The difference between this and the previous patch is that now we use
ELF physical addresses only for loading objects into the target (and the
rest of the module load address logic still uses virtual addresses).
Summary:
When writing an object file over gdb-remote, use the vFlashErase, vFlashWrite, and vFlashDone commands if the write address is in a flash memory region. A bare metal target may have this kind of setup.
- Update ObjectFileELF to set load addresses using physical addresses. A typical case may be a data section with a physical address in ROM and a virtual address in RAM, which should be loaded to the ROM address.
- Add support for querying the target's qXfer:memory-map, which contains information about flash memory regions, leveraging MemoryRegionInfo data structures with minor modifications
- Update ProcessGDBRemote to use vFlash commands in DoWriteMemory when the target address is in a flash region
Original discussion at http://lists.llvm.org/pipermail/lldb-dev/2018-January/013093.html
Reviewers: clayborg, labath
Reviewed By: labath
Subscribers: llvm-commits, arichardson, emaste, mgorny, lldb-commits
Differential Revision: https://reviews.llvm.org/D42145
Patch by Owen Shaw <llvm@owenpshaw.net>.
llvm-svn: 327970
This reverts commit r326261 as it introduces inconsistencies in the
handling of load addresses for ObjectFileELF -- some parts of the class
use physical addresses, and some use virtual. This has manifested itself
as us not being able to set the load address of the vdso "module" on
android.
llvm-svn: 326367
Summary:
When writing an object file over gdb-remote, use the vFlashErase, vFlashWrite, and vFlashDone commands if the write address is in a flash memory region. A bare metal target may have this kind of setup.
- Update ObjectFileELF to set load addresses using physical addresses. A typical case may be a data section with a physical address in ROM and a virtual address in RAM, which should be loaded to the ROM address.
- Add support for querying the target's qXfer:memory-map, which contains information about flash memory regions, leveraging MemoryRegionInfo data structures with minor modifications
- Update ProcessGDBRemote to use vFlash commands in DoWriteMemory when the target address is in a flash region
Original discussion at http://lists.llvm.org/pipermail/lldb-dev/2018-January/013093.html
Reviewers: clayborg, labath
Reviewed By: labath
Subscribers: arichardson, emaste, mgorny, lldb-commits
Differential Revision: https://reviews.llvm.org/D42145
Patch by Owen Shaw <llvm@owenpshaw.net>
llvm-svn: 326261
Summary:
There was some confusion in the code about how to represent process
environment. Most of the code (ab)used the Args class for this purpose,
but some of it used a more basic StringList class instead. In either
case, the fact that the underlying abstraction did not provide primitive
operations for the typical environment operations meant that even a
simple operation like checking for an environment variable value was
several lines of code.
This patch adds a separate Environment class, which is essentialy a
llvm::StringMap<std::string> in disguise. To standard StringMap
functionality, it adds a couple of new functions, which are specific to
the environment use case:
- (most important) envp conversion for passing into execve() and likes.
Instead of trying to maintain a constantly up-to-date envp view, it
provides a function which creates a envp view on demand, with the
expectation that this will be called as the very last thing before
handing the value to the system function.
- insert(StringRef KeyEqValue) - splits KeyEqValue into (key, value)
pair and inserts it into the environment map.
- compose(value_type KeyValue) - takes a map entry and converts in back
into "KEY=VALUE" representation.
With this interface most of the environment-manipulating code becomes
one-liners. The only tricky part was maintaining compatibility in
SBLaunchInfo, which expects that the environment entries are accessible
by index and that the returned const char* is backed by the launch info
object (random access into maps is hard and the map stores the entry in
a deconstructed form, so we cannot just return a .c_str() value). To
solve this, I have the SBLaunchInfo convert the environment into the
"envp" form, and use it to answer the environment queries. Extra code is
added to make sure the envp version is always in sync.
(This also improves the layering situation as Args was in the Interpreter module
whereas Environment is in Utility.)
