- Add collection of context switches per cpu grouped with the per-cpu intel pt traces.
- Move the state handling from the interl pt trace class to the PerfEvent one.
- Add support for stopping and enabling perf event groups.
- Return context switch entries as part of the jLLDBTraceGetState response.
- Move the triggers of whenever the process stopped or resumed. Now the will-resume notification is in a better location, which will ensure that we'll capture the instructions that will be executed.
- Remove IntelPTSingleBufferTraceUP. The unique pointer was useless.
- Add unit tests
Differential Revision: https://reviews.llvm.org/D125897
When tracing on per-core mode, we are tracing all processes, which means
that after hitting a breakpoint, our process will stop running (thus
producing no more tracing data) but other processes will continue
writing to our trace buffers. This causes a big data loss for our trace.
As a way to remediate this, I'm adding some logic to pause and unpause
tracing based on the target's state. The earlier we do it the better,
however, I'm not adding the trigger at the earliest possible point for
simplicity of this diff. Later we can improve that part.
Differential Revision: https://reviews.llvm.org/D124962
- Rename IntelPTManager class and files to IntelPTCollector
- Change GetTimestampCounter API to general trace counter API,
GetCounter
Differential Revision: https://reviews.llvm.org/D121711
Implement the qXfer:siginfo:read that is used to read the siginfo_t
(extended signal information) for the current thread. This is currently
implemented on FreeBSD and Linux.
Differential Revision: https://reviews.llvm.org/D117113
The lldb-server code is currently set up in a way that each
NativeProcess instance does its own waitpid handling. This works fine
for BSDs, where the code can do a waitpid(process_id), and get
information for all threads in that process.
The situation is trickier on linux, because waitpid(pid) will only
return information for the main thread of the process (one whose tid ==
pid). For this reason the linux code does a waitpid(-1), to get
information for all threads. This was fine while we were supporting just
a single process, but becomes a problem when we have multiple processes
as they end up stealing each others events.
There are two possible solutions to this problem:
- call waitpid(-1) centrally, and then dispatch the events to the
appropriate process
- have each process call waitpid(tid) for all the threads it manages
This patch implements the second approach. Besides fitting better into
the existing design, it also has the added benefit of ensuring
predictable ordering for thread/process creation events (which come in
pairs -- one for the parent and one for the child). The first approach
OTOH, would make this ordering even more complicated since we would
have to keep the half-threads hanging in mid-air until we find the
process we should attach them to.
The downside to this approach is an increased number of syscalls (one
waitpid for each thread), but I think we're pretty far from optimizing
things like this, and so the cleanliness of the design is worth it.
The included test reproduces the circumstances which should demonstrate
the bug (which manifests as a hung test), but I have not been able to
get it to fail. The only place I've seen this failure modes are very
rare hangs in the thread sanitizer tests (tsan forks an addr2line
process to produce its error messages).
Differential Revision: https://reviews.llvm.org/D116372
The MonitorCallback function was assuming that the "exited" argument is
set whenever a thread exits, but the caller was only setting that flag
for the main thread.
This patch deletes the argument altogether, and lets MonitorCallback
compute what it needs itself.
This is almost NFC, since previously we would end up in the
"GetSignalInfo failed for unknown reasons" branch, which was doing the
same thing -- forgetting about the thread.
This is implemented using the QMemTags packet, as specified
by GDB in:
https://sourceware.org/gdb/current/onlinedocs/gdb/General-Query-Packets.html#General-Query-Packets
(recall that qMemTags was previously added to read tags)
On receipt of a valid packet lldb-server will:
* align the given address and length to granules
(most of the time lldb will have already done this
but the specification doesn't guarantee it)
* Repeat the supplied tags as many times as needed to cover
the range. (if tags > range we just use as many as needed)
* Call ptrace POKEMTETAGS to write the tags.
The ptrace step will loop just like the tag read does,
until all tags are written or we get an error.
Meaning that if ptrace succeeds it could be a partial write.
