blk_stat_free_callback(9)

💅 blk_stat_free_callback (kernel API manual)

okay so bestie, we're in blk_stat_free_callback(9) territory — section 9, kernel API manual, the land of people who write drivers for fun (iconic behavior honestly). this one's short and sweet: it's the little cleanup baddie that frees a block statistics callback. let's get into it ✨

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🌸 NAME 🌸

blk_stat_free_callback — free a block statistics callback. that's it. that's the whole vibe check. 🎀

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✨ SYNOPSIS ✨

void blk_stat_free_callback (struct blk_stat_callback *cb );

no return value, no drama, just vibes and a pointer. 💅

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🦋 ARGUMENTS 🦋

• cb — the callback. yes, that's the entire description. she's simple, she's the main character, she's the callback. 🫶

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🔥 DESCRIPTION 🔥

okay so here's the tea, bestie, and you need to hear it:

• cb may be NULL, and if it is, this function literally does nothing. no cap, zero effort, it just vibes. 😌
• if cb is not NULL, then cb must not be associated with a request queue. like, at all. read that again. 🙈

and what does "must not be associated with a request queue" actually mean in practice? i'm so glad you asked:

if cb was previously added with blk_stat_add_callback, it must also have been removed since then with blk_stat_remove_callback. both. in that order. no skipping steps, no shortcuts. periodt. 💀

so yeah — free it after you've un-added it. that's the whole rule. it's giving "clean up your room before you move out" energy. 🧚

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⭐ SEE ALSO ⭐

bestie you're gonna wanna know the whole friend group, so here's the squad:

• Kernel file ./block/blk-stat.h struct blk_stat_callback(9)
• blk_stat_alloc_callback(9)
• blk_stat_add_callback(9)
• blk_stat_remove_callback(9)
• blk_stat_is_active(9)
• blk_stat_activate_nsecs(9)
• blk_stat_activate_msecs(9)

iykyk 💖

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and that's the page, bestie!! this lil icon lives in ./block, dated October 2026, and she's officially titled blk_stat_free_callback(9) — go free those callbacks responsibly, mwah 💋🌈