Reviewers: zturner, davide, jingham, clayborg
Subscribers: emaste, lldb-commits, mgorny
Differential Revision: https://reviews.llvm.org/D41359
llvm-svn: 322174
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:
This patch adds support for sending strings along with
error codes in the reply packets. The implementation is
based on the feedback recieved in the lldb-dev mailing
list. The patch also adds an extra packet for the client
to query if the server has the capability to provide
strings along with error replys.
Reviewers: labath, jingham, sas, lldb-commits, clayborg
Reviewed By: labath, clayborg
Differential Revision: https://reviews.llvm.org/D34945
llvm-svn: 307768
Summary:
It had a dependency on StringConvert and file reading code, which is not
in Utility. I've replaced that code by equivalent llvm operations.
I've added a unit test to demonstrate that parsing a file still works.
Reviewers: zturner, jingham
Subscribers: kubamracek, mgorny, lldb-commits
Differential Revision: https://reviews.llvm.org/D34625
llvm-svn: 306394
Summary:
The changes consist of new packets for trace manipulation and
trace collection. The new packets are also documented. The packets
are capable of providing custom trace specific parameters to start
tracing and also retrieve such configuration from the server.
Reviewers: clayborg, lldb-commits, tberghammer, labath, zturner
Reviewed By: clayborg, labath
Subscribers: krytarowski, lldb-commits
Differential Revision: https://reviews.llvm.org/D32585
llvm-svn: 303972
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
If QPassSignals packaet is supported by lldb-server, lldb-client will
utilize it and ask the server to ignore signals that don't require stops
or notifications.
Such signals will be immediately re-injected into inferior to continue
normal execution.
Differential Revision: https://reviews.llvm.org/D30520
llvm-svn: 297231
The mock server was listening for only one packet (I forgot to put a loop around
it), which caused the client to stall in debug builds, as the timeout there is
1000 seconds. In case of a release builds the test would just silently succeed as
the tested function does not check or report errors (which should be fixed).
This fixes the test by adding the server loop. Since the test was taking quite a
long time now (8s), I have added a parameter to control the amount of data sent
(default 4MB), and call it with a smaller value in the test, to make the test run
faster.
llvm-svn: 285992
Summary:
Most of the changes are very straight-forward, the only tricky part was the
"packet speed-test" function, which is very time-heavy. As the function was
completely untested, I added a quick unit smoke test for it.
Reviewers: clayborg, zturner
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D25391
llvm-svn: 285602
Summary:
This adds the jModulesInfo packet, which is the equivalent of qModulesInfo, but it enables us to
query multiple modules at once. This makes a significant speed improvement in case the
application has many (over a hundred) modules, and the communication link has a non-negligible
latency. This functionality is accessed by ProcessGdbRemote::PrefetchModuleSpecs(), which does
the caching. GetModuleSpecs() is modified to first consult the cache before asking the remote
stub. PrefetchModuleSpecs is currently only called from POSIX-DYLD dynamic loader plugin, after
it reads the list of modules from the inferior memory, but other uses are possible.
This decreases the attach time to an android application by about 40%.
Reviewers: clayborg
Subscribers: tberghammer, lldb-commits, danalbert
Differential Revision: https://reviews.llvm.org/D24236
llvm-svn: 280919
*** 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:
This is a preparatory commit for D22914, where I'd like to replace this mutex by an R/W lock
(which is also not recursive). This required a couple of changes:
- The only caller of Read/WriteRegister, GDBRemoteRegisterContext class, was already acquiring
the mutex, so these functions do not need to. All functions which now do not take a lock, take
an lock argument instead, to remind the caller of this fact.
- GetThreadSuffixSupported() was being called from locked and unlocked contexts (including
contexts where the process was running, and the call would fail if it did not have the result
cached). I have split this into two functions, one which computes the thread suffix support and
caches it (this one always takes the lock), and another, which returns the cached value (and
never needs to take the lock). This feels quite natural as ProcessGdbRemote was already
pre-caching this value at the start.
