enricobuehler
d7e01ad92e
Chasing the 8ms submit at 1440p on the 780M: the sampled PUNKTFUNK_PERF split (push/pull/send) shows desc+buffersrc at ~5us, hwmap-import+VPP CSC at ~0.2-0.5ms, and avcodec_send_frame owning the rest — so neither a VA-surface import cache nor CSC overlap would help. Two facts landed: (1) async_depth>=2 in libavcodec's vaapi_encode is a structural +1-frame latency (frame N's packet only materializes when N+1 queues; measured 18ms vs 8.3ms p50 at depth 1) — depth 1 stays the default, PUNKTFUNK_VAAPI_ASYNC_DEPTH exists for pixel rates beyond the ASIC's serial budget, and poll() now does a bounded in-flight wait so a deeper depth still ships the AU as soon as the ASIC finishes. (2) The residual send_frame block tracks GPU CLOCKS, not the ASIC: ~8ms/frame at a 60fps duty cycle vs ~4.4ms at 120fps pacing vs 3.5ms back-to-back (270fps CLI benchmark, even at -async_depth 1) — the clock-sag fix lands in gpuclocks. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
1146 lines
54 KiB
Rust
1146 lines
54 KiB
Rust
//! VAAPI encoder via `ffmpeg-next` — AMD (Mesa `radeonsi`) and Intel (`iHD`/`i965`) over one
|
||
//! libavcodec backend (`h264_vaapi`/`hevc_vaapi`/`av1_vaapi`). The kernel driver differs per
|
||
//! vendor; the libva userspace API is identical, so a single encoder covers both. This is the
|
||
//! sibling of [`super::linux`] (NVENC/CUDA) behind the shared [`Encoder`] trait — selected in
|
||
//! [`super::open_video`] (NVIDIA → NVENC, AMD/Intel → here).
|
||
//!
|
||
//! Two input paths, chosen lazily from the FIRST frame's payload (so `open_video`'s signature
|
||
//! is unchanged and the encoder self-configures for whatever the capturer produces):
|
||
//! * **CPU upload** ([`CpuInner`]): the portal hands packed RGB/BGR CPU frames; we swscale to
|
||
//! BT.709-limited NV12 and `av_hwframe_transfer_data` it into a pooled VA surface. Works on any
|
||
//! VAAPI GPU with no capture changes (the capturer falls back to CPU frames on non-NVIDIA).
|
||
//! * **Zero-copy dmabuf** ([`DmabufInner`], `PUNKTFUNK_ZEROCOPY=1`): the capturer hands a packed-RGB
|
||
//! dmabuf. We wrap it as an `AV_PIX_FMT_DRM_PRIME` frame and push it through a tiny filter graph
|
||
//! `buffer(drm_prime) → hwmap=derive_device=vaapi → scale_vaapi=format=nv12 → buffersink`, so
|
||
//! the import AND the RGB→NV12 colour conversion run on the GPU's video engine — no host CSC, no
|
||
//! upload. The encoder takes the NV12 surfaces straight from the filter sink.
|
||
//!
|
||
//! Raw FFI: `ffmpeg-next` has no hwcontext/filter wrappers for what we need, so the
|
||
//! hwdevice/hwframes/buffersrc/buffersink calls go through `ffmpeg::ffi` (= `ffmpeg_sys_next`),
|
||
//! as the CUDA encode path and the clients' decode paths already do. The encoder is opened
|
||
//! *without* a global header, so VPS/SPS/PPS are in-band on every IDR.
|
||
// Every `unsafe` block in this file carries a `// SAFETY:` proof; enforce it (unsafe-proof program).
|
||
#![deny(clippy::undocumented_unsafe_blocks)]
|
||
|
||
use super::{Codec, EncodedFrame, Encoder};
|
||
use crate::capture::{CapturedFrame, DmabufFrame, FramePayload, PixelFormat};
|
||
use anyhow::{anyhow, bail, Context, Result};
|
||
use ffmpeg::format::Pixel;
|
||
use ffmpeg::{codec, encoder, Dictionary, Packet, Rational};
|
||
use ffmpeg_next as ffmpeg;
|
||
use std::ffi::{CStr, CString};
|
||
use std::os::fd::AsRawFd;
|
||
use std::os::raw::c_int;
|
||
use std::ptr;
|
||
use std::sync::atomic::{AtomicU8, Ordering};
|
||
|
||
use ffmpeg::ffi; // = ffmpeg_sys_next
|
||
|
||
// libswscale scaler-flag + colour-space constants (not exported as Rust consts by the bindings;
|
||
// these are the stable `<libswscale/swscale.h>` #defines). No-rescale → POINT is cheapest.
|
||
const SWS_POINT: c_int = 0x10;
|
||
const SWS_CS_ITU709: c_int = 1;
|
||
|
||
/// `ffmpeg::format::Pixel` → raw `AVPixelFormat` (the documented ffmpeg-next conversion).
|
||
fn pixel_to_av(p: Pixel) -> ffi::AVPixelFormat {
|
||
ffi::AVPixelFormat::from(p)
|
||
}
|
||
|
||
/// `fourcc(a,b,c,d)` — DRM FourCC packing (`a | b<<8 | c<<16 | d<<24`).
|
||
const fn fourcc(a: u8, b: u8, c: u8, d: u8) -> u32 {
|
||
(a as u32) | ((b as u32) << 8) | ((c as u32) << 16) | ((d as u32) << 24)
|
||
}
|
||
|
||
/// The render node a VAAPI/DRM device should open, from [`crate::gpu::linux_render_node`]: a
|
||
/// matched web-console GPU preference pins it, else `PUNKTFUNK_RENDER_NODE`, else the single-GPU
|
||
/// default.
|
||
fn render_node() -> CString {
|
||
let p = crate::gpu::linux_render_node()
|
||
.to_string_lossy()
|
||
.into_owned();
|
||
CString::new(p).unwrap_or_else(|_| CString::new("/dev/dri/renderD128").unwrap())
|
||
}
|
||
|
||
/// The swscale *source* pixel format for a captured CPU layout (packed RGB/BGR only).
|
||
fn vaapi_sws_src(format: PixelFormat) -> Result<Pixel> {
|
||
Ok(match format {
|
||
PixelFormat::Bgrx => Pixel::BGRZ, // bgr0
|
||
PixelFormat::Rgbx => Pixel::RGBZ, // rgb0
|
||
PixelFormat::Bgra => Pixel::BGRA,
|
||
PixelFormat::Rgba => Pixel::RGBA,
|
||
PixelFormat::Rgb => Pixel::RGB24,
|
||
PixelFormat::Bgr => Pixel::BGR24,
|
||
PixelFormat::Nv12 | PixelFormat::P010 | PixelFormat::Rgb10a2 => {
|
||
bail!("VAAPI CPU-input path supports packed RGB/BGR only; got {format:?}")
|
||
}
|
||
})
|
||
}
|
||
|
||
/// Which VAAPI entrypoint mode opened successfully, cached per codec (index = [`lp_idx`]):
|
||
/// 0 = unknown, 1 = default (full-feature `EncSlice`), 2 = low-power (`EncSliceLP`/VDEnc).
|
||
/// Modern Intel (Gen12+/Arc) removed the full-feature encode entrypoints, so the default open
|
||
/// fails there and only `low_power=1` works; AMD (radeonsi) is the reverse. Caching the resolved
|
||
/// mode lets later sessions/probes skip the known-failing attempt (and its libav error spew).
|
||
static LP_MODE: [AtomicU8; 3] = [AtomicU8::new(0), AtomicU8::new(0), AtomicU8::new(0)];
|
||
|
||
fn lp_idx(codec: Codec) -> usize {
|
||
match codec {
|
||
Codec::H264 => 0,
|
||
Codec::H265 => 1,
|
||
Codec::Av1 => 2,
|
||
}
|
||
}
|
||
|
||
/// `PUNKTFUNK_VAAPI_LOW_POWER` pins the entrypoint mode (`1` = low-power only, `0` = full-feature
|
||
/// only); unset → try full-feature first, fall back to low-power.
