github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-06-08 22:52:35 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph
Linux kernel source tree
797,976 Commits 1 Branch 934 Tags 20 GiB
C 97%
Assembly 1%
Shell 0.6%
Rust 0.5%
Python 0.4%
Other 0.3%
79b73b9f81
Go to file
Ilya Ponetayev 79b73b9f81 sch_cake: don't try to reallocate or unshare skb unconditionally 
[ Upstream commit 9208d2863a ]

cake_handle_diffserv() tries to linearize mac and network header parts of
skb and to make it writable unconditionally. In some cases it leads to full
skb reallocation, which reduces throughput and increases CPU load. Some
measurements of IPv4 forward + NAPT on MIPS router with 580 MHz single-core
CPU was conducted. It appears that on kernel 4.9 skb_try_make_writable()
reallocates skb, if skb was allocated in ethernet driver via so-called
'build skb' method from page cache (it was discovered by strange increase
of kmalloc-2048 slab at first).

Obtain DSCP value via read-only skb_header_pointer() call, and leave
linearization only for DSCP bleaching or ECN CE setting. And, as an
additional optimisation, skip diffserv parsing entirely if it is not needed
by the current configuration.

Fixes: c87b4ecdbe ("sch_cake: Make sure we can write the IP header before changing DSCP bits")
Signed-off-by: Ilya Ponetayev <i.ponetaev@ndmsystems.com>
[ fix a few style issues, reflow commit message ]
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-30 23:17:06 -04:00
arch fix a braino in "sparc32: fix register window handling in genregs32_[gs]et()" 2020-06-30 23:17:02 -04:00
block block/bio-integrity: don't free 'buf' if bio_integrity_add_page() failed 2020-06-30 23:17:00 -04:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto crypto: algboss - don't wait during notifier callback 2020-06-25 15:33:09 +02:00
Documentation mtd: rawnand: Pass a nand_chip object to nand_release() 2020-06-25 15:33:08 +02:00
drivers net: phy: Check harder for errors in get_phy_id() 2020-06-30 23:17:06 -04:00
firmware Fix built-in early-load Intel microcode alignment 2020-01-23 08:21:29 +01:00
fs fanotify: fix ignore mask logic for events on child and on dir 2020-06-30 23:17:00 -04:00
include sctp: Don't advertise IPv4 addresses if ipv6only is set on the socket 2020-06-30 23:17:05 -04:00
init x86: Fix early boot crash on gcc-10, third try 2020-05-20 08:18:49 +02:00
ipc ipc/util.c: sysvipc_find_ipc() incorrectly updates position index 2020-05-20 08:18:40 +02:00
kernel kretprobe: Prevent triggering kretprobe from within kprobe_flush_task 2020-06-25 15:33:10 +02:00
lib lib/zlib: remove outdated and incorrect pre-increment optimization 2020-06-25 15:33:02 +02:00
LICENSES LICENSES: Remove CC-BY-SA-4.0 license text 2018-10-18 11:28:50 +02:00
mm mm: initialize deferred pages with interrupts enabled 2020-06-22 09:05:21 +02:00
net sch_cake: don't try to reallocate or unshare skb unconditionally 2020-06-30 23:17:06 -04:00
samples samples: bpf: Fix build error 2020-06-03 08:19:31 +02:00
scripts mksysmap: Fix the mismatch of '.L' symbols in System.map 2020-06-25 15:32:51 +02:00
security apparmor: don't try to replace stale label in ptraceme check 2020-06-30 23:17:03 -04:00
sound ALSA: hda/realtek - Enable micmute LED on and HP system 2020-06-30 23:17:03 -04:00
tools perf report: Fix NULL pointer dereference in hists__fprintf_nr_sample_events() 2020-06-25 15:33:05 +02:00
usr initramfs: restore default compression behavior 2020-04-13 10:44:59 +02:00
virt KVM: arm64: Synchronize sysreg state on injecting an AArch32 exception 2020-06-22 09:05:09 +02:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS MAINTAINERS: Update drm/i915 bug filing URL 2020-02-28 16:38:49 +01:00
Makefile Linux 4.19.130 2020-06-25 15:33:11 +02:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

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.
See Documentation/00-INDEX for a list of what is contained in each file.

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.