Reviewers: clayborg
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D23802
llvm-svn: 279725
Summary:
The tricky part here was that the exisiting implementation of WriteAllRegisters was expecting
hex-encoded data (as that was what the first implementation I replaced was using, but here we had
binary data to begin with. I thought the read/write register functions would be more useful if
they handled the hex-encoding themselves (all the other client functions provide the responses in
a more-or-less digested form). The read functions return a DataBuffer, so they can allocate as
much memory as they need to, while the write functions functions take an llvm::ArrayRef, as that
can be constructed from pretty much anything.
Reviewers: clayborg
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D23659
llvm-svn: 279232
Take 2, with missing cmake line fixed. Build tested on
Ubuntu 14.04 with clang-3.6.
See docs/structured_data/StructuredDataPlugins.md for details.
differential review: https://reviews.llvm.org/D22976
reviewers: clayborg, jingham
llvm-svn: 279202
Summary:
Before this, each function had a copy of the code which handled appending of the thread suffix to
the packet (or using $Hg instead). I have moved that code into a single function and made
everyone else use that. The function takes the partial packet as a StreamString rvalue reference,
to avoid a copy and to remind the users that the packet will have undeterminate contents after
the call.
This also fixes the incorrect formatting of the QRestoreRegisterState packet in case thread
suffix is not supported.
Reviewers: clayborg
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D23604
llvm-svn: 279040
Summary:
When saving/restoring registers the GDBRemoteRegisterContext class was manually constructing
the register save/restore packets. This creates appropriate helper functions in
GDBRemoteCommunicationClient, and switches the class to use those. It also removes what a
duplicate packet send in some of those functions, a thing that I can only attribute to a bad
merge artefact.
I also add a test framework for testing gdb-remote client functionality and add tests for the new
functions I introduced. I'd like to be able to test the register context changes in isolation as
well, but currently there doesn't seem to be a way to reasonably construct a standalone register
context object, so we'll have to rely on the end-to-end tests to verify that.
Reviewers: clayborg
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D23553
llvm-svn: 278915
Despite its comment, the function is only used in the Client class, and its presence was merely
complicating mock implementation in unit tests.
llvm-svn: 278785
Resumbitting the commit after fixing the following problems:
- broken unit tests on windows: incorrect gtest usage on my part (TEST vs. TEST_F)
- the new code did not correctly handle the case where we went to interrupt the process, but it
stopped due to a different reason - the interrupt request would remain queued and would
interfere with the following "continue". I also added a unit test for this case.
This reapplies r277156 and r277139.
llvm-svn: 278118
This reverts commit r277139, because:
- broken unittest on windows (likely typo on my part)
- seems to break TestCallThatRestart (needs investigation)
llvm-svn: 277154
SendContinuePacketAndWaitForResponse was huge function with very complex interactions with
several other functions (SendAsyncSignal, SendInterrupt, SendPacket). This meant that making any
changes to how packet sending functions and threads interact was very difficult and error-prone.
This change does not add any functionality yet, it merely paves the way for future changes. In a
follow-up, I plan to add the ability to have multiple query packets in flight (i.e.,
request,request,response,response instead of the usual request,response sequences) and use that
to speed up qModuleInfo packet processing.
Here, I introduce two special kinds of locks: ContinueLock, which is used by the continue thread,
and Lock, which is used by everyone else. ContinueLock (atomically) sends a continue packet, and
blocks any other async threads from accessing the connection. Other threads create an instance of
the Lock object when they want to access the connection. This object, while in scope prevents the
continue from being send. Optionally, it can also interrupt the process to gain access to the
connection for async processing.
