On 04/28 15:09:56, Petri Savolainen wrote:
> Use 64 bit HW time counter when available. It is used on
> x86 when invariant TSC CPU flag indicates that TSC frequency
> is constant. Otherwise, the system time is used as before. Direct
> HW time counter usage avoids system call, and related latency
> and performance issues.
>
> Signed-off-by: Petri Savolainen <[email protected]>
> ---
> platform/linux-generic/Makefile.am | 1 +
> platform/linux-generic/arch/arm/odp_cpu_arch.c | 16 ++
> platform/linux-generic/arch/default/odp_cpu_arch.c | 16 ++
> platform/linux-generic/arch/mips64/odp_cpu_arch.c | 16 ++
> platform/linux-generic/arch/powerpc/odp_cpu_arch.c | 16 ++
> platform/linux-generic/arch/x86/cpu_flags.c | 9 +
> platform/linux-generic/arch/x86/odp_cpu_arch.c | 59 ++++
> .../include/odp/api/plat/time_types.h | 23 +-
> platform/linux-generic/include/odp_time_internal.h | 24 ++
> platform/linux-generic/odp_time.c | 300
> ++++++++++++++++-----
> 10 files changed, 415 insertions(+), 65 deletions(-)
> create mode 100644 platform/linux-generic/include/odp_time_internal.h
>
> diff --git a/platform/linux-generic/Makefile.am
> b/platform/linux-generic/Makefile.am
> index ab74c14c..cd7afba2 100644
> --- a/platform/linux-generic/Makefile.am
> +++ b/platform/linux-generic/Makefile.am
> @@ -172,6 +172,7 @@ noinst_HEADERS = \
> ${srcdir}/include/odp_schedule_if.h \
> ${srcdir}/include/odp_sorted_list_internal.h \
> ${srcdir}/include/odp_shm_internal.h \
> + ${srcdir}/include/odp_time_internal.h \
> ${srcdir}/include/odp_timer_internal.h \
> ${srcdir}/include/odp_timer_wheel_internal.h \
> ${srcdir}/include/odp_traffic_mngr_internal.h \
> diff --git a/platform/linux-generic/arch/arm/odp_cpu_arch.c
> b/platform/linux-generic/arch/arm/odp_cpu_arch.c
> index 2ac223e0..c31f9084 100644
> --- a/platform/linux-generic/arch/arm/odp_cpu_arch.c
> +++ b/platform/linux-generic/arch/arm/odp_cpu_arch.c
> @@ -13,6 +13,7 @@
> #include <odp/api/hints.h>
> #include <odp/api/system_info.h>
> #include <odp_debug_internal.h>
> +#include <odp_time_internal.h>
>
> #define GIGA 1000000000
>
> @@ -46,3 +47,18 @@ uint64_t odp_cpu_cycles_resolution(void)
> {
> return 1;
> }
> +
> +int cpu_has_global_time(void)
> +{
> + return 0;
> +}
> +
> +uint64_t cpu_global_time(void)
> +{
> + return 0;
> +}
> +
> +uint64_t cpu_global_time_freq(void)
> +{
> + return 0;
> +}
> diff --git a/platform/linux-generic/arch/default/odp_cpu_arch.c
> b/platform/linux-generic/arch/default/odp_cpu_arch.c
> index 2ac223e0..c31f9084 100644
> --- a/platform/linux-generic/arch/default/odp_cpu_arch.c
> +++ b/platform/linux-generic/arch/default/odp_cpu_arch.c
> @@ -13,6 +13,7 @@
> #include <odp/api/hints.h>
> #include <odp/api/system_info.h>
> #include <odp_debug_internal.h>
> +#include <odp_time_internal.h>
>
> #define GIGA 1000000000
>
> @@ -46,3 +47,18 @@ uint64_t odp_cpu_cycles_resolution(void)
> {
> return 1;
> }
> +
> +int cpu_has_global_time(void)
> +{
> + return 0;
> +}
> +
> +uint64_t cpu_global_time(void)
> +{
> + return 0;
> +}
> +
> +uint64_t cpu_global_time_freq(void)
> +{
> + return 0;
> +}
> diff --git a/platform/linux-generic/arch/mips64/odp_cpu_arch.c
> b/platform/linux-generic/arch/mips64/odp_cpu_arch.c
> index 646acf9c..f7eafa0f 100644
> --- a/platform/linux-generic/arch/mips64/odp_cpu_arch.c
