radeon_ib_schedule(9)

💖 radeon_ib_schedule(9) 💖

okay bestie, welcome to the Kernel API Manual — this one's all about yeeting an IB onto the ring, and honestly it's giving main-character energy. let's get into it 🫶

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✨ NAME ✨

radeon_ib_schedule — schedule an IB (Indirect Buffer) on the ring. periodt. 💅

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🌈 SYNOPSIS 🌈

int radeon_ib_schedule (struct radeon_device *rdev , struct radeon_ib
*ib , struct radeon_ib *const_ib , bool hdp_flush );

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🎀 ARGUMENTS 🎀

• rdev — a radeon_device pointer, aka the whole vibe of the device you're working with 🖥️
• ib — the IB object to schedule, the actual star of the show ⭐
• const_ib — the Const IB to schedule — SI only bestie, don't forget 😭
• hdp_flush — whether or not to perform an HDP cache flush — a simple lil yes/no vibe check 💅

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🦋 DESCRIPTION 🦋

So what does this actually do? It schedules an IB on the associated ring — and yes, that's all asics, no cap. It returns 0 on success and an error on failure. iconic behavior honestly. ✨

Now here's where it gets spicy 🔥 — on SI, there are two parallel engines fed from the primary ring:

• the CE (Constant Engine) 👑
• and the DE (Drawing Engine) 🎨

Since resource descriptors have moved to memory, the CE lets you prime the caches while the DE is updating register state — so that the resource descriptors will already be in cache when the draw is processed. the way that works is genuinely so smart, iykyk 🧠💖

To accomplish this, the userspace driver submits two IBs — one for the CE and one for the DE. If there is a CE IB (called a CONST_IB), it will be put on the ring prior to the DE IB. and prior to SI? there was just a DE IB. simpler times fr fr 🕰️

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🌸 SEE ALSO 🌸

• Kernel file ./drivers/gpu/drm/radeon/radeon_ib.c
• radeon_ib_get(9)
• radeon_ib_free(9)
• radeon_ib_pool_init(9)
• radeon_ib_pool_fini(9)
• radeon_ib_ring_tests(9)

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and that's the whole page bestie 🎀 this lil masterpiece comes from ./drivers/gpu/drm/radeon, dated October 2026, and it's literally called radeon_ib_schedule(9) — slay, go schedule some IBs responsibly 💜✨