reset_psn(9)

🌸 NAME 🌸

okay bestie, meet reset_psn(9) from the Kernel API Manual — it literally resets the QP state to send starting from PSN. That's the whole vibe: QP state gets reset, and sending starts from the PSN you hand it. ✨

🎀 SYNOPSIS 🎀

void reset_psn (struct rvt_qp *qp , u32 psn );

💅 ARGUMENTS 💅

• qp — the QP. That's the one in question, bestie. 🫶
• psn — the packet sequence number to restart at. So this is the PSN where things pick back up. 🔥

🦋 DESCRIPTION 🦋

So here's the tea: this gets called from hfi1_rc_rcv to process an incoming RC ACK for the given QP. Yep — incoming RC ACK, given QP, all through hfi1_rc_rcv. 💌

Heads up: it's called at interrupt level with the QP s_lock held. That's the exact situation, no cap. ⚠️

💖 SEE ALSO 💖

Kernel file ./drivers/infiniband/hw/hfi1/rc.c — and the whole crew is:

• make_rc_ack(9)
• hfi1_make_rc_req(9)
• update_num_rd_atomic(9)
• hfi1_rc_verbs_aborted(9)
• update_qp_retry_state(9)
• rc_rcv_resp(9)
• rc_rcv_error(9)
• hfi1_rc_rcv(9)

byeee 🫶 source/version: ./drivers/infiniband/hw/hfi1 · date: October 2026 · page: reset_psn(9) — mwah 💋✨