> +++ b/platform/linux-generic/arch/mips64/odp_cpu_arch.c
> @@ -7,6 +7,7 @@
> #include <odp/api/cpu.h>
> #include <odp/api/hints.h>
> #include <odp/api/system_info.h>
> +#include <odp_time_internal.h>
>
> uint64_t odp_cpu_cycles(void)
> {
> @@ -29,3 +30,18 @@ uint64_t odp_cpu_cycles_resolution(void)
> {
> return 1;
> }
> +
> +int cpu_has_global_time(void)
> +{
> + return 0;
> +}
> +
> +uint64_t cpu_global_time(void)
> +{
> + return 0;
> +}
> +
> +uint64_t cpu_global_time_freq(void)
> +{
> + return 0;
> +}
> diff --git a/platform/linux-generic/arch/powerpc/odp_cpu_arch.c
> b/platform/linux-generic/arch/powerpc/odp_cpu_arch.c
> index 2ac223e0..c31f9084 100644
> --- a/platform/linux-generic/arch/powerpc/odp_cpu_arch.c
> +++ b/platform/linux-generic/arch/powerpc/odp_cpu_arch.c
> @@ -13,6 +13,7 @@
> #include <odp/api/hints.h>
> #include <odp/api/system_info.h>
> #include <odp_debug_internal.h>
> +#include <odp_time_internal.h>
>
> #define GIGA 1000000000
>
> @@ -46,3 +47,18 @@ uint64_t odp_cpu_cycles_resolution(void)
> {
> return 1;
> }
> +
> +int cpu_has_global_time(void)
> +{
> + return 0;
> +}
> +
> +uint64_t cpu_global_time(void)
> +{
> + return 0;
> +}
> +
> +uint64_t cpu_global_time_freq(void)
> +{
> + return 0;
> +}
> diff --git a/platform/linux-generic/arch/x86/cpu_flags.c
> b/platform/linux-generic/arch/x86/cpu_flags.c
> index 954dac27..a492a35b 100644
> --- a/platform/linux-generic/arch/x86/cpu_flags.c
> +++ b/platform/linux-generic/arch/x86/cpu_flags.c
> @@ -39,6 +39,7 @@
>
> #include <arch/x86/cpu_flags.h>
> #include <odp_debug_internal.h>
> +#include <odp_time_internal.h>
> #include <stdio.h>
> #include <stdint.h>
>
> @@ -357,3 +358,11 @@ void cpu_flags_print_all(void)
> str[len] = '\0';
> ODP_PRINT("%s", str);
> }
> +
> +int cpu_has_global_time(void)
> +{
> + if (cpu_get_flag_enabled(RTE_CPUFLAG_INVTSC) > 0)
> + return 1;
> +
> + return 0;
> +}
> diff --git a/platform/linux-generic/arch/x86/odp_cpu_arch.c
> b/platform/linux-generic/arch/x86/odp_cpu_arch.c
> index c8cf27b6..9ba601a3 100644
> --- a/platform/linux-generic/arch/x86/odp_cpu_arch.c
> +++ b/platform/linux-generic/arch/x86/odp_cpu_arch.c
> @@ -3,7 +3,14 @@
> *
> * SPDX-License-Identifier: BSD-3-Clause
> */
> +
> +#include <odp_posix_extensions.h>
> +
> #include <odp/api/cpu.h>
> +#include <odp_time_internal.h>
> +#include <odp_debug_internal.h>
> +
> +#include <time.h>
>
> uint64_t odp_cpu_cycles(void)
> {
> @@ -31,3 +38,55 @@ uint64_t odp_cpu_cycles_resolution(void)
> {
> return 1;
> }
> +
> +uint64_t cpu_global_time(void)
> +{
> + return odp_cpu_cycles();
> +}
> +
> +#define SEC_IN_NS 1000000000ULL
> +
> +/* Measure TSC frequency. Frequency information registers are defined for
> x86,
> + * but those are often not enumerated. */
> +uint64_t cpu_global_time_freq(void)
> +{
> + struct timespec sleep, ts1, ts2;
> + uint64_t t1, t2, ts_nsec, cycles, hz;
> + int i;
> + uint64_t avg = 0;
> + int rounds = 4;
> +
> + for (i = 0; i < rounds; i++) {
> + sleep.tv_sec = 0;
> + sleep.tv_nsec = SEC_IN_NS / 10;
> +
> + if (clock_gettime(CLOCK_MONOTONIC_RAW, &ts1)) {
> + ODP_DBG("clock_gettime failed\n");
> + return 0;
> + }
> +
> + t1 = cpu_global_time();
> +
> + if (nanosleep(&sleep, NULL) < 0) {
> + ODP_DBG("nanosleep failed\n");
> + return 0;
> + }
> +
