/**************************************************************************
*
* Copyright 2003 VMware, Inc.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
* IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
**************************************************************************/
/**
* @file intel_buffer_objects.c
*
* This provides core GL buffer object functionality.
*/
#include "main/imports.h"
#include "main/mtypes.h"
#include "main/macros.h"
#include "main/bufferobj.h"
#include "brw_context.h"
#include "intel_blit.h"
#include "intel_buffer_objects.h"
#include "intel_batchbuffer.h"
/**
* Map a buffer object; issue performance warnings if mapping causes stalls.
*
* This matches the drm_intel_bo_map API, but takes an additional human-readable
* name for the buffer object to use in the performance debug message.
*/
int
brw_bo_map(struct brw_context *brw,
drm_intel_bo *bo, int write_enable,
const char *bo_name)
{
if (likely(!brw->perf_debug) || !drm_intel_bo_busy(bo))
return drm_intel_bo_map(bo, write_enable);
double start_time = get_time();
int ret = drm_intel_bo_map(bo, write_enable);
perf_debug("CPU mapping a busy %s BO stalled and took %.03f ms.\n",
bo_name, (get_time() - start_time) * 1000);
return ret;
}
int
brw_bo_map_gtt(struct brw_context *brw, drm_intel_bo *bo, const char *bo_name)
{
if (likely(!brw->perf_debug) || !drm_intel_bo_busy(bo))
return drm_intel_gem_bo_map_gtt(bo);
double start_time = get_time();
int ret = drm_intel_gem_bo_map_gtt(bo);
perf_debug("GTT mapping a busy %s BO stalled and took %.03f ms.\n",
bo_name, (get_time() - start_time) * 1000);
return ret;
}
static void
mark_buffer_gpu_usage(struct intel_buffer_object *intel_obj,
uint32_t offset, uint32_t size)
{
intel_obj->gpu_active_start = MIN2(intel_obj->gpu_active_start, offset);
intel_obj->gpu_active_end = MAX2(intel_obj->gpu_active_end, offset + size);
}
static void
mark_buffer_inactive(struct intel_buffer_object *intel_obj)
{
intel_obj->gpu_active_start = ~0;
intel_obj->gpu_active_end = 0;
}
/** Allocates a new drm_intel_bo to store the data for the buffer object. */
static void
alloc_buffer_object(struct brw_context *brw,
struct intel_buffer_object *intel_obj)
{
intel_obj->buffer = drm_intel_bo_alloc(brw->bufmgr, "bufferobj",
intel_obj->Base.Size, 64);
/* the buffer might be bound as a uniform buffer, need to update it
*/
if (intel_obj->Base.UsageHistory & USAGE_UNIFORM_BUFFER)
brw->ctx.NewDriverState |= BRW_NEW_UNIFORM_BUFFER;
if (intel_obj->Base.UsageHistory & USAGE_TEXTURE_BUFFER)
brw->ctx.NewDriverState |= BRW_NEW_TEXTURE_BUFFER;
if (intel_obj->Base.UsageHistory & USAGE_ATOMIC_COUNTER_BUFFER)
brw->ctx.NewDriverState |= BRW_NEW_ATOMIC_BUFFER;
mark_buffer_inactive(intel_obj);
}
static void
release_buffer(struct intel_buffer_object *intel_obj)
{
drm_intel_bo_unreference(intel_obj->buffer);
intel_obj->buffer = NULL;
}
/**
* The NewBufferObject() driver hook.
*
* Allocates a new intel_buffer_object structure and initializes it.
*
* There is some duplication between mesa's bufferobjects and our
* bufmgr buffers. Both have an integer handle and a hashtable to
* lookup an opaque structure. It would be nice if the handles and
* internal structure where somehow shared.
*/
static struct gl_buffer_object *
brw_new_buffer_object(struct gl_context * ctx, GLuint name)
{
struct intel_buffer_object *obj = CALLOC_STRUCT(intel_buffer_object);
if (!obj) {
_mesa_error_no_memory(__func__);
}
_mesa_initialize_buffer_object(ctx, &obj->Base, name);
obj->buffer = NULL;
return &obj->Base;
}
/**
* The DeleteBuffer() driver hook.
*
* Deletes a single OpenGL buffer object. Used by glDeleteBuffers().
