NAPI poll can be done in threaded context along with soft irq context. Threaded context can be scheduled efficiently, thus creating less of bottleneck during Rx processing. This patch is to enable threaded NAPI on ath10k driver. Based on testing, it was observed that on WCN3990, the CPU0 reaches 100% utilization when napi runs in softirq context. At the same time the other CPUs are at low consumption percentage. This does not allow device to reach its maximum throughput potential. After enabling threaded napi, CPU load is balanced across all CPUs and following improvments were observed: - UDP_RX increase by ~22-25% - TCP_RX increase by ~15% Here are some of the additional raw data with and without threaded napi: ================================================== udp_rx(Without threaded NAPI) 435.98+-5.16 : Channel 44 439.06+-0.66 : Channel 157 udp_rx(With threaded NAPI) 509.73+-41.03 : Channel 44 549.97+-7.62 : Channel 157 =================================================== udp_tx(Without threaded NAPI) 461.31+-0.69 : Channel 44 461.46+-0.78 : Channel 157 udp_tx(With threaded NAPI) 459.20+-0.77 : Channel 44 459.78+-1.08 : Channel 157 =================================================== tcp_rx(Without threaded NAPI) 472.63+-2.35 : Channel 44 469.29+-6.31 : Channel 157 tcp_rx(With threaded NAPI) 498.49+-2.44 : Channel 44 541.14+-40.65 : Channel 157 =================================================== tcp_tx(Without threaded NAPI) 317.34+-2.37 : Channel 44 317.01+-2.56 : Channel 157 tcp_tx(With threaded NAPI) 371.34+-2.36 : Channel 44 376.95+-9.40 : Channel 157 =================================================== Tested-on: WCN3990 hw1.0 SNOC WLAN.HL.3.2.2-00696-QCAHLSWMTPL-1 Signed-off-by: Abhishek Kumar <kuabhs@chromium.org> Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com> Link: https://lore.kernel.org/r/20230203000116.v2.1.I5bb9c164a2d2025655dee810b983e01ecd81c14e@changeid
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
97.6%
Assembly
1%
Shell
0.5%
Python
0.3%
Makefile
0.3%