> + if (clock_gettime(CLOCK_MONOTONIC_RAW, &ts2)) {
> + ODP_DBG("clock_gettime failed\n");
> + return 0;
> + }
> +
> + t2 = cpu_global_time();
> +
> + ts_nsec = (ts2.tv_sec - ts1.tv_sec) * SEC_IN_NS;
> + ts_nsec += ts2.tv_nsec - ts1.tv_nsec;
> +
> + cycles = t2 - t1;
> +
> + hz = (cycles * SEC_IN_NS) / ts_nsec;
> + avg += hz;
> + }
> +
> + return avg / rounds;
> +}
> diff --git a/platform/linux-generic/include/odp/api/plat/time_types.h
> b/platform/linux-generic/include/odp/api/plat/time_types.h
> index 4847f3b1..1cafb1f7 100644
> --- a/platform/linux-generic/include/odp/api/plat/time_types.h
> +++ b/platform/linux-generic/include/odp/api/plat/time_types.h
> @@ -26,11 +26,28 @@ extern "C" {
> * the linux timespec structure, which is dependent on POSIX extension level.
> */
> typedef struct odp_time_t {
> - int64_t tv_sec; /**< @internal Seconds */
> - int64_t tv_nsec; /**< @internal Nanoseconds */
> + union {
> + /** @internal Posix timespec */
> + struct {
> + /** @internal Seconds */
> + int64_t tv_sec;
> +
> + /** @internal Nanoseconds */
> + int64_t tv_nsec;
> + } spec;
> +
> + /** @internal HW time counter */
> + struct {
> + /** @internal Counter value */
> + uint64_t count;
> +
> + /** @internal Reserved */
> + uint64_t reserved;
> + } hw;
> + };
> } odp_time_t;
>
> -#define ODP_TIME_NULL ((odp_time_t){0, 0})
> +#define ODP_TIME_NULL ((odp_time_t){.spec = {0, 0} })
>
> /**
> * @}
> diff --git a/platform/linux-generic/include/odp_time_internal.h
> b/platform/linux-generic/include/odp_time_internal.h
> new file mode 100644
> index 00000000..99ac7977
> --- /dev/null
> +++ b/platform/linux-generic/include/odp_time_internal.h
> @@ -0,0 +1,24 @@
> +/* Copyright (c) 2017, Linaro Limited
> + * All rights reserved.
> + *
> + * SPDX-License-Identifier: BSD-3-Clause
> + */
> +
> +#ifndef ODP_TIME_INTERNAL_H_
> +#define ODP_TIME_INTERNAL_H_
> +
> +#ifdef __cplusplus
> +extern "C" {
> +#endif
> +
> +#include <stdint.h>
> +
> +int cpu_has_global_time(void);
> +uint64_t cpu_global_time(void);
> +uint64_t cpu_global_time_freq(void);
> +
> +#ifdef __cplusplus
> +}
> +#endif
> +
> +#endif
> diff --git a/platform/linux-generic/odp_time.c
> b/platform/linux-generic/odp_time.c
> index 0e5966c0..ac82175d 100644
> --- a/platform/linux-generic/odp_time.c
> +++ b/platform/linux-generic/odp_time.c
> @@ -10,36 +10,39 @@
> #include <odp/api/time.h>
> #include <odp/api/hints.h>
> #include <odp_debug_internal.h>
> +#include <odp_time_internal.h>
> +#include <string.h>
> +#include <inttypes.h>
>
> -static odp_time_t start_time;
> +typedef struct time_global_t {
> + odp_time_t start_time;
> + int use_hw;
> + uint64_t hw_start;
> + uint64_t hw_freq_hz;
> +} time_global_t;
>
> -static inline
> -uint64_t time_to_ns(odp_time_t time)
> -{
> - uint64_t ns;
> -
> - ns = time.tv_sec * ODP_TIME_SEC_IN_NS;
> - ns += time.tv_nsec;
> +static time_global_t global;
>
> - return ns;
> -}
> +/*
> + * Posix timespec based functions
> + */
>
> -static inline odp_time_t time_diff(odp_time_t t2, odp_time_t t1)
> +static inline odp_time_t time_spec_diff(odp_time_t t2, odp_time_t t1)
> {
> odp_time_t time;
>
> - time.tv_sec = t2.tv_sec - t1.tv_sec;
> - time.tv_nsec = t2.tv_nsec - t1.tv_nsec;
> + time.spec.tv_sec = t2.spec.tv_sec - t1.spec.tv_sec;
> + time.spec.tv_nsec = t2.spec.tv_nsec - t1.spec.tv_nsec;
