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.
Jakub Kicinski
authored
Jakub Kicinski says: ==================== page_pool: allow caching from safely localized NAPI I went back to the explicit "are we in NAPI method", mostly because I don't like having both around :( (even tho I maintain that in_softirq() && !in_hardirq() is as safe, as softirqs do not nest). Still returning the skbs to a CPU, tho, not to the NAPI instance. I reckon we could create a small refcounted struct per NAPI instance which would allow sockets and other users so hold a persisent and safe reference. But that's a bigger change, and I get 90+% recycling thru the cache with just these patches (for RR and streaming tests with 100% CPU use it's almost 100%). Some numbers for streaming test with 100% CPU use (from previous version, but really they perform the same): HW-GRO page=page before after before after recycle: cached: 0 138669686 0 150197505 cache_full: 0 223391 0 74582 ring: 138551933 9997191 149299454 0 ring_full: 0 488 3154 127590 released_refcnt: 0 0 0 0 alloc: fast: 136491361 148615710 146969587 150322859 slow: 1772 1799 144 105 slow_high_order: 0 0 0 0 empty: 1772 1799 144 105 refill: 2165245 156302 2332880 2128 waive: 0 0 0 0 v1: https://lore.kernel.org/all/20230411201800.596103-1-kuba@kernel.org/ rfcv2: https://lore.kernel.org/all/20230405232100.103392-1-kuba@kernel.org/ ==================== Link: https://lore.kernel.org/r/20230413042605.895677-1-kuba@kernel.org Signed-off-by:Jakub Kicinski <kuba@kernel.org>