Re: [net-next PATCH] bpf: cpumap micro-optimization in cpu_map_enqueue

2017-11-02 Thread David Miller
From: Jesper Dangaard Brouer Date: Wed, 01 Nov 2017 12:44:45 +0100 > Discovered that the compiler laid-out asm code in suboptimal way > when studying perf report during benchmarking of cpumap. Help > the compiler by the marking unlikely code paths. > > Signed-off-by: Jesper Dangaard Brouer App

Re: [net-next PATCH] bpf: cpumap micro-optimization in cpu_map_enqueue

2017-11-01 Thread Alexei Starovoitov
On Wed, Nov 01, 2017 at 12:44:45PM +0100, Jesper Dangaard Brouer wrote: > Discovered that the compiler laid-out asm code in suboptimal way > when studying perf report during benchmarking of cpumap. Help > the compiler by the marking unlikely code paths. > > Signed-off-by: Jesper Dangaard Brouer

Re: [net-next PATCH] bpf: cpumap micro-optimization in cpu_map_enqueue

2017-11-01 Thread Jesper Dangaard Brouer
On Wed, 1 Nov 2017 06:54:46 -0700 John Fastabend wrote: > On 11/01/2017 04:44 AM, Jesper Dangaard Brouer wrote: > > Discovered that the compiler laid-out asm code in suboptimal way > > when studying perf report during benchmarking of cpumap. Help > > the compiler by the marking unlikely code path

Re: [net-next PATCH] bpf: cpumap micro-optimization in cpu_map_enqueue

2017-11-01 Thread John Fastabend
On 11/01/2017 04:44 AM, Jesper Dangaard Brouer wrote: > Discovered that the compiler laid-out asm code in suboptimal way > when studying perf report during benchmarking of cpumap. Help > the compiler by the marking unlikely code paths. > > Signed-off-by: Jesper Dangaard Brouer > --- > kernel/bpf