mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2026-09-22 09:34:56 +02:00
Jakub Kicinski
4d1d3b52dc
Yunsheng Lin says:
====================
Replace page_frag with page_frag_cache (Part-1)
This is part 1 of "Replace page_frag with page_frag_cache",
which mainly contain refactoring and optimization for the
implementation of page_frag API before the replacing.
As the discussion in [1], it would be better to target net-next
tree to get more testing as all the callers page_frag API are
in networking, and the chance of conflicting with MM tree seems
low as implementation of page_frag API seems quite self-contained.
After [2], there are still two implementations for page frag:
1. mm/page_alloc.c: net stack seems to be using it in the
rx part with 'struct page_frag_cache' and the main API
being page_frag_alloc_align().
2. net/core/sock.c: net stack seems to be using it in the
tx part with 'struct page_frag' and the main API being
skb_page_frag_refill().
This patchset tries to unfiy the page frag implementation
by replacing page_frag with page_frag_cache for sk_page_frag()
first. net_high_order_alloc_disable_key for the implementation
in net/core/sock.c doesn't seems matter that much now as pcp
is also supported for high-order pages:
commit 44042b4498 ("mm/page_alloc: allow high-order pages to
be stored on the per-cpu lists")
As the related change is mostly related to networking, so
targeting the net-next. And will try to replace the rest
of page_frag in the follow patchset.
After this patchset:
1. Unify the page frag implementation by taking the best out of
two the existing implementations: we are able to save some space
for the 'page_frag_cache' API user, and avoid 'get_page()' for
the old 'page_frag' API user.
2. Future bugfix and performance can be done in one place, hence
improving maintainability of page_frag's implementation.
Kernel Image changing:
Linux Kernel total | text data bss
------------------------------------------------------
after 45250307 | 27274279 17209996 766032
before 45254134 | 27278118 17209984 766032
delta -3827 | -3839 +12 +0
1. https://lore.kernel.org/all/add10dd4-7f5d-4aa1-aa04-767590f944e0@redhat.com/
2. https://lore.kernel.org/all/20240228093013.8263-1-linyunsheng@huawei.com/
====================
Link: https://patch.msgid.link/20241028115343.3405838-1-linyunsheng@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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 reStructuredText 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.