A-Team_Digital_Solutions/android_kernel_motorola_sm6375
Watch
2
0
Fork
You've already forked android_kernel_motorola_sm6375
 0
mirror of https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git synced 2026-10-13 08:07:32 -04:00
Code Issues Projects Releases Packages Wiki Activity

ANDROID: staging: ion: optimize cache operation for non-cached buffer

Browse source 
The non-cached ion buffer is flushed when allocated.
And then, that is is always mapped as non-cached after allocation.
In the absence of caching, cache maintenance operations
become unnecessary. However dma_buf_ops tries to maintain
cache coherency for non-cached buffer on begin[end]_cpu_access
and map[unmap]_dma_buf functions.

It creates unnecessary overhead, so let's remove it.

Bug: 151775080

Signed-off-by: Hyesoo Yu <hyesoo.yu@samsung.com>
Change-Id: I168117c7002aec7930c84168d15816a09750b7d8
Signed-off-by: Hridya Valsaraju <hridya@google.com>
(cherry picked from commit 2c3b4cba8ab38d7eb9f474c78f9b4c70867bf71d)
Signed-off-by: Hridya Valsaraju <hridya@google.com>
This commit is contained in:
Hyesoo Yu 2020-03-20 18:54:00 +09:00 • committed by Hridya Valsaraju
commit 48675044f9
1 changed files with 18 additions and 2 deletions
Download patch file Download diff file Expand all files Collapse all files

20
drivers/staging/android/ion/ion_dma_buf.c
View file

@ -105,6 +105,7 @@ static struct sg_table *ion_map_dma_buf(struct dma_buf_attachment *attachment,
struct ion_heap *heap = buffer->heap;
struct ion_dma_buf_attachment *a;
struct sg_table *table;
unsigned long attrs = attachment->dma_map_attrs;
if (heap->buf_ops.map_dma_buf)
return heap->buf_ops.map_dma_buf(attachment, direction);
@ -112,8 +113,11 @@ static struct sg_table *ion_map_dma_buf(struct dma_buf_attachment *attachment,
a = attachment->priv;
table = a->table;
if (!(buffer->flags & ION_FLAG_CACHED))
attrs |= DMA_ATTR_SKIP_CPU_SYNC;
if (!dma_map_sg_attrs(attachment->dev, table->sgl, table->nents,
direction, attachment->dma_map_attrs))
direction, attrs))
return ERR_PTR(-ENOMEM);
a->mapped = true;
@ -128,6 +132,7 @@ static void ion_unmap_dma_buf(struct dma_buf_attachment *attachment,
struct ion_buffer *buffer = attachment->dmabuf->priv;
struct ion_heap *heap = buffer->heap;
struct ion_dma_buf_attachment *a = attachment->priv;
unsigned long attrs = attachment->dma_map_attrs;
a->mapped = false;
@ -135,8 +140,11 @@ static void ion_unmap_dma_buf(struct dma_buf_attachment *attachment,
return heap->buf_ops.unmap_dma_buf(attachment, table,
direction);
if (!(buffer->flags & ION_FLAG_CACHED))
attrs |= DMA_ATTR_SKIP_CPU_SYNC;
dma_unmap_sg_attrs(attachment->dev, table->sgl, table->nents,
direction, attachment->dma_map_attrs);
direction, attrs);
}
static void ion_dma_buf_release(struct dma_buf *dmabuf)
@ -174,6 +182,9 @@ static int ion_dma_buf_begin_cpu_access(struct dma_buf *dmabuf,
goto unlock;
}
if (!(buffer->flags & ION_FLAG_CACHED))
goto unlock;
list_for_each_entry(a, &buffer->attachments, list) {
if (!a->mapped)
continue;
@ -218,12 +229,17 @@ static int ion_dma_buf_end_cpu_access(struct dma_buf *dmabuf,
mutex_lock(&buffer->lock);
ion_buffer_kmap_put(buffer);
if (!(buffer->flags & ION_FLAG_CACHED))
goto unlock;
list_for_each_entry(a, &buffer->attachments, list) {
if (!a->mapped)
continue;
dma_sync_sg_for_device(a->dev, a->table->sgl, a->table->nents,
direction);
}
unlock:
mutex_unlock(&buffer->lock);
return 0;