fm10k_fifo_used(9)

💅 fm10k_fifo_used(9) — the kernel API glow-up

okay so bestie, welcome to fm10k_fifo_used(9) 🎀 this is one of those tiny little helper pages from the kernel API manual, and honestly? she's short but she's important. let's get into it ✨

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🌸 NAME 🌸

fm10k_fifo_used — retrieve used space in FIFO. that's it. that's the whole job. and she does it flawlessly, no cap 💅

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⭐ SYNOPSIS ⭐

u16 fm10k_fifo_used (struct fm10k_mbx_fifo *fifo );

like, look at her. clean. iconic. returns a u16, takes exactly one thing, minds her own business 🫶

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🦋 ARGUMENTS 🦋

• fifo — pointer to FIFO 💖 yes bestie, that is literally a pointer to the FIFO. that's the whole argument. she's low maintenance.

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💀 DESCRIPTION 💀

so what does she actually do? this function returns the number of DWORDs used in the FIFO. that's the vibe. that's the tea. DWORDs used — not unused, not empty, not the head offset, not the tail offset. used. periodt 🔥

if you were looking for how much room is left, go find fm10k_fifo_unused(9) instead, because she is not that girl 🙈

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👑 SEE ALSO 👑

the squad 🫶 — start with the source, because reading code is self care:

• Kernel file ./drivers/net/ethernet/intel/fm10k/fm10k_mbx.c

and now, the full friend group, in order, don't skip anyone, we don't do that here 💜

fm10k_fifo_init(9), fm10k_fifo_unused(9), fm10k_fifo_empty(9), fm10k_fifo_head_offset(9), fm10k_fifo_tail_offset(9), fm10k_fifo_head_len(9), fm10k_fifo_head_drop(9), fm10k_fifo_drop_all(9), fm10k_mbx_index_len(9), fm10k_mbx_tail_add(9), fm10k_mbx_tail_sub(9), fm10k_mbx_head_add(9), fm10k_mbx_head_sub(9), fm10k_mbx_pushed_tail_len(9), fm10k_fifo_write_copy(9), fm10k_fifo_enqueue(9), fm10k_mbx_validate_msg_size(9), fm10k_mbx_write_copy(9), fm10k_mbx_pull_head(9), fm10k_mbx_read_copy(9), fm10k_mbx_push_tail(9), fm10k_crc_16b(9), fm10k_fifo_crc(9), fm10k_mbx_update_local_crc(9), fm10k_mbx_verify_remote_crc(9), fm10k_mbx_rx_ready(9), fm10k_mbx_tx_ready(9), fm10k_mbx_tx_complete(9), fm10k_mbx_dequeue_rx(9), fm10k_mbx_enqueue_tx(9), fm10k_mbx_read(9), fm10k_mbx_write(9), fm10k_mbx_create_connect_hdr(9), fm10k_mbx_create_data_hdr(9), fm10k_mbx_create_disconnect_hdr(9), fm10k_mbx_create_fake_disconnect_hdr(9), fm10k_mbx_create_error_msg(9), fm10k_mbx_validate_msg_hdr(9), fm10k_mbx_create_reply(9), fm10k_mbx_reset_work(9), fm10k_mbx_update_max_size(9), fm10k_mbx_connect_reset(9), fm10k_mbx_process_connect(9), fm10k_mbx_process_data(9), fm10k_mbx_process_disconnect(9), fm10k_mbx_process_error(9), fm10k_mbx_process(9), fm10k_mbx_disconnect(9), fm10k_mbx_connect(9), fm10k_mbx_validate_handlers(9), fm10k_mbx_register_handlers(9), fm10k_pfvf_mbx_init(9), fm10k_sm_mbx_create_data_hdr(9), fm10k_sm_mbx_create_connect_hdr(9), fm10k_sm_mbx_connect_reset(9), fm10k_sm_mbx_connect(9), fm10k_sm_mbx_disconnect(9), fm10k_sm_mbx_validate_fifo_hdr(9), fm10k_sm_mbx_process_error(9), fm10k_sm_mbx_create_error_msg(9), fm10k_sm_mbx_receive(9), fm10k_sm_mbx_transmit(9), fm10k_sm_mbx_create_reply(9), fm10k_sm_mbx_process_reset(9), fm10k_sm_mbx_process_version_1(9), fm10k_sm_mbx_process(9), fm10k_sm_mbx_init(9)

like… the whole mbx cinematic universe, fr fr 🌈 read them all, your future self will thank you 💖

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and that's the page bestie ✨ mwah 💋

source: ./drivers/net/ethernet/intel/f... (that's the truncated path the footer shows, don't come for me) — dated October 2026, manual fm10k_fifo_used(9) 🎀 bye ily 🫶