mainline inclusion
from mainline-v5.14-rc1
commit 2f128eb3
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I4CVS3
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2f128eb3308a

----------------------------------------------------------------------

Most of the time during the RX is caused by the compound_head() call
done at the end of the RX loop:

       │     build_skb():
       [...]
       │     static inline struct page *compound_head(struct page *page)
       │     {
       │     unsigned long head = READ_ONCE(page->compound_head);
 65.23 │       ldr  x2, [x1, #8]

Prefetch the page struct as soon as possible, to speedup the RX path
noticeabily by a ~3-4% packet rate in a drop test.

       │     build_skb():
       [...]
       │     static inline struct page *compound_head(struct page *page)
       │     {
       │     unsigned long head = READ_ONCE(page->compound_head);
 17.92 │       ldr  x2, [x1, #8]
Signed-off-by: NMatteo Croce <mcroce@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Reviewed-by: NYongxin Li <liyongxin1@huawei.com>
Signed-off-by: NJunxin Chen <chenjunxin1@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>