Commit Graph

73 Commits

Author SHA1 Message Date
Richard Mitton 665068b379 Removed unnecessary call to OpenFirstAvailableMaster.
::Fork already does this internally, so this was simply leaking file handles.

This fixes the problem where the test suite would occasionally run out of file handles.

llvm-svn: 192929
2013-10-17 22:36:28 +00:00
Richard Mitton 0a55835755 Added support for reading thread-local storage variables, as defined using the __thread modifier.
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
2013-10-17 21:14:00 +00:00
Matt Kopec 718be877f8 Add exec support for Linux including common support for POSIX.
llvm-svn: 192319
2013-10-09 19:39:55 +00:00
Michael Sartain 704bf8912e Clean up RegisterContextPOSIX i386 code.
Use 32-bit register enums without gaps on 64-bit hosts.
Don't show 64-bit registers when debugging 32-bit targets.
Add psuedo gpr registers (ax, ah, al, etc.)
Add mmx registers.
Fix TestRegisters.py to not read ymm15 register on 32-bit targets.
Fill out and move gcc/dwarf/gdb register enums to RegisterContext_x86.h

llvm-svn: 192263
2013-10-09 01:28:57 +00:00
Sylvestre Ledru 77c87c0510 If setgid fails for any reason, exit lldb.
scan-build was complaining about:
The return value from the call to 'setgid' is not checked. If an error occurs in 'setgid', the following code may execute with unexpected privileges

llvm-svn: 191618
2013-09-28 15:47:38 +00:00
Michael Sartain c258b3010f Warning cleanup.
llvm-svn: 190942
2013-09-18 15:32:06 +00:00
Andrew Kaylor d4d5499d6c Fixing a problem with thread creation signal order dependency
llvm-svn: 190831
2013-09-17 00:30:24 +00:00
Daniel Malea 1efb418c9d Improve stability of Linux ProcessMonitor by not using fds for synchronization:
- 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
2013-09-16 23:12:18 +00:00
Andrew Kaylor 5e26899331 Stop closing terminal fd from ProcessMonitor. It is owned by ConnectionFileDescriptor.
llvm-svn: 190733
2013-09-14 00:17:31 +00:00
Andrew Kaylor 7d2abdf017 Fixing a problem with inferior exit caused by signal
llvm-svn: 189953
2013-09-04 16:06:04 +00:00
Matt Kopec f8cfe6b73a Handle SI_KERNEL signal code for SIGSEGV exceptions.
Patch by Richard Mitton.

llvm-svn: 188075
2013-08-09 15:26:56 +00:00
Michael Sartain 9f822cd1ec Fix thread name updating in Linux. "thread list" should report correct names always now.
Created new LinuxThread class inherited from POSIXThread and removed linux / freebsd ifdefs
Removed several un-needed set thread name calls

CR (and multiple suggestions): mkopec

llvm-svn: 187545
2013-07-31 23:27:46 +00:00
Ed Maste a56115f785 Correct comment to match class name
llvm-svn: 186509
2013-07-17 14:30:26 +00:00
Matt Kopec 4a32bf58d1 Fix unhandled SIGTRAP signal on Linux causing assertion.
llvm-svn: 186112
2013-07-11 20:01:22 +00:00
Matt Kopec fb6ab54000 Add support for listing inferior thread names on Linux.
llvm-svn: 186033
2013-07-10 20:53:11 +00:00
Andrew Kaylor 6578cb6478 Reverting ProcessMonitor shared pointer changes
llvm-svn: 185981
2013-07-09 22:36:48 +00:00
Andrew Kaylor 214f3a8a78 Use shared pointers to hold the process in ProcessMonitor
llvm-svn: 185946
2013-07-09 16:44:27 +00:00
Matt Kopec b29104467f Fix signal handling for POSIX (only tested on Linux) processes in multi-threaded programs.
Also fix a related issue where if a thread exits after a thread continue, lldb would hang.

llvm-svn: 185944
2013-07-09 15:09:45 +00:00
Ed Maste 428a6784b7 Update comment to match class name
llvm-svn: 184745
2013-06-24 15:04:47 +00:00
Matt Kopec ef14371d3f Fix various build warnings.
llvm-svn: 183140
2013-06-03 18:00:07 +00:00
Matt Kopec 085d6cec1a Add ability to attach/detach to multi-threaded inferiors on Linux.
All running threads will be detected and stopped on attach and all threads get resumed on detach.

llvm-svn: 183049
2013-05-31 22:00:07 +00:00
Andrew Kaylor 93132f504f Adding support for stopping all threads of multithreaded inferiors on Linux. Also adding multithreaded test cases.
llvm-svn: 182809
2013-05-28 23:04:25 +00:00
Matt Kopec 841a5488fb The Linux process plugin wasn't returning the correct linux signals. This fixes that.
Thus, this patch also negates a previous fix for handling SIGCHLD.

llvm-svn: 182166
2013-05-17 22:21:08 +00:00
Matt Kopec a360d7e7a3 ProcessMonitor improvements for Linux.
-Remove tracing of fork/vfork until we add support for tracing inferiors' children on Linux.
-Add trace exec option for ptrace so that we don't receive legacy SIGTRAP signals on execve calls.
-Add handling of SIGCHLD sent by kernel (for now, deliver the signal to the inferior).

llvm-svn: 182153
2013-05-17 19:27:47 +00:00
Daniel Malea dd15b78fc1 Fix Linux warning about missing virtual destructor in Operation classes
llvm-svn: 181712
2013-05-13 17:32:07 +00:00