Update the process ID after handling fork/vfork to ensure that
the process plugin reports the correct PID immediately.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D130037
Enable stdio forwarding when nonstop mode is enabled, and disable it
once it is disabled. This makes it possible to cleanly handle stdio
forwarding while running multiple processes in non-stop mode.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128932
Stop all processes and clear notification queues when disabling non-stop
mode. Ensure that no stop notifications are sent for processes stopped
due to the mode switch.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128893
Fix the response to `?` packet for threads that are running at the time
(in non-stop mode). The previous code would wrongly send or queue
an empty response for them.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128879
Introduce a new %Stdio notification category and use it to send process
output asynchronously when running in non-stop mode. This is an LLDB
extension since GDB does not use the 'O' packet for process output,
just for replies to 'qRcmd' packets.
Using the async notification mechanism implies that only the first
output packet is sent immediately to the client. The client needs
to request subsequent notifications (if any) using the new vStdio packet
(that works pretty much like vStopped for the Stop notification queue).
The packet handler in lldb-server tests is updated to handle the async
stdio packets in addition to the regular O packets. However, due
to the implications noted above, it can only handle the first output
packet sent by the server. Subsequent packets need to be explicitly
requested via vStdio.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128849
Improve handling of multiple successive continue packets in non-stop
mode. More specifically:
1. Explicitly send error response (instead of crashing on assertion)
if the user attempts to resume the same process twice. Since we
do not support thread-level non-stop mode, one needs to always stop
the process explicitly before resuming another thread set.
2. Actually stop the process if "vCont;t" is delivered to a running
process. Similarly, we only support stopping all the running threads
simultaneously (via -1) and return an error in any other case.
With this patch, running multiple processes simultaneously is still
unsupported. The patch also employs a hack to avoid enabling stdio
forwarding on "vCont;t" packet. Both of these issues are addressed
by followup patches.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128710
Improve handling of multiple successive continue packets in non-stop
mode. More specifically:
1. Explicitly send error response (instead of crashing on assertion)
if the user attempts to resume the same process twice. Since we
do not support thread-level non-stop mode, one needs to always stop
the process explicitly before resuming another thread set.
2. Actually stop the process if "vCont;t" is delivered to a running
process. Similarly, we only support stopping all the running threads
simultaneously (via -1) and return an error in any other case.
With this patch, running multiple processes simultaneously is still
unsupported. The patch also employs a hack to avoid enabling stdio
forwarding on "vCont;t" packet. Both of these issues are addressed
by followup patches.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128710
Remove m_inferior_prev_state that's not suitable for multiprocess
debugging and that does not seem to be really used at all.
The only use of the variable right now is to "prevent" sending the stop
reason after attach/launch. However, this code is never actually run
since none of the process plugins actually use eStateLaunching or
eStateAttaching. Through adding an assert, I've confirmed that it's
never hit in any of the LLDB tests or while attaching/launching debugged
process via lldb-server and via lldb CLI.
Differential Revision: https://reviews.llvm.org/D128878
Sponsored by: The FreeBSD Foundation
Convert the m_debugged_processes map from NativeProcessProtocol pointers
to structs, and combine the additional set(s) holding the additional
process properties into a flag field inside this struct. This is
desirable since there are more properties to come and having a single
structure with all information should be cleaner and more efficient than
using multiple sets for that.
Suggested by Pavel Labath in D128893.
Differential Revision: https://reviews.llvm.org/D129652
It turns out that cgroup filtering is relatively trivial and works
really nicely. Thid diffs adds automatic cgroup filtering when in
per-cpu mode, unless a new --disable-cgroup-filtering flag is passed in
the start command. At least on Meta machines, all processes are spawned
inside a cgroup by default, which comes super handy, because per cpu
tracing is now much more precise.
