pcpu_is_populated(9)

💅 pcpu_is_populated — NAME

okay so bestie, welcome to the Kernel API Manual (yes, the whole entire vibe ✨) and today we're looking at pcpu_is_populated — which literally just determines if the region is populated. that's it. that's the function. no cap. 🎀

🦋 SYNOPSIS

bool pcpu_is_populated (struct pcpu_chunk *chunk , int bit_off , int bits , int *next_off );

🌸 ARGUMENTS

• chunk — the chunk of interest, aka the main character of this whole operation 💖
• bit_off — the chunk offset, like where you're starting your little search bestie
• bits — size of the area, so how much we're looking at
• next_off — the return value for the next offset to start searching, iykyk 🌈

⭐ DESCRIPTION

so for atomic allocations, this checks if the backing pages are populated. periodt. that's the whole description, no need to overthink it bestie 💅

👑 RETURN

it gives you a bool — if the backing pages are populated. also lowkey:

next_index is to skip over unpopulated blocks in pcpu_find_block_fit.

(and yes the page really does say next_index there even though the argument is named next_off, we don't question the kernel gods, we just vibe 🙈)

✨ SEE ALSO

okay this list is iconic and long, buckle up besties, all from the kernel file ./mm/percpu.c:

• pcpu_addr_in_chunk(9)
• pcpu_check_block_hint(9)
• pcpu_next_md_free_region(9)
• pcpu_next_fit_region(9)
• pcpu_mem_zalloc(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_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)

and that's the whole page bestie! this gem lives in ./mm and the date stamped on it is October 2026 — so yeah, it's giving future vibes but we stan a timeless kernel API forever and always 💜🫶💖