wb_split_bdi_pages(9)

wb_split_bdi_pages(9) is serving Kernel API Manual realness today, and honestly? iconic. 💅

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NAME 💖

wb_split_bdi_pages — split nr_pages to write according to bandwidth. periodt.

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SYNOPSIS ✨

long wb_split_bdi_pages (struct bdi_writeback *wb , long nr_pages );

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ARGUMENTS 🎀

• wb — the target bdi_writeback to split nr_pages to. she's the main character here 🫶
• nr_pages — number of pages to write for the whole bdi. yes bestie, the whole thing 😭

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DESCRIPTION 🦋

okay so here's the vibe: this function splits wb's portion of nr_pages according to wb's write bandwidth in relation to the total write bandwidth of all wb's with dirty inodes on wb->bdi. 🔥

it's giving proportional-split energy, and the math is literally doing the thing. no cap. 💜

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SEE ALSO 🌈

the kernel file is ./fs/fs-writeback.c, and these are the related girties — go read them, iykyk 👑

• inode_io_list_move_locked(9)
• wb_wait_for_completion(9)
• inode_cgwb_move_to_attached(9)
• locked_inode_to_wb_and_lock_list(9)
• inode_to_wb_and_lock_list(9)
• inode_switch_wbs(9)
• cleanup_offline_cgwb(9)
• wbc_attach_and_unlock_inode(9)
• wbc_attach_fdatawrite_inode(9)
• wbc_detach_inode(9)
• wbc_account_cgroup_owner(9)
• bdi_split_work_to_wbs(9)
• cgroup_writeback_by_id(9)
• cgroup_writeback_umount(9)
• wb_start_background_writeback(9)
• filemap_dontcache_kick_writeback(9)
• __mark_inode_dirty(9)
• writeback_inodes_sb_nr(9)
• writeback_inodes_sb(9)
• try_to_writeback_inodes_sb(9)
• sync_inodes_sb(9)
• write_inode_now(9)
• sync_inode_metadata(9)

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and that's the page, bestie 🫶 this lil beauty is signed off from the ./fs source/version corner, dated October 2026. slay ✨