|
||
fn low_power_override() -> Option<bool> {
|
||
match std::env::var("PUNKTFUNK_VAAPI_LOW_POWER").ok()?.trim() {
|
||
"1" | "true" | "yes" | "on" => Some(true),
|
||
"0" | "false" | "no" | "off" => Some(false),
|
||
_ => None,
|
||
}
|
||
}
|
||
|
||
/// Open the VAAPI encoder, resolving the entrypoint mode: try the full-feature entrypoint first
|
||
/// and, if the driver rejects it, retry with `low_power=1` — modern Intel (Gen12+/Arc) exposes
|
||
/// ONLY the low-power VDEnc entrypoint (ffmpeg's `vaapi_encode` defaults `low_power=0` and errors
|
||
/// "no usable encoding entrypoint" there; LP additionally needs the HuC firmware, loaded by
|
||
/// default on those kernels). AMD keeps its first-try full-feature open byte-for-byte unchanged.
|
||
/// The resolved mode is cached per codec; `PUNKTFUNK_VAAPI_LOW_POWER` pins it.
|
||
/// Safety contract is [`open_vaapi_encoder_mode`]'s (borrowed `device_ref`/`frames_ref`).
|
||
unsafe fn open_vaapi_encoder(
|
||
codec: Codec,
|
||
width: u32,
|
||
height: u32,
|
||
fps: u32,
|
||
bitrate_bps: u64,
|
||
device_ref: *mut ffi::AVBufferRef,
|
||
frames_ref: *mut ffi::AVBufferRef,
|
||
) -> Result<encoder::video::Encoder> {
|
||
let idx = lp_idx(codec);
|
||
let modes: &[bool] = match low_power_override() {
|
||
Some(true) => &[true],
|
||
Some(false) => &[false],
|
||
None => match LP_MODE[idx].load(Ordering::Relaxed) {
|
||
1 => &[false],
|
||
2 => &[true],
|
||
_ => &[false, true],
|
||
},
|
||
};
|
||
let mut first_err = None;
|
||
for &lp in modes {
|
||
match open_vaapi_encoder_mode(
|
||
codec,
|
||
width,
|
||
height,
|
||
fps,
|
||
bitrate_bps,
|
||
device_ref,
|
||
frames_ref,
|
||
lp,
|
||
) {
|
||
Ok(enc) => {
|
||
LP_MODE[idx].store(if lp { 2 } else { 1 }, Ordering::Relaxed);
|
||
if lp {
|
||
tracing::info!(
|
||
encoder = codec.vaapi_name(),
|
||
"VAAPI using the low-power (VDEnc) entrypoint"
|
||
);
|
||
}
|
||
return Ok(enc);
|
||
}
|
||
Err(e) => {
|
||
tracing::debug!(
|
||
encoder = codec.vaapi_name(),
|
||
low_power = lp,
|
||
"VAAPI encoder open failed: {e:#}"
|
||
);
|
||
first_err.get_or_insert(e);
|
||
}
|
||
}
|
||
}
|
||
// `modes` is never empty, so at least one attempt ran and recorded its error. The first
|
||
// (full-feature) error is the informative one — "no VA display" etc.
|
||
Err(first_err.unwrap())
|
||
}
|
||
|
||
/// Build the FFmpeg encoder context (shared by both inner paths): name, mode, low-latency RC,
|
||
/// infinite GOP, BT.709-limited VUI, `pix_fmt=VAAPI`, and the given hw device + frames contexts.
|
||
/// Returns the opened encoder. `device_ref`/`frames_ref` are borrowed (ref'd into the context).
|
||
#[allow(clippy::too_many_arguments)]
|
||
unsafe fn open_vaapi_encoder_mode(
|
||
codec: Codec,
|
||
width: u32,
|
||
height: u32,
|
||
fps: u32,
|
||
bitrate_bps: u64,
|
||
device_ref: *mut ffi::AVBufferRef,
|
||
frames_ref: *mut ffi::AVBufferRef,
|
||
low_power: bool,
|
||
) -> Result<encoder::video::Encoder> {
|
||
let name = codec.vaapi_name();
|
||
let av_codec = encoder::find_by_name(name).ok_or_else(|| {
|
||
anyhow!("{name} not built into libavcodec (no VAAPI encoder for {codec:?})")
|
||
})?;
|
||
let mut video = codec::context::Context::new_with_codec(av_codec)
|
||
.encoder()
|
||
.video()
|
||
.context("alloc video encoder")?;
|
||
video.set_width(width);
|
||
video.set_height(height);
|
||
video.set_format(Pixel::NV12); // sw view; pix_fmt overridden to VAAPI below
|
||
video.set_time_base(Rational(1, fps as i32));
|
||
video.set_frame_rate(Some(Rational(fps as i32, 1)));
|
||
video.set_bit_rate(bitrate_bps as usize);
|
||
video.set_max_bit_rate(bitrate_bps as usize); // == target → vaapi_encode picks CBR when supported
|
||
let vbv_frames = std::env::var("PUNKTFUNK_VBV_FRAMES")
|
||
.ok()
|
||
.and_then(|s| s.parse::<f32>().ok())
|
||
.filter(|v| v.is_finite() && *v > 0.0)
|
||
.unwrap_or(1.0);
|
||
let vbv_bits =
|
||
((bitrate_bps as f64 / fps.max(1) as f64) * vbv_frames as f64).clamp(1.0, i32::MAX as f64);
|
||
video.set_max_b_frames(0);
|
||
let raw = video.as_mut_ptr();
|
||
(*raw).rc_buffer_size = vbv_bits as i32;
|
||
(*raw).gop_size = i32::MAX; // no periodic IDR (forced-IDR via pict_type=I on RFI)
|
||
// We hand the encoder BT.709 *limited* NV12 (swscale CSC, or scale_vaapi which preserves the
|
||
// input range we tag), so signal that VUI — else the client decoder washes the picture out.
|
||
(*raw).colorspace = ffi::AVColorSpace::AVCOL_SPC_BT709;
|
||
(*raw).color_range = ffi::AVColorRange::AVCOL_RANGE_MPEG;
|
||
(*raw).color_primaries = ffi::AVColorPrimaries::AVCOL_PRI_BT709;
|
||
(*raw).color_trc = ffi::AVColorTransferCharacteristic::AVCOL_TRC_BT709;
|
||
(*raw).pix_fmt = ffi::AVPixelFormat::AV_PIX_FMT_VAAPI;
|
||
(*raw).hw_device_ctx = ffi::av_buffer_ref(device_ref);
|
||
(*raw).hw_frames_ctx = ffi::av_buffer_ref(frames_ref);
|
||
|
||
let mut opts = Dictionary::new();
|
||
// async_depth=1: `send_frame` blocks until THIS frame's ASIC encode completes — the lowest
|
||
// latency structure libavcodec's vaapi_encode offers. Measured on the 780M at 1440p60: depth 1
|
||
// = 8.3 ms end-to-end p50 vs depth 2 = 18 ms, because with depth ≥ 2 frame N's packet only
|
||
// materializes once frame N+1 is queued (a structural +1-frame delay no poll can beat). The
|
||
// knob exists for pixel rates beyond the ASIC's serial budget (e.g. 1440p120+ on an iGPU),
|
||
// where depth 2 restores throughput at that one-frame cost. NOTE: the per-frame block tracks
|
||
// GPU CLOCKS — a paced 60 fps trickle lets the VCN downclock (~8 ms/frame vs ~4.4 ms hot);
|
||
// see `gpuclocks` for the session clock pin that removes the ramp tax.
|
||
let depth = std::env::var("PUNKTFUNK_VAAPI_ASYNC_DEPTH")
|
||
.ok()
|
||
.and_then(|s| s.parse::<u32>().ok())
|
||
.filter(|d| (1..=8).contains(d))
|
||
.unwrap_or(1);
|
||
opts.set("async_depth", &depth.to_string());
|
||
if low_power {
|
||
opts.set("low_power", "1"); // VDEnc — the only encode entrypoint on modern Intel
|
||
}
|
||
video.open_with(opts).with_context(|| {
|
||
format!("open {name} ({width}x{height}@{fps}, {bitrate_bps} bps, low_power={low_power})")
|
||
})
|
||
}
|
||
|
||
/// Probe whether THIS GPU can VAAPI-encode `codec`, by opening a tiny encoder: the driver rejects
|
||
/// codecs its video engine can't do (e.g. AV1 on pre-RDNA3 AMD / pre-Arc Intel). Used to build the
|
||
/// GameStream codec advertisement so a client never negotiates a codec the GPU can't encode. The
|
||
/// device + encoder are torn down immediately (RAII).