So we call it again and if we then get an error, return an error to
lldb.
We are not going to attempt to restore tags after a partial
write followed by an error. This matches the behaviour of the
existing memory writes.
The lldb-server tests have been extended to include read and
write in the same test file. With some updated function names
since "qMemTags" vs "QMemTags" isn't very clear when they're
next to each other.
Reviewed By: omjavaid
Differential Revision: https://reviews.llvm.org/D105180
This adds memory tag reading using the new "qMemTags"
packet and ptrace on AArch64 Linux.
This new packet is following the one used by GDB.
(https://sourceware.org/gdb/current/onlinedocs/gdb/General-Query-Packets.html)
On AArch64 Linux we use ptrace's PEEKMTETAGS to read
tags and we assume that lldb has already checked that the
memory region actually has tagging enabled.
We do not assume that lldb has expanded the requested range
to granules and expand it again to be sure.
(although lldb will be sending aligned ranges because it happens
to need them client side anyway)
Also we don't assume untagged addresses. So for AArch64 we'll
remove the top byte before using them. (the top byte includes
MTE and other non address data)
To do the ptrace read NativeProcessLinux will ask the native
register context for a memory tag manager based on the
type in the packet. This also gives you the ptrace numbers you need.
(it's called a register context but it also has non register data,
so it saves adding another per platform sub class)
The only supported platform for this is AArch64 Linux and the only
supported tag type is MTE allocation tags. Anything else will
error.
Ptrace can return a partial result but for lldb-server we will
be treating that as an error. To succeed we need to get all the tags
we expect.
(Note that the protocol leaves room for logical tags to be
read via qMemTags but this is not going to be implemented for lldb
at this time.)
Reviewed By: omjavaid
Differential Revision: https://reviews.llvm.org/D95601
Enable reporting fork/vfork events to the server when supported.
At this moment, this is used only to test the server code, as real
client does not report fork-events and vfork-events as supported.
Differential Revision: https://reviews.llvm.org/D100208
This commit has caused the following tests to be flaky:
TestThreadSpecificBpPlusCondition.py
TestExitDuringExpression.py
The exact cause is not known yet, but since both tests deal with
threads, my guess is it has something to do with the tracking of
creation of new threads (which the commit touches upon).
This reverts the following commits:
d01bff8cbd,
ba62ebc48e,
e761b6b4c5,
a345419ee0.
Watch for fork(2)/vfork(2) (also fork/vfork-style clone(2) on Linux)
notifications and explicitly detach the forked child process, and add
initial tests for these cases. The code covers FreeBSD, Linux
and NetBSD process plugins. There is no new user-visible functionality
provided -- this change lays foundations over subsequent work on fork
support.
Differential Revision: https://reviews.llvm.org/D98822
This implements the interactive trace start and stop methods.
This diff ended up being much larger than I anticipated because, by doing it, I found that I had implemented in the beginning many things in a non optimal way. In any case, the code is much better now.
There's a lot of boilerplate code due to the gdb-remote protocol, but the main changes are:
- New tracing packets: jLLDBTraceStop, jLLDBTraceStart, jLLDBTraceGetBinaryData. The gdb-remote packet definitions are quite comprehensive.
- Implementation of the "process trace start|stop" and "thread trace start|stop" commands.
- Implementaiton of an API in Trace.h to interact with live traces.
- Created an IntelPTDecoder for live threads, that use the debugger's stop id as checkpoint for its internal cache.
- Added a functionality to stop the process in case "process tracing" is enabled and a new thread can't traced.
- Added tests
I have some ideas to unify the code paths for post mortem and live threads, but I'll do that in another diff.
Differential Revision: https://reviews.llvm.org/D91679
Introduce mips64 support to match the legacy FreeBSD plugin. Similarly
to the legacy plugin, the code does not support FPU registers at the
moment. The support for them will be submitted separately as it
requires changes to the register context shared by both plugins.
