From d2a84a76a3b970fa32e6eda3d85e7782f831379e Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 28 Oct 2016 13:58:34 +0100 Subject: [PATCH] drm/i915: Use radixtree to jump start intel_partial_pages() We can use the radixtree index of the obj->pages to find the start position of the desired partial range. Signed-off-by: Chris Wilson Reviewed-by: Tvrtko Ursulin Link: http://patchwork.freedesktop.org/patch/msgid/20161028125858.23563-11-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_gem_gtt.c | 40 +++++++++++++++++++---------- 1 file changed, 26 insertions(+), 14 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index 2bbbda191e93..b3f341fe77bf 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -3584,35 +3584,47 @@ intel_partial_pages(const struct i915_ggtt_view *view, struct drm_i915_gem_object *obj) { struct sg_table *st; - struct scatterlist *sg; - struct sg_page_iter obj_sg_iter; + struct scatterlist *sg, *iter; + unsigned int count = view->params.partial.size; + unsigned int offset; int ret = -ENOMEM; st = kmalloc(sizeof(*st), GFP_KERNEL); if (!st) goto err_st_alloc; - ret = sg_alloc_table(st, view->params.partial.size, GFP_KERNEL); + ret = sg_alloc_table(st, count, GFP_KERNEL); if (ret) goto err_sg_alloc; + iter = i915_gem_object_get_sg(obj, + view->params.partial.offset, + &offset); + GEM_BUG_ON(!iter); + sg = st->sgl; st->nents = 0; - for_each_sg_page(obj->pages->sgl, &obj_sg_iter, obj->pages->nents, - view->params.partial.offset) - { - if (st->nents >= view->params.partial.size) - break; + do { + unsigned int len; - sg_set_page(sg, NULL, PAGE_SIZE, 0); - sg_dma_address(sg) = sg_page_iter_dma_address(&obj_sg_iter); - sg_dma_len(sg) = PAGE_SIZE; + len = min(iter->length - (offset << PAGE_SHIFT), + count << PAGE_SHIFT); + sg_set_page(sg, NULL, len, 0); + sg_dma_address(sg) = + sg_dma_address(iter) + (offset << PAGE_SHIFT); + sg_dma_len(sg) = len; - sg = sg_next(sg); st->nents++; - } + count -= len >> PAGE_SHIFT; + if (count == 0) { + sg_mark_end(sg); + return st; + } - return st; + sg = __sg_next(sg); + iter = __sg_next(iter); + offset = 0; + } while (1); err_sg_alloc: kfree(st); -- 2.39.5