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Jonathan Brassow authored
A clear_region function is permitted to block (in practice, rare) but gets called in rh_update_states() with a spinlock held. The bits being marked and cleared by the above functions are used to update the on-disk log, but are never read directly. We can perform these operations outside the spinlock since the bits are only changed within one thread viz. - mark_region in rh_inc() - clear_region in rh_update_states(). So, we grab the clean_regions list items via list_splice() within the spinlock and defer clear_region() until we iterate over the list for deletion - similar to how the recovered_regions list is already handled. We then move the flush() call down to ensure it encapsulates the changes which are done by the later calls to clear_region(). Signed-off-by:
Jonathan Brassow <jbrassow@redhat.com> Signed-off-by:
Alasdair G Kergon <agk@redhat.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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