blkg_tryget_closest(9)

🎀 blkg_tryget_closest(9) 🎀

okay bestie, welcome to the Kernel API Manual page for blkg_tryget_closest(9) — yes, that's the whole title vibe, and we're gonna get through it together 💖

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💖 NAME 💖

blkg_tryget_closest — “try and get a blkg ref on the closet blkg.” The page literally says “closet” and I'm not fixing it, that's iconic 💅

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✨ SYNOPSIS ✨

Here's the signature, copied exactly because we do not mess with code in this group chat:

struct blkcg_gq * blkg_tryget_closest (struct bio *bio , struct
cgroup_subsys_state *css );

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🧸 ARGUMENTS 🧸

• bio — the target bio, aka the bio we're aiming at 🎯
• css — the target css, simple as that ✨

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💫 DESCRIPTION 💫

So the failure mode here is that we walk up the blkg tree, and because of that, this makes sure the blkg->parent pointers are always valid. No stale-parent nonsense, periodt 🫶

It returns the blkg it ended up taking a reference on — or NULL if no reference was taken. That's the whole deal, bestie 💖

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🌈 SEE ALSO 🌈

Kernel file: ./block/blk-cgroup.c — and here's the whole squad, every single one, no skips:

• blkcg_css(9)
• blkg_free(9)
• bio_blkcg_css(9)
• blkcg_parent(9)
• blkg_alloc(9)
• blkg_lookup_create(9)
• blkcg_print_blkgs(9)
• __blkg_prfill_u64(9)
• blkg_conf_init(9)
• blkg_conf_open_bdev(9)
• blkg_conf_prep(9)
• blkg_conf_unprep(9)
• blkg_conf_close_bdev(9)
• blkcg_destroy_blkgs(9)
• blkcg_pin_online(9)
• blkcg_unpin_online(9)
• blkcg_css_offline(9)
• blkcg_activate_policy(9)
• blkcg_deactivate_policy(9)
• blkcg_policy_register(9)
• blkcg_policy_unregister(9)
• blkcg_maybe_throttle_current(9)
• blkcg_schedule_throttle(9)
• blkcg_add_delay(9)
• bio_associate_blkg_from_css(9)
• bio_associate_blkg(9)
• bio_clone_blkg_association(9)

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mwah 💋 that's the page, bestie! It comes from source/version ./block, dated October 2026, and it's all about blkg_tryget_closest(9). slay and goodbye 🫶✨