|
||
pub fn probe_can_encode(codec: Codec) -> bool {
|
||
if ffmpeg::init().is_err() {
|
||
return false;
|
||
}
|
||
// SAFETY: `ffmpeg::init()` returned Ok above, so libav is initialized. `av_log_get_level`/
|
||
// `av_log_set_level` only read/write libav's global integer log level (no pointer args) and are
|
||
// always sound to call post-init. `VaapiHw::new` (an `unsafe fn`) builds a VAAPI device + NV12
|
||
// frames pool from the literal NV12/640x480/pool=2 args and hands back a RAII handle that unrefs
|
||
// both `AVBufferRef`s on drop. `open_vaapi_encoder` (an `unsafe fn`) borrows `hw.device_ref`/
|
||
// `hw.frames_ref` — the two non-null refs `VaapiHw::new` just created — and `av_buffer_ref`s them
|
||
// into the encoder; `hw` is a live local for the whole match arm, so the borrows outlive the
|
||
// synchronous call, and both `hw` and the probe encoder are dropped (RAII) when the arm ends.
|
||
unsafe {
|
||
// A missing VA device (non-VAAPI host, GPU-less CI) is an expected probe outcome — quiet
|
||
// ffmpeg's "No VA display found" error for the probe, then restore the level.
|
||
let prev = ffi::av_log_get_level();
|
||
ffi::av_log_set_level(ffi::AV_LOG_FATAL);
|
||
let ok = match VaapiHw::new(ffi::AVPixelFormat::AV_PIX_FMT_NV12, 640, 480, 2) {
|
||
Ok(hw) => {
|
||
open_vaapi_encoder(codec, 640, 480, 30, 2_000_000, hw.device_ref, hw.frames_ref)
|
||
.is_ok()
|
||
}
|
||
Err(_) => false,
|
||
};
|
||
ffi::av_log_set_level(prev);
|
||
ok
|
||
}
|
||
}
|
||
|
||
/// Whether the active VAAPI GPU can encode HEVC **4:4:4** (Range Extensions). **Deferred in v1 —
|
||
/// always `false`.** VAAPI HEVC 4:4:4 encode is narrow and vendor-specific (the lab's AMD Phoenix1 /
|
||
/// RDNA3 exposes only `VAProfileHEVCMain`/`Main10` `EncSlice`, no `Main444`), and there is no
|
||
/// validated hardware to build + verify the 4:4:4 surface/profile path against. Returning `false`
|
||
/// keeps the negotiation honest: a VAAPI host resolves every session to 4:2:0 before the Welcome, so
|
||
/// the client never builds a 4:4:4 decoder it would only get 4:2:0 frames for. (Follow-up: implement
|
||
/// and validate on an Intel Arc / RDNA4-class box that advertises a HEVC 4:4:4 encode entrypoint.)
|
||
pub fn probe_can_encode_444(_codec: Codec) -> bool {
|
||
tracing::info!("VAAPI HEVC 4:4:4 encode is not implemented yet — declining (encoding 4:2:0)");
|
||
false
|
||
}
|
||
|
||
/// Drain the encoder for one packet (shared poll logic).
|
||
fn poll_encoder(enc: &mut encoder::video::Encoder, fps: u32) -> Result<Option<EncodedFrame>> {
|
||
let mut pkt = Packet::empty();
|
||
match enc.receive_packet(&mut pkt) {
|
||
Ok(()) => {
|
||
let data = pkt.data().map(|d| d.to_vec()).unwrap_or_default();
|
||
let pts = pkt.pts().unwrap_or(0).max(0) as u64;
|
||
Ok(Some(EncodedFrame {
|
||
data,
|
||
pts_ns: pts * 1_000_000_000 / fps as u64,
|
||
keyframe: pkt.is_key(),
|
||
}))
|
||
}
|
||
Err(ffmpeg::Error::Other { errno })
|
||
if errno == ffmpeg::util::error::EAGAIN
|
||
|| errno == ffmpeg::util::error::EWOULDBLOCK =>
|
||
{
|
||
Ok(None)
|
||
}
|
||
Err(ffmpeg::Error::Eof) => Ok(None),
|
||
Err(e) => Err(e).context("receive_packet"),
|
||
}
|
||
}
|
||
|
||
// ---------------------------------------------------------------------------------------------
|
||
// CPU upload path (Phase 1): swscale RGB→NV12 → upload into a pooled VA surface → encode.
|
||
// ---------------------------------------------------------------------------------------------
|
||
|
||
/// VAAPI device + NV12 frames pool (the encoder's input surfaces for the CPU path).
|
||
struct VaapiHw {
|
||
device_ref: *mut ffi::AVBufferRef,
|
||
frames_ref: *mut ffi::AVBufferRef,
|
||
}
|
||
|
||
impl VaapiHw {
|
||
unsafe fn new(sw_format: ffi::AVPixelFormat, w: u32, h: u32, pool: c_int) -> Result<Self> {
|
||
let mut device_ref: *mut ffi::AVBufferRef = ptr::null_mut();
|
||
let node = render_node();
|
||
let r = ffi::av_hwdevice_ctx_create(
|
||
&mut device_ref,
|
||
ffi::AVHWDeviceType::AV_HWDEVICE_TYPE_VAAPI,
|
||
node.as_ptr(),
|
||
ptr::null_mut(),
|
||
0,
|
||
);
|
||
if r < 0 {
|
||
bail!("no VAAPI device ({:?}): {}", node, ffmpeg::Error::from(r));
|
||
}
|
||
let mut frames_ref = ffi::av_hwframe_ctx_alloc(device_ref);
|
||
if frames_ref.is_null() {
|
||
ffi::av_buffer_unref(&mut device_ref);
|
||
bail!("av_hwframe_ctx_alloc(VAAPI) failed");
|
||
}
|
||
let fc = (*frames_ref).data as *mut ffi::AVHWFramesContext;
|
||
(*fc).format = ffi::AVPixelFormat::AV_PIX_FMT_VAAPI;
|
||
(*fc).sw_format = sw_format;
|
||
(*fc).width = w as c_int;
|
||
(*fc).height = h as c_int;
|
||
(*fc).initial_pool_size = pool;
|
||
let r = ffi::av_hwframe_ctx_init(frames_ref);
|
||
if r < 0 {
|
||
ffi::av_buffer_unref(&mut frames_ref);
|
||
ffi::av_buffer_unref(&mut device_ref);
|
||
bail!("av_hwframe_ctx_init(VAAPI) failed ({r})");
|
||
}
|
||
Ok(VaapiHw {
|
||
device_ref,
|
||
frames_ref,
|
||
})
|
||
}
|
||
}
|
||
|
||
impl Drop for VaapiHw {
|
||
fn drop(&mut self) {
|
||
// SAFETY: `frames_ref`/`device_ref` are the two non-null `AVBufferRef`s `VaapiHw::new`
|
||
// created (it bails before constructing `Self` if either alloc fails, so a live `VaapiHw`
|
||
// always holds both). `av_buffer_unref` drops one reference and nulls the pointer through the
|
||
// `&mut`. This `Drop` runs exactly once and `VaapiHw` owns these refs exclusively, so there
|
||
// is no double-free / use-after-free. Frames are unref'd before the device because the frames
|
||
// ctx internally holds a ref on the device (refcounted, so the order is sound either way).
|
||
unsafe {
|
||
ffi::av_buffer_unref(&mut self.frames_ref);
|
||
ffi::av_buffer_unref(&mut self.device_ref);
|
||
}
|
||
}
|
||
}
|
||
|
||
struct CpuInner {
|
||
enc: encoder::video::Encoder,
|
||
hw: VaapiHw,
|
||
sws: *mut ffi::SwsContext,
|
||
nv12: *mut ffi::AVFrame, // reusable software NV12 staging frame (swscale dst → upload src)
|
||
src_format: PixelFormat,
|
||
width: u32,
|
||
height: u32,
|
||
}
|
||
|
||
impl CpuInner {
|
||
fn open(
|
||
codec: Codec,
|
||
format: PixelFormat,
|
||
width: u32,
|
||
height: u32,
|
||
fps: u32,
|
||
bitrate_bps: u64,
|
||
) -> Result<Self> {
|
||
let src_pixel = vaapi_sws_src(format)?;
|
||
const POOL: c_int = 16;
|
||
// SAFETY: `VaapiHw::new` (an `unsafe fn`) requires libav initialized — guaranteed because the
|
||
// only path here is `VaapiEncoder::open` → `ensure_inner` → `CpuInner::open`, and `open` ran
|
||
// `ffmpeg::init()`. The args are valid: NV12 sw_format, the validated positive `width`/`height`,
|
||
// pool=16. It returns a RAII `VaapiHw` that unrefs its two `AVBufferRef`s on drop.
