Sven Van Asbroeck efc570073c lan743x: fix rx_napi_poll/interrupt ping-pong ... [ Upstream commit 57030a0b62 ] Even if there is more rx data waiting on the chip, the rx napi poll fn will never run more than once - it will always read a few buffers, then bail out and re-arm interrupts. Which results in ping-pong between napi and interrupt. This defeats the purpose of napi, and is bad for performance. Fix by making the rx napi poll behave identically to other ethernet drivers: 1. initialize rx napi polling with an arbitrary budget (64). 2. in the polling fn, return full weight if rx queue is not depleted, this tells the napi core to "keep polling". 3. update the rx tail ("ring the doorbell") once for every 8 processed rx ring buffers. Thanks to Jakub Kicinski, Eric Dumazet and Andrew Lunn for their expert opinions and suggestions. Tested with 20 seconds of full bandwidth receive (iperf3): rx irqs softirqs(NET_RX) ----------------------------- before 23827 33620 after 129 4081 Tested-by: Sven Van Asbroeck <thesven73@gmail.com> # lan7430 Fixes: 23f0703c12 ("lan743x: Add main source files for new lan743x driver") Signed-off-by: Sven Van Asbroeck <thesven73@gmail.com> Link: https://lore.kernel.org/r/20201215161954.5950-1-TheSven73@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2020-12-30 11:51:27 +01:00
..
Kconfig	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
Makefile	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
enc28j60.c	enc28j60: Convert to use SPDX identifier	2019-03-19 14:59:32 -07:00
enc28j60_hw.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
encx24j600-regmap.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500	2019-06-19 17:09:55 +02:00
encx24j600.c	net: microchip: encx24j600: add missed kthread_stop	2020-06-03 08:21:09 +02:00
encx24j600_hw.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
lan743x_ethtool.c	lan743x: fix for potential NULL pointer dereference with bare card	2020-12-21 13:27:04 +01:00
lan743x_ethtool.h	lan743x: Add support for ethtool get_drvinfo	2018-07-23 14:09:18 -07:00
lan743x_main.c	lan743x: fix rx_napi_poll/interrupt ping-pong	2020-12-30 11:51:27 +01:00
lan743x_main.h	lan743x: fix "BUG: invalid wait context" when setting rx mode	2020-11-18 19:20:27 +01:00
lan743x_ptp.c	net: reject PTP periodic output requests with unsupported flags	2019-11-15 12:48:32 -08:00
lan743x_ptp.h	net: lan743x: fix building without CONFIG_PTP_1588_CLOCK	2018-08-13 20:43:47 -07:00