> ^^^ Luca, I've never seen this show up high on a profile (yet). Do you see > that with Nouveau? I used to have an rb-tree implementation of drm_mm_xxx > lying around, but I didn't use it because I didn't have a case where it > showed up?
Yes, before I did userspace allocation, in doom3 profiles, get_unmapped_area and function called by it (all coming from sys_mmap) consumed around 10% of the time. Note that this is not DRM-specific code, but rather the generic Linux code for finding free virtual address space, which walks over all the vmas in the process and, in the default x86 variant, does an rb-tree lookup for each vma! It could be fixed by either in the kernel with better data structures and algorithms or in userspace by using MAP_FIXED. However, this will still leave significant kernel overhead (e.g. just drm_mm_search_free_in_range takes 1%). ------------------------------------------------------------------------------ Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev -- _______________________________________________ Dri-devel mailing list Dri-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dri-devel
