ct_idle_exit(9)

🌸 NAME 🌸

okay so bestie, this is ct_idle_exit(9) from the Kernel API Manual — the little function that goes “hey RCU, this CPU is leaving idle” 💅✨.

• ct_idle_exit — informs RCU that current CPU is leaving idle. iconic, concise, no cap.

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🦋 SYNOPSIS 🦋

void noinstr ct_idle_exit (void );

copy it exactly, character for character — the noinstr stays, bestie 🫶

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🎀 ARGUMENTS 🎀

• void — no arguments. literally zero. nothing. the function said “no thoughts, head empty” 💀✨

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💜 DESCRIPTION 💜

okay so what it does: it exits idle mode — in other words, you’re -enter-ing the mode in which RCU read-side critical sections can occur. main character energy for the RCU girlies 🌈

🚨 bestie warning: if you add or remove a call to ct_idle_exit, be sure to test with CONFIG_RCU_EQS_DEBUG=y. no skipping this, fr fr.

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🔥 SEE ALSO 🔥

Kernel file ./kernel/context_tracking.c is right there holding it down, and these are the besties you should also check out:

• ct_nmi_exit(9)
• ct_nmi_enter(9)
• ct_idle_enter(9)
• ct_irq_enter(9)
• ct_irq_exit(9)
• __ct_user_enter(9)
• user_enter_callable(9)
• __ct_user_exit(9)
• user_exit_callable(9)

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mwah 💋 — source/version: ./kernel; date: October 2026; page: ct_idle_exit(9). that’s the whole thing, go slay your kernel work 🫶✨