|
||
let hw = unsafe { VaapiHw::new(ffi::AVPixelFormat::AV_PIX_FMT_NV12, width, height, POOL)? };
|
||
// SAFETY: `open_vaapi_encoder` (an `unsafe fn`) borrows `hw.device_ref`/`hw.frames_ref` — both
|
||
// non-null (`VaapiHw::new` guarantees it) and from the `hw` just built above, which is a live
|
||
// local that outlives this synchronous call. The fn `av_buffer_ref`s them into the encoder, so
|
||
// the encoder holds its own references; `hw` is also moved into the returned `CpuInner` next to
|
||
// `enc`, keeping the device/frames alive for the encoder's whole lifetime.
|
||
let enc = unsafe {
|
||
open_vaapi_encoder(
|
||
codec,
|
||
width,
|
||
height,
|
||
fps,
|
||
bitrate_bps,
|
||
hw.device_ref,
|
||
hw.frames_ref,
|
||
)?
|
||
};
|
||
// swscale RGB→NV12, BT.709 limited (matches the VUI), no rescale.
|
||
let src_av = pixel_to_av(src_pixel);
|
||
// SAFETY: `sws_getContext` allocates a swscale context for the given src/dst dimensions and
|
||
// pixel formats. All four dims are the encoder's positive `width`/`height` cast to `c_int`;
|
||
// `src_av` is a valid `AVPixelFormat` (from `pixel_to_av` of the `vaapi_sws_src`-validated
|
||
// `src_pixel`), the dst is NV12. The three trailing pointers (srcFilter, dstFilter, param) are
|
||
// explicitly null = "use defaults", which the API documents as accepted. No Rust memory is
|
||
// borrowed — only by-value ints/enums — and the returned pointer is null-checked just below.
|
||
let sws = unsafe {
|
||
ffi::sws_getContext(
|
||
width as c_int,
|
||
height as c_int,
|
||
src_av,
|
||
width as c_int,
|
||
height as c_int,
|
||
ffi::AVPixelFormat::AV_PIX_FMT_NV12,
|
||
SWS_POINT,
|
||
ptr::null_mut(),
|
||
ptr::null_mut(),
|
||
ptr::null(),
|
||
)
|
||
};
|
||
if sws.is_null() {
|
||
bail!("sws_getContext(RGB→NV12) failed");
|
||
}
|
||
// SAFETY: `sws` is the non-null `SwsContext` from `sws_getContext` above (the `is_null()`
|
||
// check immediately preceding returned false). `sws_getCoefficients(SWS_CS_ITU709)` returns a
|
||
// pointer into a libswscale static const coefficient table valid for the whole process, reused
|
||
// here for both the inverse (src) and forward (dst) matrices. `sws_setColorspaceDetails` only
|
||
// reads those tables and writes scalar CSC settings into `sws`; the table pointer outlives the
|
||
// synchronous call and no Rust memory is passed.
|
||
unsafe {
|
||
let cs709 = ffi::sws_getCoefficients(SWS_CS_ITU709);
|
||
ffi::sws_setColorspaceDetails(sws, cs709, 1, cs709, 0, 0, 1 << 16, 1 << 16);
|
||
}
|
||
// SAFETY: `av_frame_alloc` returns a fresh, uniquely-owned heap `AVFrame` (null-checked — on
|
||
// null we free the already-built `sws` and bail). We then write the plain `format`/`width`/
|
||
// `height` fields through the non-null, properly-aligned `f` (sole owner, not yet shared).
|
||
// `av_frame_get_buffer(f, 0)` allocates backing storage for those dims/format; on failure we
|
||
// free `f` and `sws` (unwinding the half-built state) and bail. On success `f` is a fully-owned
|
||
// NV12 frame stored in `CpuInner.nv12` and freed once in `CpuInner::drop`. `f` is a unique
|
||
// fresh pointer, so none of these writes alias anything.
|
||
let nv12 = unsafe {
|
||
let f = ffi::av_frame_alloc();
|
||
if f.is_null() {
|
||
ffi::sws_freeContext(sws);
|
||
bail!("av_frame_alloc(NV12) failed");
|
||
}
|
||
(*f).format = ffi::AVPixelFormat::AV_PIX_FMT_NV12 as c_int;
|
||
(*f).width = width as c_int;
|
||
(*f).height = height as c_int;
|
||
if ffi::av_frame_get_buffer(f, 0) < 0 {
|
||
let mut f = f;
|
||
ffi::av_frame_free(&mut f);
|
||
ffi::sws_freeContext(sws);
|
||
bail!("av_frame_get_buffer(NV12) failed");
|
||
}
|
||
f
|
||
};
|
||
tracing::info!(
|
||
encoder = codec.vaapi_name(),
|
||
"VAAPI encode active ({width}x{height}@{fps}, CPU→NV12 upload path)"
|
||
);
|
||
Ok(CpuInner {
|
||
enc,
|
||
hw,
|
||
sws,
|
||
nv12,
|
||
src_format: format,
|
||
width,
|
||
height,
|
||
})
|
||
}
|
||
|
||
fn submit(&mut self, bytes: &[u8], format: PixelFormat, pts: i64, idr: bool) -> Result<()> {
|
||
anyhow::ensure!(
|
||
format == self.src_format,
|
||
"captured format {format:?} != encoder source {:?}",
|
||
self.src_format
|
||
);
|
||
let w = self.width as usize;
|
||
let h = self.height as usize;
|
||
let src_row = w * self.src_format.bytes_per_pixel();
|
||
anyhow::ensure!(bytes.len() >= src_row * h, "captured buffer too small");
|
||
// SAFETY: The `ensure!`s above guarantee `format == self.src_format` and
|
||
// `bytes.len() >= src_row * h`. `sws_scale` reads `h` rows of `src_row` bytes from
|
||
// `src_data[0] = bytes.as_ptr()` (the other planes null/0 — packed RGB is single-plane), all
|
||
// in bounds; `bytes`, `src_data`, `src_stride` are live locals for this synchronous call.
|
||
// `self.sws` is the non-null context built in `open`; it writes into `self.nv12` (a non-null
|
||
// owned frame whose `data`/`linesize` in-struct arrays were sized by `av_frame_get_buffer`).
|
||
// `av_frame_alloc` (null-checked) yields a fresh `hwf`; `av_hwframe_get_buffer` pulls a pooled
|
||
// VAAPI surface from the live non-null `self.hw.frames_ref`; `av_hwframe_transfer_data` uploads
|
||
// the staged NV12 into it — both frames live, failures free `hwf` and bail. We then write
|
||
// `pts`/`pict_type` through the non-null `hwf` and `avcodec_send_frame` it into the live
|
||
// owned `self.enc` context (which takes its own ref), then free our `hwf` ref exactly once.
|
||
// The encoder runs only on this thread (see `unsafe impl Send`), so no aliasing/data race.
|
||
unsafe {
|
||
let src_data: [*const u8; 4] = [bytes.as_ptr(), ptr::null(), ptr::null(), ptr::null()];
|
||
let src_stride: [c_int; 4] = [src_row as c_int, 0, 0, 0];
|
||
if ffi::sws_scale(
|
||
self.sws,
|
||
src_data.as_ptr(),
|
||
src_stride.as_ptr(),
|
||
0,
|
||
h as c_int,
|
||
(*self.nv12).data.as_ptr(),
|
||
(*self.nv12).linesize.as_ptr(),
|
||
) < 0
|
||
{
|
||
bail!("sws_scale RGB→NV12 failed");
|
||
}
|
||
let mut hwf = ffi::av_frame_alloc();
|
||
if hwf.is_null() {
|
||
bail!("av_frame_alloc(hw) failed");
|
||
}
|
||
if ffi::av_hwframe_get_buffer(self.hw.frames_ref, hwf, 0) < 0 {
|
||
ffi::av_frame_free(&mut hwf);
|
||
bail!("av_hwframe_get_buffer(VAAPI) failed");
|
||
}
|
||
if ffi::av_hwframe_transfer_data(hwf, self.nv12, 0) < 0 {
|
||
ffi::av_frame_free(&mut hwf);
|
||
bail!("av_hwframe_transfer_data(→VAAPI) failed");
|
||
}
|
||
(*hwf).pts = pts;
|
||
(*hwf).pict_type = if idr {
|
||
ffi::AVPictureType::AV_PICTURE_TYPE_I
|
||
} else {
|
||
ffi::AVPictureType::AV_PICTURE_TYPE_NONE
|
||
};
|
||
let r = ffi::avcodec_send_frame(self.enc.as_mut_ptr(), hwf);
|
||
ffi::av_frame_free(&mut hwf);
|
||
if r < 0 {
|
||
bail!("avcodec_send_frame(VAAPI) failed ({r})");
|
||
}
|
||
}
|
||
Ok(())
|
||
}
|
||
}
|
||
|
||
impl Drop for CpuInner {
|
||
fn drop(&mut self) {
|
||
// SAFETY: `self.nv12` (an owned `AVFrame`) and `self.sws` (an owned `SwsContext`) are each
|
||
// freed exactly once here, guarded by `is_null()` so a never-set pointer is skipped (no double
|
||
// free). `CpuInner` owns both exclusively and `Drop` runs once. `av_frame_free` takes `&mut`
|
||
// and nulls the pointer. `self.enc`/`self.hw` are freed afterward by their own `Drop` impls;
|
||
// the encoder holds its own `av_buffer_ref`'d device/frames copies, so field-drop order is
|
||
// irrelevant to soundness.