*/
static void
brw_delete_buffer(struct gl_context * ctx, struct gl_buffer_object *obj)
{
struct intel_buffer_object *intel_obj = intel_buffer_object(obj);
/* Buffer objects are automatically unmapped when deleting according
* to the spec, but Mesa doesn't do UnmapBuffer for us at context destroy
* (though it does if you call glDeleteBuffers)
*/
_mesa_buffer_unmap_all_mappings(ctx, obj);
drm_intel_bo_unreference(intel_obj->buffer);
}
/**
* The BufferData() driver hook.
*
* Implements glBufferData(), which recreates a buffer object's data store
* and populates it with the given data, if present.
*
* Any data that was previously stored in the buffer object is lost.
*
* \return true for success, false if out of memory
*/
static GLboolean
brw_buffer_data(struct gl_context *ctx,
GLenum target,
GLsizeiptrARB size,
const GLvoid *data,
GLenum usage,
GLbitfield storageFlags,
struct gl_buffer_object *obj)
{
struct brw_context *brw = brw_context(ctx);
struct intel_buffer_object *intel_obj = intel_buffer_object(obj);
/* Part of the ABI, but this function doesn't use it.
*/
(void) target;
intel_obj->Base.Size = size;
intel_obj->Base.Usage = usage;
intel_obj->Base.StorageFlags = storageFlags;
assert(!obj
->Mappings
[MAP_USER
].
Pointer); /* Mesa should have unmapped it */ assert(!obj
->Mappings
[MAP_INTERNAL
].
Pointer);
if (intel_obj->buffer != NULL)
release_buffer(intel_obj);
if (size != 0) {
alloc_buffer_object(brw, intel_obj);
if (!intel_obj->buffer)
return false;
if (data != NULL)
drm_intel_bo_subdata(intel_obj->buffer, 0, size, data);
}
return true;
}
/**
* The BufferSubData() driver hook.
*
* Implements glBufferSubData(), which replaces a portion of the data in a
* buffer object.
*
* If the data range specified by (size + offset) extends beyond the end of
* the buffer or if data is NULL, no copy is performed.
*/
static void
brw_buffer_subdata(struct gl_context *ctx,
GLintptrARB offset,
GLsizeiptrARB size,
const GLvoid *data,
struct gl_buffer_object *obj)
{
struct brw_context *brw = brw_context(ctx);
struct intel_buffer_object *intel_obj = intel_buffer_object(obj);
bool busy;
if (size == 0)
return;
/* See if we can unsynchronized write the data into the user's BO. This
* avoids GPU stalls in unfortunately common user patterns (uploading
* sequentially into a BO, with draw calls in between each upload).
*
* Once we've hit this path, we mark this GL BO as preferring stalling to
* blits, so that we can hopefully hit this path again in the future
* (otherwise, an app that might occasionally stall but mostly not will end
* up with blitting all the time, at the cost of bandwidth)
*/
if (offset + size <= intel_obj->gpu_active_start ||
intel_obj->gpu_active_end <= offset) {
if (brw->has_llc) {
drm_intel_gem_bo_map_unsynchronized(intel_obj->buffer);
memcpy(intel_obj
->buffer
->virtual
+ offset
, data
, size
); drm_intel_bo_unmap(intel_obj->buffer);
if (intel_obj->gpu_active_end > intel_obj->gpu_active_start)
intel_obj->prefer_stall_to_blit = true;
return;
} else {
perf_debug("BufferSubData could be unsynchronized, but !LLC doesn't support it yet\n");
}
}
busy =
drm_intel_bo_busy(intel_obj->buffer) ||
drm_intel_bo_references(brw->batch.bo, intel_obj->buffer);
if (busy) {
if (size == intel_obj->Base.Size) {
/* Replace the current busy bo so the subdata doesn't stall. */
drm_intel_bo_unreference(intel_obj->buffer);
alloc_buffer_object(brw, intel_obj);
} else if (!intel_obj->prefer_stall_to_blit) {
perf_debug("Using a blit copy to avoid stalling on "
"glBufferSubData(%ld, %ld) (%ldkb) to a busy "
"(%d-%d) buffer object.\n",
(long)offset, (long)offset + size, (long)(size/1024),
intel_obj->gpu_active_start,
intel_obj->gpu_active_end);
drm_intel_bo *temp_bo =
drm_intel_bo_alloc(brw->bufmgr, "subdata temp", size, 64);
drm_intel_bo_subdata(temp_bo, 0, size, data);
intel_emit_linear_blit(brw,
intel_obj->buffer, offset,
temp_bo, 0,
size);
drm_intel_bo_unreference(temp_bo);
return;
} else {
perf_debug("Stalling on glBufferSubData(%ld, %ld) (%ldkb) to a busy "
"(%d-%d) buffer object. Use glMapBufferRange() to "
"avoid this.\n",
(long)offset, (long)offset + size, (long)(size/1024),
intel_obj->gpu_active_start,
intel_obj->gpu_active_end);
intel_batchbuffer_flush(brw);
}
}
drm_intel_bo_subdata(intel_obj->buffer, offset, size, data);
mark_buffer_inactive(intel_obj);
}
/**
* The GetBufferSubData() driver hook.
