pcpu_mem_zalloc(9)

✨ pcpu_mem_zalloc(9) ✨

okay bestie, welcome to the Kernel API Manual 💅 — yes it's a section 9 page, yes it's about memory, no you can't skip it, this one's actually short and slay.

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💖 NAME 💖

pcpu_mem_zalloc — allocate memory 🎀

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🦋 SYNOPSIS 🦋

void * pcpu_mem_zalloc (size_t size , gfp_t gfp );

like, that's the whole function signature, no cap. takes two things, gives you back a pointer 🌸

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🌈 ARGUMENTS 🌈

• size — how many bytes you want, bestie. that's it. that's the number. 📏
• gfp — the allocation flags. the vibe parameters, if you will. ✨

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👑 DESCRIPTION 👑

so here's the tea 🍓 — you call this and it allocates size bytes for you. iconic.

but here's the lil plot twist: it picks how based on your size 👀

• if size is smaller than PAGE_SIZE → it uses kzalloc
• otherwise → it uses the equivalent of vzalloc

and why, you ask? because this is to facilitate passing through whitelisted flags 💀 like that's the whole reason. it's giving "we thought about it" energy.

the good news tho: the returned memory is always zeroed. every single time. no surprises. we love a consistent queen 👑✨

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🫶 RETURN 🫶

• success → a pointer to the allocated area 🎉
• failure → NULL 😭 (check it, bestie, please check it)

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⭐ SEE ALSO ⭐

Kernel file ./mm/percpu.c — and the whole percpu friend group, fr fr, they all show up together:

• pcpu_addr_in_chunk(9)
• pcpu_check_block_hint(9)
• pcpu_next_md_free_region(9)
• pcpu_next_fit_region(9)
• pcpu_mem_free(9)
• pcpu_chunk_relocate(9)
• pcpu_block_update(9)
• pcpu_chunk_refresh_hint(9)
• pcpu_block_refresh_hint(9)
• pcpu_block_update_hint_alloc(9)
• pcpu_block_update_hint_free(9)
• pcpu_is_populated(9)
• pcpu_find_block_fit(9)
• pcpu_alloc_area(9)
• pcpu_free_area(9)
• pcpu_alloc_first_chunk(9)
• pcpu_chunk_populated(9)
• pcpu_chunk_depopulated(9)
• pcpu_chunk_addr_search(9)
• pcpu_alloc(9)
• pcpu_balance_free(9)
• pcpu_balance_populated(9)
• pcpu_reclaim_populated(9)
• pcpu_balance_workfn(9)
• free_percpu(9)
• is_kernel_percpu_address(9)
• per_cpu_ptr_to_phys(9)
• pcpu_alloc_alloc_info(9)
• pcpu_free_alloc_info(9)
• pcpu_dump_alloc_info(9)
• pcpu_setup_first_chunk(9)
• pcpu_build_alloc_info(9)
• pcpu_embed_first_chunk(9)
• pcpu_page_first_chunk(9)

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and that's the page, bestie 💜 this lil baddie lives in ./mm, dated October 2026, and it goes by pcpu_mem_zalloc(9) — go forth and allocate responsibly, mwah 🧚💖