Most of the syncrhonization logic is encapsulated within these two classes. Some of it still
had to bleed over into the SendContinuePacketAndWaitForResponse, but the function is still much
more manageable than before -- partly because of most of the work is done in the ContinueLock
class, and partly because I have factored out a lot of the packet processing code separate
functions (this also makes the functionality more easily testable). Most importantly, there is
none of syncrhonization code in the async thread users -- as far as they are concerned, they just
need to declare a Lock object, and they are good to go (SendPacketAndWaitForResponse is now a
very thin wrapper around the NoLock version of the function, whereas previously it had over 100
lines of synchronization code). This will make my follow up changes there easy.
I have written a number of unit tests for the new code and I have ran the test suite on linux and
osx with no regressions.
Subscribers: tberghammer
Differential Revision: https://reviews.llvm.org/D22629
llvm-svn: 277139
This finally removes the use of the Mutex and Condition classes. This is an
intricate patch as the Mutex and Condition classes were tied together.
Furthermore, many places had slightly differing uses of time values. Convert
timeout values to relative everywhere to permit the use of
std::chrono::duration, which is required for the use of
std::condition_variable's timeout. Adjust all Condition and related Mutex
classes over to std::{,recursive_}mutex and std::condition_variable.
This change primarily comes at the cost of breaking the TracingMutex which was
based around the Mutex class. It would be possible to write a wrapper to
provide similar functionality, but that is beyond the scope of this change.
llvm-svn: 277011
debugserver jGetSharedCacheInfo packet instead of reading
the dyld internal data structures directly. This code is
(currently) only used for ios native lldb's - I should really
move this ObjectFileMachO::GetProcessSharedCacheUUID method
somewhere else, it makes less and less sense being in the
file reader.
<rdar://problem/25251243>
llvm-svn: 276369
This is a pretty straightforward first pass over removing a number of uses of
Mutex in favor of std::mutex or std::recursive_mutex. The problem is that there
are interfaces which take Mutex::Locker & to lock internal locks. This patch
cleans up most of the easy cases. The only non-trivial change is in
CommandObjectTarget.cpp where a Mutex::Locker was split into two.
llvm-svn: 269877
Summary:
eRegisterKindProcessPlugin is used to store the register
indices used by the remote, and eRegisterKindLLDB is used
to store the internal lldb register indices. However, we're currently
using the lldb indices instead of the process plugin indices
when sending p/P packets. This will break if the remote uses
non-contiguous register indices.
Reviewers: jasonmolenda, clayborg
Subscribers: lldb-commits, sas
Differential Revision: http://reviews.llvm.org/D19305
llvm-svn: 267466
This is a packet which allows the remote gdb stub to ask for the address
of a symbol in the process. lldb sends the packet (offering to provide
addresses for symbol names) after every solib loaded. I changed lldb so
that once the stub has indicated that it doesn't need any more symbol
addresses, lldb will stop sending the qSymbol:: packet on new solib loads.
This can yield a performance benefit over slower communication links when
there are many solibs involved.
<rdar://problem/23310049>
llvm-svn: 257569
Summary:
Some debug servers don't support it so there's no point in spamming
this.
Reviewers: clayborg
Subscribers: fjricci, lldb-commits
Differential Revision: http://reviews.llvm.org/D15972
llvm-svn: 257116
The standard remote debugging workflow with gdb is to start the
application on the remote host under gdbserver (e.g.: gdbserver :5039
a.out) and then connect to it with gdb.
The same workflow is supported by debugserver/lldb-gdbserver with a very
similar syntax but to access all features of lldb we need to be
connected also to an lldb-platform instance running on the target.
Before this change this had to be done manually with starting a separate
lldb-platform on the target machine and then connecting to it with lldb
before connecting to the process.
This change modifies the behavior of "platform connect" with
automatically connecting to the process instance if it was started by
the remote platform. With this command replacing gdbserver in a gdb
based worflow is usually as simple as replacing the command to execute
gdbserver with executing lldb-platform.
