On date Monday 2015-05-18 13:26:56 +0200, Stefano Sabatini encoded:
> On Mon, May 18, 2015 at 1:17 PM, Hendrik Leppkes <h.lepp...@gmail.com>
> wrote:
>
> > On Mon, May 18, 2015 at 12:37 PM, Stefano Sabatini <stefa...@gmail.com>
> > wrote:
> >
> [...]
>
> > >
> > > I have a first hackish patch, performed some tests and I got some
> > > significant performance gains, on my iCore5 with Intel Graphics HD4000 I
> > > have now the same performance as the software decoder using DXVA2 for
> > > decoding a H.264 1920x1080 video, but using only a single thread. The
> > patch
> > > as is is a hack, since I had to modify the compilation flags to enable
> > > assembly compilation in the ffmpeg_dxva2.c file. I should probably create
> > > an optimized copy function in libavutil, comments are welcome.
> >
> > FWIW, I never saw any benefits from using a small cache over simply
> > copying directly to the destination memory, that could potentially
> > simplify this a bit.
> >
>
>
> > And yeah, its a huge hack, we don't want new inline assembly.
> >
>
> The sanest approach is probably to add a function to libavutil. The
> optimized copy would then be accessible to third-party library users, with
> no assembly hacks involved.
New patch attached, it's still somehow hackish, please advice if you
consider this approach acceptable.
--
FFmpeg = Formidable and Friendly MultiPurpose Explosive Game
>From f3b4e77dd9dd299aba8f4fa83625d2b61b243c3c Mon Sep 17 00:00:00 2001
From: Stefano Sabatini <stefa...@gmail.com>
Date: Fri, 15 May 2015 18:58:17 +0200
Subject: [PATCH] lavu/imgutils: add av_image_copy_plane_from_uswc() function.
This function allows support to optimized GPU to CPU.
Based on code from vlc dxva2.c, commit 62107e56 by Laurent Aimar
<fen...@videolan.org>.
TODO: fix integration with the build system, bump micro
Signed-off-by: Stefano Sabatini <stefa...@gmail.com>
---
libavutil/imgutils.c | 14 ++++++
libavutil/imgutils.h | 18 +++++++
libavutil/imgutils_internal.h | 29 +++++++++++
libavutil/x86/Makefile | 1 +
libavutil/x86/imgutils.c | 109 ++++++++++++++++++++++++++++++++++++++++++
5 files changed, 171 insertions(+)
create mode 100644 libavutil/imgutils_internal.h
create mode 100644 libavutil/x86/imgutils.c
diff --git a/libavutil/imgutils.c b/libavutil/imgutils.c
index ef0e671..e538c75 100644
--- a/libavutil/imgutils.c
+++ b/libavutil/imgutils.c
@@ -30,6 +30,7 @@
#include "mathematics.h"
#include "pixdesc.h"
#include "rational.h"
+#include "imgutils_internal.h"
void av_image_fill_max_pixsteps(int max_pixsteps[4], int max_pixstep_comps[4],
const AVPixFmtDescriptor *pixdesc)
@@ -405,3 +406,16 @@ int av_image_copy_to_buffer(uint8_t *dst, int dst_size,
return size;
}
+
+void av_image_copy_plane_from_uswc(uint8_t *dst, size_t dst_linesize,
+ const uint8_t *src, size_t src_linesize,
+ unsigned bytewidth, unsigned height,
+ unsigned cpu_flags)
+{
+#ifndef HAVE_SSSE3
+ av_unused(cpu_flags);
+ av_image_copy_plane(dst, dst_linesize, src, src_linesize, bytewidth, height);
+#else
+ ff_image_copy_plane_from_uswc_x86(dst, dst_linesize, src, src_linesize, bytewidth, height, cpu_flags);
+#endif
+}
diff --git a/libavutil/imgutils.h b/libavutil/imgutils.h
index 23282a3..82c3826 100644
--- a/libavutil/imgutils.h
+++ b/libavutil/imgutils.h
@@ -111,6 +111,24 @@ void av_image_copy_plane(uint8_t *dst, int dst_linesize,
int bytewidth, int height);
/**
+ * Copy image plane from src to dst, similar to av_image_copy_plane().
+ * src must be an USWC buffer.
+ * It performs optimized copy from "Uncacheable Speculative Write
+ * Combining" memory as used by some video surface.
+ * It is really efficient only when SSE4.1 is available.
