calc_tx_descs_ofld(9)

✨ calc_tx_descs_ofld — Kernel API Manual bestie era ✨

okay so this is calc_tx_descs_ofld(9), and it’s giving “small but essential little kernel helper” energy. It lives in the Kernel API Manual, and it’s here to tell you how many Tx descriptors an offload packet needs. iconic. 💅

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🌸 NAME 🌸

calc_tx_descs_ofld — calculate # of Tx descriptors for an offload packet 💖

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🦋 SYNOPSIS 🦋

unsigned int calc_tx_descs_ofld (const struct sk_buff *skb );

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🎀 ARGUMENTS 🎀

• skb — the packet 💌

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💅 DESCRIPTION 💅

This function returns the number of Tx descriptors needed for the given offload packet. No cap: these packets are already fully constructed, so this is the descriptor-counting moment, not a “build the packet from scratch” situation. ✨

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🌈 SEE ALSO 🌈

The kernel file ./drivers/net/ethernet/chelsio/cxgb3/sge.c is the main-character file here, and these besties are all part of the same see-also friend group:

• refill_rspq(9)
• need_skb_unmap(9)
• unmap_skb(9)
• free_tx_desc(9)
• reclaim_completed_tx(9)
• should_restart_tx(9)
• free_rx_bufs(9)
• add_one_rx_buf(9)
• refill_fl(9)
• recycle_rx_buf(9)
• alloc_ring(9)
• t3_reset_qset(9)
• t3_free_qset(9)
• init_qset_cntxt(9)
• sgl_len(9)
• flits_to_desc(9)
• get_packet(9)
• get_packet_pg(9)
• get_imm_packet(9)
• calc_tx_descs(9)
• write_sgl(9)
• check_ring_tx_db(9)
• write_wr_hdr_sgl(9)
• write_tx_pkt_wr(9)
• t3_eth_xmit(9)
• write_imm(9)
• check_desc_avail(9)
• reclaim_completed_tx_imm(9)
• ctrl_xmit(9)
• restart_ctrlq(9)
• deferred_unmap_destructor(9)
• write_ofld_wr(9)
• ofld_xmit(9)
• restart_offloadq(9)
• queue_set(9)
• is_ctrl_pkt(9)
• t3_offload_tx(9)
• offload_enqueue(9)
• deliver_partial_bundle(9)
• ofld_poll(9)
• rx_offload(9)
• restart_tx(9)
• cxgb3_arp_process(9)
• rx_eth(9)
• lro_add_page(9)
• handle_rsp_cntrl_info(9)
• check_ring_db(9)
• is_new_response(9)
• process_responses(9)
• napi_rx_handler(9)
• process_pure_responses(9)
• handle_responses(9)
• t3_intr_handler(9)
• t3_sge_err_intr_handler(9)
• sge_timer_tx(9)
• sge_timer_rx(9)
• t3_update_qset_coalesce(9)
• t3_sge_alloc_qset(9)
• t3_start_sge_timers(9)
• t3_stop_sge_timers(9)
• t3_free_sge_resources(9)
• t3_sge_start(9)
• t3_sge_stop_dma(9)
• t3_sge_stop(9)
• t3_sge_init(9)
• t3_sge_prep(9)

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okay that’s the tea 💖 — source/version ./drivers/net/ethernet/chelsio..., dated October 2026. byeee bestie 🫶✨