|
||
unsafe {
|
||
if !self.nv12.is_null() {
|
||
ffi::av_frame_free(&mut self.nv12);
|
||
}
|
||
if !self.sws.is_null() {
|
||
ffi::sws_freeContext(self.sws);
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
// ---------------------------------------------------------------------------------------------
|
||
// Zero-copy dmabuf path: DRM-PRIME → hwmap(vaapi) → scale_vaapi(nv12) filter graph → encode.
|
||
// ---------------------------------------------------------------------------------------------
|
||
|
||
struct DmabufInner {
|
||
enc: encoder::video::Encoder,
|
||
/// DRM device the source dmabuf frames reference (the buffersrc's `hw_frames_ctx` device).
|
||
drm_device: *mut ffi::AVBufferRef,
|
||
/// VAAPI device driving `hwmap`/`scale_vaapi`/the encoder.
|
||
vaapi_device: *mut ffi::AVBufferRef,
|
||
/// DRM-PRIME frames context for the imported dmabufs (buffersrc input).
|
||
drm_frames: *mut ffi::AVBufferRef,
|
||
graph: *mut ffi::AVFilterGraph,
|
||
src: *mut ffi::AVFilterContext,
|
||
sink: *mut ffi::AVFilterContext,
|
||
width: u32,
|
||
height: u32,
|
||
fourcc: u32,
|
||
/// Frames submitted — drives the sampled `PUNKTFUNK_PERF` breakdown of the synchronous
|
||
/// submit (import+push vs CSC pull vs encoder send), the stage that dominates AMD/Intel
|
||
/// host latency (7.9 ms p50 at 1440p on the 780M).
|
||
frames: u64,
|
||
}
|
||
|
||
impl DmabufInner {
|
||
fn open(
|
||
codec: Codec,
|
||
format: PixelFormat,
|
||
width: u32,
|
||
height: u32,
|
||
fps: u32,
|
||
bitrate_bps: u64,
|
||
) -> Result<Self> {
|
||
let drm_fourcc = crate::zerocopy::drm_fourcc(format)
|
||
.ok_or_else(|| anyhow!("no DRM fourcc for {format:?} (VAAPI zero-copy)"))?;
|
||
let node = render_node();
|
||
// SAFETY: libav is initialized (`VaapiEncoder::open` ran `ffmpeg::init()` before
|
||
// `ensure_inner` → `DmabufInner::open`). Every raw pointer dereferenced below is either freshly
|
||
// allocated by the immediately-preceding ffmpeg call and null-checked, or an in-struct field of
|
||
// such an object:
|
||
// * `node` is a `CString` (from `render_node`) live for the whole block; its `.as_ptr()` is a
|
||
// NUL-terminated path read only during `av_hwdevice_ctx_create`.
|
||
// * `av_hwdevice_ctx_create(&mut drm_device, DRM, …)` / `…_create_derived(&mut vaapi_device,
|
||
// VAAPI, drm_device, …)`: on `r < 0` the out-param stays null and we bail (the derive path
|
||
// unrefs `drm_device` first); on success each is a non-null owned `AVBufferRef`.
|
||
// * `av_hwframe_ctx_alloc(drm_device)` → `drm_frames` (null-checked); `(*drm_frames).data` is
|
||
// its `AVHWFramesContext` payload, written before `av_hwframe_ctx_init`.
|
||
// * `avfilter_graph_alloc` → `graph` (null-checked); `avfilter_get_by_name` returns a static
|
||
// const `AVFilter` (process-lifetime) or null; `avfilter_graph_alloc_filter` allocates each
|
||
// filter ctx inside `graph`; the four are null-checked together. `inst`/arg strings are
|
||
// 'static C literals.
|
||
// * `(*hwmap/scale).hw_device_ctx = av_buffer_ref(vaapi_device)` attaches a NEW ref owned by
|
||
// the filter (freed by `avfilter_graph_free`); our `vaapi_device` ref is untouched.
|
||
// * `av_buffersink_get_hw_frames_ctx(sink)` → `nv12_ctx` is a borrowed ref owned by the sink,
|
||
// valid while `graph` lives (and `graph` is moved into the returned `DmabufInner`).
|
||
// * `open_vaapi_encoder` borrows `vaapi_device` (our live owned ref) and `nv12_ctx` (sink's
|
||
// live ref) and `av_buffer_ref`s both into the encoder.
|
||
// Every early-error path unref's the allocated buffers and frees the graph in the right order
|
||
// before bailing; on success the four `AVBufferRef`s + `graph` + `src`/`sink` are moved into
|
||
// `DmabufInner` and freed in its `Drop`. (Two non-UB leaks noted below: `av_buffersrc_*` and
|
||
// the final `?`.)
|
||
unsafe {
|
||
// DRM device (source dmabuf frames) + a VAAPI device derived from it (same GPU) for
|
||
// hwmap/scale_vaapi/the encoder.
|
||
let mut drm_device: *mut ffi::AVBufferRef = ptr::null_mut();
|
||
let r = ffi::av_hwdevice_ctx_create(
|
||
&mut drm_device,
|
||
ffi::AVHWDeviceType::AV_HWDEVICE_TYPE_DRM,
|
||
node.as_ptr(),
|
||
ptr::null_mut(),
|
||
0,
|
||
);
|
||
if r < 0 {
|
||
bail!(
|
||
"av_hwdevice_ctx_create(DRM {:?}): {}",
|
||
node,
|
||
ffmpeg::Error::from(r)
|
||
);
|
||
}
|
||
let mut vaapi_device: *mut ffi::AVBufferRef = ptr::null_mut();
|
||
let r = ffi::av_hwdevice_ctx_create_derived(
|
||
&mut vaapi_device,
|
||
ffi::AVHWDeviceType::AV_HWDEVICE_TYPE_VAAPI,
|
||
drm_device,
|
||
0,
|
||
);
|
||
if r < 0 {
|
||
ffi::av_buffer_unref(&mut drm_device);
|
||
bail!("derive VAAPI from DRM: {}", ffmpeg::Error::from(r));
|
||
}
|
||
|
||
// DRM-PRIME frames context for the imported dmabufs.
|
||
let mut drm_frames = ffi::av_hwframe_ctx_alloc(drm_device);
|
||
if drm_frames.is_null() {
|
||
ffi::av_buffer_unref(&mut vaapi_device);
|
||
ffi::av_buffer_unref(&mut drm_device);
|
||
bail!("av_hwframe_ctx_alloc(DRM) failed");
|
||
}
|
||
let fc = (*drm_frames).data as *mut ffi::AVHWFramesContext;
|
||
(*fc).format = ffi::AVPixelFormat::AV_PIX_FMT_DRM_PRIME;
|
||
(*fc).sw_format = ffi::AVPixelFormat::AV_PIX_FMT_BGR0; // packed XR24 RGB plane
|
||
(*fc).width = width as c_int;
|
||
(*fc).height = height as c_int;
|
||
if ffi::av_hwframe_ctx_init(drm_frames) < 0 {
|
||
ffi::av_buffer_unref(&mut drm_frames);
|
||
ffi::av_buffer_unref(&mut vaapi_device);
|
||
ffi::av_buffer_unref(&mut drm_device);
|
||
bail!("av_hwframe_ctx_init(DRM) failed");
|
||
}
|
||
|
||
// Filter graph: buffer(drm_prime) → hwmap=derive_device=vaapi:mode=read →
|
||
// scale_vaapi=format=nv12 → buffersink.
