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Matteo Croce d8ea89fe8a mvpp2: prefetch right address
In the RX buffer, the received data starts after a headroom used to
align the IP header and to allow prepending headers efficiently.
The prefetch() should take this into account, and prefetch from
the very start of the received data.

We can see that ether_addr_equal_64bits(), which is the first function
to access the data, drops from the top of the perf top output.

prefetch(data):

Overhead  Shared Object     Symbol
  11.64%  [kernel]          [k] eth_type_trans

prefetch(data + MVPP2_MH_SIZE + MVPP2_SKB_HEADROOM):

Overhead  Shared Object     Symbol
  13.42%  [kernel]          [k] build_skb
  10.35%  [mvpp2]           [k] mvpp2_rx
   9.35%  [kernel]          [k] __netif_receive_skb_core
   8.24%  [kernel]          [k] kmem_cache_free
   7.97%  [kernel]          [k] dev_gro_receive
   7.68%  [kernel]          [k] page_pool_put_page
   7.32%  [kernel]          [k] kmem_cache_alloc
   7.09%  [mvpp2]           [k] mvpp2_bm_pool_put
   3.36%  [kernel]          [k] eth_type_trans

Also, move the eth_type_trans() call a bit down, to give the RAM more
time to prefetch the data.

Signed-off-by: Matteo Croce <mcroce@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-09 15:26:50 -07:00
arch Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-05-27 09:55:10 -07:00
block block-5.13-2021-05-22 2021-05-22 07:40:34 -10:00
certs
crypto
Documentation net: ena: fix RST format in ENA documentation file 2021-06-08 14:41:09 -07:00
drivers mvpp2: prefetch right address 2021-06-09 15:26:50 -07:00
fs proc: Check /proc/$pid/attr/ writes against file opener 2021-05-25 10:24:41 -10:00
include Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next 2021-06-09 14:50:35 -07:00
init Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2021-05-11 16:05:56 -07:00
ipc ipc/mqueue, msg, sem: avoid relying on a stack reference past its expiry 2021-05-22 15:09:07 -10:00
kernel Merge ra.kernel.org:/pub/scm/linux/kernel/git/netdev/net 2021-06-07 13:01:52 -07:00
lib lib: kunit: suppress a compilation warning of frame size 2021-05-22 15:09:07 -10:00
LICENSES
mm userfaultfd: hugetlbfs: fix new flag usage in error path 2021-05-22 15:09:07 -10:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next 2021-06-09 14:50:35 -07:00
samples samples: pktgen: add UDP tx checksum support 2021-05-28 14:52:13 -07:00
scripts kbuild: Quote OBJCOPY var to avoid a pahole call break the build 2021-05-27 11:32:56 -07:00
security trusted-keys: match tpm_get_ops on all return paths 2021-05-12 22:36:37 +03:00
sound sound fixes for 5.13-rc3 2021-05-20 06:42:21 -10:00
tools selftests: devlink_lib: Fix bouncing of netdevsim DEVLINK_DEV 2021-06-08 14:39:07 -07:00
usr
virt
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap Merge drm/drm-fixes into drm-misc-fixes 2021-05-11 13:35:52 +02:00
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS Revert "nvme-tcp-offload: ULP Series" 2021-06-09 14:57:23 -07:00
Makefile Linux 5.13-rc3 2021-05-23 11:42:48 -10:00
README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.