Brian Behlendorf 9631681b75 Fix dnode allocation race ... When performing concurrent object allocations using the new multi-threaded allocator and large dnodes it's possible to allocate overlapping large dnodes. This case should have been handled by detecting an error returned by dnode_hold_impl(). But that logic only checked the returned dnp was not-NULL, and the dnp variable was not reset to NULL when retrying. Resolve this issue by properly checking the return value of dnode_hold_impl(). Additionally, it was possible that dnode_hold_impl() would misreport a dnode as free when it was in fact in use. This could occurs for two reasons: * The per-slot zrl_lock must be held over the entire critical section which includes the alloc/free until the new dnode is assigned to children_dnodes. Additionally, all of the zrl_lock's in the range must be held to protect moving dnodes. * The dn->dn_ot_type cannot be solely relied upon to check the type. When allocating a new dnode its type will be DMU_OT_NONE after dnode_create(). Only latter when dnode_allocate() is called will it transition to the new type. This means there's a window when allocating where it can mistaken for a free dnode. Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov> Reviewed-by: Ned Bass <bass6@llnl.gov> Reviewed-by: Tony Hutter <hutter2@llnl.gov> Reviewed-by: Olaf Faaland <faaland1@llnl.gov> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Closes #6414 Closes #6439		2017-08-08 08:38:53 -07:00
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linux.run	Fix dnode allocation race	2017-08-08 08:38:53 -07:00
Makefile.am	Add the ZFS Test Suite	2016-03-16 13:46:16 -07:00
perf-regression.run	OpenZFS - Performance regression suite for zfstest	2016-09-08 16:18:28 -07:00