+ *
+ * In case the target CPU does not support USWC caching this function
+ * will be equivalent to av_image_copy_plane().
+ *
+ * @param cpu_flags as returned by av_get_cpu_flags()
+ * @see av_image_copy_plane()
+ */
+void av_image_copy_plane_from_uswc(uint8_t *dst, size_t dst_linesize,
+ const uint8_t *src, size_t src_linesize,
+ unsigned bytewidth, unsigned height,
+ unsigned cpu_flags);
+
+/**
* Copy image in src_data to dst_data.
*
* @param dst_linesizes linesizes for the image in dst_data
diff --git a/libavutil/imgutils_internal.h b/libavutil/imgutils_internal.h
new file mode 100644
index 0000000..16ed977
--- /dev/null
+++ b/libavutil/imgutils_internal.h
@@ -0,0 +1,29 @@
+/*
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVUTIL_IMGUTILS_INTERNAL_H
+#define AVUTIL_IMGUTILS_INTERNAL_H
+
+#include "imgutils.h"
+
+void ff_image_copy_plane_from_uswc_x86(uint8_t *dst, size_t dst_linesize,
+ const uint8_t *src, size_t src_linesize,
+ unsigned bytewidth, unsigned height,
+ unsigned cpu_flags);
+
+#endif /* AVUTIL_IMGUTILS_INTERNAL_H */
diff --git a/libavutil/x86/Makefile b/libavutil/x86/Makefile
index eb70a62..a719c00 100644
--- a/libavutil/x86/Makefile
+++ b/libavutil/x86/Makefile
@@ -1,5 +1,6 @@
OBJS += x86/cpu.o \
x86/float_dsp_init.o \
+ x86/imgutils.o \
x86/lls_init.o \
OBJS-$(CONFIG_PIXELUTILS) += x86/pixelutils_init.o \
diff --git a/libavutil/x86/imgutils.c b/libavutil/x86/imgutils.c
new file mode 100644
index 0000000..91c7a42
--- /dev/null
+++ b/libavutil/x86/imgutils.c
@@ -0,0 +1,109 @@
+/*
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <inttypes.h>
+#include "config.h"
+#include "libavutil/attributes.h"
+#include "libavutil/avassert.h"
+#include "libavutil/intreadwrite.h"
+#include "libavutil/x86/asm.h"
+#include "libavutil/x86/cpu.h"
+#include "libavutil/cpu.h"
+#include "libavutil/pixdesc.h"
+
+#include "libavutil/avassert.h"
+#include "libavutil/x86/asm.h"
+#include "libavutil/imgutils.h"
+#include "libavutil/imgutils_internal.h"
+
+#ifdef HAVE_SSE2
+/* Copy 16/64 bytes from srcp to dstp loading data with the SSE>=2 instruction
+ * load and storing data with the SSE>=2 instruction store.
+ */
+#define COPY16(dstp, srcp, load, store) \
+ __asm__ volatile ( \
+ load " 0(%[src]), %%xmm1\n" \
+ store " %%xmm1, 0(%[dst])\n" \
+ : : [dst]"r"(dstp), [src]"r"(srcp) : "memory", "xmm1")
+
+#define COPY64(dstp, srcp, load, store) \
+ __asm__ volatile ( \
+ load " 0(%[src]), %%xmm1\n" \
+ load " 16(%[src]), %%xmm2\n" \
+ load " 32(%[src]), %%xmm3\n" \
+ load " 48(%[src]), %%xmm4\n" \
+ store " %%xmm1, 0(%[dst])\n" \
+ store " %%xmm2, 16(%[dst])\n" \
+ store " %%xmm3, 32(%[dst])\n" \
+ store " %%xmm4, 48(%[dst])\n" \
+ : : [dst]"r"(dstp), [src]"r"(srcp) : "memory", "xmm1", "xmm2", "xmm3", "xmm4")
+#endif
+
+#define AV_CPU_SSE4() ((cpu_flags & AV_CPU_FLAG_SSE4) != 0)
+#define AV_CPU_SSSE3() ((cpu_flags & AV_CPU_FLAG_SSSE3) != 0)
+#define AV_CPU_SSE2() ((cpu_flags & AV_CPU_FLAG_SSE2) != 0)
+
+void ff_image_copy_plane_from_uswc_x86(uint8_t *dst, size_t dst_linesize,
