drm/radeon/kms: attempt to avoid copying data twice on coherent cards. (v3)

On coherent systems (not-AGP) the IB should be in cached memory so should
be just as fast, so we can avoid copying to temporary pages and just use it
directly.

provides minor speedups on rv530: gears ~1820->1860, ipers: 29.9->30.6,
but always good to use less CPU if we can.

v3: cleanup unneeded bits.

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

diff --git a/drivers/gpu/drm/radeon/radeon_cs.c b/drivers/gpu/drm/radeon/radeon_cs.c
index 5cac8327833840d5b2503d0e8dd028b283d858a7..e7b0b5d51bc3813b46885978f942764f5041e0e0 100644 (file)
--- a/drivers/gpu/drm/radeon/radeon_cs.c
+++ b/drivers/gpu/drm/radeon/radeon_cs.c
@@ -278,11 +278,16 @@ int radeon_cs_parser_init(struct radeon_cs_parser *p, void *data)
                                  p->chunks[p->chunk_ib_idx].length_dw);
                        return -EINVAL;
                }
-               p->chunks[p->chunk_ib_idx].kpage[0] = kmalloc(PAGE_SIZE, GFP_KERNEL);
-               p->chunks[p->chunk_ib_idx].kpage[1] = kmalloc(PAGE_SIZE, GFP_KERNEL);
-               if (p->chunks[p->chunk_ib_idx].kpage[0] == NULL ||
-                   p->chunks[p->chunk_ib_idx].kpage[1] == NULL)
-                       return -ENOMEM;
+               if ((p->rdev->flags & RADEON_IS_AGP)) {
+                       p->chunks[p->chunk_ib_idx].kpage[0] = kmalloc(PAGE_SIZE, GFP_KERNEL);
+                       p->chunks[p->chunk_ib_idx].kpage[1] = kmalloc(PAGE_SIZE, GFP_KERNEL);
+                       if (p->chunks[p->chunk_ib_idx].kpage[0] == NULL ||
+                           p->chunks[p->chunk_ib_idx].kpage[1] == NULL) {
+                               kfree(p->chunks[i].kpage[0]);
+                               kfree(p->chunks[i].kpage[1]);
+                               return -ENOMEM;
+                       }
+               }
                p->chunks[p->chunk_ib_idx].kpage_idx[0] = -1;
                p->chunks[p->chunk_ib_idx].kpage_idx[1] = -1;
                p->chunks[p->chunk_ib_idx].last_copied_page = -1;
@@ -323,8 +328,10 @@ static void radeon_cs_parser_fini(struct radeon_cs_parser *parser, int error)
        kfree(parser->relocs_ptr);
        for (i = 0; i < parser->nchunks; i++) {
                kfree(parser->chunks[i].kdata);
-               kfree(parser->chunks[i].kpage[0]);
-               kfree(parser->chunks[i].kpage[1]);
+               if ((parser->rdev->flags & RADEON_IS_AGP)) {
+                       kfree(parser->chunks[i].kpage[0]);
+                       kfree(parser->chunks[i].kpage[1]);
+               }
        }
        kfree(parser->chunks);
        kfree(parser->chunks_array);
@@ -573,6 +580,7 @@ int radeon_cs_update_pages(struct radeon_cs_parser *p, int pg_idx)
        struct radeon_cs_chunk *ibc = &p->chunks[p->chunk_ib_idx];
        int i;
        int size = PAGE_SIZE;
+       bool copy1 = (p->rdev->flags & RADEON_IS_AGP) ? false : true;
 
        for (i = ibc->last_copied_page + 1; i < pg_idx; i++) {
                if (DRM_COPY_FROM_USER(p->ib->ptr + (i * (PAGE_SIZE/4)),
@@ -583,14 +591,16 @@ int radeon_cs_update_pages(struct radeon_cs_parser *p, int pg_idx)
                }
        }
 
-       new_page = ibc->kpage_idx[0] < ibc->kpage_idx[1] ? 0 : 1;
-
        if (pg_idx == ibc->last_page_index) {
                size = (ibc->length_dw * 4) % PAGE_SIZE;
-                       if (size == 0)
-                               size = PAGE_SIZE;
+               if (size == 0)
+                       size = PAGE_SIZE;
        }
 
+       new_page = ibc->kpage_idx[0] < ibc->kpage_idx[1] ? 0 : 1;
+       if (copy1)
+               ibc->kpage[new_page] = p->ib->ptr + (pg_idx * (PAGE_SIZE / 4));
+
        if (DRM_COPY_FROM_USER(ibc->kpage[new_page],
                               ibc->user_ptr + (pg_idx * PAGE_SIZE),
                               size)) {
@@ -598,8 +608,9 @@ int radeon_cs_update_pages(struct radeon_cs_parser *p, int pg_idx)
                return 0;
        }
 
-       /* copy to IB here */
-       memcpy((void *)(p->ib->ptr+(pg_idx*(PAGE_SIZE/4))), ibc->kpage[new_page], size);
+       /* copy to IB for non single case */
+       if (!copy1)
+               memcpy((void *)(p->ib->ptr+(pg_idx*(PAGE_SIZE/4))), ibc->kpage[new_page], size);
 
        ibc->last_copied_page = pg_idx;
        ibc->kpage_idx[new_page] = pg_idx;