This patch moves creates a thread abstraction that represents a
thread running inside the LLDB process. This is a replacement for
otherwise using lldb::thread_t, and provides a platform agnostic
interface to managing these threads.
Differential Revision: http://reviews.llvm.org/D5198
Reviewed by: Jim Ingham
llvm-svn: 217460
On FreeBSD ptrace(PT_KILL) is used to terminate the traced process
(as if PT_CONTINUE had been used with SIGKILL as the signal to be
delivered), and is the desired behaviour for ProcessPOSIX::DoDestroy.
On Linux, after ptrace(PTRACE_KILL) the traced process still exists
and can be interrogated. It is only upon resume that it exits as though
it received SIGKILL.
As the Linux PTRACE_KILL behaviour is not used by LLDB, rename
BringProcessIntoLimbo to Kill, and change the implementation to simply
call kill() instead of using ptrace.
Thanks to Todd F for testing (Ubuntu 12.04, gcc 4.8.2).
Sponsored by: DARPA, AFRL
Differential Revision: http://llvm-reviews.chandlerc.com/D3159
llvm-svn: 205337
To make this work this patch extends LLDB to:
- Explicitly track the link_map address for each module. This is effectively the module handle, not sure why it wasn't already being stored off anywhere. As an extension later, it would be nice if someone were to add support for printing this as part of the modules list.
- Allow reading the per-thread data pointer via ptrace. I have added support for Linux here. I'll be happy to add support for FreeBSD once this is reviewed. OS X does not appear to have __thread variables, so maybe we don't need it there. Windows support should eventually be workable along the same lines.
- Make DWARF expressions track which module they originated from.
- Add support for the DW_OP_GNU_push_tls_address DWARF opcode, as generated by gcc and recent versions of clang. Earlier versions of clang (such as 3.2, which is default on Ubuntu right now) do not generate TLS debug info correctly so can not be supported here.
- Understand the format of the pthread DTV block. This is where it gets tricky. We have three basic options here:
1) Call "dlinfo" or "__tls_get_addr" on the inferior and ask it directly. However this won't work on core dumps, and generally speaking it's not a good idea for the debugger to call functions itself, as it has the potential to not work depending on the state of the target.
2) Use libthread_db. This is what GDB does. However this option requires having a version of libthread_db on the host cross-compiled for each potential target. This places a large burden on the user, and would make it very hard to cross-debug from Windows to Linux, for example. Trying to build a library intended exclusively for one OS on a different one is not pleasant. GDB sidesteps the problem and asks the user to figure it out.
3) Parse the DTV structure ourselves. On initial inspection this seems to be a bad option, as the DTV structure (the format used by the runtime to manage TLS data) is not in fact a kernel data structure, it is implemented entirely in useerland in libc. Therefore the layout of it's fields are version and OS dependent, and are not standardized.
However, it turns out not to be such a problem. All OSes use basically the same algorithm (a per-module lookup table) as detailed in Ulrich Drepper's TLS ELF ABI document, so we can easily write code to decode it ourselves. The only question therefore is the exact field layouts required. Happily, the implementors of libpthread expose the structure of the DTV via metadata exported as symbols from the .so itself, designed exactly for this kind of thing. So this patch simply reads that metadata in, and re-implements libthread_db's algorithm itself. We thereby get cross-platform TLS lookup without either requiring third-party libraries, while still being independent of the version of libpthread being used.
Test case included.
llvm-svn: 192922
- ProcessMonitor::[Do|Serve]Operation no longer depend on file descriptors!
- removed unused member functions CloseFD and EnableIPC
- add semaphores to signal when an Operation is ready to be processed/complete.
This commit fixes a bug that was identified under stress-testing (i.e. build
LLVM while running tests) that led to LLDB becoming unresponsive because the
read/write operations on file descriptors in ProcessMonitor were not checked.
Other test runner improvement/convenience:
- pickup environment variables LLDB_LINUX_LOG and LLDB_LINUX_LOG_OPTIONS to
enable (Linux) logging when running the test suite. Example usage:
$ LLDB_LINUX_LOG="mylog.txt" LLDB_LINUX_LOG_OPTIONS="process thread" python dotest.py
llvm-svn: 190820
- Eliminated the use of static for methods that read m_register_infos, so that these routines can be implemented in the base class.
- Eliminated m_register_infos in the base class because this is not used when derived classes call UpdateRegisterInfo.
- Also moved the namespace using declarations from headers to source files.
Thanks to Daniel and Samuel for their review feedback.
llvm-svn: 181538
- Handle EINVAL return code from ptrace(GETSIGINFO, ...): not an error, but 'group-stop' state on Linux
- propagate SIGSTOP to inferior in above case
- this commit resolves the failure in expression_command/timeout testcase
Thanks to Sean Callanan & Matt Kopec for helping debug this problem
llvm-svn: 168523
This patch fixes an issue where if lldb fails to attach to a process (ie. invalid pid) on Linux, the process monitor thread gets stuck waiting for a signal from the attach thread, which never comes due to not being signaled. It also implements StopOpThread which is used for both attach/launch cases as I'm not aware of any special handling needed for the attach case. Also, propagate 'Error' from the Detach function instead of using a bool.
llvm-svn: 166055
a new POSIX platform. It also contains fixes for 64bit FreeBSD.
The patch is based on changes by Mark Peek <mp@FreeBSD.org> and
"K. Macy" <kmacy@freebsd.org> in their github repo located at
https://github.com/fbsd/lldb.
llvm-svn: 147609
solve the build break due to the lack of this method.
It also propose a solution to the API changes in RegisterContext.
I upgraded also the the python version in the makefile. My linux
installation has python2.7 and AFAIK also the latest ubuntu
has this version of python so maybe is worth upgrading.
Patch by Marco Minutoli <mminutoli@gmail.com>
[Note: I had to hand merge in the diffs since patch thinks it is a corrupt patch.]
llvm-svn: 131313
This patch upgrades the Linux process plugin to handle a larger range of signal
events. For example, we can detect when the inferior has "crashed" and why,
interrupt a running process, deliver an arbitrary signal, and so on.
llvm-svn: 128547
This patch removes a potential race condition between a process monitor thread
and its parent waiting to interrogate the success/failure of the launch.
llvm-svn: 123803
This component is still at an early stage, but allows for simple
breakpoint/step-over operations and basic process control.
The makefiles are set up to build the plugin under Linux only.
llvm-svn: 109318
Zachary Turner