vm_object: Remove redundant OBJ_SWAP checks
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Authored by markj on Jul 12 2022, 4:23 PM.

Details

Reviewers

dougm
alc
kib

Commits

rGfff19e0ed2f3: vm_object: Remove redundant OBJ_SWAP checks

Summary

With the removal of OBJT_DEFAULT, OBJ_ANON implies OBJ_SWAP.

Note, this means that vm_object_split() is more expensive than it used
to be, as it holds busy locks until the end of the range is reached,
even if the object has no swap blocks allocated. I am still not sure
why exactly we need to do this even when swap blocks are allocated.

Diff Detail

Repository

rG FreeBSD src repository

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Event Timeline

markj created this revision.Jul 12 2022, 4:23 PM

Herald added a subscriber: imp. · View Herald TranscriptJul 12 2022, 4:23 PM

markj requested review of this revision.Jul 12 2022, 4:23 PM

Harbormaster completed remote builds in B46386: Diff 108061.Jul 12 2022, 4:23 PM

markj added a parent revision: D35788: vm: Remove handling for OBJT_DEFAULT objects.Jul 12 2022, 4:23 PM

markj added a child revision: D35790: vm_pager: Remove the default pager.

kib accepted this revision.Jul 12 2022, 6:05 PM

This revision is now accepted and ready to land.Jul 12 2022, 6:05 PM

alc added inline comments.Jul 13 2022, 8:09 AM

sys/vm/vm_object.c
1525–1526	Now stale comment.

markj marked an inline comment as done.Jul 13 2022, 1:25 PM

markj added inline comments.

sys/vm/vm_object.c
1525–1526	I'll fix this in D35788 as that's where most of the similar cleanup happens.

alc accepted this revision.Jul 13 2022, 3:32 PM

alc added inline comments.

sys/vm/vm_object.c
1961–1962	Doug, after Mark's commits land, could you change swp_pager_meta_transfer() so that it returns immediately at the start if the source trie is empty.