>
> - if (time.tv_nsec < 0) {
> - time.tv_nsec += ODP_TIME_SEC_IN_NS;
> - --time.tv_sec;
> + if (time.spec.tv_nsec < 0) {
> + time.spec.tv_nsec += ODP_TIME_SEC_IN_NS;
> + --time.spec.tv_sec;
> }
>
> return time;
> }
>
> -static inline odp_time_t time_local(void)
> +static inline odp_time_t time_spec_cur(void)
> {
> int ret;
> odp_time_t time;
> @@ -49,77 +52,234 @@ static inline odp_time_t time_local(void)
> if (odp_unlikely(ret != 0))
> ODP_ABORT("clock_gettime failed\n");
>
> - time.tv_sec = sys_time.tv_sec;
> - time.tv_nsec = sys_time.tv_nsec;
> + time.spec.tv_sec = sys_time.tv_sec;
> + time.spec.tv_nsec = sys_time.tv_nsec;
>
> - return time_diff(time, start_time);
> + return time_spec_diff(time, global.start_time);
> }
>
> -static inline int time_cmp(odp_time_t t2, odp_time_t t1)
> +static inline uint64_t time_spec_res(void)
> {
> - if (t2.tv_sec < t1.tv_sec)
> + int ret;
> + struct timespec tres;
> +
> + ret = clock_getres(CLOCK_MONOTONIC_RAW, &tres);
> + if (odp_unlikely(ret != 0))
> + ODP_ABORT("clock_getres failed\n");
> +
> + return ODP_TIME_SEC_IN_NS / (uint64_t)tres.tv_nsec;
> +}
> +
> +static inline int time_spec_cmp(odp_time_t t2, odp_time_t t1)
> +{
> + if (t2.spec.tv_sec < t1.spec.tv_sec)
> return -1;
>
> - if (t2.tv_sec > t1.tv_sec)
> + if (t2.spec.tv_sec > t1.spec.tv_sec)
> return 1;
>
> - return t2.tv_nsec - t1.tv_nsec;
> + return t2.spec.tv_nsec - t1.spec.tv_nsec;
> }
>
> -static inline odp_time_t time_sum(odp_time_t t1, odp_time_t t2)
> +static inline odp_time_t time_spec_sum(odp_time_t t1, odp_time_t t2)
> {
> odp_time_t time;
>
> - time.tv_sec = t2.tv_sec + t1.tv_sec;
> - time.tv_nsec = t2.tv_nsec + t1.tv_nsec;
> + time.spec.tv_sec = t2.spec.tv_sec + t1.spec.tv_sec;
> + time.spec.tv_nsec = t2.spec.tv_nsec + t1.spec.tv_nsec;
>
> - if (time.tv_nsec >= (long)ODP_TIME_SEC_IN_NS) {
> - time.tv_nsec -= ODP_TIME_SEC_IN_NS;
> - ++time.tv_sec;
> + if (time.spec.tv_nsec >= (long)ODP_TIME_SEC_IN_NS) {
> + time.spec.tv_nsec -= ODP_TIME_SEC_IN_NS;
> + ++time.spec.tv_sec;
> }
>
> return time;
> }
>
> -static inline odp_time_t time_local_from_ns(uint64_t ns)
> +static inline uint64_t time_spec_to_ns(odp_time_t time)
> +{
> + uint64_t ns;
> +
> + ns = time.spec.tv_sec * ODP_TIME_SEC_IN_NS;
> + ns += time.spec.tv_nsec;
> +
> + return ns;
> +}
> +
> +static inline odp_time_t time_spec_from_ns(uint64_t ns)
> {
> odp_time_t time;
>
> - time.tv_sec = ns / ODP_TIME_SEC_IN_NS;
> - time.tv_nsec = ns - time.tv_sec * ODP_TIME_SEC_IN_NS;
> + time.spec.tv_sec = ns / ODP_TIME_SEC_IN_NS;
> + time.spec.tv_nsec = ns - time.spec.tv_sec * ODP_TIME_SEC_IN_NS;
>
> return time;
> }
>
> -static inline void time_wait_until(odp_time_t time)
> +/*
> + * HW time counter based functions
> + */
> +
> +static inline odp_time_t time_hw_cur(void)
> {
> - odp_time_t cur;
> + odp_time_t time;
>
> - do {
> - cur = time_local();
> - } while (time_cmp(time, cur) > 0);
> + time.hw.count = cpu_global_time() - global.hw_start;
Computing the offset is unnecessarily expensive. The simplest and lowest
overhead solution is to just store the value read from HW and convert
at a later point in time. But, this no longer represents what odp_time_t
represents. That is why I introduced odp_tick_t in the timer RFC and
design doc posted to the list *several* times.
