qbman_swp_fq_xoff(9)

🌸 NAME 🌸

qbman_swp_fq_xoff(9) — from the Kernel API Manual, bestie — is literally the one that sets FQ flow-control to XOFF. 💅✨

✨ SYNOPSIS ✨

int qbman_swp_fq_xoff (struct qbman_swp *s , u32 fqid );

🎀 ARGUMENTS 🎀

• s — the software portal object. Yes, that one. 🫶
• fqid — the index of frame queue.

💅 DESCRIPTION 💅

Okay so listen: this setting doesn't affect enqueues to the FQ, just dequeues. Not enqueues, periodt. XOFF FQs will remain in the tenatively-scheduled state, even when non-empty, meaning they won't be selected for scheduled dequeuing. 😭

And if a FQ is changed to XOFF after it had already become truly-scheduled to a channel, and a pull dequeue of that channel occurs that selects that FQ for dequeuing, then the resulting dq_entry will have no FD. (qbman_result_DQ_fd will return NULL.) 💀

It returns 0 for success, or a negative error code for failure. So 0 is the slay; negative is the nope. ✨

🦋 SEE ALSO 🦋

Kernel file ./drivers/soc/fsl/dpio/qbman-portal.h, plus qbman_swp_enqueue(9), qbman_swp_enqueue_multiple(9), qbman_swp_enqueue_multiple_desc(9), qbman_result_is_DQ(9), qbman_result_is_SCN(9), qbman_result_SCN_state(9), qbman_result_SCN_rid(9), qbman_result_SCN_ctx(9), qbman_swp_fq_schedule(9), qbman_swp_fq_force(9), qbman_swp_fq_xon(9), qbman_swp_CDAN_set_context(9), qbman_swp_CDAN_enable(9), qbman_swp_CDAN_disable(9), qbman_swp_CDAN_set_context_enable(9), qbman_swp_release(9), qbman_swp_pull(9), qbman_swp_dqrr_next(9).

okay that's the whole vibe, bestie 🫶 this page came from the source/version ./drivers/soc/fsl/dpio and the date October 2026, and yes it's still qbman_swp_fq_xoff(9) 💖🌈