Hi, Eric,
This looks like a repost? I mentioned that we should also set done = 1
for a failed setup_tracer_devpaths() call, and I was hoping you'd
include that in a new version (or at least comment on whether you
thought it was a good idea). Sorry if that wasn't clear!
The change here looks good to me.
-Jeff
Eric Sandeen <sandeen@xxxxxxxxxx> writes:
> # blktrace -o - /dev/sda /dev/sdb /dev/sdc
>
> has to be SIGKILLed if BLKTRACESETUP fails for any or all of the devices
> listed. (I simulated this by just catching one of the devices in
> setup_buts(), skipping the ioctl, and doing ret++).
>
> This seems to be because with "-o -" on the command line, use_tracer_devpaths()
> sees piped_output set, so we call process_trace_bufs which ends up waiting on
> (!done) and "done" is never set. i.e.
>
> atexit(exit_tracing)
> wait_tracers
> if (use_tracer_devpaths()) // true because "-o -"
> process_trace_bufs
> while (wait_empty_entries())
> wait_empty_entries
> while (!done ... )
> <loop forever>
>
> I think this can be avoided by just setting "done = 1" before returning
> when setup_buts() fails in run_tracers().
>
> Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx>
> ---
>
> diff --git a/blktrace.c b/blktrace.c
> index 3444fbb..038b2cb 100644
> --- a/blktrace.c
> +++ b/blktrace.c
> @@ -2684,8 +2684,10 @@ static int run_tracers(void)
> if (net_mode == Net_client)
> printf("blktrace: connecting to %s\n", hostname);
>
> - if (setup_buts())
> + if (setup_buts()) {
> + done = 1;
> return 1;
> + }
>
> if (use_tracer_devpaths()) {
> if (setup_tracer_devpaths())