|
||
let mut graph = ffi::avfilter_graph_alloc();
|
||
if graph.is_null() {
|
||
ffi::av_buffer_unref(&mut drm_frames);
|
||
ffi::av_buffer_unref(&mut vaapi_device);
|
||
ffi::av_buffer_unref(&mut drm_device);
|
||
bail!("avfilter_graph_alloc failed");
|
||
}
|
||
|
||
let mk = |name: &CStr, inst: &CStr| -> *mut ffi::AVFilterContext {
|
||
let f = ffi::avfilter_get_by_name(name.as_ptr());
|
||
if f.is_null() {
|
||
return ptr::null_mut();
|
||
}
|
||
ffi::avfilter_graph_alloc_filter(graph, f, inst.as_ptr())
|
||
};
|
||
let src = mk(c"buffer", c"in");
|
||
let hwmap = mk(c"hwmap", c"map");
|
||
let scale = mk(c"scale_vaapi", c"csc");
|
||
let sink = mk(c"buffersink", c"out");
|
||
if src.is_null() || hwmap.is_null() || scale.is_null() || sink.is_null() {
|
||
ffi::avfilter_graph_free(&mut graph);
|
||
ffi::av_buffer_unref(&mut drm_frames);
|
||
ffi::av_buffer_unref(&mut vaapi_device);
|
||
ffi::av_buffer_unref(&mut drm_device);
|
||
bail!("a VAAPI filter (buffer/hwmap/scale_vaapi/buffersink) is missing");
|
||
}
|
||
// hwmap maps the DRM-PRIME input onto THIS vaapi device; scale_vaapi runs the CSC on
|
||
// it. Giving both our device (rather than `hwmap=derive_device`) keeps every surface —
|
||
// and the sink's output frames ctx the encoder adopts — on one VADisplay.
|
||
(*hwmap).hw_device_ctx = ffi::av_buffer_ref(vaapi_device);
|
||
(*scale).hw_device_ctx = ffi::av_buffer_ref(vaapi_device);
|
||
|
||
// buffersrc params: DRM-PRIME frames, the drm_frames ctx.
|
||
let par = ffi::av_buffersrc_parameters_alloc();
|
||
(*par).format = ffi::AVPixelFormat::AV_PIX_FMT_DRM_PRIME as c_int;
|
||
(*par).width = width as c_int;
|
||
(*par).height = height as c_int;
|
||
(*par).time_base = ffi::AVRational {
|
||
num: 1,
|
||
den: fps as c_int,
|
||
};
|
||
// Assign `drm_frames` BORROWED (no extra ref): `av_buffersrc_parameters_set` takes its
|
||
// own ref of `par->hw_frames_ctx` (via av_buffer_replace), and `av_free(par)` frees only
|
||
// the struct, not the ref. Our single owned `drm_frames` ref is retained, lives in
|
||
// `DmabufInner`, and is unref'd in `Drop`. Wrapping it in `av_buffer_ref` here would leak
|
||
// that extra ref every session (the persistent listener would accumulate them).
|
||
(*par).hw_frames_ctx = drm_frames;
|
||
let r = ffi::av_buffersrc_parameters_set(src, par);
|
||
ffi::av_free(par as *mut _);
|
||
if r < 0 {
|
||
ffi::avfilter_graph_free(&mut graph);
|
||
ffi::av_buffer_unref(&mut drm_frames);
|
||
ffi::av_buffer_unref(&mut vaapi_device);
|
||
ffi::av_buffer_unref(&mut drm_device);
|
||
bail!("av_buffersrc_parameters_set failed ({r})");
|
||
}
|
||
macro_rules! init {
|
||
($ctx:expr, $args:expr, $what:literal) => {{
|
||
let r = ffi::avfilter_init_str($ctx, $args);
|
||
if r < 0 {
|
||
ffi::avfilter_graph_free(&mut graph);
|
||
ffi::av_buffer_unref(&mut drm_frames);
|
||
ffi::av_buffer_unref(&mut vaapi_device);
|
||
ffi::av_buffer_unref(&mut drm_device);
|
||
bail!(concat!("init ", $what, " failed ({})"), r);
|
||
}
|
||
}};
|
||
}
|
||
init!(src, ptr::null(), "buffer");
|
||
init!(hwmap, c"mode=read".as_ptr(), "hwmap");
|
||
init!(scale, c"format=nv12".as_ptr(), "scale_vaapi");
|
||
init!(sink, ptr::null(), "buffersink");
|
||
|
||
let link = |a: *mut ffi::AVFilterContext, b: *mut ffi::AVFilterContext| -> c_int {
|
||
ffi::avfilter_link(a, 0, b, 0)
|
||
};
|
||
if link(src, hwmap) < 0 || link(hwmap, scale) < 0 || link(scale, sink) < 0 {
|
||
ffi::avfilter_graph_free(&mut graph);
|
||
ffi::av_buffer_unref(&mut drm_frames);
|
||
ffi::av_buffer_unref(&mut vaapi_device);
|
||
ffi::av_buffer_unref(&mut drm_device);
|
||
bail!("avfilter_link failed");
|
||
}
|
||
let r = ffi::avfilter_graph_config(graph, ptr::null_mut());
|
||
if r < 0 {
|
||
ffi::avfilter_graph_free(&mut graph);
|
||
ffi::av_buffer_unref(&mut drm_frames);
|
||
ffi::av_buffer_unref(&mut vaapi_device);
|
||
ffi::av_buffer_unref(&mut drm_device);
|
||
bail!("avfilter_graph_config failed ({r})");
|
||
}
|
||
|
||
// The encoder takes NV12 surfaces from the sink's output frames context.
|
||
let nv12_ctx = ffi::av_buffersink_get_hw_frames_ctx(sink);
|
||
if nv12_ctx.is_null() {
|
||
ffi::avfilter_graph_free(&mut graph);
|
||
ffi::av_buffer_unref(&mut drm_frames);
|
||
ffi::av_buffer_unref(&mut vaapi_device);
|
||
ffi::av_buffer_unref(&mut drm_device);
|
||
bail!("filter sink has no VAAPI frames context");
|
||
}
|
||
// On encoder-open failure, free the graph + our owned buffer refs before bailing (matching
|
||
// every error path above) so a failed session doesn't leak them. `nv12_ctx` is borrowed
|
||
// from the sink (owned by `graph`), so `avfilter_graph_free` reclaims it — don't unref it
|
||
// separately. On success the encoder takes its own ref of `vaapi_device`, and `drm_frames`/
|
||
// `vaapi_device`/`drm_device`/`graph` move into `DmabufInner` (freed in `Drop`).
|
||
let enc = match open_vaapi_encoder(
|
||
codec,
|
||
width,
|
||
height,
|
||
fps,
|
||
bitrate_bps,
|
||
vaapi_device,
|
||
nv12_ctx,
|
||
) {
|
||
Ok(enc) => enc,
|
||
Err(e) => {
|
||
ffi::avfilter_graph_free(&mut graph);
|
||
ffi::av_buffer_unref(&mut drm_frames);
|
||
ffi::av_buffer_unref(&mut vaapi_device);
|
||
ffi::av_buffer_unref(&mut drm_device);
|
||
return Err(e);
|
||
}
|
||
};
|
||
|
||
tracing::info!(
|
||
encoder = codec.vaapi_name(),
|
||
"VAAPI encode active ({width}x{height}@{fps}, zero-copy dmabuf → GPU NV12)"
|
||
);
|
||
Ok(DmabufInner {
|
||
enc,
|
||
drm_device,
|
||
vaapi_device,
|
||
drm_frames,
|
||
graph,
|
||
src,
|
||
sink,
|
||
width,
|
||
height,
|
||
fourcc: drm_fourcc,
|
||
frames: 0,
|
||
})
|
||
}
|
||
}
|
||
|
||
fn submit(&mut self, dmabuf: &DmabufFrame, pts: i64, idr: bool) -> Result<()> {
|
||
anyhow::ensure!(
|
||
dmabuf.fourcc == self.fourcc,
|
||
"dmabuf fourcc {:#x} != encoder {:#x}",
|
||
dmabuf.fourcc,
|
||
self.fourcc
|
||
);
|
||
// Sampled breakdown of this synchronous submit under PUNKTFUNK_PERF: push = descriptor
|
||
// build + buffersrc (the per-frame DRM→VA import happens inside hwmap on the pull path),
|
||
// pull = buffersink (VPP CSC + any sync), send = avcodec_send_frame. One line per ~2 s.
