d6bd8eaae4
Now that KM_SLEEP is not defined as GFP_NOFS there is the possibility of synchronous reclaim deadlocks. These deadlocks never existed in the original OpenSolaris code because all memory reclaim on Solaris is done asyncronously. Linux does both synchronous (direct) and asynchronous (indirect) reclaim. This commit addresses a deadlock caused by inode eviction. A KM_SLEEP allocation may trigger direct memory reclaim and shrink the inode cache. This can occur while a mutex in the array of ZFS_OBJ_HOLD mutexes is held. Through the ->shrink_icache_memory()->evict()->zfs_inactive()-> zfs_zinactive() call path the same mutex may be reacquired resulting in a deadlock. To avoid this deadlock the process must not reacquire the mutex when it is already holding it. This is a reasonable fix for now but longer term the ZFS_OBJ_HOLD mutex locking should be reevaluated. This infrastructure already prevents us from ever using the Linux lock dependency analysis tools, and it may limit scalability. |
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.. | ||
linux | ||
sys | ||
Makefile.am | ||
Makefile.in | ||
libnvpair.h | ||
libuutil.h | ||
libuutil_common.h | ||
libuutil_impl.h | ||
libzfs.h | ||
libzfs_impl.h | ||
zfs_comutil.h | ||
zfs_deleg.h | ||
zfs_fletcher.h | ||
zfs_namecheck.h | ||
zfs_prop.h | ||
zpios-ctl.h | ||
zpios-internal.h |