+ const uint8_t *src, size_t src_linesize,
+ unsigned bytewidth, unsigned height,
+ unsigned cpu_flags)
+{
+#ifndef HAVE_SSSE3
+ av_unused(cpu_flags);
+ return av_copy_plane(dst, dst_linesize, src, src_linesize, bytewidth, height);
+#endif
+
+ av_assert0(((intptr_t)dst & 0x0f) == 0 && (dst_linesize & 0x0f) == 0);
+
+ __asm__ volatile ("mfence");
+
+ for (unsigned y = 0; y < height; y++) {
+ const unsigned unaligned = (-(uintptr_t)src) & 0x0f;
+ unsigned x = unaligned;
+
+#ifdef HAVE_SSE42
+ if (AV_CPU_SSE4()) {
+ if (!unaligned) {
+ for (; x+63 < bytewidth; x += 64)
+ COPY64(&dst[x], &src[x], "movntdqa", "movdqa");
+ } else {
+ COPY16(dst, src, "movdqu", "movdqa");
+ for (; x+63 < bytewidth; x += 64)
+ COPY64(&dst[x], &src[x], "movntdqa", "movdqu");
+ }
+ } else
+#endif
+ {
+ if (!unaligned) {
+ for (; x+63 < bytewidth; x += 64)
+ COPY64(&dst[x], &src[x], "movdqa", "movdqa");
+ } else {
+ COPY16(dst, src, "movdqu", "movdqa");
+ for (; x+63 < bytewidth; x += 64)
+ COPY64(&dst[x], &src[x], "movdqa", "movdqu");
+ }
+ }
+
+ for (; x < bytewidth; x++)
+ dst[x] = src[x];
+
+ src += src_linesize;
+ dst += dst_linesize;
+ }
+ __asm__ volatile ("mfence");
+}
--
1.9.1
>From 337a3ecc47873a6e7a279509f2f5a00c7cc5726f Mon Sep 17 00:00:00 2001
From: Stefano Sabatini <stefa...@gmail.com>
Date: Thu, 28 May 2015 19:26:16 +0200
Subject: [PATCH] ffmpeg_dxva2: use optimized copy function from GPU to CPU
This should allow significant improved performances.
---
ffmpeg_dxva2.c | 17 ++++++++++-------
1 file changed, 10 insertions(+), 7 deletions(-)
diff --git a/ffmpeg_dxva2.c b/ffmpeg_dxva2.c
index 6b20195..34e4643 100644
--- a/ffmpeg_dxva2.c
+++ b/ffmpeg_dxva2.c
@@ -258,7 +258,9 @@ static int dxva2_retrieve_data(AVCodecContext *s, AVFrame *frame)
D3DLOCKED_RECT LockedRect;
HRESULT hr;
int ret;
+ int cpu_flags;
+ cpu_flags = av_get_cpu_flags();
IDirect3DSurface9_GetDesc(surface, &surfaceDesc);
ctx->tmp_frame->width = frame->width;
@@ -275,14 +277,15 @@ static int dxva2_retrieve_data(AVCodecContext *s, AVFrame *frame)
return AVERROR_UNKNOWN;
}
- av_image_copy_plane(ctx->tmp_frame->data[0], ctx->tmp_frame->linesize[0],
- (uint8_t*)LockedRect.pBits,
- LockedRect.Pitch, frame->width, frame->height);
-
- av_image_copy_plane(ctx->tmp_frame->data[1], ctx->tmp_frame->linesize[1],
- (uint8_t*)LockedRect.pBits + LockedRect.Pitch * surfaceDesc.Height,
- LockedRect.Pitch, frame->width, frame->height / 2);
+ av_image_copy_plane_from_uswc(ctx->tmp_frame->data[0], ctx->tmp_frame->linesize[0],
+ (uint8_t*)LockedRect.pBits,
+ LockedRect.Pitch, frame->width, frame->height,
+ cpu_flags);
+ av_image_copy_plane_from_uswc(ctx->tmp_frame->data[1], ctx->tmp_frame->linesize[1],
+ (uint8_t*)LockedRect.pBits + LockedRect.Pitch * surfaceDesc.Height,
+ LockedRect.Pitch, frame->width, frame->height / 2,
+ cpu_flags);
IDirect3DSurface9_UnlockRect(surface);
ret = av_frame_copy_props(ctx->tmp_frame, frame);
--
1.9.1
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