Commit Graph

14 Commits

Author SHA1 Message Date
Jim Ingham dca2bc4081 Add a mutex to the ThreadPlanStackMap class.
We've seen very occasional crashes that we can only explain by
simultaneous access to the ThreadPlanStackMap, so I'm adding a
mutex to protect it.

Differential Revision: https://reviews.llvm.org/D124029
2022-04-29 11:07:22 -07:00
Kazu Hirata 2d303e6781 Remove redundant return and continue statements (NFC)
Identified with readability-redundant-control-flow.
2021-12-24 23:17:54 -08:00
Quinn Pham 04cbfa950e [lldb][NFC] Inclusive Language: rename master plan to controlling plan
[NFC] As part of using inclusive language within the llvm project, this patch
renames master plan to controlling plan in lldb.

Reviewed By: jingham

Differential Revision: https://reviews.llvm.org/D113019
2021-11-11 15:04:44 -06:00
Dave Lee 41d0b20cc9 [lldb] Avoid moving ThreadPlanSP from plans vector
Change `ThreadPlanStack::PopPlan` and `::DiscardPlan` to not do the following:

1. Move the last plan, leaving a moved `ThreadPlanSP` in the plans vector
2. Operate on the last plan
3. Pop the last plan off the plans vector

This leaves a period of time where the last element in the plans vector has been moved. I am not sure what, if any, guarantees there are when doing this, but it seems like it would/could leave a null `ThreadPlanSP` in the container. There are asserts in place to prevent empty/null `ThreadPlanSP` instances from being pushed on to the stack, and so this could break that invariant during multithreaded access to the thread plan stack.

An open question is whether this use of `std::move` was the result of a measure performance problem.

Differential Revision: https://reviews.llvm.org/D106171
2021-08-01 10:40:04 -07:00
Jim Ingham 6eb576dcff Add a mutex to guard access to the ThreadPlanStack class
We've seen reports of crashes (none we've been able to reproduce
locally) that look like they are caused by concurrent access to a
thread plan stack.  It looks like there are error paths when an
interrupt request to debugserver times out that cause this problem.

The thread plan stack access is never in a hot loop, and there
aren't enough of them for the extra data member to matter, so
there's really no good reason not to protect the access.

Adding the mutex revealed a couple of places where we were
using "auto" in an iteration when we should have been using
"auto &" - we didn't intend to copy the stack - and I fixed
those as well.

Except for preventing crashes this should be NFC.

Differential Revision: https\://reviews.llvm.org/D106122
2021-07-16 15:40:58 -07:00
Dave Lee e7361c8ecc [lldb] Rename QueueFundamentalPlan to QueueBasePlan (NFC)
Minor change for naming consistency.

Differential Revision: https://reviews.llvm.org/D97985
2021-03-04 21:46:49 -08:00
Dave Lee 22f0aa0d9e [lldb] Remove unused ThreadPlan tracer utilities (NFC)
Delete unused `EnableTracer()` and `SetTracer()` functions on `Thread`. By deleting
these, their `ThreadPlan` counterparts also become unused.

Then, by deleting `ThreadPlanStack::EnableTracer`, `EnableSingleStep` becomes unused.
With no more callers to `EnableSingleStep`, the value `m_single_step` is always true and
can be removed as well.

Differential Revision: https://reviews.llvm.org/D96666
2021-02-15 17:59:25 -08:00
Dave Lee 90b8ae016b [lldb] Remove unused ThreadPlanStack::GetStackOfKind (NFC)
This function isn't used.

Differential Revision: https://reviews.llvm.org/D95411
2021-01-26 09:22:25 -08:00
Walter Erquinigo 4bb6244871 [ThreadPlan] fix exec on Linux 2021-01-25 11:30:48 -08:00
Pavel Labath ff18a6acea [lldb] Fix -Wparentheses in ThreadPlanStack.cpp 2020-04-15 12:47:57 +02:00
Benjamin Kramer 873b79b867 Don't access reference to a vector after pop_back
This is undefined behavior. Found by asan's detect_container_overflow.
2020-04-07 23:10:58 +02:00
Eric Christopher 3ccd454c10 Fix unused variable, format, and format string warnings.
NFC.
2020-04-03 17:58:59 -07:00
Jim Ingham 1893065d7b Allow the ThreadPlanStackMap to hold the thread plans for threads
that were not reported by the OS plugin.  To facilitate this, move
adding/updating the ThreadPlans for a Thread to the ThreadPlanStackMap.
Also move dumping thread plans there as well.

Added some tests for "thread plan list" and "thread plan discard" since
I didn't seem to have written any originally.

Differential Revision: https://reviews.llvm.org/D76814
2020-04-03 14:56:28 -07:00
Jim Ingham 61e8e6882d Move thread plan stacks into the Process, indexed by TID.
Differential Revision: https://reviews.llvm.org/D75880
2020-04-03 14:56:28 -07:00