Re: [PATCH bpf-next 5/5] bpf: cpumap memory prefetchw optimizations for struct page

On Wed, Apr 10, 2019 at 01:43:58PM +0200, Jesper Dangaard Brouer wrote: > A lot of the performance gain comes from this patch. > > While analysing performance overhead it was found that the largest CPU > stalls were caused when touching the struct page area. It is first read with > a READ_ONCE fro

Re: [PATCH bpf-next 5/5] bpf: cpumap memory prefetchw optimizations for struct page

On Wed, Apr 10, 2019 at 6:02 AM Jesper Dangaard Brouer wrote: > > A lot of the performance gain comes from this patch. > > While analysing performance overhead it was found that the largest CPU > stalls were caused when touching the struct page area. It is first read with > a READ_ONCE from build_

[PATCH bpf-next 5/5] bpf: cpumap memory prefetchw optimizations for struct page

A lot of the performance gain comes from this patch. While analysing performance overhead it was found that the largest CPU stalls were caused when touching the struct page area. It is first read with a READ_ONCE from build_skb_around via page_is_pfmemalloc(), and when freed written by page_frag_f