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3f0d97cdfe
If a UMEM is present on a queue when an interface/queue pair is being
enabled, the driver will try to prepare the Rx buffers in advance to
improve performance. However, if fill queue is shorter than HW Rx ring,
the driver will report failure after getting the last address from the
fill queue.
This still lets the driver process the packets correctly during the NAPI
poll, but leads to a constant NAPI rescheduling. Not allocating the
buffers in advance would result in a potential performance decrease.
Commit d57d76428a ("xsk: Add API to check for available entries in FQ")
provides an API that lets drivers check the number of addresses that the
fill queue holds.
Notify the user if fill queue is not long enough to prepare all buffers
before packet processing starts, and allocate the buffers during the
NAPI poll. If the fill queue size is sufficient, prepare Rx buffers in
advance.
Signed-off-by: Krzysztof Kazimierczak <krzysztof.kazimierczak@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
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.