Quoting Kenneth Graunke (2017-07-24 02:03:23) > On Saturday, July 22, 2017 2:28:06 AM PDT Chris Wilson wrote: > > Considering the prevalence of sse4.1, another candidate is > > brw_get_buffer_subdata(), we could use a WC map there as well. > > Your thinking is...avoid polluting the CPU cache, since we're basically > going to be reading a continuous chunk of buffer data once, and never > accessing it again?
Yes, my thought is to avoid instantiating a different type of WB mmapping since we are more likely to already have a WC map of the buffer object for writing. Which avoids pulling the buffer into the CPU cache alongside the user's data - especially as the writes will not use that cache. > UC + movntdqa might be pretty reasonable there. WC doesn't buy us much > considering it's a read-only map but I guess it doesn't hurt either... One caller's UC mmap for reads is another's WC mmap for writes ;) -Chris _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
