zap: reuse zap_leaf_t on dbuf reuse after shrink #16204
Merged
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Motivation and Context
Closes #16157.
Description
If a shrink or truncate had recently freed a portion of the ZAP, the dbuf could still be sitting on the dbuf cache waiting for eviction. If it is then allocated for a new leaf before it can be evicted, the
zap_leaf_t
is still attached as userdata, tripping the VERIFY.Instead, just check for the userdata, and if we find it, reuse it.
How Has This Been Tested?
zap_shrink
andvdev_zaps
(the only two "very obviously ZAPs" test tags) both passed locally.Types of changes
Checklist:
Signed-off-by
.