blk_cgroup_congested(9)

🎀 NAME 🎀

okay bestie, welcome to blk_cgroup_congested(9) from the Kernel API Manual — the whole vibe here is answering: is the current task in a throttled blkcg? 👀💅

✨ SYNOPSIS ✨

bool blk_cgroup_congested (void );

🫶 ARGUMENTS 🫶

• void — no arguments, bestie. zero. nada. the function takes nothing 🎀

💖 DESCRIPTION 💖

so this one gets called from mm hot paths, where the answer is almost always false 😭. because of that, the move is to keep that case down to a load and a branch — super cheap, no drama — and only walk the hierarchy out of line when something in the system really is throttled. it's giving optimized-for-the-common-case, fr fr ✨

🦋 RETURN 🦋

• true — if the current task's blkcg or any of its ancestors is throttled 👑
• false — otherwise 💀

🌈 SEE ALSO 🌈

• Kernel file ./include/linux/blk-cgroup.h — go read it, iykyk 📚💜

okay that's the whole page, bestie 🫶 this cutie comes from ./include/linux, dated October 2026 — mwah 💋✨