|
||
let sample = crate::config::config().perf && self.frames % 120 == 0;
|
||
self.frames += 1;
|
||
let t0 = std::time::Instant::now();
|
||
let t_push: std::time::Duration;
|
||
let t_pull: std::time::Duration;
|
||
// SAFETY: The `ensure!` above checked `dmabuf.fourcc == self.fourcc`.
|
||
// * `std::mem::zeroed::<AVDRMFrameDescriptor>()` is sound: it is a `#[repr(C)]` POD of ints and
|
||
// nested int-struct arrays (no `NonNull`/refs), for which all-zero is a valid bit pattern;
|
||
// `Box` puts it on the heap with a unique owner.
|
||
// * `dmabuf.fd.as_raw_fd()` is the fd of the caller's `&DmabufFrame`, which owns it for the
|
||
// whole synchronous `submit`; we describe one object/layer/plane from its
|
||
// fourcc/modifier/offset/stride and pass `object.size = 0` (ffmpeg queries the real size).
|
||
// * `av_frame_alloc` → `drm` (null-checked); we set its scalar fields and
|
||
// `hw_frames_ctx = av_buffer_ref(self.drm_frames)` (new ref of the live owned ctx).
|
||
// * `data[0] = Box::into_raw(desc)` transfers the box into the frame; `buf[0] =
|
||
// av_buffer_create(.., free_desc, ..)` registers a destructor that reclaims it exactly once
|
||
// when the buffer's refcount hits zero — matched alloc/free, no leak/double-free.
|
||
// * `av_buffersrc_add_frame_flags(self.src, drm, KEEP_REF)` pushes a ref into the live
|
||
// buffersrc; KEEP_REF keeps our own `drm` ref, which we then `av_frame_free`. We pull the
|
||
// converted surface with `av_buffersink_get_frame(self.sink, nv12)` BEFORE returning, so the
|
||
// dmabuf (owned by the caller) is read while still valid. `nv12` is sent into the live owned
|
||
// `self.enc` (takes its own ref) and our ref freed once. Single-threaded encoder → no race.
|
||
unsafe {
|
||
// Build a DRM-PRIME AVFrame describing the dmabuf (one object/fd, one layer/plane).
|
||
let mut desc: Box<ffi::AVDRMFrameDescriptor> = Box::new(std::mem::zeroed());
|
||
desc.nb_objects = 1;
|
||
desc.objects[0].fd = dmabuf.fd.as_raw_fd();
|
||
desc.objects[0].size = 0;
|
||
desc.objects[0].format_modifier = dmabuf.modifier;
|
||
desc.nb_layers = 1;
|
||
desc.layers[0].format = self.fourcc;
|
||
desc.layers[0].nb_planes = 1;
|
||
desc.layers[0].planes[0].object_index = 0;
|
||
desc.layers[0].planes[0].offset = dmabuf.offset as isize;
|
||
desc.layers[0].planes[0].pitch = dmabuf.stride as isize;
|
||
|
||
let mut drm = ffi::av_frame_alloc();
|
||
if drm.is_null() {
|
||
bail!("av_frame_alloc(drm) failed");
|
||
}
|
||
(*drm).format = ffi::AVPixelFormat::AV_PIX_FMT_DRM_PRIME as c_int;
|
||
(*drm).width = self.width as c_int;
|
||
(*drm).height = self.height as c_int;
|
||
(*drm).hw_frames_ctx = ffi::av_buffer_ref(self.drm_frames);
|
||
(*drm).data[0] = Box::into_raw(desc) as *mut u8;
|
||
// Own the descriptor so it frees with the frame (the fd is owned by the DmabufFrame,
|
||
// which outlives this call — the graph reads the surface before submit returns).
|
||
extern "C" fn free_desc(_opaque: *mut std::ffi::c_void, data: *mut u8) {
|
||
// SAFETY: `data` is exactly the pointer produced by `Box::into_raw(desc)` and passed as
|
||
// `av_buffer_create`'s first arg, which libav hands back verbatim to this callback. It
|
||
// is a valid, uniquely-owned `Box<AVDRMFrameDescriptor>` raw pointer; libav invokes the
|
||
// callback exactly once (when the last buffer ref drops), so `from_raw` + `drop`
|
||
// reclaims it exactly once — no double-free. `_opaque` is unused (we passed null).
|
||
unsafe { drop(Box::from_raw(data as *mut ffi::AVDRMFrameDescriptor)) };
|
||
}
|
||
(*drm).buf[0] = ffi::av_buffer_create(
|
||
(*drm).data[0],
|
||
std::mem::size_of::<ffi::AVDRMFrameDescriptor>(),
|
||
Some(free_desc),
|
||
ptr::null_mut(),
|
||
0,
|
||
);
|
||
|
||
// Push through hwmap → scale_vaapi; pull the NV12 surface back out.
|
||
let r = ffi::av_buffersrc_add_frame_flags(
|
||
self.src,
|
||
drm,
|
||
ffi::AV_BUFFERSRC_FLAG_KEEP_REF as c_int,
|
||
);
|
||
ffi::av_frame_free(&mut drm);
|
||
if r < 0 {
|
||
bail!("av_buffersrc_add_frame failed ({r})");
|
||
}
|
||
t_push = t0.elapsed();
|
||
let mut nv12 = ffi::av_frame_alloc();
|
||
if nv12.is_null() {
|
||
bail!("av_frame_alloc(nv12) failed");
|
||
}
|
||
let r = ffi::av_buffersink_get_frame(self.sink, nv12);
|
||
if r < 0 {
|
||
ffi::av_frame_free(&mut nv12);
|
||
bail!("av_buffersink_get_frame failed ({r})");
|
||
}
|
||
t_pull = t0.elapsed() - t_push;
|
||
(*nv12).pts = pts;
|
||
(*nv12).pict_type = if idr {
|
||
ffi::AVPictureType::AV_PICTURE_TYPE_I
|
||
} else {
|
||
ffi::AVPictureType::AV_PICTURE_TYPE_NONE
|
||
};
|
||
let r = ffi::avcodec_send_frame(self.enc.as_mut_ptr(), nv12);
|
||
ffi::av_frame_free(&mut nv12);
|
||
if r < 0 {
|
||
bail!("avcodec_send_frame(VAAPI) failed ({r})");
|
||
}
|
||
}
|
||
if sample {
|
||
let t_send = t0.elapsed() - t_push - t_pull;
|
||
tracing::info!(
|
||
push_us = t_push.as_micros() as u64,
|
||
pull_us = t_pull.as_micros() as u64,
|
||
send_us = t_send.as_micros() as u64,
|
||
"VAAPI submit split (sampled): push=desc+buffersrc pull=hwmap-import+VPP-CSC \
|
||
send=avcodec_send_frame"
|
||
);
|
||
}
|
||
Ok(())
|
||
}
|
||
}
|
||
|
||
impl Drop for DmabufInner {
|
||
fn drop(&mut self) {
|
||
// SAFETY: `graph`/`drm_frames`/`vaapi_device`/`drm_device` are the non-null objects
|
||
// `DmabufInner::open` built and moved into `self` (open bails before constructing `Self` if any
|
||
// alloc fails). `avfilter_graph_free` frees the graph (and the per-filter device refs it owns);
|
||
// each `av_buffer_unref` drops one ref and nulls the pointer via `&mut`. `DmabufInner` owns all
|
||
// four exclusively and `Drop` runs once → no double-free/use-after-free. The graph is freed
|
||
// first (it holds refs on the devices), then frames, then the derived VAAPI device, then DRM.
|
||
// (`self.enc` drops via ffmpeg-next afterward, holding its own refs.)
|
||
unsafe {
|
||
ffi::avfilter_graph_free(&mut self.graph);
|
||
ffi::av_buffer_unref(&mut self.drm_frames);
|
||
ffi::av_buffer_unref(&mut self.vaapi_device);
|
||
ffi::av_buffer_unref(&mut self.drm_device);
|
||
}
|
||
}
|
||
}
|
||
|
||
// ---------------------------------------------------------------------------------------------
|
||
|
||
enum Inner {
|
||
Cpu(CpuInner),
|
||
Dmabuf(DmabufInner),
|
||
}
|
||
|
||
pub struct VaapiEncoder {
|
||
codec: Codec,
|
||
format: PixelFormat,
|
||
width: u32,
|
||
height: u32,
|
||
fps: u32,
|
||
bitrate_bps: u64,
|
||
/// Built lazily from the first frame's payload (CPU upload vs zero-copy dmabuf).
