43da44c876
Jose Abreu says: ==================== net: stmmac: CPU Performance Improvements CPU Performance improvements for stmmac. Please check bellow for results before and after the series. Patch 1/7, allows RX Interrupt on Completion to be disabled and only use the RX HW Watchdog. Patch 2/7, setups the default RX coalesce settings instead of using the minimum value. Patch 3/7 and 4/7, removes the uneeded computations for RX Flow Control activation/de-activation, on some cases. Patch 5/7, tunes-up the default coalesce settings. Patch 6/7, re-works the TX coalesce timer activation logic. Patch 7/7, removes the now uneeded TBU interrupt. NetPerf UDP Results: -------------------- Socket Message Elapsed Messages CPU Service Size Size Time Okay Errors Throughput Util Demand bytes bytes secs # # 10^6bits/sec % SS us/KB --- XGMAC@2.5G: Before 212992 1400 10.00 2100620 0 2351.7 36.69 5.112 212992 10.00 2100539 2351.6 26.18 3.648 --- XGMAC@2.5G: After 212992 1400 10.00 2108972 0 2361.5 21.73 3.015 212992 10.00 2097038 2348.1 19.21 2.666 --- GMAC5@1G: Before 212992 1400 10.00 786000 0 880.2 34.71 12.923 212992 10.00 786000 880.2 23.42 8.719 --- GMAC5@1G: After 212992 1400 10.00 842648 0 943.7 14.12 4.903 212992 10.00 842648 943.7 12.73 4.418 Perf TCP Results on RX Path: ---------------------------- --- XGMAC@2.5G: Before 22.51% swapper [stmmac] [k] dwxgmac2_dma_interrupt 10.82% swapper [stmmac] [k] dwxgmac2_host_mtl_irq_status 5.21% swapper [stmmac] [k] dwxgmac2_host_irq_status 4.67% swapper [stmmac] [k] dwxgmac3_safety_feat_irq_status 3.63% swapper [kernel.kallsyms] [k] stack_trace_consume_entry 2.74% iperf3 [kernel.kallsyms] [k] copy_user_enhanced_fast_string 2.52% swapper [kernel.kallsyms] [k] update_stack_state 1.94% ksoftirqd/0 [stmmac] [k] dwxgmac2_dma_interrupt 1.45% iperf3 [kernel.kallsyms] [k] queued_spin_lock_slowpath 1.26% swapper [kernel.kallsyms] [k] create_object --- XGMAC@2.5G: After 7.43% swapper [kernel.kallsyms] [k] stack_trace_consume_entry 5.86% swapper [stmmac] [k] dwxgmac2_dma_interrupt 5.68% swapper [kernel.kallsyms] [k] update_stack_state 4.71% iperf3 [kernel.kallsyms] [k] copy_user_enhanced_fast_string 2.88% swapper [kernel.kallsyms] [k] create_object 2.69% swapper [stmmac] [k] dwxgmac2_host_mtl_irq_status 2.61% swapper [stmmac] [k] stmmac_napi_poll_rx 2.52% swapper [kernel.kallsyms] [k] unwind_next_frame.part.4 1.48% swapper [kernel.kallsyms] [k] unwind_get_return_address 1.38% swapper [kernel.kallsyms] [k] arch_stack_walk --- GMAC5@1G: Before 31.29% swapper [stmmac] [k] dwmac4_dma_interrupt 14.57% swapper [stmmac] [k] dwmac4_irq_mtl_status 10.66% swapper [stmmac] [k] dwmac4_irq_status 1.97% swapper [kernel.kallsyms] [k] stack_trace_consume_entry 1.73% iperf3 [kernel.kallsyms] [k] copy_user_enhanced_fast_string 1.59% swapper [kernel.kallsyms] [k] update_stack_state 1.15% iperf3 [kernel.kallsyms] [k] do_syscall_64 1.01% ksoftirqd/0 [stmmac] [k] dwmac4_dma_interrupt 0.89% swapper [kernel.kallsyms] [k] __default_send_IPI_dest_field 0.75% swapper [stmmac] [k] stmmac_napi_poll_rx --- GMAC5@1G: After 6.70% swapper [kernel.kallsyms] [k] stack_trace_consume_entry 5.79% swapper [stmmac] [k] dwmac4_dma_interrupt 5.29% swapper [kernel.kallsyms] [k] update_stack_state 3.52% iperf3 [kernel.kallsyms] [k] copy_user_enhanced_fast_string 2.83% swapper [stmmac] [k] dwmac4_irq_mtl_status 2.62% swapper [kernel.kallsyms] [k] create_object 2.46% swapper [stmmac] [k] stmmac_napi_poll_rx 2.32% swapper [kernel.kallsyms] [k] unwind_next_frame.part.4 2.19% swapper [stmmac] [k] dwmac4_irq_status 1.39% swapper [kernel.kallsyms] [k] unwind_get_return_address ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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.