STRUCT GUC_SUBMIT_PARALLEL_SCRATCH(9)

💅 struct guc_submit_parallel_scratch(9)

okay so bestie, welcome to the Kernel API Manual ✨ — this one's a struct page, and honestly? she's giving "shared memory but make it organized." let's get into it 🎀

🌸 NAME 🌸

struct guc_submit_parallel_scratch — literally just a scratch, shared, mapped buffer 🫶 that's her whole job. a communal lil whiteboard for the kernel to scribble on, no cap.

✨ SYNOPSIS ✨

struct guc_submit_parallel_scratch {
    struct guc_sched_wq_desc wq_desc;
    struct sync_semaphore go;
    struct sync_semaphore join[XE_HW_ENGINE_MAX_INSTANCE];
    u8 unused[WQ_OFFSET - sizeof(struct guc_sched_wq_desc) -
sizeof(struct sync_semaphore) * (XE_HW_ENGINE_MAX_INSTANCE + 1)];
    u32 wq[WQ_SIZE / sizeof(u32)];
};

look at her. the layout. the intentional padding. the unused field doing absolutely nothing but holding space like a true icon 💀👑

🦋 Members 🦋

• wq_desc — the Guc scheduler workqueue descriptor 💖 the bouncer at the door of the workqueue, basically.
• go — the Go Semaphore 🔥 (yes that's her name, yes she's iconic) — the lil green light that says "okay go bestie".
• join — the joined semaphore for the relevant hw engine instances 🌈 she's an array, one per hw engine instance, up to XE_HW_ENGINE_MAX_INSTANCE of them. group chat, but make it semaphores.
• unused — Unused/Reserved memory space 🙈 she is padding. she is filler. she is the "brb" of struct fields. respect her anyway ✨
• wq — Workqueue info ⭐ stored as u32s, WQ_SIZE / sizeof(u32) of them. the actual receipts, the actual data.

ngl, that unused array is doing math to figure out its own size — WQ_OFFSET minus the descriptor minus all those semaphores. don't touch it, don't resize it, just let her vibe. it's alignment business, iykyk 🧚

👑 SEE ALSO 👑

• Kernel file ./drivers/gpu/drm/xe/xe_guc_submit_types.h 📁 — go read the source, bestie, she's right there
• struct xe_guc_submit_exec_queue_snapshot(9) — the related page, definitely worth a peek 💜

okay that's the whole page, fr fr 💖 this lil beauty lives in ./drivers/gpu/drm/xe, dated October 2026 — so yeah, she's from the future, main character energy only 🌟 bye bestie, go read some headers 🎀💅