Commit b7b7c046 authored by Jim Harris's avatar Jim Harris
Browse files

spdk_trace: allow specifying a filename on command line 



This allows for offline debugging with a tracepoint
file - you can copy the shared memory file out of
/dev/shm to a normal file, then pass that in to this
trace app.

Note: Linux puts shared memory files in /dev/shm which
makes it easy to copy to a regular file.  FreeBSD does
not expose shared memory objects in this way - so for
now this capability to debug tracepoint files offline
will be limited primarily to Linux.

Signed-off-by: default avatarJim Harris <james.r.harris@intel.com>
Change-Id: I046b71bdd65cab5a76500775838a5072bec8da39

Reviewed-on: https://review.gerrithub.io/424284


Chandler-Test-Pool: SPDK Automated Test System <sys_sgsw@intel.com>
Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: default avatarChangpeng Liu <changpeng.liu@intel.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
parent 11a6ed23

app/trace/trace.cpp

+29 −5
Original line number Diff line number Diff line
@@ -290,11 +290,15 @@ static void usage(void) 
	fprintf(stderr, "usage:\n");

	fprintf(stderr, "   %s <option> <lcore#>\n", exe_name);

	fprintf(stderr, "        option = '-q' to disable verbose mode\n");

	fprintf(stderr, "                 '-s' to specify spdk_trace shm name\n");

	fprintf(stderr, "                 '-c' to display single lcore history\n");

	fprintf(stderr, "                 '-s' to specify spdk_trace shm name for a\n");

	fprintf(stderr, "                      currently running process\n");

	fprintf(stderr, "                 '-i' to specify the shared memory ID\n");

	fprintf(stderr, "                 '-p' to specify the trace PID\n");

	fprintf(stderr, "                 (One of -i or -p must be specified)\n");

	fprintf(stderr, "                      (If -s is specified, then one of\n");

	fprintf(stderr, "                       -i or -p must be specified)\n");

	fprintf(stderr, "                 '-f' to specify a tracepoint file name\n");

	fprintf(stderr, "                      (-s and -f are mutually exclusive)\n");

}



int main(int argc, char **argv)
@@ -304,7 +308,8 @@ int main(int argc, char **argv) 
	int			fd, i;

	int			lcore = SPDK_TRACE_MAX_LCORE;

	uint64_t		tsc_offset;

	const char		*app_name = "spdk";

	const char		*app_name = NULL;

	const char		*file_name = NULL;

	int			op;

	char			shm_name[64];

	int			shm_id = -1, shm_pid = -1;
@@ -333,21 +338,40 @@ int main(int argc, char **argv) 
		case 's':

			app_name = optarg;

			break;

		case 'f':

			file_name = optarg;

			break;

		default:

			usage();

			exit(1);

		}

	}



	if (file_name != NULL && app_name != NULL) {

		fprintf(stderr, "-f and -s are mutually exclusive\n");

		usage();

		exit(1);

	}



	if (file_name == NULL && app_name == NULL) {

		fprintf(stderr, "One of -f and -s must be specified\n");

		usage();

		exit(1);

	}



	if (shm_id >= 0) {

		snprintf(shm_name, sizeof(shm_name), "/%s_trace.%d", app_name, shm_id);

	} else {

		snprintf(shm_name, sizeof(shm_name), "/%s_trace.pid%d", app_name, shm_pid);

	}



	if (file_name) {

		fd = open(file_name, O_RDONLY);

	} else {

		fd = shm_open(shm_name, O_RDONLY, 0600);

	}

	if (fd < 0) {

		fprintf(stderr, "Could not open shm %s.\n", shm_name);

		fprintf(stderr, "Could not open %s.\n", file_name ? file_name : shm_name);

		usage();

		exit(-1);

	}