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a315b723e8
Completion queues (CQs) in mlx5 use the same global doorbell, which may become contended when accessed concurrently from many cores. This patch prepares the CQ management code for supporting different doorbells per CQ. This will be used in downstream patches to allow separate doorbells to be used by channels CQs. The main change is moving the 'uar' pointer from struct mlx5_core_cq to struct mlx5e_cq, as the uar page to be used is better off stored directly there. Other users of mlx5_core_cq also store the UAR to be used separately and therefore the pointer being removed is dead weight for them. As evidence, in this patch there are two users which set the mcq.uar pointer but didn't use it, Software Steering and old Innova CQ creation code. Instead, they rang the doorbell directly from another pointer. The 'uar' pointer added to struct mlx5e_cq remains in a hot cacheline (as before), because it may get accessed for each packet. Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com> Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com> Signed-off-by: Tariq Toukan <tariqt@nvidia.com> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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 reStructuredText 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.