tick_nohz_update_jiffies(9)

✨ NAME ✨

tick_nohz_update_jiffies(9) from the Kernel API Manual — literally here to update jiffies when idle got interrupted 💅✨

🌸 SYNOPSIS 🌸

void tick_nohz_update_jiffies (ktime_t now );

🎀 ARGUMENTS 🎀

• now — the current ktime_t, bestie ⏰🫶

🦋 DESCRIPTION 🦋

Okay so this one gets called from interrupt entry when the CPU was idle 😴✨

So if the sched_tick was stopped on this CPU, we have to check whether jiffies must be updated. Otherwise an interrupt handler could use a stale jiffy value 😭 — and that is not the vibe.

We do this unconditionally on any CPU, because we don't know whether the CPU that has the update task assigned is in a long sleep 😴💀 no cap, we're not out here guessing.

🔥 SEE ALSO 🔥

Kernel file ./kernel/time/tick-sched.c plus these iconic functions, iykyk:

• tick_nohz_next_event(9)
• tick_nohz_idle_stop_tick(9)
• tick_nohz_idle_enter(9)
• tick_nohz_irq_exit(9)
• tick_nohz_idle_got_tick(9)
• tick_nohz_get_next_hrtimer(9)
• tick_nohz_get_sleep_length(9)
• tick_nohz_get_idle_calls_cpu(9)
• tick_nohz_idle_exit(9)
• tick_nohz_switch_to_nohz(9)
• tick_setup_sched_timer(9)

And that's the whole page, bestie! Source/version is ./kernel/time and the date is October 2026, so this sign-off is giving tick_nohz_update_jiffies(9) with main character energy 👑💖🎀