Brian Behlendorf 043f9b5724 Disable FS reclaim when allocating new slabs ... Allowing the spl_cache_grow_work() function to reclaim inodes allows for two unlikely deadlocks. Therefore, we clear __GFP_FS for these allocations. The two deadlocks are: * While holding the ZFS_OBJ_HOLD_ENTER(zsb, obj1) lock a function calls kmem_cache_alloc() which happens to need to allocate a new slab. To allocate the new slab we enter FS level reclaim and attempt to evict several inodes. To evict these inodes we need to take the ZFS_OBJ_HOLD_ENTER(zsb, obj2) lock and it just happens that obj1 and obj2 use the same hashed lock. * Similar to the first case however instead of getting blocked on the hash lock we block in txg_wait_open() which is waiting for the next txg which isn't coming because the txg_sync thread is blocked in kmem_cache_alloc(). Note this isn't a 100% fix because vmalloc() won't strictly honor __GFP_FS. However, it practice this is sufficient because several very unlikely things must all occur concurrently. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue zfsonlinux/zfs#1101		2012-11-27 13:43:27 -08:00
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spl	Disable FS reclaim when allocating new slabs	2012-11-27 13:43:27 -08:00
splat	splat kmem:slab_overcommit: Disabled	2012-11-06 14:48:57 -08:00
.gitignore	Remove Makefile from non-toplevel .gitignore files	2012-08-23 12:49:04 -07:00
Makefile.in	Add script for builtin module building.	2012-07-26 15:13:09 -07:00