Dan Williams <dan.j.williams@xxxxxxxxx> writes: > When I read your patch I came away with the impression that ARM had > not added memcpy_flushcache() yet and you were working around that > fact. Now that I look, ARM *does* define memcpy_flushcache() and > you're avoiding it. You use memcpy+arch_wb_pmem where arch_wb_pmem on > ARM64 is defined as __clean_dcache_area_pop(dst, cnt). The ARM > memcpy_flushcache() implementation is: > > memcpy(dst, src, cnt); > __clean_dcache_area_pop(dst, cnt); > > So, I do not see how what you're doing is any less work unless you are > flushing less than you copy? > > If memcpy_flushcache() is slower than memcpy + arch_wb_pmem then the > ARM implementation is broken and that needs to be addressed not worked > around in a driver. I think Mikulas wanted to batch up multiple copies and flush at the end. According to his commit message, that batching gained him 2% performance. -Jeff -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
