[igt-dev] [PATCH i-g-t] lib: Show stacktrace when terminated by runner

[Petri Latvala]

On Tue, Nov 27, 2018 at 01:22:16PM +0000, Chris Wilson wrote:
> The igt_runner sends a SIGTERM to ask the test to cleanly exit upon an
> external timeout. It is useful to know what the code was doing when the
> timeout occurred, just in case it was unexpectedly stuck. However, since
> we use SIGTERM internally to marshal helper processes, we want to keep
> SIGTERM quiet, and so opt to use SIGQUIT for the timeout request
> instead.
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Petri Latvala <petri.latvala at intel.com>


Reviewed-by: Petri Latvala <petri.latvala at intel.com>

> ---
>  lib/igt_core.c    | 27 +++++++++++++++++++++------
>  runner/executor.c |  8 ++++----
>  2 files changed, 25 insertions(+), 10 deletions(-)
> 
> diff --git a/lib/igt_core.c b/lib/igt_core.c
> index e0989f538..64883d640 100644
> --- a/lib/igt_core.c
> +++ b/lib/igt_core.c
> @@ -1852,14 +1852,29 @@ static struct {
>  
>  static igt_exit_handler_t exit_handler_fn[MAX_EXIT_HANDLERS];
>  static bool exit_handler_disabled;
> +static const struct {
> +	int number;
> +	const char *name;
> +	size_t name_len;
> +} handled_signals[] = {
>  #define SIGDEF(x) { x, #x, sizeof(#x) - 1 }
>  #define SILENT(x) { x, NULL, 0 }
> -static const struct { int number; const char *name; size_t name_len; } handled_signals[] =
> -	{ SILENT(SIGINT), SILENT(SIGHUP), SILENT(SIGTERM), SILENT(SIGQUIT),
> -	  SILENT(SIGPIPE), SIGDEF(SIGABRT), SIGDEF(SIGSEGV), SIGDEF(SIGBUS),
> -	  SIGDEF(SIGFPE) };
> +
> +	SILENT(SIGINT),
> +	SILENT(SIGHUP),
> +	SILENT(SIGPIPE),
> +	SILENT(SIGTERM),
> +
> +	SIGDEF(SIGQUIT), /* used by igt_runner for its external timeout */
> +
> +	SIGDEF(SIGABRT),
> +	SIGDEF(SIGSEGV),
> +	SIGDEF(SIGBUS),
> +	SIGDEF(SIGFPE)
> +
>  #undef SILENT
>  #undef SIGDEF
> +};
>  
>  static int install_sig_handler(int sig_num, sighandler_t handler)
>  {
> @@ -1940,15 +1955,15 @@ static void fatal_sig_handler(int sig)
>  			__write_stderr(handled_signals[i].name,
>  				       handled_signals[i].name_len);
>  			write_stderr(".\n");
> +
> +			print_backtrace_sig_safe();
>  		}
>  
>  		if (crash_signal(sig)) {
>  			/* Linux standard to return exit code as 128 + signal */
>  			if (!failed_one)
>  				igt_exitcode = 128 + sig;
> -
>  			failed_one = true;
> -			print_backtrace_sig_safe();
>  
>  			if (in_subtest)
>  				exit_subtest("CRASH");
> diff --git a/runner/executor.c b/runner/executor.c
> index 4a0a1219a..4b5e01fdb 100644
> --- a/runner/executor.c
> +++ b/runner/executor.c
> @@ -510,11 +510,11 @@ static int monitor_output(pid_t child,
>  			switch (killed) {
>  			case 0:
>  				if (settings->log_level >= LOG_LEVEL_NORMAL) {
> -					printf("Timeout. Killing the current test with SIGTERM.\n");
> +					printf("Timeout. Killing the current test with SIGQUIT.\n");
>  					fflush(stdout);
>  				}
>  
> -				killed = SIGTERM;
> +				killed = SIGQUIT;
>  				if (!kill_child(killed, child))
>  					return -1;
>  
> @@ -526,7 +526,7 @@ static int monitor_output(pid_t child,
>  				watchdogs_set_timeout(120);
>  				intervals_left = timeout_intervals = 1;
>  				break;
> -			case SIGTERM:
> +			case SIGQUIT:
>  				if (settings->log_level >= LOG_LEVEL_NORMAL) {
>  					printf("Timeout. Killing the current test with SIGKILL.\n");
>  					fflush(stdout);
> @@ -706,7 +706,7 @@ static int monitor_output(pid_t child,
>  
>  				aborting = true;
>  				timeout = 2;
> -				killed = SIGTERM;
> +				killed = SIGQUIT;
>  				if (!kill_child(killed, child))
>  					return -1;
>  
> -- 
> 2.20.0.rc1
>