relay_write(9)

💅 relay_write(9) — aka the Kernel API Manual, bestie edition ✨

Okay so like, hi, welcome to relay_write(9) from the Kernel API Manual 🎀 — this is the function you call when you literally just want your data to end up in the relay channel and you're not tryna overthink it. Let's get into it 🦋

✨ NAME ✨

relay_write — write data into the channel 💫

🌸 SYNOPSIS 🌸

void relay_write (struct rchan *chan , const void *data , size_t length );

💖 ARGUMENTS 💖

• chan — the relay channel, obvi 🫶
• data — the actual data to be written, the main character of this whole operation 👑
• length — number of bytes to write, so like, how much of data we're serving up 🍓

🔥 DESCRIPTION 🔥

Writes data into the current cpu's channel buffer. That's it, that's the vibe ✨

It protects the buffer by disabling interrupts 🛡️ — so slay, no cap, your buffer stays safe.

Use this if you might be logging from interrupt context 👀 because that's literally the whole point of the interrupt-disabling protection. But if you know you won't be logging from interrupt context, then try __relay_write instead — she's the lighter-weight option, iykyk 💅

bestie pls note: the interrupt-disabling is doing real work here, so don't just casually swap in __relay_write unless you're 100% sure about your context fr fr 😭

🦋 SEE ALSO 🦋

Kernel file ./include/linux/relay.h — plus __relay_write(9), relay_reserve(9), and subbuf_start_reserve(9) 💜

and that's the whole page, mwah 💋 — this lil icon dropped from ./include/linux, dated October 2026, and it's the relay_write(9) page itself signing off 🧚🌸 go forth and log responsibly bestie ✨