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Matteo Croce e4017570da mvneta: recycle buffers
Use the new recycling API for page_pool.
In a drop rate test, the packet rate increased by 10%,
from 296 Kpps to 326 Kpps.

perf top on a stock system shows:

Overhead  Shared Object     Symbol
  23.66%  [kernel]          [k] __pi___inval_dcache_area
  22.85%  [mvneta]          [k] mvneta_rx_swbm
   7.54%  [kernel]          [k] kmem_cache_alloc
   6.49%  [kernel]          [k] eth_type_trans
   3.94%  [kernel]          [k] dev_gro_receive
   3.91%  [kernel]          [k] __netif_receive_skb_core
   3.91%  [kernel]          [k] kmem_cache_free
   3.76%  [kernel]          [k] page_pool_release_page
   3.56%  [kernel]          [k] free_unref_page
   2.40%  [kernel]          [k] build_skb
   1.49%  [kernel]          [k] skb_release_data
   1.45%  [kernel]          [k] __alloc_pages_bulk
   1.30%  [kernel]          [k] page_frag_free

And this is the same output with recycling enabled:

Overhead  Shared Object     Symbol
  26.41%  [kernel]          [k] __pi___inval_dcache_area
  25.00%  [mvneta]          [k] mvneta_rx_swbm
   8.14%  [kernel]          [k] kmem_cache_alloc
   6.84%  [kernel]          [k] eth_type_trans
   4.44%  [kernel]          [k] __netif_receive_skb_core
   4.38%  [kernel]          [k] kmem_cache_free
   4.16%  [kernel]          [k] dev_gro_receive
   3.21%  [kernel]          [k] page_pool_put_page
   2.41%  [kernel]          [k] build_skb
   1.82%  [kernel]          [k] skb_release_data
   1.61%  [kernel]          [k] napi_gro_receive
   1.25%  [kernel]          [k] page_pool_refill_alloc_cache
   1.16%  [kernel]          [k] __netif_receive_skb_list_core

We can see that page_pool_release_page(), free_unref_page() and
__alloc_pages_bulk() are no longer on top of the list when receiving
traffic.

The test was done with mausezahn on the TX side with 64 byte raw
ethernet frames.

Signed-off-by: Matteo Croce <mcroce@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 14:11:47 -07:00
Documentation dt-bindings: net: dsa: sja1105: convert to YAML schema 2021-06-07 12:20:18 -07:00
LICENSES LICENSES: Add the CC-BY-4.0 license 2020-12-08 10:33:27 -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 Kbuild updates for v5.13 (2nd) 2021-05-08 10:00:11 -07:00
crypto for-5.13/drivers-2021-04-27 2021-04-28 14:39:37 -07:00
drivers mvneta: recycle buffers 2021-06-07 14:11:47 -07:00
fs proc: Check /proc/$pid/attr/ writes against file opener 2021-05-25 10:24:41 -10:00
include page_pool: Allow drivers to hint on SKB recycling 2021-06-07 14:11:47 -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
mm userfaultfd: hugetlbfs: fix new flag usage in error path 2021-05-22 15:09:07 -10:00
net page_pool: Allow drivers to hint on SKB recycling 2021-06-07 14:11:47 -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 Merge ra.kernel.org:/pub/scm/linux/kernel/git/netdev/net 2021-06-07 13:01:52 -07:00
usr .gitignore: prefix local generated files with a slash 2021-05-02 00:43:35 +09:00
virt kvm: Cap halt polling at kvm->max_halt_poll_ns 2021-05-07 06:06:22 -04:00
.clang-format cxl for 5.12 2021-02-24 09:38:36 -08:00
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap Merge drm/drm-fixes into drm-misc-fixes 2021-05-11 13:35:52 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: move Murali Karicheri to credits 2021-04-29 15:47:30 -07:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Merge ra.kernel.org:/pub/scm/linux/kernel/git/netdev/net 2021-06-07 13:01:52 -07:00
Makefile Linux 5.13-rc3 2021-05-23 11:42:48 -10:00
README

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.