A manual test gave me this result
- Without filtering:
Total number of trace items: 36083
Total number of continuous executions found: 229
Number of continuous executions for this thread: 2
Total number of PSB blocks found: 98
Number of PSB blocks for this thread 2
Total number of unattributed PSB blocks found: 38
- With filtering:
Total number of trace items: 87756
Total number of continuous executions found: 123
Number of continuous executions for this thread: 2
Total number of PSB blocks found: 10
Number of PSB blocks for this thread 3
Total number of unattributed PSB blocks found: 2
Filtering gives us great results. The number of instructions collected
more than double (probalby because we have less noise in the trace), and
we have much less unattributed PSBs blocks and unrelated PSBs in
general. The ones that are unrelated probably belong to other processes
in the same cgroup.
Differential Revision: https://reviews.llvm.org/D129257
Previously we recorded AllocationBase as the base address of the region
we get from VirtualQueryEx. However, this is the base of the allocation,
which can later be split into more regions.
So you got stuff like:
[0x00007fff377c0000-0x00007fff377c1000) r-- PECOFF header
[0x00007fff377c0000-0x00007fff37840000) r-x .text
[0x00007fff377c0000-0x00007fff37870000) r-- .rdata
Where all the base addresses were the same.
Instead, use BaseAddress as the base of the region. So we get:
[0x00007fff377c0000-0x00007fff377c1000) r-- PECOFF header
[0x00007fff377c1000-0x00007fff37840000) r-x .text
[0x00007fff37840000-0x00007fff37870000) r-- .rdata
https://docs.microsoft.com/en-us/windows/win32/api/winnt/ns-winnt-memory_basic_information
The added test checks for any overlapping regions which means
if we get the base or size wrong it'll fail. This logic
applies to any OS so the test isn't restricted to Windows.
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D129272
Fix lldb-server in the non-stop + multiprocess mode to exit on vStopped
only if all processes have exited, rather than when the first one exits.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128639
This is currently being done in an ad hoc way, and so for some
commands it isn't being checked. We have the info to make this check,
since commands are supposed to add their arguments to the m_arguments
field of the CommandObject. This change uses that info to check whether
the command received arguments in error.
A handful of commands weren't defining their argument types, I also had
to fix them. And a bunch of commands were checking for arguments by
hand, so I removed those checks in favor of the CommandObject one. That
also meant I had to change some tests that were checking for the ad hoc
error outputs.
Differential Revision: https://reviews.llvm.org/D128453
Implement support for the "t" action that is used to stop a thread.
Normally this action is used only in non-stop mode. However, there's
no technical reason why it couldn't be also used in all-stop mode,
e.g. to express "resume all threads except ..." (`t:...;c`).
While at it, add a more complete test for vCont correctly resuming
a subset of program's threads.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D126983
Now preserving the non-standard behavior of returning "OK" response
when there is no debugged process.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128152
This reverts part of commit 75757c86c6.
It broke the following test:
commands/target/auto-install-main-executable/TestAutoInstallMainExecutable.py
I need more time to figure it out, so I'm reverting the code changes
and marking the tests depending on them xfail.
Introduce a helper function to append GDB Remote Serial Protocol "thread
IDs", with optional PID in multiprocess mode.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128324
Implement the 'T' packet that is used to verify whether the specified
thread belongs to the debugged processes.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128170
Update the `qfThreadInfo` handler to report threads of all debugged
processes and include PIDs when in multiprocess mode.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128152
Extend vCont function to support resuming a process with an arbitrary
PID, that could be different than the one selected via Hc (or no process
at all may be selected). Resuming more than one process simultaneously
is not supported yet.
Remove the ReadTid() method that was only used by Handle_vCont(),
and furthermore it was wrongly using m_current_process rather than
m_continue_process.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D127862
Implement the support for the vKill packet. This is the modern packet
used by the GDB Remote Serial Protocol to kill one of the debugged
processes. Unlike the `k` packet, it has well-defined semantics.
