aboutsummaryrefslogtreecommitdiffstats
path: root/patches
Commit message (Collapse)AuthorAgeFilesLines
* Reimplement rwlocks for Linux lock profiling/analysis.Brian Behlendorf2009-09-181-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It turns out that the previous rwlock implementation worked well but did not integrate properly with the upstream kernel lock profiling/ analysis tools. This is a major problem since it would be awfully nice to be able to use the automatic lock checker and profiler. The problem is that the upstream lock tools use the pre-processor to create a lock class for each uniquely named locked. Since the rwsem was embedded in a wrapper structure the name was always the same. The effect was that we only ended up with one lock class for the entire SPL which caused the lock dependency checker to flag nearly everything as a possible deadlock. The solution was to directly map a krwlock to a Linux rwsem using a typedef there by eliminating the wrapper structure. This was not done initially because the rwsem implementation is specific to the arch. To fully implement the Solaris krwlock API using only the provided rwsem API is not possible. It can only be done by directly accessing some of the internal data member of the rwsem structure. For example, the Linux API provides a different function for dropping a reader vs writer lock. Whereas the Solaris API uses the same function and the caller does not pass in what type of lock it is. This means to properly drop the lock we need to determine if the lock is currently a reader or writer lock. Then we need to call the proper Linux API function. Unfortunately, there is no provided API for this so we must extracted this information directly from arch specific lock implementation. This is all do able, and what I did, but it does complicate things considerably. The good news is that in addition to the profiling benefits of this change. We may see performance improvements due to slightly reduced overhead when creating rwlocks and manipulating them. The only function I was forced to sacrafice was rw_owner() because this information is simply not stored anywhere in the rwsem. Luckily this appears not to be a commonly used function on Solaris, and it is my understanding it is mainly used for debugging anyway. In addition to the core rwlock changes, extensive updates were made to the rwlock regression tests. Each class of test was extended to provide more API coverage and to be more rigerous in checking for misbehavior. This is a pretty significant change and with that in mind I have been careful to validate it on several platforms before committing. The full SPLAT regression test suite was run numberous times on all of the following platforms. This includes various kernels ranging from 2.6.16 to 2.6.29. - SLES10 (ppc64) - SLES11 (x86_64) - CHAOS4.2 (x86_64) - RHEL5.3 (x86_64) - RHEL6 (x86_64) - FC11 (x86_64)
* Required missing symbols for FC11 kernels (2.6.29.4-167.fc11.x86_64)Brian Behlendorf2009-07-311-0/+94
|
* Linux VM Integration CleanupBrian Behlendorf2009-03-043-25/+91
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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.
* Add the minimal set of kernel patches need to for the SPL. Hopefullybehlendo2008-06-022-0/+25
even these will not be needed over the next few weeks. git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@121 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c