get_order(9)

get_order(9) 💅

okay bestie, welcome to the Kernel API Manual page for get_order — yes, the function name is literally the whole vibe. It's here to tell you the allocation order for a memory size, and we're gonna get into it.

✨ NAME ✨

get_order — determine the allocation order of a memory size 💖

🎀 SYNOPSIS 🎀

int get_order (unsigned long size );

🦋 ARGUMENTS 🦋

• size — the size for which you want to get the order. That's the whole input, bestie; hand it a size and it does its little logarithmic thing. 🫶

🔥 DESCRIPTION 🔥

so get_order determines the allocation order of a particular sized block of memory. It's on a logarithmic scale, and the mapping is giving:

• 0 -> 2^0 * PAGE_SIZE and below
• 1 -> 2^1 * PAGE_SIZE to 2^0 * PAGE_SIZE + 1
• 2 -> 2^2 * PAGE_SIZE to 2^1 * PAGE_SIZE + 1
• 3 -> 2^3 * PAGE_SIZE to 2^2 * PAGE_SIZE + 1
• 4 -> 2^4 * PAGE_SIZE to 2^3 * PAGE_SIZE + 1
• ...

The order that comes back is used to find the smallest allocation granule required to hold an object of the specified size. Very "smallest container that fits the fit" energy. 🎀

⚠️ heads up, bestie: the result is undefined if the size is 0. Not "zero-ish", not "tiny", literally undefined. Don't do it. 💀

🌈 SEE ALSO 🌈

• Kernel file ./include/asm-generic/getorder.h 📁

and that's the page, periodt. this cutie is sourced from ./include/asm-generic, dated October 2026, and it's serving get_order(9) realness. 💖✨