This also includes software single-stepping support that is moved from
the Linux plugin into a common Utility class. The FreeBSD code also
starts explicitly ignoring EINVAL from PT_CLEARSTEP since this is easier
to implement than checking whether hardware single-stepping were used.
Differential Revision: https://reviews.llvm.org/D95802
Depends on D89283.
The goal of this packet (jTraceGetSupportedType) is to be able to query the gdb-server for the tracing technology that can work for the current debuggeer, which can make the user experience simpler but allowing the user to simply type
thread trace start
to start tracing the current thread without even telling the debugger to use "intel-pt", for example. Similarly, `thread trace start [args...]` would accept args beloging to the working trace type.
Also, if the user typed
help thread trace start
We could directly show the help information of the trace type that is supported for the target, or mention instead that no tracing is supported, if that's the case.
I added some simple tests, besides, when I ran this on my machine with intel-pt support, I got
$ process plugin packet send "jTraceSupportedType"
packet: jTraceSupportedType
response: {"description":"Intel Processor Trace","pluginName":"intel-pt"}
On a machine without intel-pt support, I got
$ process plugin packet send "jTraceSupportedType"
packet: jTraceSupportedType
response: E00;
Reviewed By: clayborg, labath
Differential Revision: https://reviews.llvm.org/D90490
This patch adds support for the _M and _m gdb-remote packets, which
(de)allocate memory in the inferior. This works by "injecting" a
m(un)map syscall into the inferior. This consists of:
- finding an executable page of memory
- writing the syscall opcode to it
- setting up registers according to the os syscall convention
- single stepping over the syscall
The advantage of this approach over calling the mmap function is that
this works even in case the mmap function is buggy or unavailable. The
disadvantage is it is more platform-dependent, which is why this patch
only works on X86 (_32 and _64) right now. Adding support for other
linux architectures should be easy and consist of defining the
appropriate syscall constants. Adding support for other OSes depends on
the its ability to do a similar trick.
Differential Revision: https://reviews.llvm.org/D89124
Summary:
This is the third patch to improve module loading in a series that started here (where I explain the motivation and solution): D62499
Add functions to read the r_debug location to know where the linked list of loaded libraries are so I can generate the `xfer:libraries-svr4` packet.
I'm also using this function to implement `GetSharedLibraryInfoAddress` that was "not implemented" for linux.
Most of this code was inspired by the current ds2 implementation here: https://github.com/facebook/ds2/blob/master/Sources/Target/POSIX/ELFProcess.cpp.
Reviewers: clayborg, xiaobai, labath
Reviewed By: clayborg, labath
Subscribers: emaste, krytarowski, mgorny, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D62501
llvm-svn: 363458
Summary:
This is the second patch to improve module loading in a series that started here (where I explain the motivation and solution): https://reviews.llvm.org/D62499
I need to read the aux vector to know where the r_debug map with the loaded libraries are.
The AuxVector class was made generic so it could be reused between the POSIX-DYLD plugin and NativeProcess*. The class itself ended up in the ProcessUtility plugin.
Reviewers: clayborg, xiaobai, labath, JDevlieghere
Reviewed By: clayborg, labath, JDevlieghere
Subscribers: emaste, JDevlieghere, mgorny, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D62500
llvm-svn: 363098
A lot of comments in LLDB are surrounded by an ASCII line to delimit the
begging and end of the comment.
Its use is not really consistent across the code base, sometimes the
lines are longer, sometimes they are shorter and sometimes they are
omitted. Furthermore, it looks kind of weird with the 80 column limit,
where the comment actually extends past the line, but not by much.
Furthermore, when /// is used for Doxygen comments, it looks
particularly odd. And when // is used, it incorrectly gives the
impression that it's actually a Doxygen comment.
I assume these lines were added to improve distinguishing between
comments and code. However, given that todays editors and IDEs do a
great job at highlighting comments, I think it's worth to drop this for
the sake of consistency. The alternative is fixing all the
inconsistencies, which would create a lot more churn.
