wait_for_com...n_io_timeout(9)

💅 wait_for_completion_io_timeout(9) — Kernel API Manual 💅

okay bestie, this is the Kernel API Manual page for wait_for_completion_io_timeout. The header keeps it abbreviated as wait_for_com...n_io_timeout(9) — iconic truncation, honestly 💖

🌸 NAME 🌸

wait_for_completion_io_timeout — the NAME line says wait_for_completion_io_timeout - - waits for completion of a task (w/timeout) 💅

✨ SYNOPSIS ✨

unsigned long wait_for_completion_io_timeout (struct completion *x ,
unsigned long timeout );

🫶 ARGUMENTS 🫶

• x — holds the state of this particular completion 🎀
• timeout — timeout value in jiffies ⏰

💖 DESCRIPTION 💖

So here’s the vibe: this waits for either a completion of a specific task to be signaled or for a specified timeout to expire. The timeout is in jiffies — that’s the unit, bestie ✨

It is not interruptible — no tap-outs, periodt 💀

The caller is accounted as waiting for IO (which traditionally means blkio only). That’s the accounting detail, iykyk 🦋

🎀 RETURN 🎀

• 0 — if timed out 😭
• positive (at least 1, or number of jiffies left till timeout) — if completed 🎉👑

🦋 SEE ALSO 🦋

Kernel file ./kernel/sched/completion.c — go peek, bestie:

• complete(9)
• complete_all(9)
• wait_for_completion(9)
• wait_for_completion_timeout(9)
• wait_for_completion_io(9)
• wait_for_completion_interruptible(9)
• wait_for_completion_interruptible_timeout(9)
• wait_for_completion_killable(9)
• wait_for_completion_killable_timeout(9)
• try_wait_for_completion(9)
• completion_done(9)

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💜 that’s the whole page, bestie — source/version spot is ./kernel/sched, dated October 2026, and the footer page tag is wait_for_com...n_io_timeout(9). mwah 💋