css_rstat_push_children(9)

💅 css_rstat_push_children(9) — a Kernel API Manual moment 🎀

okay bestie, this one's from the Kernel API Manual and it's lowkey a whole vibe ✨ it's css_rstat_push_children, and no cap it does exactly one thing but it does it well 🫶

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✨ NAME ✨

css_rstat_push_children — push children css's into the given list 💖 (yes that's the whole name, she's not wordy, she's efficient 👑)

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🌸 SYNOPSIS 🌸

struct cgroup_subsys_state * css_rstat_push_children (struct
cgroup_subsys_state *head , struct cgroup_subsys_state *child , int cpu
);

like, that's the whole signature. struct in, struct out, three args, periodt 💅

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🦋 ARGUMENTS 🦋

• head — the current head of the list (which also = the subtree root, iykyk 🌈)
• child — the first child of the root, aka where the walk starts 👶
• cpu — the target cpu. the one we're doing all this for 🖥️

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⭐ RETURN ⭐

A new singly linked list of css's to be flushed. that's it, that's the tea ☕ she hands you back a whole list and you're like "slay" 💀

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💜 DESCRIPTION 💜

okay so here's the lore 🔥 the function iteratively traverses down the css_rstat_cpu updated tree, level by level, and pushes all the parents first before their next-level children into a singly linked list. the connection goes through the rstat_flush_next pointer, and the list is built from the tail backward, like "pushing" css's into a stack 🥞 (yes, literally a stack, she said what she said).

and literally the root? the caller pushes that one, not this function. not her job, not her problem 🙈

fr fr remember: the root is pushed by the caller. don't come for this function about the root, she doesn't know her 💀

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🧚 SEE ALSO 🧚

• Kernel file ./kernel/cgroup/rstat.c
• __css_rstat_updated(9)
• css_rstat_updated_list(9)
• css_rstat_flush(9)
• ss_rstat_init(9)

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that's the page bestie, go forth and push some children 🌸🫶

sign-off szn: this one lives under ./kernel/cgroup and it's dated October 2026 — iconic, timeless, we stan a stable release calendar 👑💖