port_r_cnt(9)

💅 port_r_cnt(9) — the "read your MIB counters before they overflow, bestie" page 🎀

okay so real quick — this is port_r_cnt, and it lives in the Kernel API Manual. That's the whole vibe. Now let's get into it ✨

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🌸 NAME 🌸

port_r_cnt — read MIB counters periodically. that's it, that's the errand 🧚

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✨ SYNOPSIS ✨

int port_r_cnt (struct ksz_hw *hw , int port );

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🦋 ARGUMENTS 🦋

• hw — the hardware instance. like, the actual chip you're talking to.
• port — the port index. which port we're clocking in for 🫶

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💖 DESCRIPTION 💖

so this routine is literally the "go read the port's counters" little guy, and you call it periodically — on a schedule, over and over — because if you don't, the counters overflow and then everything's cooked 😭 it's giving "drink water every hour" but for hardware statistics.

lowkey important: the hardware has to be acquired first before you call this routine. no cap. get the lock, then call. don't just roll up unannounced 💀

it returns non-zero when not all counters have been read. periodt.

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👑 SEE ALSO 👑

everything is connected, iykyk 💫 here's the whole friend group — starting with the kernel file itself:

Kernel file ./drivers/net/ethernet/micrel/ksz884x.c — and then, in order:

struct ksz_hw_desc(9), struct ksz_sw_desc(9), struct ksz_dma_buf(9), struct ksz_desc(9), struct ksz_desc_info(9), struct ksz_mac_table(9), struct ksz_vlan_table(9), struct ksz_port_mib(9), struct ksz_port_cfg(9), struct ksz_switch(9), struct ksz_port_info(9), struct ksz_hw(9), struct ksz_port(9), struct ksz_timer_info(9), struct ksz_shared_mem(9), struct ksz_counter_info(9), struct dev_info(9), struct dev_priv(9), hw_turn_on_intr(9), hw_block_intr(9), sw_r_table(9), sw_w_table_64(9), sw_w_sta_mac_table(9), sw_r_vlan_table(9), port_r_mib_cnt(9), port_r_mib_pkt(9), port_init_cnt(9), port_cfg(9), port_r8(9), port_r16(9), port_w16(9), sw_chk(9), sw_cfg(9), sw_cfg_broad_storm(9), sw_get_broad_storm(9), sw_dis_broad_storm(9), sw_ena_broad_storm(9), sw_init_broad_storm(9), hw_cfg_broad_storm(9), sw_dis_prio_rate(9), sw_init_prio_rate(9), sw_dis_diffserv(9), sw_dis_802_1p(9), sw_cfg_replace_null_vid(9), sw_cfg_replace_vid(9), sw_cfg_port_based(9), sw_dis_multi_queue(9), sw_init_prio(9), port_get_def_vid(9), sw_init_vlan(9), sw_cfg_port_base_vlan(9), sw_set_addr(9), sw_set_global_ctrl(9), port_set_stp_state(9), sw_clr_sta_mac_table(9), sw_init_stp(9), sw_block_addr(9), hw_r_phy(9), hw_w_phy(9), eeprom_read(9), eeprom_write(9), port_get_link_speed(9), port_set_link_speed(9), port_force_link_speed(9), hw_chk_wol_pme_status(9), hw_clr_wol_pme_status(9), hw_cfg_wol_pme(9), hw_cfg_wol(9), hw_set_wol_frame(9), hw_add_wol_arp(9), hw_add_wol_bcast(9), hw_add_wol_mcast(9), hw_add_wol_ucast(9), hw_enable_wol(9), hw_init(9), hw_reset(9), hw_setup(9), hw_setup_intr(9), hw_set_desc_base(9), hw_start_rx(9), hw_stop_rx(9), hw_start_tx(9), hw_stop_tx(9), hw_disable(9), hw_enable(9), hw_alloc_pkt(9), hw_send_pkt(9), hw_set_addr(9), hw_read_addr(9), hw_clr_multicast(9), hw_set_grp_addr(9), hw_set_multicast(9), hw_set_promiscuous(9), sw_enable(9), sw_setup(9), ksz_start_timer(9), ksz_stop_timer(9), ksz_alloc_soft_desc(9), ksz_alloc_desc(9), free_dma_buf(9), ksz_init_rx_buffers(9), ksz_alloc_mem(9), ksz_free_desc(9), ksz_free_buffers(9), ksz_free_mem(9), send_packet(9), transmit_cleanup(9), tx_done(9), netdev_tx(9), netdev_tx_timeout(9), netdev_intr(9), netdev_close(9), netdev_open(9), netdev_query_statistics(9), netdev_set_mac_address(9), netdev_set_rx_mode(9), netdev_ioctl(9), mdio_read(9), mdio_write(9), netdev_get_link_ksettings(9), netdev_set_link_ksettings(9), netdev_nway_reset(9), netdev_get_link(9), netdev_get_drvinfo(9), netdev_get_regs_len(9), netdev_get_regs(9), netdev_get_wol(9), netdev_set_wol(9), netdev_get_msglevel(9), netdev_set_msglevel(9), netdev_get_eeprom_len(9), netdev_get_eeprom(9), netdev_set_eeprom(9), netdev_get_pauseparam(9), netdev_set_pauseparam(9), netdev_get_ringparam(9), netdev_get_strings(9), netdev_get_sset_count(9), netdev_get_ethtool_stats(9), netdev_set_features(9), dev_monitor(9), netdev_init(9).

like I said. the whole friend group 🌈

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that's the page!! 🫶 cutest sign-off time: this one comes to you from ./drivers/net/ethernet/micrel, dated October 2026, and it's port_r_cnt(9) — go read those counters before they overflow, bestie, I'm begging 💜🎀