Summary:
Starvation is currently path insensitive. Two special cases of sensitivity cover a large range of useful cases:
- sensitivity on whether the current thread is a UI/background thread;
- sensitivity on whether a lock can be acquired (without blocking) or not.
We add a few tests capturing some of the false positives and negatives of the current analysis.
Reviewed By: mityal
Differential Revision: D17907492
fbshipit-source-id: fbce896ac
Summary:
The old domain keeps two sets:
- `events` are things (including lock acquisitions) which eventually happen during the execution of a procedure.
- `order` are pairs of `(lock, event)` such that there is a trace through the procedure which at some point acquires `lock` and before releasing it performs `event`.
A deadlock would be reported if for two procedures, `(lock1,lock2)` is in `order` of procedure 1 and `(lock2,lock1)` is in `order` of procedure 2. This condition/domain allowed for the false positive fixed in the tests, as well as was unwieldy, because it required translating between the two sets.
The new domain has only one set of "critical pairs" `(locks, event)` such that there is a trace where `event` occurs, and *right before it occurs* the locks held are exactly `locks` (no over/under approximation). This allows keeping all information in one set, simplifies the procedure call handling and eliminates the known false positive.
Reviewed By: mityal
Differential Revision: D17686944
fbshipit-source-id: 3c68bb957
Summary: Holding a master lock and then acquiring two other locks inside can generate a false positive as shown.
Reviewed By: mityal
Differential Revision: D17710076
fbshipit-source-id: 5bc910ba2
Summary:
Previously deduplication was always on which is not great for testing.
Also split tests so that we can still test deduplication separately.
Reviewed By: mityal
Differential Revision: D17686877
fbshipit-source-id: 280d91473
Summary:
Ideally the analyser should equate locks `this.x.f` and `a.x.f` in different methods if they can alias.
The heuristic removed here was rarely used and is in the way of a re-write of the analysis.
It was also badly implemented, as this should ideally be the comparison relation of `Lock`.
Reviewed By: mityal
Differential Revision: D17602827
fbshipit-source-id: 4f4576c1a
Summary:
Make distinct reports on strict mode violations.
For now, restrict to direct violations (UI threads calls transitively a violating method).
Will assess impact and enable indirect reports later (via locks).
Reviewed By: mbouaziz
Differential Revision: D10126780
fbshipit-source-id: 9c75930bc
Summary: Sometimes it's very confusing to see why infer believes a method is running on the UI thread. Make a trace out of all the relevant info.
Reviewed By: mbouaziz
Differential Revision: D9781212
fbshipit-source-id: 6d018e400
Summary: The `procedure` field in the final report should use the non-ambiguous fully qualified name containing the Java package declaration and the list of parameter types.
Reviewed By: mbouaziz
Differential Revision: D9237522
fbshipit-source-id: e9b0ff664
Summary: Treat calls to Thread.sleep as blocking, even when the timeouts are less than the ANR limit.
Reviewed By: da319
Differential Revision: D9027950
fbshipit-source-id: 001409896
Summary:
Guava subclasses Future in ways that make .get() calls safe from the UI thread.
Treat such methods as skip.
Reviewed By: jeremydubreil
Differential Revision: D9013475
fbshipit-source-id: 38373aa5f
Summary:
Currently, some blocking calls are turning up too many false positives. Adjust severities by fix rate/preexisting numbers.
Also, restrict some calls to exact class, as opposed to superclasses.
Reviewed By: mbouaziz
Differential Revision: D8850599
fbshipit-source-id: 47543d04a
Summary: Trying to convert a large int literal to an OCaml int raises an exception. The use case here actually needed a float anyway, so add an API for that.
Reviewed By: jeremydubreil
Differential Revision: D8550410
fbshipit-source-id: 382495b
Summary:
We need to report on non-private methods (the opposite even leads to FPs sometimes on deadlocks). To do this, the domain needs to change so that the interpretation of an order pair `a,b` is no longer "lock `a` is taken in the *current method* and held until lock `b` is taken". Instead the meaning is now "lock `a` is taken in some method *of the same class with the current method* and is held until `b` is taken".
These changes are quite drastic because the previous implementation optimised extensively around the previous use case.
Reviewed By: mbouaziz
Differential Revision: D8395351
fbshipit-source-id: a2bd22b
Summary:
The deadlock reports (the actual string) were too low level, in order to avoid bug hash clashes. Now that we deduplicate this is less of an issue, so it's an opportunity to improve readability.
```
Potential deadlock.
Trace 1 (starts at `void Interproc.interproc1Bad(InterprocA)`) first locks `this` in class `Interproc*` (line 9 in `void Interproc.interproc1Bad(InterprocA)`) and then locks `b` in class `InterprocA*` (line 14 in `void Interproc.interproc2Bad(InterprocA)`).