*
* Implements glGetBufferSubData(), which copies a subrange of a buffer
* object into user memory.
*/
static void
brw_get_buffer_subdata(struct gl_context *ctx,
GLintptrARB offset,
GLsizeiptrARB size,
GLvoid *data,
struct gl_buffer_object *obj)
{
struct intel_buffer_object *intel_obj = intel_buffer_object(obj);
struct brw_context *brw = brw_context(ctx);
if (drm_intel_bo_references(brw->batch.bo, intel_obj->buffer)) {
intel_batchbuffer_flush(brw);
}
drm_intel_bo_get_subdata(intel_obj->buffer, offset, size, data);
mark_buffer_inactive(intel_obj);
}
/**
* The MapBufferRange() driver hook.
*
* This implements both glMapBufferRange() and glMapBuffer().
*
* The goal of this extension is to allow apps to accumulate their rendering
* at the same time as they accumulate their buffer object. Without it,
* you'd end up blocking on execution of rendering every time you mapped
* the buffer to put new data in.
*
* We support it in 3 ways: If unsynchronized, then don't bother
* flushing the batchbuffer before mapping the buffer, which can save blocking
* in many cases. If we would still block, and they allow the whole buffer
* to be invalidated, then just allocate a new buffer to replace the old one.
* If not, and we'd block, and they allow the subrange of the buffer to be
* invalidated, then we can make a new little BO, let them write into that,
* and blit it into the real BO at unmap time.
*/
static void *
brw_map_buffer_range(struct gl_context *ctx,
GLintptr offset, GLsizeiptr length,
GLbitfield access, struct gl_buffer_object *obj,
gl_map_buffer_index index)
{
struct brw_context *brw = brw_context(ctx);
struct intel_buffer_object *intel_obj = intel_buffer_object(obj);
/* _mesa_MapBufferRange (GL entrypoint) sets these, but the vbo module also
* internally uses our functions directly.
*/
obj->Mappings[index].Offset = offset;
obj->Mappings[index].Length = length;
obj->Mappings[index].AccessFlags = access;
if (intel_obj->buffer == NULL) {
obj->Mappings[index].Pointer = NULL;
return NULL;
}
/* If the access is synchronized (like a normal buffer mapping), then get
* things flushed out so the later mapping syncs appropriately through GEM.
* If the user doesn't care about existing buffer contents and mapping would
* cause us to block, then throw out the old buffer.
*
* If they set INVALIDATE_BUFFER, we can pitch the current contents to
* achieve the required synchronization.
*/
if (!(access & GL_MAP_UNSYNCHRONIZED_BIT)) {
if (drm_intel_bo_references(brw->batch.bo, intel_obj->buffer)) {
if (access & GL_MAP_INVALIDATE_BUFFER_BIT) {
drm_intel_bo_unreference(intel_obj->buffer);
alloc_buffer_object(brw, intel_obj);
} else {
perf_debug("Stalling on the GPU for mapping a busy buffer "
"object\n");
intel_batchbuffer_flush(brw);
}
} else if (drm_intel_bo_busy(intel_obj->buffer) &&
(access & GL_MAP_INVALIDATE_BUFFER_BIT)) {
drm_intel_bo_unreference(intel_obj->buffer);
alloc_buffer_object(brw, intel_obj);
}
}
/* If the user is mapping a range of an active buffer object but
* doesn't require the current contents of that range, make a new
* BO, and we'll copy what they put in there out at unmap or
* FlushRange time.
*
* That is, unless they're looking for a persistent mapping -- we would
* need to do blits in the MemoryBarrier call, and it's easier to just do a
* GPU stall and do a mapping.
*/
if (!(access & (GL_MAP_UNSYNCHRONIZED_BIT | GL_MAP_PERSISTENT_BIT)) &&
(access & GL_MAP_INVALIDATE_RANGE_BIT) &&
drm_intel_bo_busy(intel_obj->buffer)) {
/* Ensure that the base alignment of the allocation meets the alignment
* guarantees the driver has advertised to the application.
