Commit Graph

17 Commits

Author SHA1 Message Date
Greg Clayton 830c81d511 Fixed an issue that could cause debugserver to return two stop reply packets ($T packets) for one \x03 interrupt. The problem was that when a \x03 byte is sent to debugserver while the process is running, and up calling:
rnb_err_t
RNBRemote::HandlePacket_stop_process (const char *p)
{
    if (!DNBProcessInterrupt(m_ctx.ProcessID()))
        HandlePacket_last_signal (NULL);
    return rnb_success;
}

In the call to DNBProcessInterrupt we did:

nub_bool_t
DNBProcessInterrupt(nub_process_t pid)
{
    MachProcessSP procSP;
    if (GetProcessSP (pid, procSP))
        return procSP->Interrupt();
    return false;
}

This would always return false. It would cause HandlePacket_stop_process to always call "HandlePacket_last_signal (NULL);" which would send an extra stop reply packet _if_ the process is stopped. On a machine with enough cores, it would call DNBProcessInterrupt(...) and then HandlePacket_last_signal(NULL) so quickly that it will never send out an extra stop reply packet. But if the machine is slow enough or doesn't have enough cores, it could cause the call to HandlePacket_last_signal() to actually succeed and send an extra stop reply packet. This would cause problems up in GDBRemoteCommunicationClient::SendContinuePacketAndWaitForResponse() where it would get the first stop reply packet and then possibly return or execute an async packet. If it returned, then the next packet that was sent will get the second stop reply as its response. If it executes an async packet, the async packet will get the wrong response.

To fix this I did the following:
1 - in debugserver, I fixed "bool MachProcess::Interrupt()" to return true if it sends the signal so we avoid sending the stop reply twice on slower machines
2 - Added a log line to RNBRemote::HandlePacket_stop_process() to say if we ever send an extra stop reply so we will see this in the darwin console output if this does happen
3 - Added response validators to StringExtractorGDBRemote so that we can verify some responses to some packets. 
4 - Added validators to packets that often follow stop reply packets like the "m" packet for memory reads, JSON packets since "jThreadsInfo" is often sent immediately following a stop reply.
5 - Modified GDBRemoteCommunicationClient::SendPacketAndWaitForResponseNoLock() to validate responses. Any "StringExtractorGDBRemote &response" that contains a valid response verifier will verify the response and keep looking for correct responses up to 3 times. This will help us get back on track if we do get extra stop replies. If a StringExtractorGDBRemote does not have a response validator, it will accept any packet in response.
6 - In GDBRemoteCommunicationClient::SendPacketAndWaitForResponse we copy the response validator from the "response" argument over into m_async_response so that if we send the packet by interrupting the running process, we can validate the response we actually get in GDBRemoteCommunicationClient::SendContinuePacketAndWaitForResponse()
7 - Modified GDBRemoteCommunicationClient::SendContinuePacketAndWaitForResponse() to always check for an extra stop reply packet for 100ms when the process is interrupted. We were already doing this because we might interrupt a process with a \x03 packet, yet the process was in the process of stopping due to another reason. This race condition could cause an extra stop reply packet because the GDB remote protocol says if a \x03 packet is sent while the process is stopped, we should send a stop reply packet back. Now we always check for an extra stop reply packet when we manually interrupt a process.

The issue was showing up when our IDE would attempt to set a breakpoint while the process is running and this would happen:

--> \x03
<-- $T<stop reply 1>
--> z0,AAAAA,BB (set breakpoint)
<-- $T<stop reply 1> (incorrect extra stop reply packet)
--> c
<-- OK (response from z0 packet)

Now all packet traffic was off by one response. Since we now have a validator on the response for "z" packets, we do this:

--> \x03
<-- $T<stop reply 1>
--> z0,AAAAA,BB (set breakpoint)
<-- $T<stop reply 1> (Ignore this because this can't be the response to z0 packets)
<-- OK -- (we are back on track as this is a valid response to z0)
...

As time goes on we should add more packet validators.

<rdar://problem/22859505>

llvm-svn: 265086
2016-04-01 00:41:29 +00:00
Jason Molenda c611a74059 Upstreaming the apple internal changes that accumulated during the
previous release.  Most of the diffs are duplication in the xcode
project file caused by adding a "debugserver-mini" target.  Jim
Ingham added support for a new SPI needed to request app launches
on iOS.  Greg Clayton added code to indicate the platform of the
binary (macosx, ios, watchos, tvos) based on Mach-O load commands.
Jason Molenda added code so debugserver will identify when it is
running on a tvos/watchos device to lldb.

llvm-svn: 251091
2015-10-23 02:49:51 +00:00
Dawn Perchik f71e8370d1 Fix lldb build on older OSX versions after svn commit r244716
Older OSX versions don't define NSOperatingSystemVersion, so building
lldb gets: error: unknown type name 'NSOperatingSystemVersion'
This patch fixes the build by having GetOSVersionNumbers return false if
__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101000, causing lldb to
behave the same as it did before the commit.

Reviewed by: jasonmolenda
Subscribers: lldb-commits
Differential Revision: http://reviews.llvm.org/D12396

llvm-svn: 246138
2015-08-27 03:42:56 +00:00
Jason Molenda 6acc86c3f5 Have debugserver send the OS version string plus
major, minor, and patchlevel in the qHostInfo reply.  
Document that qHostInfo may report major/minor/patch
separately / in addition to the version: combination.

