mirror of
https://github.com/hardkernel/linux.git
synced 2026-06-10 04:48:04 +09:00
bd07a20a38b6598dc09f5543eb03710e807cb429
Polling by MSI isn't necessarily faster than polling by SEV. Tests on hi1620 show hns3 100G NIC network throughput can improve from 25G to 27G if we disable MSI polling while running 16 netperf threads sending UDP packets in size 32KB. TX throughput can improve from 7G to 7.7G for single thread. The reason for the throughput improvement is that the latency to poll the completion of CMD_SYNC becomes smaller. After sending a CMD_SYNC in an empty cmd queue, typically we need to wait for 280ns using MSI polling. But we only need around 190ns after disabling MSI polling. This patch provides a command line option so that users can decide to use MSI polling or not based on their tests. Signed-off-by: Barry Song <song.bao.hua@hisilicon.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Link: https://lore.kernel.org/r/20200827092957.22500-4-song.bao.hua@hisilicon.com Signed-off-by: Will Deacon <will@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 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.
Description
Languages
C
97.7%
Assembly
1.6%
Makefile
0.3%
Perl
0.1%