Re: [PATCH bpf-next v2 1/2] net: xdp: refactor XDP_QUERY_PROG{,_HW} to netdev

On Fri, 31 May 2019 19:18:17 +0000, Saeed Mahameed wrote:

quoted

+	if (!bpf_op || flags & XDP_FLAGS_SKB_MODE)
+		mode = XDP_FLAGS_SKB_MODE;
+
+	curr_mode = dev_xdp_current_mode(dev);
+
+	if (!offload && curr_mode && (mode ^ curr_mode) &
+	    (XDP_FLAGS_DRV_MODE | XDP_FLAGS_SKB_MODE)) {  

if i am reading this correctly this is equivalent to :

if (!offload && (curre_mode != mode)) 
offlad is false then curr_mode and mode must be DRV or GENERIC .. 

Naw, if curr_mode is not set, i.e. nothing installed now, we don't care
about the diff.

better if you keep bitwise operations for actual bitmasks, mode and
curr_mode are not bitmask, they can hold one value each .. according to
your logic.. 

Well, they hold one bit each, whether one bit is a bitmap perhaps is
disputable? :)

I think the logic is fine.

What happened to my request to move the change in behaviour for
disabling to a separate patch, tho, Bjorn? :)