The `vKill` packet takes the PID of the process to kill, and always
replies with an `OK` reply (rather than the exit status, as LLGS does
for `k` packets at the moment). Additionally, unlike the `k` packet
it does not cause the connection to be terminated once the last process
is killed — the client needs to close it explicitly.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D127667
Modify the behavior of the `k` packet to kill all inferiors rather than
just the current one. The specification leaves the exact behavior
of this packet up to the implementation but since vKill is specifically
meant to be used to kill a single process, it seems logical to use `k`
to provide the alternate function of killing all of them.
Move starting stdio forwarding from the "running" response
to the packet handlers that trigger the process to start. This avoids
attempting to start it multiple times when multiple processes are killed
on Linux which implicitly causes LLGS to receive "started" events
for all of them. This is probably also more correct as the ability
to send "O" packets is implied by the continue-like command being issued
(and therefore the client waiting for responses) rather than the start
notification.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D127500
LLDB tries to follow `EXCEPTION_RECORD::ExceptionRecord` to follow the
nested exception chain. In practice this code just causes Access
Violation whenever there is a nested exception. Since there does not
appear to be any code in LLDB that is actually using the nested
exceptions, this change just removes the crashing code and adds a
comment for future reference.
Fixes https://github.com/mstorsjo/llvm-mingw/issues/292
Reviewed By: DavidSpickett
Differential Revision: https://reviews.llvm.org/D128201
This comment became outdated in 053eb35651
(but was moved along); that commit moved the code and the comment
to a separate function, with a separate local variable
`num_of_bytes_read`. On error, the possibly garbage value is never
copied back to the caller's reference, thus the comment is no longer
relevant (and slightly confusing as is).
Differential Revision: https://reviews.llvm.org/D128226
Add a test verifying that plain 'D' packet correctly detaches all
processes.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D127291
Fix ThreadStopInfo struct to include the signal number for all events.
Since signo was not included in the details for fork, vfork
and vforkdone stops, the code incidentally referenced the wrong union
member, resulting in wrong signo being sent.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D127193
Implement the support for %Stop asynchronous notification packet format
in LLGS. This does not implement full support for non-stop mode for
threaded programs -- process plugins continue stopping all threads
on every event. However, it will be used to implement asynchronous
events in multiprocess debugging.
The non-stop protocol is enabled using QNonStop packet. When it is
enabled, the server uses notification protocol instead of regular stop
replies. Since all threads are always stopped, notifications are always
generated for all active threads and copied into stop notification
queue.
If the queue was empty, the initial asynchronous %Stop notification
is sent to the client immediately. The client needs to (eventually)
acknowledge the notification by sending the vStopped packet, in which
case it is popped from the queue and the stop reason for the next thread
is reported. This continues until notification queue is empty again,
in which case an OK reply is sent.
Asychronous notifications are also used for vAttach results and program
exits. The `?` packet uses a hybrid approach -- it returns the first
stop reason synchronously, and exposes the stop reasons for remaining
threads via vStopped queue.
The change includes a test case for a program generating a segfault
on 3 threads. The server is expected to generate a stop notification
for the segfaulting thread, along with the notifications for the other
running threads (with "no stop reason"). This verifies that the stop
reasons are correctly reported for all threads, and that notification
queue works.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D125575
Refactor GDBRemoteCommunicationServerLLGS::SendStopReasonForState()
to accept process as an argument rather than hardcoding
m_current_process, in order to make it work correctly for multiprocess
scenarios.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D127497
Refactor SendStopReplyPacketForThread() to accept process instance
as a parameter rather than use m_current_process. This future-proofs
it for multiprocess support.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D127289
Include the process identifier in the `T` stop responses when
multiprocess extension is enabled (i.e. prepend it to the thread
identifier). Use the exposed identifier to simplify the fork-and-follow
tests.
The LLDB client accounts for the possible PID since the multiprocess
extension support was added in b601c67192.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D127192
Include the process identifier in W/X stop reasons when multiprocess
extensions are enabled.
The LLDB client does not support process identifiers there at the moment
but it parses packets in such a way that their presence does not cause
any problems.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D127191
