d8b4d53444
Fix the issue where clock_gettime(CLOCK_MONOTONIC) always returns 0 in
tickless mode, caused by the scheduler tick counter (g_system_ticks) not
being updated with the actual timer ticks.
1. Add clock_update_sched_ticks() function to sched/clock/clock_sched_ticks.c:
a. This function directly sets the system tick counter to a specific value
(vs incrementing in clock_increase_sched_ticks), with full documentation
matching the existing code style.
b. Uses seqlock to ensure thread-safe access to g_system_ticks.
2. Call clock_update_sched_ticks() in nxsched_process_timer() (sched_processtickless.c):
a. Syncs the scheduler tick counter with the actual timer ticks retrieved via up_timer_gettick().
With this fix, g_system_ticks is properly updated in tickless mode,
and clock_gettime(CLOCK_MONOTONIC) returns the correct non-zero monotonic time.
Signed-off-by: chao an <anchao.archer@bytedance.com>
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