Differential revision: https://reviews.llvm.org/D60508
llvm-svn: 358135
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Summary:
This function existed (with identical code) in both NativeProcessLinux
and NativeProcessNetBSD, and it is likely that it would be useful to any
future implementation of NativeProcessProtocol.
Therefore I move it to the base class.
Reviewers: krytarowski
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D52719
llvm-svn: 343683
Summary:
This function encodes the knowledge of whether the PC points to the
breakpoint instruction of the one following it after the breakpoint is
"hit". This behavior mainly(*) depends on the architecture and not on the
OS, so it makes sense for it to be implemented in the base class, where
it can be shared between different implementations (Linux and NetBSD
atm).
(*) It is possible for an OS to expose a different API, perhaps by doing
some fixups in the kernel. In this case, the implementation can override
this function to implement custom behavior.
Reviewers: krytarowski, zturner
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D52532
llvm-svn: 343409
The two existing implementations have the function implemented
identically, and there's no reason to believe that this would be
different for other implementations.
llvm-svn: 342167
This recommits r341487, which was reverted due to failing tests with
clang. It turned out I had incorrectly expected that the literal arrays
passed to ArrayRef constructor will have static (permanent) storage.
This was only the case with gcc, while clang was constructing them on
stack, leading to dangling pointers when the function returns.
The fix is to explicitly assign static storage duration to the opcode
arrays.
llvm-svn: 341758
return the opcode as a Expected<ArrayRef> instead of a
Status+pointer+size combo.
I also move the linux implementation to the base class, as the trap
opcodes are likely to be the same for all/most implementations of the
class (except the arm one, where linux chooses a different opcode than
what the arm spec recommends, which I keep linux-specific).
llvm-svn: 341487
This brings the LLDB configuration closer to LLVM's and removes visual
clutter in the source code by removing the @brief commands from
comments.
This patch also reflows the paragraphs in all doxygen comments.
See also https://reviews.llvm.org/D46290.
Differential Revision: https://reviews.llvm.org/D46321
llvm-svn: 331373
The rationale here is that ArchSpec is used throughout the codebase,
including in places which should not depend on the rest of the code in
the Core module.
This commit touches many files, but most of it is just renaming of
#include lines. In a couple of cases, I removed the #include ArchSpec
line altogether, as the file was not using it. In one or two places,
this necessitated adding other #includes like lldb-private-defines.h.
llvm-svn: 318048
Summary:
These functions used to return bool to signify whether they were able to
retrieve the data. This is redundant because the ArchSpec and ByteOrder
already have their own "invalid" states, *and* because both of the
current implementations (linux, netbsd) can always provide a valid
result.
This allows us to simplify bits of the code handling these values.
Reviewers: eugene, krytarowski
Subscribers: javed.absar, lldb-commits
Differential Revision: https://reviews.llvm.org/D39733
llvm-svn: 317779
Summary:
The NativeThread class is useless without the containing process (and in
some places it is already assuming the process is always around). This
makes it clear that the NativeProcessProtocol is the object owning the
threads, and makes the destruction order deterministic (first threads,
then process). The NativeProcess is the only thing holding a thread
unique_ptr, and methods that used to hand out thread shared pointers now
return raw pointers or references.
Reviewers: krytarowski, eugene
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D35618
llvm-svn: 316007
Summary:
It defined a couple of types (condition_t) which we don't use anymore,
as we have c++11 goodies now. I remove these definitions.
Also it unnecessarily included a couple of headers which weren't
necessary for it's operation. I remove these, and place the includes in
the relevant files (usually .cpp, usually in Host code) which use them.
This allows us to reduce namespace pollution in most of the lldb files
which don't need the OS-specific definitions.