<rdar://problem/22125465> 

llvm-svn: 244716
2015-08-12 03:27:33 +00:00
Bruce Mitchener 8a67bf7298 Add UNUSED_IF_ASSERT_DISABLED and apply it.
Summary:
This replaces (void)x; usages where they x was subsequently
involved in an assertion with this macro to make the
intent more clear.

Reviewers: clayborg

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D11451

llvm-svn: 243074
2015-07-24 00:23:29 +00:00
Greg Clayton 97f9e40e3a Don't water JSONGenerator objects down into ObjectSP's too early so that we can call member functions specific to dictionaries and arrays without calling GetAsDictionary() or GetAsArray() on them.
llvm-svn: 242917
2015-07-22 18:15:30 +00:00
Bruce Mitchener a026de0585 Fix warnings.
Reviewers: clayborg

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D11404

llvm-svn: 242913
2015-07-22 17:31:44 +00:00
Jason Molenda 20ee21bde6 Add a another packet to the gdb-remote protocol,
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
2015-07-10 23:15:22 +00:00
Greg Clayton ee2ed52584 Fix debugserver warnings on MacOSX.
llvm-svn: 231692
2015-03-09 19:45:23 +00:00
Jason Molenda 0f7828cf6d Clarify the launch style for debugserver to use.
<rdar://problem/18786645> 

llvm-svn: 220761
2014-10-28 03:15:33 +00:00
Jason Molenda 36a216eefc Increase the gdb-remote packet timeout for the first packet we send
to the remote side (QStartNoAckMode) - it may take a little longer
than normal to get a reply.

In debugserver, hardcode the priority for several threads so they
aren't de-prioritized when a user app is using system resources.
Also, set the names of the threads.

<rdar://problem/17509866>

llvm-svn: 213828
2014-07-24 01:36:24 +00:00
Bruce Mitchener aaa0ba31a9 Fix typos.
llvm-svn: 212553
2014-07-08 18:05:41 +00:00
Bruce Mitchener d93c4a3339 Fix typos.
llvm-svn: 212132
2014-07-01 21:22:11 +00:00
Jason Molenda 705b180964 Initial merge of some of the iOS 8 / Mac OS X Yosemite specific
lldb support.  I'll be doing more testing & cleanup but I wanted to
get the initial checkin done.

This adds a new SBExpressionOptions::SetLanguage API for selecting a
language of an expression.

I added adds a new SBThread::GetInfoItemByPathString for retriving
information about a thread from that thread's StructuredData.

I added a new StructuredData class for representing
key-value/array/dictionary information (e.g. JSON formatted data).
Helper functions to read JSON and create a StructuredData object,
and to print a StructuredData object in JSON format are included.

A few Cocoa / Cocoa Touch data formatters were updated by Enrico
to track changes in iOS 8 / Yosemite.

Before we query a thread's extended information, the system runtime may 
provide hints to the remote debug stub that it will use to retrieve values
out of runtime structures.  I added a new SystemRuntime method 
AddThreadExtendedInfoPacketHints which allows the SystemRuntime to add 
key-value type data to the initial request that we send to the remote stub.

The thread-format formatter string can now retrieve values out of a thread's
extended info structured data.  The default thread-format string picks up
two of these - thread.info.activity.name and thread.info.trace_messages.

I added a new "jThreadExtendedInfo" packet in debugserver; I will
add documentation to the lldb-gdb-remote.txt doc soon.  It accepts
JSON formatted arguments (most importantly, "thread":threadnum) and
it returns a variety of information regarding the thread to lldb
in JSON format.  This JSON return is scanned into a StructuredData
object that is associated with the thread; UI layers can query the
thread's StructuredData to see if key-values are present, and if
so, show them to the user.  These key-values are likely to be
specific to different targets with some commonality among many
targets.  For instance, many targets will be able to advertise the
pthread_t value for a thread.

I added an initial rough cut of "thread info" command which will print
the information about a thread from the jThreadExtendedInfo result.
I need to do more work to make this format reasonably.

Han Ming added calls into the pmenergy and pmsample libraries if
debugserver is run on Mac OS X Yosemite to get information about the
inferior's power use.

I added support to debugserver for gathering the Genealogy information
about threads, if it exists, and returning it in the jThreadExtendedInfo
JSON result.

llvm-svn: 210874
2014-06-13 02:37:02 +00:00
Greg Clayton bb49289023 Allow for a task port to change when we exec.
llvm-svn: 207699
2014-04-30 20:27:01 +00:00
Greg Clayton 4296c221d3 Fixed an issue where we would try to interrupt a process while it is in the process of naturally stopping due to another reason (breakpoint, or step).
Added a new MachProcess::Interrupt() which correctly tracks such cases and "does the right thing".

<rdar://problem/16593556>

llvm-svn: 207139
2014-04-24 19:54:32 +00:00
Jason Molenda a332978b2a lldb arm64 import.
These changes were written by Greg Clayton, Jim Ingham, Jason Molenda.

It builds cleanly against TOT llvm with xcodebuild.  I updated the
cmake files by visual inspection but did not try a build.  I haven't
built these sources on any non-Mac platforms - I don't think this
patch adds any code that requires darwin, but please let me know if
I missed something.

In debugserver, MachProcess.cpp and MachTask.cpp were renamed to
MachProcess.mm and MachTask.mm as they picked up some new Objective-C
code needed to launch processes when running on iOS.

llvm-svn: 205113
2014-03-29 18:54:20 +00:00