net: skbuff: move alloc_cpu into a potential hole

alloc_cpu is currently between 4 byte fields, so it's almost
guaranteed to create a 2B hole. It has a knock on effect of
creating a 4B hole after @end (and @end and @tail being in
different cachelines).

None of this matters hugely, but for kernel configs which
don't enable all the features there may well be a 2B hole
after the bitfield. Move alloc_cpu there.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 98d6b48f4dcf6346ea627b311e0487ecdc511368..2595b2cfba0d42348f647a0acad727aa46e70422 100644 (file)
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -991,6 +991,8 @@ struct sk_buff {
        __u16                   tc_index;       /* traffic control index */
 #endif
 
+       u16                     alloc_cpu;
+
        union {
                __wsum          csum;
                struct {
@@ -1014,7 +1016,6 @@ struct sk_buff {
                unsigned int    sender_cpu;
        };
 #endif
-       u16                     alloc_cpu;
 #ifdef CONFIG_NETWORK_SECMARK
        __u32           secmark;
 #endif