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5672225e8f
Commitdc04db2aa7has caused a small aim7 regression, showing a small increase in CPU usage in __xfs_btree_check_sblock() as a result of the extra checking. This is likely due to the endian conversion of the sibling poitners being unconditional instead of relying on the compiler to endian convert the NULL pointer at compile time and avoiding the runtime conversion for this common case. Rework the checks so that endian conversion of the sibling pointers is only done if they are not null as the original code did. .... and these need to be "inline" because the compiler completely fails to inline them automatically like it should be doing. $ size fs/xfs/libxfs/xfs_btree.o* text data bss dec hex filename 51874 240 0 52114 cb92 fs/xfs/libxfs/xfs_btree.o.orig 51562 240 0 51802 ca5a fs/xfs/libxfs/xfs_btree.o.inline Just when you think the tools have advanced sufficiently we don't have to care about stuff like this anymore, along comes a reminder that *our tools still suck*. Fixes:dc04db2aa7("xfs: detect self referencing btree sibling pointers") Reported-by: kernel test robot <oliver.sang@intel.com> Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.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.