zx_ticks_get_boot

Summary

Read the number of high-precision timer ticks since boot, including any time spent in a suspended state.

Declaration

#include <zircon/syscalls.h>

zx_instant_boot_ticks_t zx_ticks_get_boot(void);

Description

zx_ticks_get_boot() returns the number of high-precision timer ticks since boot, including any time spent in a suspended state.

These ticks may be processor cycles, high speed timer, profiling timer, etc.

Rights

None.

Return value

zx_ticks_get_boot() returns the number of high-precision timer ticks since boot.

Errors

zx_ticks_get_boot() does not report any error conditions.

Notes

The returned value may be highly variable. Factors that can affect it include:

Reset of the processor cycle counter
Reordering of instructions (if required, use a memory barrier)

All Fuchsia systems use an invariant-rate ticks clock, which means that the number of ticks per second is constant regardless of changes in processor speed or migration between processors.