Remove all instances of functions being reimplemented in the SPL.
When the prototypes are available in the linux headers but the
function address itself is not exported use kallsyms_lookup_name()
to find the address. The function name itself can them become a
define which calls a function pointer. This is preferable to
reimplementing the function in the SPL because it ensures we get
the correct version of the function for the running kernel. This
is actually pretty safe because the prototype is defined in the
headers so we know we are calling the function properly.
This patch also includes a rhel5 kernel patch we exports the needed
symbols so we don't need to use kallsyms_lookup_name(). There are
autoconf checks to detect if the symbol is exported and if so to
use it directly. We should add patches for stock upstream kernels
as needed if for no other reason than so we can easily track which
additional symbols we needed exported. Those patches can also be
used by anyone willing to rebuild their kernel, but this should
not be a requirement. The rhel5 version of the export-symbols
patch has been applied to the chaos kernel.
Additional fixes:
1) Implement vmem_size() function using get_vmalloc_info()
2) SPL_CHECK_SYMBOL_EXPORT macro updated to use $LINUX_OBJ instead
of $LINUX because Module.symvers is a build product. When
$LINUX_OBJ != $LINUX we will not properly detect exported symbols.
3) SPL_LINUX_COMPILE_IFELSE macro updated to add include2 and
$LINUX/include search paths to allow proper compilation when
the kernel target build directory is not the source directory.
Added support for Solaris swapfs_minfree, and swapfs_reserve tunables.
In additional availrmem is now available and return a reasonable value
which is reasonably analogous to the Solaris meaning. On linux we
return the sun of free and inactive pages since these are all easily
reclaimable.
All tunables are available in /proc/sys/kernel/spl/vm/* and they may
need a little adjusting once we observe the real behavior. Some of
the defaults are mapped to similar linux counterparts, others are
straight from the OpenSolaris defaults.
Support added to provide reasonable values for the global Solaris
VM variables: minfree, desfree, lotsfree, needfree. These values
are set to the sum of their per-zone linux counterparts which
should be close enough for Solaris consumers.
When a non-GPL app links against the SPL we cannot use the udev
interfaces, which means non of the device special files are created.
Because of this I had added a poor mans udev which cause the SPL
to invoke an upcall and create the basic devices when a minor
is registered. When a minor is unregistered we use the vnode
interface to unlink the special file.
- Added SPL_AC_3ARGS_ON_EACH_CPU configure check to determine
if the older 4 argument version of on_each_cpu() should be
used or the new 3 argument version. The retry argument was
dropped in the new API which was never used anyway.
- Updated work queue compatibility wrappers. The old way this
worked was to pass a data point when initialized the workqueue.
The new API assumed the work item is embedding in a structure
and we us container_of() to find that data pointer.
- Updated skc->skc_flags to be an unsigned long which is now
type checked in the bit operations. This silences the warnings.
- Updated autogen products and splat tests accordingly
of the kernel specific build info in to config/kernel,
likewise and user specific build flags should go in
config/user. This seems like a reasonable way to go.
* configure.ac : Use AC_CONFIG_AUX_DIR to put autoconf products
in ./auotconf.
* autogen.sh : Use --copy to avoid symlinks, remove error
redirection, run aclocal before libtoolize.
git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@180 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c
