__bfq_bic_change_cgroup(9)

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

okay bestie, welcome to the Kernel API Manual entry for __bfq_bic_change_cgroup — she's a void-returning queen with three struct pointers and zero chill. let's get into it ✨

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🌸 NAME 🌸

__bfq_bic_change_cgroup — move @bic to @bfqg.

that's it. that's the whole name. she does one thing and she does it slayfully 💅

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✨ SYNOPSIS ✨

void __bfq_bic_change_cgroup (struct bfq_data *bfqd , struct bfq_io_cq
*bic , struct bfq_group *bfqg );

like, look at her. returns nothing (void, she gives nothing back, main character energy fr), takes three args, and she's not sorry about it 😌

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🦋 ARGUMENTS 🦋

• bfqd — the queue descriptor. literally the queue's whole personality in one struct.
• bic — the bic to move. she's the one getting relocated, bestie 🚚
• bfqg — the group to move to. her new home. new cgroup, new me 🏡

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🫶 DESCRIPTION 🫶

so what she actually does: she moves bic to blkcg, and she assumes that bfqd->lock is held. and like — that's not a suggestion, okay? that assumption is the whole reason the reference to the cgroup stays valid across the call 🫶

⚠️ fr fr, the bfqd->lock-held thing matters: it's what makes sure the cgroup reference stays valid for the entire call. don't be the one who forgets the lock 💀

and if you want the full lore on why that matters, the original says to see the comments in bfq_bic_update_cgroup on this issue. go read the comments, bestie, they ate 👑

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💜 SEE ALSO 💜

• Kernel file ./block/bfq-cgroup.c — the source file, the origin story, the blueprint 🧚
• bfq_stat_add(9)
• bfq_stat_read(9)
• bfq_stat_reset(9)
• bfq_stat_add_aux(9)
• blkg_prfill_stat(9)
• bfq_bfqq_move(9)
• bfq_flush_idle_tree(9)
• bfq_reparent_leaf_entity(9)
• bfq_reparent_active_queues(9)
• bfq_pd_offline(9)

that's the whole friend group. say hi to all of them for me 🌈

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okay that's the page!! sourced from ./block, dated October 2026, and no cap it's giving iconic kernel documentation 💖 stay locked (bfqd->lock, obviously), stay valid, and I'll see you in the next manpage. mwah 🍓💜