> +
> + return time;
> }
>
> -static inline uint64_t time_local_res(void)
> +static inline uint64_t time_hw_res(void)
> {
> - int ret;
> - struct timespec tres;
> + /* Promise a bit lower resolution than average cycle counter
> + * frequency */
> + return global.hw_freq_hz / 10;
> +}
>
> - ret = clock_getres(CLOCK_MONOTONIC_RAW, &tres);
> - if (odp_unlikely(ret != 0))
> - ODP_ABORT("clock_getres failed\n");
> +static inline int time_hw_cmp(odp_time_t t2, odp_time_t t1)
> +{
> + if (odp_likely(t2.hw.count > t1.hw.count))
> + return 1;
>
> - return ODP_TIME_SEC_IN_NS / (uint64_t)tres.tv_nsec;
> + if (t2.hw.count < t1.hw.count)
> + return -1;
> +
> + return 0;
> +}
> +
> +static inline odp_time_t time_hw_diff(odp_time_t t2, odp_time_t t1)
> +{
> + odp_time_t time;
> +
> + time.hw.count = t2.hw.count - t1.hw.count;
> +
> + return time;
> +}
> +
> +static inline odp_time_t time_hw_sum(odp_time_t t1, odp_time_t t2)
> +{
> + odp_time_t time;
> +
> + time.hw.count = t1.hw.count + t2.hw.count;
> +
> + return time;
> +}
> +
> +static inline uint64_t time_hw_to_ns(odp_time_t time)
> +{
> + uint64_t nsec;
> + uint64_t freq_hz = global.hw_freq_hz;
> + uint64_t count = time.hw.count;
> + uint64_t sec = 0;
> +
> + if (count >= freq_hz) {
> + sec = count / freq_hz;
> + count = count - sec * freq_hz;
> + }
> +
> + nsec = (ODP_TIME_SEC_IN_NS * count) / freq_hz;
> +
> + return (sec * ODP_TIME_SEC_IN_NS) + nsec;
> +}
> +
> +static inline odp_time_t time_hw_from_ns(uint64_t ns)
> +{
> + odp_time_t time;
> + uint64_t count;
> + uint64_t freq_hz = global.hw_freq_hz;
> + uint64_t sec = 0;
> +
> + if (ns >= ODP_TIME_SEC_IN_NS) {
> + sec = ns / ODP_TIME_SEC_IN_NS;
> + ns = ns - sec * ODP_TIME_SEC_IN_NS;
> + }
> +
> + count = sec * freq_hz;
> + count += (ns * freq_hz) / ODP_TIME_SEC_IN_NS;
> +
> + time.hw.reserved = 0;
> + time.hw.count = count;
> +
> + return time;
> +}
> +
> +/*
> + * Common functions
> + */
> +
> +static inline odp_time_t time_cur(void)
> +{
> + if (global.use_hw)
> + return time_hw_cur();
> +
> + return time_spec_cur();
> +}
> +
> +static inline uint64_t time_res(void)
> +{
> + if (global.use_hw)
> + return time_hw_res();
> +
> + return time_spec_res();
> +}
> +
> +static inline int time_cmp(odp_time_t t2, odp_time_t t1)
> +{
> + if (global.use_hw)
> + return time_hw_cmp(t2, t1);
> +
> + return time_spec_cmp(t2, t1);
> +}
> +
> +static inline odp_time_t time_diff(odp_time_t t2, odp_time_t t1)
> +{
> + if (global.use_hw)
> + return time_hw_diff(t2, t1);
> +
> + return time_spec_diff(t2, t1);
> +}
> +
> +static inline odp_time_t time_sum(odp_time_t t1, odp_time_t t2)
> +{
> + if (global.use_hw)
> + return time_hw_sum(t1, t2);
> +
