From: lldb-dev [mailto:lldb-dev-boun...@lists.llvm.org] On Behalf Of Pavel Labath via lldb-dev Sent: Friday, March 17, 2017 4:48 AM
> On 16 March 2017 at 21:43, Kamil Rytarowski <n...@gmx.com> wrote: >> I imagined a possible flow of ResumeAction calls like: >> [Generic/Native framework knows upfront the image of threads within >> debuggee] >> - Resume Thread 2 (PT_RESUME) >> - Suspend Thread 3 (PT_SUSPEND) >> - Set single-step Thread 2 (PT_SETSTEP) >> - Set single-step Thread 4 (PT_SETSTEP) >> - Clear single-step Thread 5 (PT_CLEARSTEP) >> - Resume & emit signal SIGIO (PT_CONTINUE) >> >> In other words: setting properties on threads and pushing the >> PT_CONTINUE button at the end. > None of this is really NetBSD-specific, except the whole-process signal at > the end (which I am going to ignore for now). I mean, the implementation of > it is different, but there is no reason why someone would not want to perform > the same set of actions on Linux for instance. I think most of the work here > should be done on the client. Then, when the user issues the final > "continue", the client sends something like $vCont;s:2;s:4;c:5. Then it's up > to the server to figure out how execute these actions. On NetBSD it would > execute the operations you mention above, while on linux it would do > something like ptrace(PTRACE_SINGLESTEP, 2); ptrace(PTRACE_SINGLESTEP, 4); > ptrace(PTRACE_CONTINUE, 5); (linux lldb-server already supports this > actually, although you may have a hard time convincing the client to send a > packet like that). The big problem with this sequence is non-stop mode. To continue thread 5 while threads 2 and 4 are stepping, and thread 3 is stopped is not legal using all-stop mode. lldb only supports non-stop mode in the gdb-remote communications layer; the guts of the debugger do not support it, and could get very confused when threads 2 and 4 stop, but thread 5 is still running. -- Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project _______________________________________________ lldb-dev mailing list lldb-dev@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-dev