*/
const unsigned alignment = ctx->Const.MinMapBufferAlignment;
intel_obj->map_extra[index] = (uintptr_t) offset % alignment;
intel_obj->range_map_bo[index] = drm_intel_bo_alloc(brw->bufmgr,
"BO blit temp",
length +
intel_obj->map_extra[index],
alignment);
if (brw->has_llc) {
brw_bo_map(brw, intel_obj->range_map_bo[index],
(access & GL_MAP_WRITE_BIT) != 0, "range-map");
} else {
drm_intel_gem_bo_map_gtt(intel_obj->range_map_bo[index]);
}
obj->Mappings[index].Pointer =
intel_obj->range_map_bo[index]->virtual + intel_obj->map_extra[index];
return obj->Mappings[index].Pointer;
}
if (access & GL_MAP_UNSYNCHRONIZED_BIT) {
if (!brw->has_llc && brw->perf_debug &&
drm_intel_bo_busy(intel_obj->buffer)) {
perf_debug("MapBufferRange with GL_MAP_UNSYNCHRONIZED_BIT stalling (it's actually synchronized on non-LLC platforms)\n");
}
drm_intel_gem_bo_map_unsynchronized(intel_obj->buffer);
} else if (!brw->has_llc && (!(access & GL_MAP_READ_BIT) ||
(access & GL_MAP_PERSISTENT_BIT))) {
drm_intel_gem_bo_map_gtt(intel_obj->buffer);
mark_buffer_inactive(intel_obj);
} else {
brw_bo_map(brw, intel_obj->buffer, (access & GL_MAP_WRITE_BIT) != 0,
"MapBufferRange");
mark_buffer_inactive(intel_obj);
}
obj->Mappings[index].Pointer = intel_obj->buffer->virtual + offset;
return obj->Mappings[index].Pointer;
}
/**
* The FlushMappedBufferRange() driver hook.
*
* Implements glFlushMappedBufferRange(), which signifies that modifications
* have been made to a range of a mapped buffer, and it should be flushed.
*
* This is only used for buffers mapped with GL_MAP_FLUSH_EXPLICIT_BIT.
*
* Ideally we'd use a BO to avoid taking up cache space for the temporary
* data, but FlushMappedBufferRange may be followed by further writes to
* the pointer, so we would have to re-map after emitting our blit, which
* would defeat the point.
*/
static void
brw_flush_mapped_buffer_range(struct gl_context *ctx,
GLintptr offset, GLsizeiptr length,
struct gl_buffer_object *obj,
gl_map_buffer_index index)
{
struct brw_context *brw = brw_context(ctx);
struct intel_buffer_object *intel_obj = intel_buffer_object(obj);
assert(obj
->Mappings
[index
].
AccessFlags & GL_MAP_FLUSH_EXPLICIT_BIT
);
/* If we gave a direct mapping of the buffer instead of using a temporary,
* then there's nothing to do.
*/
if (intel_obj->range_map_bo[index] == NULL)
return;
if (length == 0)
return;
/* Note that we're not unmapping our buffer while executing the blit. We
* need to have a mapping still at the end of this call, since the user
* gets to make further modifications and glFlushMappedBufferRange() calls.
* This is safe, because:
*
* - On LLC platforms, we're using a CPU mapping that's coherent with the
* GPU (except for the render caches), so the kernel doesn't need to do
* any flushing work for us except for what happens at batch exec time
* anyway.
*
* - On non-LLC platforms, we're using a GTT mapping that writes directly
* to system memory (except for the chipset cache that gets flushed at
* batch exec time).
*
* In both cases we don't need to stall for the previous blit to complete
* so we can re-map (and we definitely don't want to, since that would be
* slow): If the user edits a part of their buffer that's previously been
* blitted, then our lack of synchoronization is fine, because either
* they'll get some too-new data in the first blit and not do another blit
* of that area (but in that case the results are undefined), or they'll do
* another blit of that area and the complete newer data will land the
* second time.
*/
intel_emit_linear_blit(brw,
intel_obj->buffer,
obj->Mappings[index].Offset + offset,
intel_obj->range_map_bo[index],
intel_obj->map_extra[index] + offset,
length);
mark_buffer_gpu_usage(intel_obj,
obj->Mappings[index].Offset + offset,
length);
}
/**
* The UnmapBuffer() driver hook.