Differential revision: http://reviews.llvm.org/D14952
llvm-svn: 255016
SUMMARY:
The patch supports TAAwatch:addr packet. The patch also sets m_watchpoints_trigger_after_instruction
to eLazyBoolNo when qHostInfo or qWatchpointSupportInfo is not supported by the target.
Reviewers: jingham, clayborg
Subscribers: nitesh.jain, mohit.bhakkad, sagar, bhushan and lldb-commits
Differential Revision: http://reviews.llvm.org/D11747
llvm-svn: 244865
jGetLoadedDynamicLibrariesInfos. This packet is similar to
qXfer:libraries:read except that lldb supplies the number of solibs
that should be reported about, and the start address for the list
of them. At the initial process launch we'll read the full list
of solibs linked by the process -- at this point we could be using
qXfer:libraries:read -- but on subsequence solib-loaded notifications,
we'll be fetching a smaller number of solibs, often only one or two.
A typical Mac/iOS GUI app may have a couple hundred different
solibs loaded - doing all of the loads via memory reads takes
a couple of megabytes of traffic between lldb and debugserver.
Having debugserver summarize the load addresses of all the solibs
and sending it in JSON requires a couple of hundred kilobytes
of traffic. It's a significant performance improvement when
communicating over a slower channel.
This patch leaves all of the logic for loading the libraries
in DynamicLoaderMacOSXDYLD -- it only call over ot ProcesGDBRemote
to get the JSON result.
If the jGetLoadedDynamicLibrariesInfos packet is not implemented,
the normal technique of using memory read packets to get all of
the details from the target will be used.
<rdar://problem/21007465>
llvm-svn: 241964
- Avoid sending the qfThreadInfo, qsThreadInfo packets if we have a stop reply packet with the threads already (save 2 round trip packets)
- Include the qname, qserial and qkind in the JSON info
- Report the qname, qserial and qkind to the thread so it can cache it to avoid many packets on MacOSX and iOS
- Don't clear all discoverable settings when we exec, just the ones we need to saves 1-5 packets for each exec.
llvm-svn: 240988
A few extras were fixed
- Symbol::GetAddress() now returns an Address object, not a reference. There were places where people were accessing the address of a symbol when the symbol's value wasn't an address symbol. On MacOSX, undefined symbols have a value zero and some places where using the symbol's address and getting an absolute address of zero (since an Address object with no section and an m_offset whose value isn't LLDB_INVALID_ADDRESS is considered an absolute address). So fixing this required some changes to make sure people were getting what they expected.
- Since some places want to access the address as a reference, I added a few new functions to symbol:
Address &Symbol::GetAddressRef();
const Address &Symbol::GetAddressRef() const;
Linux test suite passes just fine now.
<rdar://problem/21494354>
llvm-svn: 240702
A "qSymbol::" is sent when shared libraries have been loaded by hooking into the Process::ModulesDidLoad() function from within ProcessGDBRemote. This function was made virtual so that the ProcessGDBRemote version is called, which then first calls the Process::ModulesDidLoad(), and then it queries for any symbol lookups that the remote GDB server might want to do.
This allows debugserver to request the "dispatch_queue_offsets" symbol so that it can read the queue name, queue kind and queue serial number and include this data as part of the stop reply packet. Previously each thread would have to do 3 memory reads in order to read the queue name.
This is part of reducing the number of packets that are sent between LLDB and the remote GDB server.
<rdar://problem/21494354>
llvm-svn: 240466
This patch adds a listener to the AynscThread in ProcessGDBRemote, specifically for dealing with any async notification packets.
From the broadcast our listener receives we can process the notify packet from the event data. A handler function then sets the thread stop info from this packet, and updates lldb by setting the process private state to stopped. Allowing the async thread to go back to sleep and getting the main thread to handle the implications of a state change.
When sending a vCont in nonstop mode we also get a different reply from all-stop mode, an OK response as opposed to a stop reply. So a condition is added to handle this and set the process state without the stop-reply data.