Trace 2 (starts at `void InterprocA.interproc1Bad(Interproc)`), first locks `this` in class `InterprocA*` (line 37 in `void InterprocA.interproc1Bad(Interproc)`) and then locks `d` in class `Interproc*` (line 42 in `void InterprocA.interproc2Bad(Interproc)`).
```
Reviewed By: mbouaziz
Differential Revision: D8394978
fbshipit-source-id: 671ccb0
Summary:
The deadlock reports (the actual string) were too low level, in order to avoid bug hash clashes. Now that we deduplicate this is less of an issue, so it's an opportunity to improve readability.
```
Potential deadlock.
Trace 1 (starts at `void Interproc.interproc1Bad(InterprocA)`) first locks `this` in class `Interproc*` (line 9 in `void Interproc.interproc1Bad(InterprocA)`) and then locks `b` in class `InterprocA*` (line 14 in `void Interproc.interproc2Bad(InterprocA)`).
Trace 2 (starts at `void InterprocA.interproc1Bad(Interproc)`), first locks `this` in class `InterprocA*` (line 37 in `void InterprocA.interproc1Bad(Interproc)`) and then locks `d` in class `Interproc*` (line 42 in `void InterprocA.interproc2Bad(Interproc)`).
```
Reviewed By: mbouaziz
Differential Revision: D8379328
fbshipit-source-id: bc33983
Summary: Deadlocks can be very noisy, so dedup reports on same line by showing only the one with the shortest trace and a count of the suppressed ones.
Reviewed By: mbouaziz
Differential Revision: D8351148
fbshipit-source-id: 8913db2
Summary: Introduce an annotation that forces the summary of a method to be free of blocking events, without suppressing other reports.
Reviewed By: jeremydubreil
Differential Revision: D8276787
fbshipit-source-id: be9eed8
Summary: Create mechanism for suppressing starvation reports. To do that, refactor and expose a Checkers function.
Reviewed By: mbouaziz
Differential Revision: D8259583
fbshipit-source-id: f5b5a63
Summary:
Use the component of the abstract state `events` to report. This set contains reachability facts about blocking calls and lock acquisitions.
The other component, `order`, contained pairs of a reachable event `e'` from an event option with the semantics that if the option is `None` then we have an element that now goes into `events`, and if the option is `Some e` then the element represents a lock acquired and a trace *from* `e` to `e'`
Now, `order` can be simplified to proper pairs of events, without the option.
Reviewed By: jvillard
Differential Revision: D8227665
fbshipit-source-id: e6f4dac
Summary:
It's useful to test that the bucket a given error is classified as doesn't
change over time without notice.
This records the bucket for *all* the tests, even though some never produce a
bucket. This is to be on the safe size instead of risking to forget adding the
bucket information when the test changes, or when copy/pasting from a test that
doesn't have buckets to one that does.
The implementation is pretty crude: it greps the beginning of the qualifier
string for a `[bucket]`.
Reviewed By: mbouaziz
Differential Revision: D8236393
fbshipit-source-id: b3b1eb9
Summary:
Change the license of the source code from BSD + PATENTS to MIT.
Change `checkCopyright` to reflect the new license and learn some new file
types.
Generated with:
```
git grep BSD | xargs -n 1 ./scripts/checkCopyright -i
```
Reviewed By: jeremydubreil, mbouaziz, jberdine
Differential Revision: D8071249
fbshipit-source-id: 97ca23a
Summary:
There can be multiple reports per line, especially when calling in a method which has itself multiple reports.
When reporting at the callsite, report only the issue with the highest severity (picked manually per type of event).
Deadlocks are not de-duplicated, as they are relatively rare and the info in mupltiple reports may be important.
Reviewed By: mbouaziz
Differential Revision: D8160940
fbshipit-source-id: ea6a5c0
Summary: Track and surface the reasons why a method is assessed to run on the UI thread.
Reviewed By: mbouaziz
Differential Revision: D8096099
fbshipit-source-id: 2403c6c
Summary:
The reported location was always the start of the enclosing procedure, which is wrong in many ways.
A nice side-effect is that some code can then be eliminated and Ondemand.analyze used, avoiding getting the procdescs in the process.
Reviewed By: jeremydubreil
Differential Revision: D8056306
fbshipit-source-id: 67c2c8d
Summary:
Make the starvation checker enabled by default.
Add a deadlock issue type, distinct to starvation, which will be kept for UI thread starvation.
Add checks so that checker will do nothing on non-Java code.
Reviewed By: mbouaziz, ddino
Differential Revision: D7908381
fbshipit-source-id: 889f373