*
* Implements glUnmapBuffer().
*/
static GLboolean
brw_unmap_buffer(struct gl_context *ctx,
struct gl_buffer_object *obj,
gl_map_buffer_index index)
{
struct brw_context *brw = brw_context(ctx);
struct intel_buffer_object *intel_obj = intel_buffer_object(obj);
assert(obj
->Mappings
[index
].
Pointer); if (intel_obj->range_map_bo[index] != NULL) {
drm_intel_bo_unmap(intel_obj->range_map_bo[index]);
if (!(obj->Mappings[index].AccessFlags & GL_MAP_FLUSH_EXPLICIT_BIT)) {
intel_emit_linear_blit(brw,
intel_obj->buffer, obj->Mappings[index].Offset,
intel_obj->range_map_bo[index],
intel_obj->map_extra[index],
obj->Mappings[index].Length);
mark_buffer_gpu_usage(intel_obj, obj->Mappings[index].Offset,
obj->Mappings[index].Length);
}
/* Since we've emitted some blits to buffers that will (likely) be used
* in rendering operations in other cache domains in this batch, emit a
* flush. Once again, we wish for a domain tracker in libdrm to cover
* usage inside of a batchbuffer.
*/
intel_batchbuffer_emit_mi_flush(brw);
drm_intel_bo_unreference(intel_obj->range_map_bo[index]);
intel_obj->range_map_bo[index] = NULL;
} else if (intel_obj->buffer != NULL) {
drm_intel_bo_unmap(intel_obj->buffer);
}
obj->Mappings[index].Pointer = NULL;
obj->Mappings[index].Offset = 0;
obj->Mappings[index].Length = 0;
return true;
}
/**
* Gets a pointer to the object's BO, and marks the given range as being used
* on the GPU.
*
* Anywhere that uses buffer objects in the pipeline should be using this to
* mark the range of the buffer that is being accessed by the pipeline.
*/
drm_intel_bo *
intel_bufferobj_buffer(struct brw_context *brw,
struct intel_buffer_object *intel_obj,
uint32_t offset, uint32_t size)
{
/* This is needed so that things like transform feedback and texture buffer
* objects that need a BO but don't want to check that they exist for
* draw-time validation can just always get a BO from a GL buffer object.
*/
if (intel_obj->buffer == NULL)
alloc_buffer_object(brw, intel_obj);
mark_buffer_gpu_usage(intel_obj, offset, size);
return intel_obj->buffer;
}
/**
* The CopyBufferSubData() driver hook.
*
* Implements glCopyBufferSubData(), which copies a portion of one buffer
* object's data to another. Independent source and destination offsets
* are allowed.
*/
static void
brw_copy_buffer_subdata(struct gl_context *ctx,
struct gl_buffer_object *src,
struct gl_buffer_object *dst,
GLintptr read_offset, GLintptr write_offset,
GLsizeiptr size)
{
struct brw_context *brw = brw_context(ctx);
struct intel_buffer_object *intel_src = intel_buffer_object(src);
struct intel_buffer_object *intel_dst = intel_buffer_object(dst);
drm_intel_bo *src_bo, *dst_bo;
if (size == 0)
return;
dst_bo = intel_bufferobj_buffer(brw, intel_dst, write_offset, size);
src_bo = intel_bufferobj_buffer(brw, intel_src, read_offset, size);
intel_emit_linear_blit(brw,
dst_bo, write_offset,
src_bo, read_offset, size);
/* Since we've emitted some blits to buffers that will (likely) be used
* in rendering operations in other cache domains in this batch, emit a
* flush. Once again, we wish for a domain tracker in libdrm to cover
* usage inside of a batchbuffer.
*/
intel_batchbuffer_emit_mi_flush(brw);
}
void
intelInitBufferObjectFuncs(struct dd_function_table *functions)
{
functions->NewBufferObject = brw_new_buffer_object;
functions->DeleteBuffer = brw_delete_buffer;
functions->BufferData = brw_buffer_data;
functions->BufferSubData = brw_buffer_subdata;
functions->GetBufferSubData = brw_get_buffer_subdata;
functions->MapBufferRange = brw_map_buffer_range;
functions->FlushMappedBufferRange = brw_flush_mapped_buffer_range;
functions->UnmapBuffer = brw_unmap_buffer;
functions->CopyBufferSubData = brw_copy_buffer_subdata;
}