Reviewers: clayborg
Subscribers: lldb-commits, labath, ted, aidan.dodds, deepak2427
Differential Revision: http://reviews.llvm.org/D10544
llvm-svn: 240397
We have been working on reducing the packet count that is sent between LLDB and the debugserver on MacOSX and iOS. Our approach to this was to reduce the packets required when debugging multiple threads. We currently make one qThreadStopInfoXXXX call (where XXXX is the thread ID in hex) per thread except the thread that stopped with a stop reply packet. In order to implement multiple thread infos in a single reply, we need to use structured data, which means JSON. The new jThreadsInfo packet will attempt to retrieve all thread infos in a single packet. The data is very similar to the stop reply packets, but packaged in JSON and uses JSON arrays where applicable. The JSON output looks like:
[
{ "tid":1580681,
"metype":6,
"medata":[2,0],
"reason":"exception",
"qaddr":140735118423168,
"registers": {
"0":"8000000000000000",
"1":"0000000000000000",
"2":"20fabf5fff7f0000",
"3":"e8f8bf5fff7f0000",
"4":"0100000000000000",
"5":"d8f8bf5fff7f0000",
"6":"b0f8bf5fff7f0000",
"7":"20f4bf5fff7f0000",
"8":"8000000000000000",
"9":"61a8db78a61500db",
"10":"3200000000000000",
"11":"4602000000000000",
"12":"0000000000000000",
"13":"0000000000000000",
"14":"0000000000000000",
"15":"0000000000000000",
"16":"960b000001000000",
"17":"0202000000000000",
"18":"2b00000000000000",
"19":"0000000000000000",
"20":"0000000000000000"},
"memory":[
{"address":140734799804592,"bytes":"c8f8bf5fff7f0000c9a59e8cff7f0000"},
{"address":140734799804616,"bytes":"00000000000000000100000000000000"}
]
}
]
It contains an array of dicitionaries with all of the key value pairs that are normally in the stop reply packet. Including the expedited registers. Notice that is also contains expedited memory in the "memory" key. Any values in this memory will get included in a new L1 cache in lldb_private::Process where if a memory read request is made and that memory request fits into one of the L1 memory cache blocks, it will use that memory data. If a memory request fails in the L1 cache, it will fall back to the L2 cache which is the same block sized caching we were using before these changes. This allows a process to expedite memory that you are likely to use and it reduces packet count. On MacOSX with debugserver, we expedite the frame pointer backchain for a thread (up to 256 entries) by reading 2 pointers worth of bytes at the frame pointer (for the previous FP and PC), and follow the backchain. Most backtraces on MacOSX and iOS now don't require us to read any memory!
We will try these packets out and if successful, we should port these to lldb-server in the near future.
<rdar://problem/21494354>
llvm-svn: 240354
For some communication channels, sending large packets can be very
slow. In those cases, it may be faster to compress the contents of
the packet on the target device and decompress it on the debug host
system. For instance, communicating with a device using something
like Bluetooth may be an environment where this tradeoff is a good one.
This patch adds a new field to the response to the "qSupported" packet
(which returns a "qXfer:features:" response) -- SupportedCompressions
and DefaultCompressionMinSize. These tell you what the remote
stub can support.
lldb, if it wants to enable compression and can handle one of those
algorithms, it can send a QEnableCompression packet specifying the
algorithm and optionally the minimum packet size to use compression
on. lldb may have better knowledge about the best tradeoff for
a given communication channel.
I added support to debugserver an lldb to use the zlib APIs
(if -DHAVE_LIBZ=1 is in CFLAGS and -lz is in LDFLAGS) and the
libcompression APIs on Mac OS X 10.11 and later
(if -DHAVE_LIBCOMPRESSION=1). libz "zlib-deflate" compression.
libcompression can support deflate, lz4, lzma, and a proprietary
lzfse algorithm. libcompression has been hand-tuned for Apple
hardware so it should be preferred if available.
debugserver currently only adds the SupportedCompressions when
it is being run on an Apple watch (TARGET_OS_WATCH). Comment
that #if out from RNBRemote.cpp if you want to enable it to
see how it works. I haven't tested this on a native system
configuration but surely it will be slower to compress & decompress
the packets in a same-system debug session.