Reviewers: zturner, jingham
Subscribers: ki.stfu, lldb-commits
Differential Revision: https://reviews.llvm.org/D35113
llvm-svn: 308304
Summary:
The usage of shared_from_this forces us to separate construction and
initialization phases, because shared_from_this() is not available in
the constructor (or destructor). The shared semantics are not necessary,
as we always have a clear owner of the native process class
(GDBRemoteCommunicationServerLLDB object). Even if we need shared
semantics in the future (which I think we should strongly avoid),
reverting this will not be necessary -- the owners can still easily
store the native process object in a shared pointer if they really want
to -- this just prevents the knowledge of that from leaking into the
class implementation.
After this a NativeThread object will hold a reference to the parent
process (instead of a weak_ptr) -- having a process instance always
available allows us to simplify some logic in this class (some of it was
already simplified because we were asserting that the process is
available, but this makes it obvious).
Reviewers: krytarowski, eugene, zturner
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D35123
llvm-svn: 308282
Summary:
This replaces the static functions used for creating
NativeProcessProtocol instances with a factory pattern, and modernizes
the interface of the new class in the process -- I use llvm::Expected
instead of the Status+value combo. I also move some of the common code
(like the Delegate registration into the base class). The new
arrangement has multiple benefits:
- it removes the NativeProcess*** dependency from Process/gdb-remote
(which for example means that liblldb no longer pulls in this code).
- it enables unit testing of the GDBRemoteCommunicationServerLLGS class
(by providing a mock Native Process).
- serves as another example on how to use the llvm::Expected class (I
couldn't get rid of the Initialize-type functions completely here
because of the use of shared_from_this, but that's the next thing on
my list here)
Tests still pass on Linux and I've made sure NetBSD compiles after this.
Reviewers: zturner, eugene, krytarowski
Subscribers: srhines, lldb-commits, mgorny
Differential Revision: https://reviews.llvm.org/D33778
llvm-svn: 307390
Summary:
This patch implements support for Intel(R) Processor Trace
in lldb server. The changes have support for
starting/stopping and reading the trace data. The code
is only available on Linux versions where the perf
attributes for aux buffers are available.
The patch also consists of Unit tests for testing the
core buffer reading function.
Reviewers: lldb-commits, labath, clayborg, zturner, tberghammer
Reviewed By: labath, clayborg
Subscribers: mgorny
Differential Revision: https://reviews.llvm.org/D33674
llvm-svn: 306516
Summary:
A number of places were trying to decode the result of wait(). Add a simple
utility function that does that and a struct that encapsulates the
decoded result. Then also provide a pretty-printer for that class.
Reviewers: zturner, krytarowski, eugene
Subscribers: lldb-commits, mgorny
Differential Revision: https://reviews.llvm.org/D33998
llvm-svn: 305689
This renames the LLDB error class to Status, as discussed
on the lldb-dev mailing list.
A change of this magnitude cannot easily be done without
find and replace, but that has potential to catch unwanted
occurrences of common strings such as "Error". Every effort
was made to find all the obvious things such as the word "Error"
appearing in a string, etc, but it's possible there are still
some lingering occurences left around. Hopefully nothing too
serious.
llvm-svn: 302872
Summary:
GetAuxvData was causing dependencies from host to target and linux
process modules. It also does not fit netbsd use case, as there we can
only read the auxiliary vector with ptrace, which is better done in the
process plugin, with the other ptrace calls.
I resolve these issues by moving the freebsd and linux versions into the
relevant process plugins. In case of linux, this required adding an
interface in NativeProcessProtocol. The empty definitions on other
platforms can simply be removed.
To get the code compiling I had to add ProcessGdbRemote -> ProcessLinux
dependency, which was not caught before because we depended on it
transitively.
Reviewers: zturner, emaste
Subscribers: srhines, mgorny, lldb-commits
Differential Revision: https://reviews.llvm.org/D31031
llvm-svn: 298066
Previously it parsed /proc/<pid>/maps for every module separately
resulting in a very slow response time. This CL add some caching and
optimizes the implementation to improve the code from O(n*m) to O(n+m)
where n is the number of modules requested and m is the number of
files mapped into memory.
