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cam: remove sim callout
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Authored by imp on May 21 2021, 3:22 PM.

Details

Reviewers
scottl
ken
mav
Group Reviewers
cam
Commits
rG28027f28e607: cam: remove sim callout
Summary

Nothing is using the sim callout to unfreeze the queue. Remove it to
simplify the SIM.

Sponsored by: Netflix

Diff Detail

Repository
rG FreeBSD src repository
Lint
Automatic diff as part of commit; lint not applicable.
Unit
Automatic diff as part of commit; unit tests not applicable.

Event Timeline

imp requested review of this revision.May 21 2021, 3:22 PM
imp added inline comments.
sys/cam/cam_sim.h
104–105

I know flags is now unused after this change, but I'm about to use it for other reasons which
is why I noticed this feature was unused.

sys/cam/cam_sim.h
105

This was introduced by Justin in the initial CAM commit. It was used to freeze the queue on a bus reset. Now we just note the time of the reset. It's not been set in the CAM code since sometime before stable/3 (the oldest tree I have around). It looks like it was removed in 1999 when Justin re-did the bug reset logic. 6d039cdb75977fabc63ee268a96c990f08ea68ed has the MFC to stable/3, though I've not trolled to see where it changed on main yet given how old it is.

R10:87cfaf0e1fbd38cf7f9843ec462b5401e914f4d1 is the commit in main that removed setting this flag.

Also, the free code doesn't cancel the callout and there's no locking around it at all to keep multiple threads from frobbing it.

This revision is now accepted and ready to land.May 21 2021, 7:30 PM
This revision was automatically updated to reflect the committed changes.