Debugger interrupt handling #339
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scratch_buffers_lazy_update_stats() uses the ivykis time state to check if it is time to update the stats about scratch buffers. Do not do that if ivykis is not initialized. This may happen in control threads and the debugger threads that do use scratch buffers but don't use ivykis. Signed-off-by: Balazs Scheidler <[email protected]>
A better solution would be to have a connection specific worker list, and a list of connections. But for now this suffices for my purposes of being able to cancel connection specific workers. Signed-off-by: Balazs Scheidler <[email protected]>
Up to now, control worker threads were only cancelled at exit. Truth be told we never really detected if the peer has disconnected either. This patch implements thread cancellation whenever a connection closes, to detect the closure of the connection comes in a separate patch. Signed-off-by: Balazs Scheidler <[email protected]>
Signed-off-by: Balazs Scheidler <[email protected]>
This will be used to pass over the stdio file descriptors from syslog-ng-ctl so we can attach to the syslog-ng process after it was started in the background. Signed-off-by: Balazs Scheidler <[email protected]>
Signed-off-by: Balazs Scheidler <[email protected]>
Signed-off-by: Balazs Scheidler <[email protected]>
This new command allows to reconnect the stdio streams even if syslog-ng runs in the background. syslog-ng-ctl will be able to pass 3 fds to the syslog-ng process, which will be duplicated into the standard fds and with that syslog-ng will happily start displaying its stdout to that terminal. The ATTACH command itself is threaded and the control socket is only used to indicate that the peers are still alive. syslog-ng will start sending "ALIVE" messages to this stream every second or so. If sending this packet is not successful, the connection is closed and the thread is cancelled. Upon cancellation, the stdio fds are restored to point to /dev/null. Signed-off-by: Balazs Scheidler <[email protected]>
Signed-off-by: Balazs Scheidler <[email protected]>
…ssages Signed-off-by: Balazs Scheidler <[email protected]>
Signed-off-by: Balazs Scheidler <[email protected]>
No command was passed to /dbld/shell in these cases, causing these shells to exit. Signed-off-by: Balazs Scheidler <[email protected]>
This is never inlined anyway, but duplicated into all modules using log_pipe_queue(), it is then better to just have it in one location. Signed-off-by: Balazs Scheidler <[email protected]>
log_pipe_forward_msg() is not inlined anyway, so it will just add an extra branch. Signed-off-by: Balazs Scheidler <[email protected]>
Signed-off-by: Balazs Scheidler <[email protected]>
Checking the global variable pipe_single_step_hook is quite complicated as it is addressed $rip relative, so let's filter out the config related pipes first and remove the same check from the debugger. Signed-off-by: Balazs Scheidler <[email protected]>
The tracer is responsible with the communication between the debugger thread and any worker threads. Up to this point this was not cancellable, e.g. once a breakpoint fired, the worker stopped with no way of cancelling this. With the addition to tracer_cancel() pending breakpoints are let go and at the same time tracer_wait_for_breakpoint() returns as well with a gboolean to indicate whether it was cancelled. Signed-off-by: Balazs Scheidler <[email protected]>
The new debugger_exit() can be called from any thread, triggers the cancellation of the tracer and then waits for the debugger thread to finish. Signed-off-by: Balazs Scheidler <[email protected]>
Signed-off-by: Balazs Scheidler <[email protected]>
…manner The debugger installed the pipe_single_step_hook without locking, but that only works if we do that at startup. Since I want to be able to start the debugger on demand, this needs to sync with any workers that might be executing. On x86 it might be safe to just store the pointer, but other less forgiving architectures (e.g. ARM) may not like that. Let's do this properly. Signed-off-by: Balazs Scheidler <[email protected]>
Signed-off-by: Balazs Scheidler <[email protected]>
…un from the main thread Signed-off-by: Balazs Scheidler <[email protected]>
Signed-off-by: Balazs Scheidler <[email protected]>
The key ingredient to support multi-threaded debugger session is to allow the breakpoint sites to submit debugger_stop_on_breakpoint() calls in parallel so that these requests are queued and no variables are used for the different invocations. The solution is to introduce the BreakpointSite struct, this is where we store state that relates to each distinct breakpoint events. This struct contains both the state the debugger may want to inspect (e.g. msg, pipe) and also the state related to inter-thread communication (e.g. resume_requested). Each such site instances are queued in an internal queue which is then processed by the interactive debugger. Signed-off-by: Balazs Scheidler <[email protected]>
Signed-off-by: Balazs Scheidler <[email protected]>
As long as we have a single signal registrations, these will be executed anyway. IV_SIGNAL_FLAG_EXCLUSIVE are for registrations that want to suppress previous registrations. I intend to use SIGINT in the debugger to break into the debugger to allow executing commands even outside of the pipeline (e.g. setting breakpoints for the future). Signed-off-by: Balazs Scheidler <[email protected]>
Signed-off-by: Balazs Scheidler <[email protected]>
Signed-off-by: Balazs Scheidler <[email protected]>
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This is a continuation o #327 to add interrupt handling to the debugger. At the moment it only works on the original console, syslog-ng-ctl attach debugger does not propagate ctrl+c signals yet.