michaelh/zephyr
1
0
Fork 0
Code Releases Activity

kernel: Deprecate sys_clock_us_per_tick variable.

Browse source 
On some architectures tick time cannot be expressed as integer
number of microseconds, introducing error in calculations using
sys_clock_us_per_tick variable.

This commit deprecates the sys_clock_us_per_tick variable and
replaces its usage by more precise calculations based on
sys_clock_hw_cycles_per_sec and sys_clock_ticks_per_sec.

Signed-off-by: Piotr Zięcik <piotr.ziecik@nordicsemi.no>
This commit is contained in:
Piotr Zięcik 2018-07-17 15:14:32 +02:00 • committed by Anas Nashif
commit 2fe998cdef
7 changed files with 14 additions and 14 deletions
Download patch file Download diff file Expand all files Collapse all files

5
drivers/timer/hpet.c
View file

@ -580,11 +580,10 @@ int _sys_clock_driver_init(struct device *device)
*/
/*
* Convert the 'sys_clock_us_per_tick' value
* from microseconds to femptoseconds
* Get tick time (in femptoseconds).
*/
tickFempto = (u64_t)sys_clock_us_per_tick * 1000000000;
tickFempto = 1000000000000000ull / sys_clock_ticks_per_sec;
/*
* This driver shall read the COUNTER_CLK_PERIOD value from the general

2
drivers/timer/native_posix_timer.c
View file

@ -103,7 +103,7 @@ int _sys_clock_driver_init(struct device *device)
{
ARG_UNUSED(device);
tick_period = sys_clock_us_per_tick;
tick_period = 1000000ul / sys_clock_ticks_per_sec;
hwtimer_enable(tick_period);

8
include/sys_clock.h
View file

@ -21,6 +21,7 @@ extern "C" {
#endif
#ifndef _ASMLANGUAGE
#include <toolchain.h>
#include <zephyr/types.h>
#if defined(CONFIG_SYS_CLOCK_EXISTS) && \
@ -46,8 +47,10 @@ extern int sys_clock_hw_cycles_per_sec;
/*
* sys_clock_us_per_tick global variable represents a number
* of microseconds in one OS timer tick
*
* Note: This variable is deprecated and will be removed soon!
*/
extern int sys_clock_us_per_tick;
__deprecated extern int sys_clock_us_per_tick;
/*
* sys_clock_hw_cycles_per_tick global variable represents a number
@ -75,8 +78,7 @@ extern int sys_clock_hw_cycles_per_tick;
/* SYS_CLOCK_HW_CYCLES_TO_NS64 converts CPU clock cycles to nanoseconds */
#define SYS_CLOCK_HW_CYCLES_TO_NS64(X) \
(((u64_t)(X) * sys_clock_us_per_tick * NSEC_PER_USEC) / \
sys_clock_hw_cycles_per_tick)
(((u64_t)(X) * NSEC_PER_SEC) / sys_clock_hw_cycles_per_sec)
/*
* SYS_CLOCK_HW_CYCLES_TO_NS_AVG converts CPU clock cycles to nanoseconds

8
samples/net/zperf/src/zperf_internal.h
View file

@ -30,8 +30,8 @@
#define HW_CYCLES_TO_USEC(__hw_cycle__) \
( \
((u64_t)(__hw_cycle__) * (u64_t)sys_clock_us_per_tick) / \
((u64_t)sys_clock_hw_cycles_per_tick) \
((u64_t)(__hw_cycle__) * (u64_t)USEC_PER_SEC) / \
((u64_t)sys_clock_hw_cycles_per_sec) \
)
#define HW_CYCLES_TO_SEC(__hw_cycle__) \
@ -42,8 +42,8 @@
#define USEC_TO_HW_CYCLES(__usec__) \
( \
((u64_t)(__usec__) * (u64_t)sys_clock_hw_cycles_per_tick) / \
((u64_t)sys_clock_us_per_tick) \
((u64_t)(__usec__) * (u64_t)sys_clock_hw_cycles_per_sec) / \
((u64_t)USEC_PER_SEC) \
)
#define SEC_TO_HW_CYCLES(__sec__) \

2
tests/kernel/context/src/main.c
View file

@ -245,7 +245,7 @@ static void _test_kernel_cpu_idle(int atomic)
k_cpu_idle();
}
/* calculating milliseconds per tick*/
tms += sys_clock_us_per_tick / USEC_PER_MSEC;
tms += __ticks_to_ms(1);
tms2 = k_uptime_get_32();
zassert_false(tms2 < tms, "Bad ms per tick value computed,"
"got %d which is less than %d\n",

2
tests/kernel/tickless/tickless_concept/src/main.c
View file

@ -16,7 +16,7 @@ static struct k_thread tdata[NUM_THREAD];
#define CONFIG_TICKLESS_IDLE_THRESH 20
#endif
/*millisecond per tick*/
#define MSEC_PER_TICK (sys_clock_us_per_tick / USEC_PER_MSEC)
#define MSEC_PER_TICK (__ticks_to_ms(1))
/*sleep duration tickless*/
#define SLEEP_TICKLESS (CONFIG_TICKLESS_IDLE_THRESH * MSEC_PER_TICK)
/*sleep duration with tick*/

1
tests/kernel/timer/timer_monotonic/src/main.c
View file

@ -54,7 +54,6 @@ void test_timer(void)
errors = 0;
TC_PRINT("sys_clock_us_per_tick = %d\n", sys_clock_us_per_tick);
TC_PRINT("sys_clock_hw_cycles_per_tick = %d\n",
sys_clock_hw_cycles_per_tick);
TC_PRINT("sys_clock_hw_cycles_per_sec = %d\n",