ struct vdso_data { u32 xtime_clock_sec; /* CLOCK_REALTIME - seconds */ u32 cs_mult; /* clocksource multiplier */ u32 cs_shift; /* Cycle to nanosecond divisor (power of two) */ + u32 hrtimer_res; /* hrtimer resolution */
u64 cs_cycle_last; /* last cycle value */ u64 cs_mask; /* clocksource mask */ diff --git a/arch/nds32/kernel/vdso.c b/arch/nds32/kernel/vdso.c index 016f15891f6d..90bcae6f8554 100644 --- a/arch/nds32/kernel/vdso.c +++ b/arch/nds32/kernel/vdso.c @@ -220,6 +220,7 @@ void update_vsyscall(struct timekeeper *tk) vdso_data->xtime_coarse_sec = tk->xtime_sec; vdso_data->xtime_coarse_nsec = tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift; + vdso_data->hrtimer_res = hrtimer_resolution; vdso_write_end(vdso_data); }
diff --git a/arch/nds32/kernel/vdso/gettimeofday.c b/arch/nds32/kernel/vdso/gettimeofday.c index 038721af40e3..b02581891c33 100644 --- a/arch/nds32/kernel/vdso/gettimeofday.c +++ b/arch/nds32/kernel/vdso/gettimeofday.c @@ -208,6 +208,8 @@ static notrace int clock_getres_fallback(clockid_t _clk_id,
notrace int __vdso_clock_getres(clockid_t clk_id, struct timespec *res) { + struct vdso_data *vdata = __get_datapage(); + if (res == NULL) return 0; switch (clk_id) { @@ -215,7 +217,7 @@ notrace int __vdso_clock_getres(clockid_t clk_id, struct timespec *res) case CLOCK_MONOTONIC: case CLOCK_MONOTONIC_RAW: res->tv_sec = 0; - res->tv_nsec = CLOCK_REALTIME_RES; + res->tv_nsec = vdata->hrtimer_res; break; case CLOCK_REALTIME_COARSE: case CLOCK_MONOTONIC_COARSE: