STRUCT I915_GEM_PROTO_ENGINE(9)

💅 NAME 💅

struct i915_gem_proto_engine — the prototype engine bestie, aka the blueprint era of an engine ✨

Oh and hey, you found yourself in the struct i915_...proto_engine(9) page of the Kernel API Manual — welcome, pull up a chair 🫶

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🌸 SYNOPSIS 🌸

struct i915_gem_proto_engine {
    enum i915_gem_engine_type type;
    struct intel_engine_cs *engine;
    unsigned int num_siblings;
    unsigned int width;
    struct intel_engine_cs **siblings;
    struct intel_sseu sseu;
 };

Look at her. Six fields, zero notes, all main character energy 👑

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🎀 Members 🎀

• type — literally just the type of this engine, like a little name tag at a party 🏷️
• engine — the actual engine field, but only for the physical ones (physical girlies only, iykyk)
• num_siblings — how many balanced or parallel siblings we're talking about 👯
• width — the width of each sibling, yes every single one 📏
• siblings — the balanced siblings, or num_siblings * width when you're in parallel mode (math era fr fr)
• sseu — the client-set SSEU parameters 💫

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✨ Description ✨

Okay so this struct is out here describing an engine that a context may contain. And engines come in four types, no cap:

• I915_GEM_ENGINE_TYPE_INVALID — invalid engines can absolutely be created, but plot twist: they show up as a NULL in i915_gem_engines::engines[i], and the moment a user tries to actually use one, you get -EINVAL thrown at you 💀 They're also super useful during proto-context construction, because the client may create invalid engines and then set them up later as virtual engines. Glow-up arc 🦋
• I915_GEM_ENGINE_TYPE_PHYSICAL — a single physical engine, described by i915_gem_proto_engine::engine 🌟
• I915_GEM_ENGINE_TYPE_BALANCED — a load-balanced engine set, described by i915_gem_proto_engine::num_siblings and i915_gem_proto_engine::siblings ⚖️
• I915_GEM_ENGINE_TYPE_PARALLEL — a parallel submission engine set, described by i915_gem_proto_engine::width, i915_gem_proto_engine::num_siblings, and i915_gem_proto_engine::siblings 🏃‍♀️🏃‍♀️

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🌈 SEE ALSO 🌈

Go read these next, bestie, they're all in the kernel file ./drivers/gpu/drm/i915/gem/i915_gem_context_types.h:

• struct i915_gem_engines(9)
• struct i915_gem_engines_iter(9)
• enum i915_gem_engine_type(9)
• struct i915_gem_proto_context(9)
• struct i915_gem_context(9)

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Sending you off with the receipts 🧾 — this one lives in ./drivers/gpu/drm/i915/gem, dated October 2026, and she's officially struct i915_...proto_engine(9). That's the whole vibe check, mwah 💜💅