We're dropping the periph lock then dropping the refcount. However,
that violates the locking protocol and is racy. This seems to be
the cause of weird occasional panics with a bogus assert.
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Details
Details
- Reviewers
mav - Commits
- rS334166: We can't release the refcount outside of the periph lock.
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Diff Detail
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Buildable 16762 Build 16649: arc lint + arc unit
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Looks good to me. The only rough edge I see is that outstanding_cmds is used only for the newly added assertion, that is why it was so broken before this and nobody cared.
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Running fine for me. Reduced amount of panics, it looks like. Haven't run it for very long though.
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Yes. I think ada has similar issue with its oustanding_cmds. It's where I got it from :)
However, you're right: this is pure bug detection code. I thought about putting something like
#ifdef INVARIANTS
#define I(x) x
#else
#define I(x)
#endif
then adding I( ) around this stuff, but I decided against that for the moment...
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I've been running this patch since Tuseday evening without any issues. Without it I get a panic almost immediately when my disk is read, sometimes even before hitting multi user. Is it possible to get it committed, or what is the holdup?
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As I have told, I have no objections. I still don't like the global counters, since they mean we can never remove respective lock or at least atomics, but for now I can live with that. It is better then broken code.