I haven't had a chance to add support for this to
GDBRemoteCommunciationServer.cpp yet.
<rdar://problem/21090180>
llvm-svn: 240066
Summary:
This should solve the issue of sending denormalized paths over gdb-remote
if we stick to GetPath(false) in GDBRemoteCommunicationClient, and let the
server handle any denormalization.
Reviewers: ovyalov, zturner, vharron, clayborg
Reviewed By: clayborg
Subscribers: tberghammer, emaste, lldb-commits
Differential Revision: http://reviews.llvm.org/D9728
llvm-svn: 238604
qEcho:%s
where '%s' is any valid string. The response to this packet is the exact packet itself with no changes, just reply with what you received!
This will help us to recover from packets timing out much more gracefully. Currently if a packet times out, LLDB quickly will hose up the debug session. For example, if we send a "abc" packet and we expect "ABC" back in response, but the "abc" command takes longer than the current timeout value this will happen:
--> "abc"
<-- <<<error: timeout>>>
Now we want to send "def" and get "DEF" back:
--> "def"
<-- "ABC"
We got the wrong response for the "def" packet because we didn't sync up with the server to clear any current responses from previously issues commands.
The fix is to modify GDBRemoteCommunication::WaitForPacketWithTimeoutMicroSecondsNoLock() so that when it gets a timeout, it syncs itself up with the client by sending a "qEcho:%u" where %u is an increasing integer, one for each time we timeout. We then wait for 3 timeout periods to sync back up. So the above "abc" session would look like:
--> "abc"
<-- <<<error: timeout>>> 1 second
--> "qEcho:1"
<-- <<<error: timeout>>> 1 second
<-- <<<error: timeout>>> 1 second
<-- "abc"
<-- "qEcho:1"
The first timeout is from trying to get the response, then we know we timed out and we send the "qEcho:1" packet and wait for 3 timeout periods to get back in sync knowing that we might actually get the response for the "abc" packet in the mean time...
In this case we would actually succeed in getting the response for "abc". But lets say the remote GDB server is deadlocked and will never response, it would look like:
--> "abc"
<-- <<<error: timeout>>> 1 second
--> "qEcho:1"
<-- <<<error: timeout>>> 1 second
<-- <<<error: timeout>>> 1 second
<-- <<<error: timeout>>> 1 second
We then disconnect and say we lost connection.
We might also have a bad GDB server that just dropped the "abc" packet on the floor. We can still recover in this case and it would look like:
--> "abc"
<-- <<<error: timeout>>> 1 second
--> "qEcho:1"
<-- "qEcho:1"
Then we know our remote GDB server is still alive and well, and it just dropped the "abc" response on the floor and we can continue to debug.
<rdar://problem/21082939>
llvm-svn: 238530
Summary:
This patch is the beginnings of support for Non-stop mode in the remote protocol. Letting a user examine stopped threads, while other threads execute freely.
Non-stop mode is enabled using the setting target.non-stop-mode, which sends a QNonStop packet when establishing the remote connection.
Changes are also made to treat the '?' stop reply packet differently in non-stop mode, according to spec https://sourceware.org/gdb/current/onlinedocs/gdb/Remote-Non_002dStop.html#Remote-Non_002dStop.
A setting for querying the remote for default thread on setup is also included.
Handling of '%' async notification packets will be added next.
Reviewers: clayborg
Subscribers: lldb-commits, ADodds, ted, deepak2427
Differential Revision: http://reviews.llvm.org/D9656
llvm-svn: 237239