|
||
inner: Option<Inner>,
|
||
frame_idx: i64,
|
||
force_kf: bool,
|
||
/// Frames sent to the encoder but not yet returned as packets. Gates [`poll`](Encoder::poll)'s
|
||
/// bounded wait: with `async_depth > 1` a submitted frame's AU lands ~ASIC-time later, so poll
|
||
/// briefly waits for it (same-tick delivery) — but only when something is actually in flight.
|
||
in_flight: u32,
|
||
}
|
||
|
||
// Raw FFI pointers; the encoder lives on a single thread (same contract as `NvencEncoder`).
|
||
// SAFETY: `VaapiEncoder`'s `Inner` holds raw FFI pointers (`SwsContext`, `AVFrame`, `AVBufferRef`,
|
||
// `AVFilterContext`, `AVCodecContext`) that are not `Send` by default. The encoder is owned and
|
||
// driven by exactly ONE thread — the host's per-session encode thread it is moved (transferred) to —
|
||
// and is only ever touched through `&mut self` methods, so it is never aliased or accessed
|
||
// concurrently from two threads. None of the underlying libav/libswscale objects have thread
|
||
// affinity (they are not thread-local), so transferring ownership across threads is sound. This
|
||
// asserts `Send` (transfer) only; `Sync` (shared `&`) is deliberately NOT implemented.
|
||
unsafe impl Send for VaapiEncoder {}
|
||
|
||
impl VaapiEncoder {
|
||
#[allow(clippy::too_many_arguments)]
|
||
pub fn open(
|
||
codec: Codec,
|
||
format: PixelFormat,
|
||
width: u32,
|
||
height: u32,
|
||
fps: u32,
|
||
bitrate_bps: u64,
|
||
bit_depth: u8,
|
||
chroma: super::ChromaFormat,
|
||
) -> Result<Self> {
|
||
if bit_depth != 8 {
|
||
tracing::warn!(bit_depth, "VAAPI 10-bit not yet wired — encoding 8-bit");
|
||
}
|
||
// VAAPI 4:4:4 is deferred (see `probe_can_encode_444`): no validated AMD/Intel hardware in the
|
||
// lab exposes a HEVC 4:4:4 encode entrypoint, and the probe returns false so the host never
|
||
// negotiates 4:4:4 for a VAAPI session. If a request slips through, fall back to 4:2:0 rather
|
||
// than emit an unverified stream — the host signalled 4:2:0 in the Welcome anyway.
|
||
if chroma.is_444() {
|
||
tracing::warn!("VAAPI 4:4:4 encode not implemented — encoding 4:2:0");
|
||
}
|
||
ffmpeg::init().context("ffmpeg init")?;
|
||
if std::env::var_os("PUNKTFUNK_FFMPEG_DEBUG").is_some() {
|
||
// SAFETY: `av_log_set_level` sets libav's global integer log level; `48` (= AV_LOG_DEBUG)
|
||
// is a valid level and there are no pointer args. libav was just initialized by the
|
||
// `ffmpeg::init()` above, so the call is always sound.
|
||
unsafe { ffi::av_log_set_level(48) };
|
||
}
|
||
// Validate the codec/format up front so a bad request fails at open, not on the first frame.
|
||
let _ = vaapi_sws_src(format)?;
|
||
Ok(VaapiEncoder {
|
||
codec,
|
||
format,
|
||
width,
|
||
height,
|
||
fps,
|
||
bitrate_bps,
|
||
inner: None,
|
||
frame_idx: 0,
|
||
force_kf: false,
|
||
in_flight: 0,
|
||
})
|
||
}
|
||
|
||
fn ensure_inner(&mut self, want_dmabuf: bool) -> Result<&mut Inner> {
|
||
if self.inner.is_none() {
|
||
let inner = if want_dmabuf {
|
||
Inner::Dmabuf(DmabufInner::open(
|
||
self.codec,
|
||
self.format,
|
||
self.width,
|
||
self.height,
|
||
self.fps,
|
||
self.bitrate_bps,
|
||
)?)
|
||
} else {
|
||
Inner::Cpu(CpuInner::open(
|
||
self.codec,
|
||
self.format,
|
||
self.width,
|
||
self.height,
|
||
self.fps,
|
||
self.bitrate_bps,
|
||
)?)
|
||
};
|
||
self.inner = Some(inner);
|
||
}
|
||
Ok(self.inner.as_mut().unwrap())
|
||
}
|
||
}
|
||
|
||
impl Encoder for VaapiEncoder {
|
||
fn submit(&mut self, captured: &CapturedFrame) -> Result<()> {
|
||
anyhow::ensure!(
|
||
captured.width == self.width && captured.height == self.height,
|
||
"captured frame {}x{} != encoder {}x{}",
|
||
captured.width,
|
||
captured.height,
|
||
self.width,
|
||
self.height
|
||
);
|
||
let pts = self.frame_idx;
|
||
self.frame_idx += 1;
|
||
let idr = self.force_kf;
|
||
self.force_kf = false;
|
||
match &captured.payload {
|
||
FramePayload::Cpu(bytes) => match self.ensure_inner(false)? {
|
||
Inner::Cpu(c) => c.submit(bytes, captured.format, pts, idr),
|
||
Inner::Dmabuf(_) => bail!("VAAPI encoder built for dmabuf got a CPU frame"),
|
||
},
|
||
FramePayload::Dmabuf(d) => match self.ensure_inner(true)? {
|
||
Inner::Dmabuf(dm) => dm.submit(d, pts, idr),
|
||
Inner::Cpu(_) => bail!("VAAPI encoder built for CPU got a dmabuf frame"),
|
||
},
|
||
FramePayload::Cuda(_) => bail!(
|
||
"VAAPI encoder received a CUDA frame — that payload is NVENC-only; \
|
||
unset PUNKTFUNK_ZEROCOPY or don't force PUNKTFUNK_ENCODER=vaapi on an NVIDIA host"
|
||
),
|
||
}?;
|
||
self.in_flight += 1;
|
||
Ok(())
|
||
}
|
||
|
||
fn request_keyframe(&mut self) {
|
||
self.force_kf = true;
|
||
}
|
||
|
||
fn poll(&mut self) -> Result<Option<EncodedFrame>> {
|
||
// With `async_depth > 1`, `submit` no longer waits for the ASIC — the AU for the frame we
|
||
// just sent lands ~one hardware-encode-time later. Wait for it (bounded) so it still ships
|
||
// this tick: the same blocking-retrieve model as NVENC's lock_bitstream, at the ASIC's
|
||
// real per-frame latency instead of send_frame's synchronous ~2× wait. The budget is 3/4
|
||
// of a frame interval (capped 12 ms); on expiry return None — the AU rides the next poll.
|
||
let enc = match &mut self.inner {
|
||
Some(Inner::Cpu(c)) => &mut c.enc,
|
||
Some(Inner::Dmabuf(d)) => &mut d.enc,
|
||
None => return Ok(None),
|
||
};
|
||
let budget = std::time::Duration::from_micros(750_000 / self.fps.max(1) as u64)
|
||
.min(std::time::Duration::from_millis(12));
|
||
let deadline = std::time::Instant::now() + budget;
|
||
loop {
|
||
if let Some(au) = poll_encoder(enc, self.fps)? {
|
||
self.in_flight = self.in_flight.saturating_sub(1);
|
||
return Ok(Some(au));
|
||
}
|
||
// Nothing ready: only wait when a frame is actually in flight (a drained/EOF'd
|
||
// encoder must not spin the budget), and give the ASIC ~250 µs between checks.
|
||
if self.in_flight == 0 || std::time::Instant::now() >= deadline {
|
||
return Ok(None);
|
||
}
|
||
std::thread::sleep(std::time::Duration::from_micros(250));
|
||
}
|
||
}
|
||
|
||
fn flush(&mut self) -> Result<()> {
|
||
match &mut self.inner {
|
||
Some(Inner::Cpu(c)) => c.enc.send_eof().context("send_eof")?,
|
||
Some(Inner::Dmabuf(d)) => d.enc.send_eof().context("send_eof")?,
|
||
None => {}
|
||
}
|
||
Ok(())
|
||
}
|
||
}
|