Differential revision: https://reviews.llvm.org/D28233
llvm-svn: 290895
*** to conform to clang-format’s LLVM style. This kind of mass change has
*** two obvious implications:
Firstly, merging this particular commit into a downstream fork may be a huge
effort. Alternatively, it may be worth merging all changes up to this commit,
performing the same reformatting operation locally, and then discarding the
merge for this particular commit. The commands used to accomplish this
reformatting were as follows (with current working directory as the root of
the repository):
find . \( -iname "*.c" -or -iname "*.cpp" -or -iname "*.h" -or -iname "*.mm" \) -exec clang-format -i {} +
find . -iname "*.py" -exec autopep8 --in-place --aggressive --aggressive {} + ;
The version of clang-format used was 3.9.0, and autopep8 was 1.2.4.
Secondly, “blame” style tools will generally point to this commit instead of
a meaningful prior commit. There are alternatives available that will attempt
to look through this change and find the appropriate prior commit. YMMV.
llvm-svn: 280751
Summary:
We've had two copies of code for launching processes:
- one in NativeProcessLinux, used for launching debugged processes
- one in ProcessLauncherAndroid, used on android for launching all other kinds of processes
These have over time acquired support for various launch options, but neither supported all of
them. I now replace them with a single implementation ProcessLauncherLinux, which supports all
the options the individual versions supported and set it to be used to launch all processes on
linux.
This also works around the ETXTBSY issue on android when the process is started from the platform
instance, as that used to go through the version which did not contain the workaround.
Reviewers: tberghammer
Subscribers: tberghammer, danalbert, srhines, lldb-commits
Differential Revision: https://reviews.llvm.org/D22457
llvm-svn: 276288
Summary:
This removes one level of indirection, which was just packing and repacking launch args into
different structures. NFC.
Reviewers: tberghammer
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D22357
llvm-svn: 275544
Summary:
We are seeing infrequent failures to launch the inferior process on android. The failing call
seems to be execve(). This adds more logging to see the actual error reported by the call.
Reviewers: tberghammer
Subscribers: tberghammer, lldb-commits, danalbert
Differential Revision: http://reviews.llvm.org/D22039
llvm-svn: 274624
Summary:
This removes the last usage of the Platform plugin in NPL. It was being
used for determining the architecture of the debugged process. I replace
the call that went through the Platform plugin with a lower level call
on the ObjectFile directly.
Reviewers: tberghammer
Subscribers: uweigand, nitesh.jain, omjavaid, lldb-commits
Differential Revision: http://reviews.llvm.org/D21324
llvm-svn: 272686
NPL now assumes it is running from a single thread now, so its thread-safety is untested
anyway (and if that assumption is broken, we'll have bigger problems (due to ptrace restrictions)
than a couple of missing mutexes).
llvm-svn: 269640
Summary:
On arm64, linux<=4.4 and Android<=M there is a bug, which prevents single-stepping from working when
the system comes back from suspend, because of incorrectly initialized CPUs. This did not really
affect Android<M, because it did not use software suspend, but it is a problem for M, which uses
suspend (doze) quite extensively. Fortunately, it seems that the first CPU is not affected by
this bug, so this commit implements a workaround by forcing the inferior to execute on the first
cpu whenever we are doing single stepping.
While inside, I have moved the implementations of Resume() and SingleStep() to the thread class
(instead of process).
Reviewers: tberghammer, ovyalov
Subscribers: aemerson, rengolin, tberghammer, danalbert, srhines, lldb-commits
Differential Revision: http://reviews.llvm.org/D17509
llvm-svn: 261636
Summary:
Most NPL private functions took (shared) pointers to threads as arguments. This meant that the
callee could not be sure if the pointer was valid and so most functions were peppered with
null-checks. Now, I move the check closer to the source, and pass around the threads as
references (which are then assumed to be valid).
Reviewers: tberghammer
Subscribers: lldb-commits
Differential Revision: http://reviews.llvm.org/D12237
llvm-svn: 245831
Walter Erquinigo