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Jacob Keller
649c87c6ff
Several headers in the ice driver include ice.h even though they are themselves included by that header. The most notable of these is ice_common.h, but several other headers also do this. Such a recursive inclusion is problematic as it forces headers to be included in a strict order, otherwise compilation errors can result. The circular inclusions do not trigger an endless loop due to standard header inclusion guards, however other errors can occur. For example, ice_flow.h defines ice_rss_hash_cfg, which is used by ice_sriov.h as part of the definition of ice_vf_hash_ip_ctx. ice_flow.h includes ice_acl.h, which includes ice_common.h, and which finally includes ice.h. Since ice.h itself includes ice_sriov.h, this creates a circular dependency. The definition in ice_sriov.h requires things from ice_flow.h, but ice_flow.h itself will lead to trying to load ice_sriov.h as part of its process for expanding ice.h. The current code avoids this issue by having an implicit dependency without the include of ice_flow.h. If we were to fix that so that ice_sriov.h explicitly depends on ice_flow.h the following pattern would occur: ice_flow.h -> ice_acl.h -> ice_common.h -> ice.h -> ice_sriov.h At this point, during the expansion of, the header guard for ice_flow.h is already set, so when ice_sriov.h attempts to load the ice_flow.h header it is skipped. Then, we go on to begin including the rest of ice_sriov.h, including structure definitions which depend on ice_rss_hash_cfg. This produces a compiler warning because ice_rss_hash_cfg hasn't yet been included. Remember, we're just at the start of ice_flow.h! If the order of headers is incorrect (ice_flow.h is not implicitly loaded first in all files which include ice_sriov.h) then we get the same failure. Removing this recursive inclusion requires fixing a few cases where some headers depended on the header inclusions from ice.h. In addition, a few other changes are also required. Most notably, ice_hw_to_dev is implemented as a macro in ice_osdep.h, which is the likely reason that ice_common.h includes ice.h at all. This macro implementation requires the full definition of ice_pf in order to properly compile. Fix this by moving it to a function declared in ice_main.c, so that we do not require all files to depend on the layout of the ice_pf structure. Note that this change only fixes circular dependencies, but it does not fully resolve all implicit dependencies where one header may depend on the inclusion of another. I tried to fix as many of the implicit dependencies as I noticed, but fixing them all requires a somewhat tedious analysis of each header and attempting to compile it separately. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Tested-by: Gurucharan G <gurucharanx.g@intel.com> (A Contingent worker at Intel) Signed-off-by: Tony Nguyen <anthony.l.nguyen@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.