> + return time_spec_sum(t1, t2);
> +}
> +
> +static inline uint64_t time_to_ns(odp_time_t time)
> +{
> + if (global.use_hw)
> + return time_hw_to_ns(time);
> +
> + return time_spec_to_ns(time);
> +}
> +
> +static inline odp_time_t time_from_ns(uint64_t ns)
> +{
> + if (global.use_hw)
> + return time_hw_from_ns(ns);
> +
> + return time_spec_from_ns(ns);
> +}
> +
> +static inline void time_wait_until(odp_time_t time)
> +{
> + odp_time_t cur;
> +
> + do {
> + cur = time_cur();
> + } while (time_cmp(time, cur) > 0);
> }
>
> odp_time_t odp_time_local(void)
> {
> - return time_local();
> + return time_cur();
> }
>
> odp_time_t odp_time_global(void)
> {
> - return time_local();
> + return time_cur();
> }
>
> odp_time_t odp_time_diff(odp_time_t t2, odp_time_t t1)
> @@ -134,12 +294,12 @@ uint64_t odp_time_to_ns(odp_time_t time)
>
> odp_time_t odp_time_local_from_ns(uint64_t ns)
> {
> - return time_local_from_ns(ns);
> + return time_from_ns(ns);
> }
>
> odp_time_t odp_time_global_from_ns(uint64_t ns)
> {
> - return time_local_from_ns(ns);
> + return time_from_ns(ns);
> }
>
> int odp_time_cmp(odp_time_t t2, odp_time_t t1)
> @@ -154,18 +314,18 @@ odp_time_t odp_time_sum(odp_time_t t1, odp_time_t t2)
>
> uint64_t odp_time_local_res(void)
> {
> - return time_local_res();
> + return time_res();
> }
>
> uint64_t odp_time_global_res(void)
> {
> - return time_local_res();
> + return time_res();
> }
>
> void odp_time_wait_ns(uint64_t ns)
> {
> - odp_time_t cur = time_local();
> - odp_time_t wait = time_local_from_ns(ns);
> + odp_time_t cur = time_cur();
> + odp_time_t wait = time_from_ns(ns);
> odp_time_t end_time = time_sum(cur, wait);
>
> time_wait_until(end_time);
> @@ -178,15 +338,31 @@ void odp_time_wait_until(odp_time_t time)
>
> int odp_time_init_global(void)
> {
> - int ret;
> - struct timespec time;
> -
> - ret = clock_gettime(CLOCK_MONOTONIC_RAW, &time);
> - if (ret) {
> - start_time = ODP_TIME_NULL;
> - } else {
> - start_time.tv_sec = time.tv_sec;
> - start_time.tv_nsec = time.tv_nsec;
> + struct timespec sys_time;
> + int ret = 0;
> +
> + memset(&global, 0, sizeof(time_global_t));
> +
> + if (cpu_has_global_time()) {
> + global.use_hw = 1;
> + global.hw_freq_hz = cpu_global_time_freq();
> +
> + if (global.hw_freq_hz == 0)
> + return -1;
> +
> + printf("HW time counter freq: %" PRIu64 " hz\n\n",
> + global.hw_freq_hz);
> +
> + global.hw_start = cpu_global_time();
> + return 0;
> + }
> +
> + global.start_time = ODP_TIME_NULL;
> +
> + ret = clock_gettime(CLOCK_MONOTONIC_RAW, &sys_time);
> + if (ret == 0) {
> + global.start_time.spec.tv_sec = sys_time.tv_sec;
> + global.start_time.spec.tv_nsec = sys_time.tv_nsec;
> }
>
> return ret;
> --
> 2.11.0
>
